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2019 SkS Weekly Climate Change & Global Warming News Roundup #27

A chronological listing of news articles posted on the Skeptical Science Facebook Page during the past week, i.e., Sun, Jun 30 through Sat, July 6, 2019

Editor's Pick

German environment minister proposes carbon tax

Svenja Schulze has said such a plan is important for sinking carbon emissions, yet other measures are needed. She claims the plan would not unduly burden the poor, but reward those who use less fuel.

Germany's Social Democrat (SPD) Environment Minister Svenja Schulze  

Germany's Social Democrat (SPD) Environment Minister Svenja Schulze presented three independent studies on possible carbon tax schemes in Berlin on Friday. Insisting such a tax would not unduly burden the poor, she said, "those who decide to live a more climate-friendly life could actually get money back."

The plans Schulze presented suggested an initial €35 ($39.50) tax on each metric ton of CO2, to be increased to €180 by 2030. The idea being that the more expensive petrol, natural gas, and heating oil become, the less people will use.

Schulze told reporters that those who consume less, including children, will be given a so-called climate bonus of up to €100 per person, per year, which she claims would offset a person's outlay for the tax, "The less you drive, the less oil you burn, the more you will get back."

The minister underscored the importance of not burdening low and middle-class families: "It's really important to me to avoid unfairly burdening those with low and medium incomes, and especially affected groups like commuters and tenants." 

German environment minister proposes carbon tax, Deutsche Welle (DW), July 5, 2019 

Links posted on Facebook

Sun June 30, 2019

Mon July 1, 2019

Tue July 2, 2019

Wed July 3, 2019

Thur July 4, 2019

Fri July 5, 2019

Sat July 6, 2019



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A chronological listing of news articles posted on the Skeptical Science Facebook Page during the past week, i.e., Sun, Jun 30 through Sat, July 6, 2019

Editor's Pick

German environment minister proposes carbon tax

Svenja Schulze has said such a plan is important for sinking carbon emissions, yet other measures are needed. She claims the plan would not unduly burden the poor, but reward those who use less fuel.

Germany's Social Democrat (SPD) Environment Minister Svenja Schulze  

Germany's Social Democrat (SPD) Environment Minister Svenja Schulze presented three independent studies on possible carbon tax schemes in Berlin on Friday. Insisting such a tax would not unduly burden the poor, she said, "those who decide to live a more climate-friendly life could actually get money back."

The plans Schulze presented suggested an initial €35 ($39.50) tax on each metric ton of CO2, to be increased to €180 by 2030. The idea being that the more expensive petrol, natural gas, and heating oil become, the less people will use.

Schulze told reporters that those who consume less, including children, will be given a so-called climate bonus of up to €100 per person, per year, which she claims would offset a person's outlay for the tax, "The less you drive, the less oil you burn, the more you will get back."

The minister underscored the importance of not burdening low and middle-class families: "It's really important to me to avoid unfairly burdening those with low and medium incomes, and especially affected groups like commuters and tenants." 

German environment minister proposes carbon tax, Deutsche Welle (DW), July 5, 2019 

Links posted on Facebook

Sun June 30, 2019

Mon July 1, 2019

Tue July 2, 2019

Wed July 3, 2019

Thur July 4, 2019

Fri July 5, 2019

Sat July 6, 2019



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California shakes from 2nd big quake in 2 days

Map showing desert location of July 6 California earthquake.

The magnitude 7.1 earthquake on July 6, 2019, took place 10.5 miles (17 km) north-northeast of Ridgecrest, California, in the Mojave desert. Read more about nearby places from USGS.

The second large earthquake in two days shook the Ridgecrest area of eastern California – in the Mojave desert – last night. It took place approximately 34 hours after and 7 miles (11 km) northwest of a 6.4-magnitude foreshock, which happened on July 4 in a nearby remote area of California’s San Bernardino County. The 7.1-magnitude earthquake took place at 03:19 UTC on July 6, 2019 (8:19 p.m. Pacific Daylight Time on July 5; translate UTC to your time). The epicenter of the quake was 10.5 miles (17 km) north-northeast of Ridgecrest, California, southwest of Searles Valley and not far from Death Valley National Park. Scientists are referring to this earthquake series (which also consists of numerous minor quakes) as the Searles sequence. The sequence includes two other magnitude 5+ earthquakes, one of which occurred 20 seconds before the 7.1-magnitude event.

Relatively minor damage resulted from the initial foreshock, though some building fires were reported in Ridgecrest, California, near the epicenter. Effects were felt across much of Southern California, parts of Arizona and Nevada, as far north as the San Francisco Bay Area, and as far south as Baja California, Mexico. An estimated 20 million people experienced the foreshock and 30 million people experienced the earthquake.

Ridgecrest is a small city in Kern County, California, with a population of 27,616 at the 2010 census. Thus the 7.1-magnitude quake took place in a low-population region. Ridgecrest is approximately 82 miles (132 km) from the Lancaster/Palmdale area, 110 miles (177 km) from Bakersfield, and 120 miles (193 km) from San Bernardino, the three nearest major urban centers.

Ridgecrest has been near the epicenter of major earthquakes, including one in 1995 and now this July 2019 series of quakes. This 6.4-magnitude quake was preceded by a short series of small foreshocks (including a M4.0 earthquake 30 minutes prior), and was followed by a robust sequence of aftershocks, including almost 250 2.5+ magnitude earthquakes (up until the 7.1-magnitude event). The day after, the 7.1-magnitude mainshock occurred near the same location.

California earthquake scientist Lucy Jones of the U.S. Geological Survey (USGS) – who frequently serves as a public voice for science on the subject of California earthquakes – said that the 7.1-magnitude quake is not expected to trigger more quakes or larger quakes outside the Ridgecrest, California, area.

USGS said:

The July 6th, 2019, 03:19 UTC (July 5th 20:19 locally) Mw 7.1 earthquake in eastern California, southwest of Searles Valley, occurred as the result of shallow strike slip faulting in the crust of the North American plate … At the location of this earthquake, approximately 150 km [93 mi] northeast of San Andreas Fault – the major plate boundary in the region – the Pacific plate moves to the northwest with respect to the North America plate at a rate of approximately 48 mm/yr [almost 2 inches/yr]. The location of the earthquake falls within the Eastern California shear zone, a region of distributed faulting associated with motion across the Pacific-North America plate boundary, and an area of high seismic hazard.

More detailed studies will be required to precisely identify the causative fault associated with this event, though seismic activity over the past 2 days has been occurring on two conjugate fault structures in the Airport Lake Fault Zone …

This region of eastern California has hosted numerous moderate sized earthquakes. Over the past 40 years, prior to the July 4th event, 8 other M5+ earthquakes have occurred within 50 km [30 mi] of the July 6th, 2019, earthquake. The largest of these was a M 5.8 event on September 20, 1995, just 3 km [1.9 mi] to the west of today’s event, which was felt strongly in the China Lake-Ridgecrest area, and more broadly from Los Angeles to Las Vegas.

Bottom line: A 7.1-magnitude earthquake took place on July 5, 2019, at 8:19 p.m. Pacific Daylight Time (July 6 at 03:19 UTC). It took place near Ridgecrest, California (population 27,616 at the 2010 census), in the Mojave Desert. Earthquake scientist Lucy Jones said, “… the M6.4 was a foreshock. This was a M7.1 on the same fault.” Building fires reported in Ridgecrest. Effects felt across much of Southern California, parts of Arizona and Nevada, as far north as the San Francisco Bay Area, and as far south as Baja California, Mexico.



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Map showing desert location of July 6 California earthquake.

The magnitude 7.1 earthquake on July 6, 2019, took place 10.5 miles (17 km) north-northeast of Ridgecrest, California, in the Mojave desert. Read more about nearby places from USGS.

The second large earthquake in two days shook the Ridgecrest area of eastern California – in the Mojave desert – last night. It took place approximately 34 hours after and 7 miles (11 km) northwest of a 6.4-magnitude foreshock, which happened on July 4 in a nearby remote area of California’s San Bernardino County. The 7.1-magnitude earthquake took place at 03:19 UTC on July 6, 2019 (8:19 p.m. Pacific Daylight Time on July 5; translate UTC to your time). The epicenter of the quake was 10.5 miles (17 km) north-northeast of Ridgecrest, California, southwest of Searles Valley and not far from Death Valley National Park. Scientists are referring to this earthquake series (which also consists of numerous minor quakes) as the Searles sequence. The sequence includes two other magnitude 5+ earthquakes, one of which occurred 20 seconds before the 7.1-magnitude event.

Relatively minor damage resulted from the initial foreshock, though some building fires were reported in Ridgecrest, California, near the epicenter. Effects were felt across much of Southern California, parts of Arizona and Nevada, as far north as the San Francisco Bay Area, and as far south as Baja California, Mexico. An estimated 20 million people experienced the foreshock and 30 million people experienced the earthquake.

Ridgecrest is a small city in Kern County, California, with a population of 27,616 at the 2010 census. Thus the 7.1-magnitude quake took place in a low-population region. Ridgecrest is approximately 82 miles (132 km) from the Lancaster/Palmdale area, 110 miles (177 km) from Bakersfield, and 120 miles (193 km) from San Bernardino, the three nearest major urban centers.

Ridgecrest has been near the epicenter of major earthquakes, including one in 1995 and now this July 2019 series of quakes. This 6.4-magnitude quake was preceded by a short series of small foreshocks (including a M4.0 earthquake 30 minutes prior), and was followed by a robust sequence of aftershocks, including almost 250 2.5+ magnitude earthquakes (up until the 7.1-magnitude event). The day after, the 7.1-magnitude mainshock occurred near the same location.

California earthquake scientist Lucy Jones of the U.S. Geological Survey (USGS) – who frequently serves as a public voice for science on the subject of California earthquakes – said that the 7.1-magnitude quake is not expected to trigger more quakes or larger quakes outside the Ridgecrest, California, area.

USGS said:

The July 6th, 2019, 03:19 UTC (July 5th 20:19 locally) Mw 7.1 earthquake in eastern California, southwest of Searles Valley, occurred as the result of shallow strike slip faulting in the crust of the North American plate … At the location of this earthquake, approximately 150 km [93 mi] northeast of San Andreas Fault – the major plate boundary in the region – the Pacific plate moves to the northwest with respect to the North America plate at a rate of approximately 48 mm/yr [almost 2 inches/yr]. The location of the earthquake falls within the Eastern California shear zone, a region of distributed faulting associated with motion across the Pacific-North America plate boundary, and an area of high seismic hazard.

More detailed studies will be required to precisely identify the causative fault associated with this event, though seismic activity over the past 2 days has been occurring on two conjugate fault structures in the Airport Lake Fault Zone …

This region of eastern California has hosted numerous moderate sized earthquakes. Over the past 40 years, prior to the July 4th event, 8 other M5+ earthquakes have occurred within 50 km [30 mi] of the July 6th, 2019, earthquake. The largest of these was a M 5.8 event on September 20, 1995, just 3 km [1.9 mi] to the west of today’s event, which was felt strongly in the China Lake-Ridgecrest area, and more broadly from Los Angeles to Las Vegas.

Bottom line: A 7.1-magnitude earthquake took place on July 5, 2019, at 8:19 p.m. Pacific Daylight Time (July 6 at 03:19 UTC). It took place near Ridgecrest, California (population 27,616 at the 2010 census), in the Mojave Desert. Earthquake scientist Lucy Jones said, “… the M6.4 was a foreshock. This was a M7.1 on the same fault.” Building fires reported in Ridgecrest. Effects felt across much of Southern California, parts of Arizona and Nevada, as far north as the San Francisco Bay Area, and as far south as Baja California, Mexico.



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Coathanger: Looks like its name

Image via Wikipedia.

The Coathanger or Brocchi’s cluster is a tiny asterism – pattern of stars that is not a constellation. This star formation looks exactly like its namesake, and is amazingly easy to make out through binoculars. The whole trick to viewing the Coathanger is to know just where to look.

As a prerequisite, first find the star Albireo in the Northern Cross asterism. The Northern Cross is actually a clipped version of the constellation Cygnus the Swan, with Albireo depicting the Swan’s eye or beak. The entire Northern Cross asterism is within another famous asterism, the Summer Triangle.

Albireo, Alpha Vulpeculae, and the Coathanger

Albireo, Alpha Vulpeculae, and the Coathanger

Albireo is found at the base of the Northern Cross.

Got Albireo? Now for some specifics on finding the Coathanger. With binoculars, look for the brightest star in the vicinity of Albireo. That star is called Alpha Vulpeculae, which appears as a double star through binoculars (though the two stars are not gravitationally bound).

Image via Astrobob

The Northern Cross, with Albireo at its base and the Coathanger nearby, via Astrobob

Draw an imaginary line from Albireo through Alpha Vulpeculae to locate the Coathanger. In most binoculars, Alpha Vulpeculae and the Coathanger fit within the same binocular field of view, though just barely.

View larger. | An imaginary line – drawn in purple on this chart – from the star Albireo and through the star Alpha Vulpeculae takes you to the Coathanger.

Notice that six stars form the bar of the Coathanger, while four stars make up the hook. From mid-northern latitudes, the Coathanger often appears upside-down. That’s why some people call it the Ski Lift.

Hint: The Coathanger is tiny. If you keep getting lost while using your binoculars, place it at the top of a tree (or building), then your landmark upward with binoculars until you catch sight of the object.

When should you look? Our sky chart above shows the stars as they appear from the Northern Hemisphere in middle July around midnight (1 a.m. Daylight Saving Time).

Because the stars return to the same place in the sky some 2 hours earlier with each passing month, this sky chart also shows star positions for about 10 p.m. (11 p.m. Daylight Time) in mid-August, 8 p.m. (9 p.m. Daylight Time) in mid-September and 6 p.m (7 p.m Daylight Time) in mid-October.

Since these stars shine from south to overhead at these times (as seen from the Northern Hemisphere), you might want to sprawl out on a reclining lawn chair, with your feet pointing southward. A reclining position saves on neck strain.

Incidentally, the Coathanger – aka Brocchi’s cluster – isn’t a true cluster, but a chance alignment of physically unrelated stars.

The Coathanger’s position is at RA: 19h 26.47′; Dec: 20o 11.93′

Photo of the Coathanger cluster, courtesy of Jean Marie Andre Delaporte. Thank you Jean Marie! The Coathanger is to the lower right. See more great photos on the EarthSky Facebook page.

Photo of the Coathanger cluster (on the lower right). Image via Jean Marie Andre Delaporte. Thank you, Jean Marie!

Bottom line: Star-hop to the Coathanger – a tiny asterism that really looks like its namesake – via the stars Albireo and Alpha Vulpeculae.

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Image via Wikipedia.

The Coathanger or Brocchi’s cluster is a tiny asterism – pattern of stars that is not a constellation. This star formation looks exactly like its namesake, and is amazingly easy to make out through binoculars. The whole trick to viewing the Coathanger is to know just where to look.

As a prerequisite, first find the star Albireo in the Northern Cross asterism. The Northern Cross is actually a clipped version of the constellation Cygnus the Swan, with Albireo depicting the Swan’s eye or beak. The entire Northern Cross asterism is within another famous asterism, the Summer Triangle.

Albireo, Alpha Vulpeculae, and the Coathanger

Albireo, Alpha Vulpeculae, and the Coathanger

Albireo is found at the base of the Northern Cross.

Got Albireo? Now for some specifics on finding the Coathanger. With binoculars, look for the brightest star in the vicinity of Albireo. That star is called Alpha Vulpeculae, which appears as a double star through binoculars (though the two stars are not gravitationally bound).

Image via Astrobob

The Northern Cross, with Albireo at its base and the Coathanger nearby, via Astrobob

Draw an imaginary line from Albireo through Alpha Vulpeculae to locate the Coathanger. In most binoculars, Alpha Vulpeculae and the Coathanger fit within the same binocular field of view, though just barely.

View larger. | An imaginary line – drawn in purple on this chart – from the star Albireo and through the star Alpha Vulpeculae takes you to the Coathanger.

Notice that six stars form the bar of the Coathanger, while four stars make up the hook. From mid-northern latitudes, the Coathanger often appears upside-down. That’s why some people call it the Ski Lift.

Hint: The Coathanger is tiny. If you keep getting lost while using your binoculars, place it at the top of a tree (or building), then your landmark upward with binoculars until you catch sight of the object.

When should you look? Our sky chart above shows the stars as they appear from the Northern Hemisphere in middle July around midnight (1 a.m. Daylight Saving Time).

Because the stars return to the same place in the sky some 2 hours earlier with each passing month, this sky chart also shows star positions for about 10 p.m. (11 p.m. Daylight Time) in mid-August, 8 p.m. (9 p.m. Daylight Time) in mid-September and 6 p.m (7 p.m Daylight Time) in mid-October.

Since these stars shine from south to overhead at these times (as seen from the Northern Hemisphere), you might want to sprawl out on a reclining lawn chair, with your feet pointing southward. A reclining position saves on neck strain.

Incidentally, the Coathanger – aka Brocchi’s cluster – isn’t a true cluster, but a chance alignment of physically unrelated stars.

The Coathanger’s position is at RA: 19h 26.47′; Dec: 20o 11.93′

Photo of the Coathanger cluster, courtesy of Jean Marie Andre Delaporte. Thank you Jean Marie! The Coathanger is to the lower right. See more great photos on the EarthSky Facebook page.

Photo of the Coathanger cluster (on the lower right). Image via Jean Marie Andre Delaporte. Thank you, Jean Marie!

Bottom line: Star-hop to the Coathanger – a tiny asterism that really looks like its namesake – via the stars Albireo and Alpha Vulpeculae.

Enjoying EarthSky so far? Sign up for our free daily newsletter today!



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See Corona Borealis, the Northern Crown

Tonight, look for the constellation Corona Borealis, also known as the Northern Crown. You’ll need a pretty dark sky to see it, but, if you have one, the constellation is easy to pick out because it makes the shape of the letter C. Hopefully, tonight’s waxing crescent moon won’t be too intrusive, but remember that the last week of July 2019 will offer deliciously dark skies.

To see this famous C-shaped assemblage of stars from the Northern Hemisphere, during the evening hours in July, you’ll be looking high overhead. From the Southern Hemisphere, the constellation is low in the northern sky. The Corona Borealis constellation is distinctive. It looks like a half-circle, in the middle of which is a white jewel of a star called Alphecca or Gemma.

EarthSky astronomy kits are perfect for beginners. Order yours today.

Star chart with many background stars with variable stars labeled.

R and T Corona Borealis are famous variable stars in this constellation. Image via skyandtelescope.com.

The Crown is located more or less along a line between two bright stars: Arcturus in the constellation Boötes the Herdsman and Vega in the constellation Lyra the Harp.

Arcturus has already passed its highest point in the evening at this time of year and is slowly descending to the west. Vega is still high in the east on July evenings. With dark skies you will notice the orange color of Arcturus, and Vega’s bright blue-white tinge.

Corona Borealis can be found between these two stars, though closer to Vega. Remember, a dark sky is best for seeing the faint semicircle of stars composing this constellation.

Star chart with Arcturus and Vega labeled and small constellation between them.

Look for Corona Borealis between the stars Vega and Arcturus.

By the way, the meaning of the Latin star name Gemma should be obvious. This star is the gem of the Northern Crown.

But the star is also called Alphecca, from an Arabic phrase meaning the bright one of the dish.

Gemma, aka Alphecca, is an eclipsing binary system. It consists of a smaller sunlike star that passes in front of a brighter star every 17.4 days, as seen from our earthly vantage point.

Large glowing orange sun with part of smaller yellow sun visible behind it.

Artist’s concept of an eclipsing binary star system, via Jay Devvy.

Bottom line: On these July evenings, look for Corona Borealis’ graceful semicircle of stars between two bright stars: Arcturus and Vega.



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Tonight, look for the constellation Corona Borealis, also known as the Northern Crown. You’ll need a pretty dark sky to see it, but, if you have one, the constellation is easy to pick out because it makes the shape of the letter C. Hopefully, tonight’s waxing crescent moon won’t be too intrusive, but remember that the last week of July 2019 will offer deliciously dark skies.

To see this famous C-shaped assemblage of stars from the Northern Hemisphere, during the evening hours in July, you’ll be looking high overhead. From the Southern Hemisphere, the constellation is low in the northern sky. The Corona Borealis constellation is distinctive. It looks like a half-circle, in the middle of which is a white jewel of a star called Alphecca or Gemma.

EarthSky astronomy kits are perfect for beginners. Order yours today.

Star chart with many background stars with variable stars labeled.

R and T Corona Borealis are famous variable stars in this constellation. Image via skyandtelescope.com.

The Crown is located more or less along a line between two bright stars: Arcturus in the constellation Boötes the Herdsman and Vega in the constellation Lyra the Harp.

Arcturus has already passed its highest point in the evening at this time of year and is slowly descending to the west. Vega is still high in the east on July evenings. With dark skies you will notice the orange color of Arcturus, and Vega’s bright blue-white tinge.

Corona Borealis can be found between these two stars, though closer to Vega. Remember, a dark sky is best for seeing the faint semicircle of stars composing this constellation.

Star chart with Arcturus and Vega labeled and small constellation between them.

Look for Corona Borealis between the stars Vega and Arcturus.

By the way, the meaning of the Latin star name Gemma should be obvious. This star is the gem of the Northern Crown.

But the star is also called Alphecca, from an Arabic phrase meaning the bright one of the dish.

Gemma, aka Alphecca, is an eclipsing binary system. It consists of a smaller sunlike star that passes in front of a brighter star every 17.4 days, as seen from our earthly vantage point.

Large glowing orange sun with part of smaller yellow sun visible behind it.

Artist’s concept of an eclipsing binary star system, via Jay Devvy.

Bottom line: On these July evenings, look for Corona Borealis’ graceful semicircle of stars between two bright stars: Arcturus and Vega.



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News digest – obesity, drug decisions, NHS waiting times and a cancer killing virus

Obesity responsible for more cases of some cancers than smoking

We released new figures showing that being overweight or obese tops smoking as the leading cause of 4 types of cancer, and it dominated headlines this week. The story was timed with our latest obesity campaign, which calls for the Government to act now to help protect children from junk food marketing and restrict promotional offers on unhealthy food and drinks.

The campaign sparked debate on social media and among some academics and nutritionists. Our CEO, Michelle Mitchell, responded: “Our focus is on raising awareness of the facts and paving the way for effective public health policy.”

Boris Johnson promises ‘sugar tax review’

In related news, Conservative leadership hopeful Boris Johnson sparked headlines when he vowed to examine if taxes on foods high in sugar, salt and fat are working. The ‘sugar tax’ was introduced in April 2018, but Johnson says he’s concerned the taxes unfairly target the less well off, according to BBC News. The move comes days before health secretary, Matt Hancock, is expected to recommend extending the sugar tax to milkshakes and a week before Conservative party members begin voting for their preferred leader, as The Guardian explains.

Skin cancer immunotherapy added to Cancer Drugs Fund

Some people with advanced skin cancer will now have access to a new immunotherapy on the NHS. This approval was particularly notable because it was made immediately after the drug got European approval, which means patients in England will be among the first in Europe to receive the treatment. Wales and Northern Ireland are likely to follow this decision, as our news report explains.

Double NICE decision for lung cancer drugs in England

The National Institute of Health and Care Excellence (NICE) has been busy this week, releasing two further cancer drug decisions – this time for targeted lung cancer treatments. Both drugs were being looked at for some adults with untreated, advanced lung cancer, but only one was approved for NHS use. The decisions are also likely to affect patients in Northern Ireland and Wales. Our news report and the Mail Online have the details.

Waiting times for cancer diagnosis in England revealed

And they paint a concerning picture. Data for lung and bowel cancers reveal huge variation in how long people wait for their diagnosis. Those who were urgently referred by their GP were diagnosed within 36 days on average in 2015, but this rose to 69 days for a routine GP referral. And 1 in 4 people waited at least 126 days for their diagnosis. The new figures from Cancer Research UK and Public Health England were covered by the Telegraph and our blog post, which highlights NHS staff shortages as one of the biggest barriers to diagnosing cancers earlier.

UK’s ‘biggest lung cancer study’ starts in London

25,000 adults with a history of smoking will be invited to take part in a study aiming to detect lung cancer earlier, reports the Evening Standard. The project, which made headlines back in December 2018, will invite people to have a phone interview followed by a breath test and CT scan if necessary, as well as blood tests. The project will also recruit 25,000 non-smokers aged between 50 and 77. The project is similar but separate to NHS ‘targeted lung health check’ pilots being rolled out across England, which we covered back in February.

More gene faults linked to prostate cancer risk

Scientists in London have homed in on more faulty genes that can slightly increase the risk of prostate cancer, according to this opinion piece in the Mirror. And four of these faults have been linked to developing more aggressive tumours. While talk of a quick DNA test is a bit premature, understanding more about how DNA faults are linked with prostate cancer risk, and what to do with the information, is a vital area of research. Check out our blog post for more on the future of prostate cancer diagnosis.

Brexit uncertainty ‘making research partners nervous’, says leading cancer scientist

The Guardian looked at how the threat of a no-deal Brexit could be affecting UK science, after analysis by University College London shows the number of European research collaborations led by top UK universities had dropped significantly since the referendum vote in 2016. Professor Pam Kearns, a Cancer Research UK-funded childhood cancer expert in Birmingham, said it would be “unacceptable” for the UK not to be a partner in a united approach to cancer research.

Lesbian, gay and bisexual women missing out on cervical screening, says NHS survey

Thousands could be missing out on screening because of a “dangerous myth” that lesbian, gay and bisexual (LGB) women are not at risk of cervical cancer, says NHS England. New survey results suggest nearly 1 in 5 LGB women have never attended cervical screening, despite the fact the human papillomavirus (HPV), which causes most cervical cancers, can be passed on by close skin-to-skin contact regardless of gender or sexual orientation. Professor Anne Mackie, Public Health England’s director of screening encouraged “anyone with a cervix, between the ages of 25 and 64, to go for regular cervical screening.” Mail Online has this one.

People with cancer should be prescribed fitness plans, say charities

A group of charities have recommended that all newly diagnosed cancer patients be given personalised lifestyle guidance to help boost their resilience to treatment. The report by Macmillan Cancer Support and others comes off the back of a series of studies showing exercise can help reduce the chance of an early death, according to the Telegraph.

Scientists identify new protein involved in regulating cancer cell stress

Cancer cells find ways to deal with various stresses to survive, including the rapid production of proteins linked to a faulty gene called MYC. Scientists have tried for years to target this particular fault, with little success. Now researchers have identified a new player in the vital stress response, which could prove to be a new target for cancer drugs. It’s an exciting new piece of the puzzle, but the results are so far only in mice with lymphoma, meaning talk of it being the ‘Achilles heel’ of cancer is premature.

Cancer Research UK joins biotech investment fund

We’ve joined up with venture capital firm SV Health to create a £200 million investment fund focused on innovative cancer treatments. It’s the first time we’ve partnered with a venture capital firm and the plan is for at least 60% of the money to be invested in cancer research. The Financial Times (£) and Pharma Times covered the announcement.

And finally

Scientists have used a modified version of the common cold virus to infect and kill bladder cancer cells, reports BBC News. It’s still early days: the treatment has so far been tested in 15 patients with non-muscle invasive bladder cancer. But scientists found evidence that the treatment had targeted and killed cancer cells in tissue samples taken during surgery. The next step is to really put the treatment to the test in larger trials.

Katie



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Obesity responsible for more cases of some cancers than smoking

We released new figures showing that being overweight or obese tops smoking as the leading cause of 4 types of cancer, and it dominated headlines this week. The story was timed with our latest obesity campaign, which calls for the Government to act now to help protect children from junk food marketing and restrict promotional offers on unhealthy food and drinks.

The campaign sparked debate on social media and among some academics and nutritionists. Our CEO, Michelle Mitchell, responded: “Our focus is on raising awareness of the facts and paving the way for effective public health policy.”

Boris Johnson promises ‘sugar tax review’

In related news, Conservative leadership hopeful Boris Johnson sparked headlines when he vowed to examine if taxes on foods high in sugar, salt and fat are working. The ‘sugar tax’ was introduced in April 2018, but Johnson says he’s concerned the taxes unfairly target the less well off, according to BBC News. The move comes days before health secretary, Matt Hancock, is expected to recommend extending the sugar tax to milkshakes and a week before Conservative party members begin voting for their preferred leader, as The Guardian explains.

Skin cancer immunotherapy added to Cancer Drugs Fund

Some people with advanced skin cancer will now have access to a new immunotherapy on the NHS. This approval was particularly notable because it was made immediately after the drug got European approval, which means patients in England will be among the first in Europe to receive the treatment. Wales and Northern Ireland are likely to follow this decision, as our news report explains.

Double NICE decision for lung cancer drugs in England

The National Institute of Health and Care Excellence (NICE) has been busy this week, releasing two further cancer drug decisions – this time for targeted lung cancer treatments. Both drugs were being looked at for some adults with untreated, advanced lung cancer, but only one was approved for NHS use. The decisions are also likely to affect patients in Northern Ireland and Wales. Our news report and the Mail Online have the details.

Waiting times for cancer diagnosis in England revealed

And they paint a concerning picture. Data for lung and bowel cancers reveal huge variation in how long people wait for their diagnosis. Those who were urgently referred by their GP were diagnosed within 36 days on average in 2015, but this rose to 69 days for a routine GP referral. And 1 in 4 people waited at least 126 days for their diagnosis. The new figures from Cancer Research UK and Public Health England were covered by the Telegraph and our blog post, which highlights NHS staff shortages as one of the biggest barriers to diagnosing cancers earlier.

UK’s ‘biggest lung cancer study’ starts in London

25,000 adults with a history of smoking will be invited to take part in a study aiming to detect lung cancer earlier, reports the Evening Standard. The project, which made headlines back in December 2018, will invite people to have a phone interview followed by a breath test and CT scan if necessary, as well as blood tests. The project will also recruit 25,000 non-smokers aged between 50 and 77. The project is similar but separate to NHS ‘targeted lung health check’ pilots being rolled out across England, which we covered back in February.

More gene faults linked to prostate cancer risk

Scientists in London have homed in on more faulty genes that can slightly increase the risk of prostate cancer, according to this opinion piece in the Mirror. And four of these faults have been linked to developing more aggressive tumours. While talk of a quick DNA test is a bit premature, understanding more about how DNA faults are linked with prostate cancer risk, and what to do with the information, is a vital area of research. Check out our blog post for more on the future of prostate cancer diagnosis.

Brexit uncertainty ‘making research partners nervous’, says leading cancer scientist

The Guardian looked at how the threat of a no-deal Brexit could be affecting UK science, after analysis by University College London shows the number of European research collaborations led by top UK universities had dropped significantly since the referendum vote in 2016. Professor Pam Kearns, a Cancer Research UK-funded childhood cancer expert in Birmingham, said it would be “unacceptable” for the UK not to be a partner in a united approach to cancer research.

Lesbian, gay and bisexual women missing out on cervical screening, says NHS survey

Thousands could be missing out on screening because of a “dangerous myth” that lesbian, gay and bisexual (LGB) women are not at risk of cervical cancer, says NHS England. New survey results suggest nearly 1 in 5 LGB women have never attended cervical screening, despite the fact the human papillomavirus (HPV), which causes most cervical cancers, can be passed on by close skin-to-skin contact regardless of gender or sexual orientation. Professor Anne Mackie, Public Health England’s director of screening encouraged “anyone with a cervix, between the ages of 25 and 64, to go for regular cervical screening.” Mail Online has this one.

People with cancer should be prescribed fitness plans, say charities

A group of charities have recommended that all newly diagnosed cancer patients be given personalised lifestyle guidance to help boost their resilience to treatment. The report by Macmillan Cancer Support and others comes off the back of a series of studies showing exercise can help reduce the chance of an early death, according to the Telegraph.

Scientists identify new protein involved in regulating cancer cell stress

Cancer cells find ways to deal with various stresses to survive, including the rapid production of proteins linked to a faulty gene called MYC. Scientists have tried for years to target this particular fault, with little success. Now researchers have identified a new player in the vital stress response, which could prove to be a new target for cancer drugs. It’s an exciting new piece of the puzzle, but the results are so far only in mice with lymphoma, meaning talk of it being the ‘Achilles heel’ of cancer is premature.

Cancer Research UK joins biotech investment fund

We’ve joined up with venture capital firm SV Health to create a £200 million investment fund focused on innovative cancer treatments. It’s the first time we’ve partnered with a venture capital firm and the plan is for at least 60% of the money to be invested in cancer research. The Financial Times (£) and Pharma Times covered the announcement.

And finally

Scientists have used a modified version of the common cold virus to infect and kill bladder cancer cells, reports BBC News. It’s still early days: the treatment has so far been tested in 15 patients with non-muscle invasive bladder cancer. But scientists found evidence that the treatment had targeted and killed cancer cells in tissue samples taken during surgery. The next step is to really put the treatment to the test in larger trials.

Katie



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Where to find big ideas for addressing climate change

This is a re-post from Yale Climate Connections by SueEllen Campbell

Sometimes we all need a boost of optimism about our prospects of staving off the worst kinds of climate disruption. We also need to see big thinking and big ambition in practice – or, we might say, to see how ideas can be scaled up, even way up.

Here are some excellent places to look for this kind of inspiration.

  • Project Drawdown. As the project guru Paul Hawken says in a NYT interview, “a primary goal” of this research, book, and website “is to help people who feel overwhelmed by gloom-and-doom messages see that reversing global warming is bursting with possibility.” What are the 100 most effective ways to bring down atmospheric carbon dioxide? The surprising data-driven answers here can help us direct our collective energies where they will count most.
  • Rocky Mountain Institute. With its mission to transform “global energy use,” the Rocky Mountain Institute deploys all kind of smart ideas about new technologies and radical efficiency. Watch the TED Talk by director Amory Lovins, and then look at the website page about the book behind that talk, Reinventing Fire. This is a kind of futuristic optimism even a cynic may find encouraging.
  • This short piece by Ben Brown (communication specialist for PlaceMakers, an urban planning firm) offers an overview of some places where climate action is happening now, especially in towns, cities, and regions. Drawing on the work of Jim Fox, director of the National Environmental Modeling and Analysis Center, and on Brown’s idea of “Leveraging ‘The Biggest Little Things,'” this blog entry reminds us that “The best strategies are the ones that can be implemented.”
  • Finally, if your bent is less technological than personal and humanistic, take a look at a pre-Drawdown essay by Paul Hawken in Orion Magazine, “To Remake the World.” This heartening piece is also about scaling up – but on a quite different front, that of the astonishing number of small grassroots organizations around the globe.

This series is curated and written by retired Colorado State University English professor and close climate change watcher SueEllen Campbell of Colorado. To flag works you think warrant attention, send an e-mail to her any time. Let us hear from you.



from Skeptical Science https://ift.tt/2LMmVyz

This is a re-post from Yale Climate Connections by SueEllen Campbell

Sometimes we all need a boost of optimism about our prospects of staving off the worst kinds of climate disruption. We also need to see big thinking and big ambition in practice – or, we might say, to see how ideas can be scaled up, even way up.

Here are some excellent places to look for this kind of inspiration.

  • Project Drawdown. As the project guru Paul Hawken says in a NYT interview, “a primary goal” of this research, book, and website “is to help people who feel overwhelmed by gloom-and-doom messages see that reversing global warming is bursting with possibility.” What are the 100 most effective ways to bring down atmospheric carbon dioxide? The surprising data-driven answers here can help us direct our collective energies where they will count most.
  • Rocky Mountain Institute. With its mission to transform “global energy use,” the Rocky Mountain Institute deploys all kind of smart ideas about new technologies and radical efficiency. Watch the TED Talk by director Amory Lovins, and then look at the website page about the book behind that talk, Reinventing Fire. This is a kind of futuristic optimism even a cynic may find encouraging.
  • This short piece by Ben Brown (communication specialist for PlaceMakers, an urban planning firm) offers an overview of some places where climate action is happening now, especially in towns, cities, and regions. Drawing on the work of Jim Fox, director of the National Environmental Modeling and Analysis Center, and on Brown’s idea of “Leveraging ‘The Biggest Little Things,'” this blog entry reminds us that “The best strategies are the ones that can be implemented.”
  • Finally, if your bent is less technological than personal and humanistic, take a look at a pre-Drawdown essay by Paul Hawken in Orion Magazine, “To Remake the World.” This heartening piece is also about scaling up – but on a quite different front, that of the astonishing number of small grassroots organizations around the globe.

This series is curated and written by retired Colorado State University English professor and close climate change watcher SueEllen Campbell of Colorado. To flag works you think warrant attention, send an e-mail to her any time. Let us hear from you.



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The HadSST4 Sea Surface Temperature dataset

The oceans cover two thirds of the surface of the earth, and so sea surface temperatures form a vital part of our understanding of the impact of human activity on the temperature of the planet. Sea surface temperatures contribute to estimates of global surface temperature change which are widely used in the evaluation of climate models, the estimation of internal modes of climate variability, and the setting of political targets. The ways in which sea surface temperatures have been measured by ships, buoys and satellites have varied much more significantly over time than equipment at weather stations; these changes have to be corrected when evaluating historical temperature change. Differences between different sea surface temperature datasets highlight where some of these corrections are uncertain, however users of temperature data frequently ignore these uncertainties and the effect they may have on their conclusions.

This issue was highlighted in a paper by Kent and colleagues in 2017, which made a call for action both for temperature record providers to make more progress on these issues, and for users to be aware of what the data can and cannot tell us. A number of authors have responded by investigating aspects of the sea surface temperature record (e.g. Hausfather et al 2017, Cowtan et al, 2017, Carella et al 2018, Davis et al 2018). Last week the latest version of the UK Hadley centre sea surface temperature dataset, HadSST4, was released.

The Hadley centre have been at the forefront of the development of sea surface temperature data for many years, providing the only sea record which attempts to reconcile the measurement types of individual observations. A Japanese dataset, COBE-SST2, also uses the Hadley analysis of data corrections in combination with an alternative post-processing algorithm to produce an infilled sea surface temperature reconstruction.

Other datasets apply more coarse grained corrections: NOAA's ERSST (Huang et al, 2017) corrects the gridded ship temperature field on the basis of smoothed differences between water and air temperature measurements, while my own coastal hybrid reconstruction (Cowtan et al, 2017) uses coastal weather stations to estimate a global correction for the combined impact of different types of sea surface temperature observations.

The problem is that these methods lead to different answers (Figure 1), suggesting that the required corrections for the different observations are not yet well understood. More seriously, these differences are often comparable to the size of the sources of internal variability which some authors infer from these data! Agreement between the datasets is good between 1980 and 2005, however in the 1950s and 1960s ERSST5 is cooler than HadSST3, and the coastal hybrid record is cooler still. There are large differences during World War 2. In the early 20th century the coastal hybrid record is warmer than the others. In the 19th century ERSST5 is the warm outlier. HadSST3 also shows a lower trend than the other datasets of the supposed "hiatus" period (Hausfather et al, 2017).

Comparison of different SST datasetsComparison of HadSST3 (the current version of the UK Met Office dataset), ERSST5 (the current NOAA sea surface temperature dataset), and the coastal hybrid sea surface temperature dataset (from Cowtan et al, 2017). Temperature averages are calculated using common coverage.

Over the past couple of years the Hadley centre have contributed to significant work on the mid 20th century (Carella et al 2018, Davis et al 2018). In particular Carella and colleagues provide a new method for distinguishing between sea surface temperature observations using buckets versus engine room intakes, based on evaluation of the diurnal cycle in the observations. This leads to changes in the inferred observation type in cases where metadata are missing or unreliable, and as a result changes the distribution of observation types in the 1950s and 60s. Improvements have also been made to the estimation of the correction required for different observation types, including the differences between different types of buckets.

These changes, along with corrections to recent temperature observations determined from satellite data and surface and subsurface automated probes, have been incorporated in a new version of the Hadley record, called HadSST4 (Kennedy et al, 2019). The new version is significantly cooler for the period from 1950-1975, and also shows more temperature change on a centennial timescale. When compared to the coastal hybrid temperature record (Figure 2), the big step around 1975 has been completely eliminated, and (more tentatively) temperature change since the 19th century shows better agreement, although there are still large unexplained differences in the early 20th century.

Differences between SST versionsComparison of the current and new versions of the UKMO sea surface temperature data (HadSST3 and HadSST4) to the coastal hybrid temperature record of Cowtan and colleagues (2017).

Where does this leave us? Over the past couple of years I have been recommending that people baseline their temperature comparisons on the period 1981-2010, because there are significant differences between datasets prior to that point. The largest disagreements arising between 1950 and the present have been substantially reduced, providing more flexibility with regard to choice of baseline. Trends in this period, including the supposed "hiatus" period, are also more consistent between datasets. The large changes to the period spanning 1950 to 1975 will change the conclusions of many papers on internal variability in sea surface temperature (which were arguably never well founded). HadSST is no longer a warm outlier on this period: it is now cooler than ERSST and in good agreement with our coastal record. The continuation of ship bias correction right up to the present (first done in ERSST in 2015) brings HadSST into very good agreement with all other SST datasets from the late 1990s on.

The early 20th century is more difficult. Our coastal record suggests that HadSST3 and 4 are too cool in this period (as do many climate model simulations), however ERSST comes to a similar conclusion to HadSST by different means. World War 2 shows very large discrepancies. Assigning observation types and estimating corrections becomes increasingly difficult as the data and metadata become sparser, and the problem is so hard that no-one outside the Hadley team and associates is even attempting it.

I have made available a new version of our infilled land-ocean temperature reconstruction (Cowtan & Way 2014, Richardson et al 2016) using HadSST4 (i.e. the second dataset on this page), and included it in the trend calculator (here and here). Temperature trends over the supposed "hiatus" period have increased. Estimates of temperature change compared to a pre-industrial baseline and of climate sensitivity are increased, however these depend on the longer term features of the records over which there is still substantial disagreement. The new land-ocean temperature record is compared to CMIP5 climate model simulations in Figure 3. While the CMIP5 simulations are expected to overpredict recent warming (because the emissions increases projected in 2005 were too high), the agreement between observations and projections is improved.

Comparison of observations to climate modelsComparison of infilled global temperature observations calculated according to Cowtan and Way (2014) using either HadSST3 or HadSST4 against blended land-ocean temperatures from the CMIP5 RCP85 climate model simulations. (1951-1980 baseline)

Another approach to the problem of reconstructing global temperatures is being led by the National Oceanographic Centre, with the Hadley centre, UEA, Reading, Edinburgh and York as partners. The GloSAT project aims to create a new (diurnal) marine air temperature record stretching back to the 1780s along with land air temperatures for the same period. This will provide more information for the evaluation of sea surface temperature observations, as well as giving a new perspective on the onset of anthropogenic warming in the context of the large volcanic eruptions of the late 18th century.

References



from Skeptical Science https://ift.tt/2LGTuh5

The oceans cover two thirds of the surface of the earth, and so sea surface temperatures form a vital part of our understanding of the impact of human activity on the temperature of the planet. Sea surface temperatures contribute to estimates of global surface temperature change which are widely used in the evaluation of climate models, the estimation of internal modes of climate variability, and the setting of political targets. The ways in which sea surface temperatures have been measured by ships, buoys and satellites have varied much more significantly over time than equipment at weather stations; these changes have to be corrected when evaluating historical temperature change. Differences between different sea surface temperature datasets highlight where some of these corrections are uncertain, however users of temperature data frequently ignore these uncertainties and the effect they may have on their conclusions.

This issue was highlighted in a paper by Kent and colleagues in 2017, which made a call for action both for temperature record providers to make more progress on these issues, and for users to be aware of what the data can and cannot tell us. A number of authors have responded by investigating aspects of the sea surface temperature record (e.g. Hausfather et al 2017, Cowtan et al, 2017, Carella et al 2018, Davis et al 2018). Last week the latest version of the UK Hadley centre sea surface temperature dataset, HadSST4, was released.

The Hadley centre have been at the forefront of the development of sea surface temperature data for many years, providing the only sea record which attempts to reconcile the measurement types of individual observations. A Japanese dataset, COBE-SST2, also uses the Hadley analysis of data corrections in combination with an alternative post-processing algorithm to produce an infilled sea surface temperature reconstruction.

Other datasets apply more coarse grained corrections: NOAA's ERSST (Huang et al, 2017) corrects the gridded ship temperature field on the basis of smoothed differences between water and air temperature measurements, while my own coastal hybrid reconstruction (Cowtan et al, 2017) uses coastal weather stations to estimate a global correction for the combined impact of different types of sea surface temperature observations.

The problem is that these methods lead to different answers (Figure 1), suggesting that the required corrections for the different observations are not yet well understood. More seriously, these differences are often comparable to the size of the sources of internal variability which some authors infer from these data! Agreement between the datasets is good between 1980 and 2005, however in the 1950s and 1960s ERSST5 is cooler than HadSST3, and the coastal hybrid record is cooler still. There are large differences during World War 2. In the early 20th century the coastal hybrid record is warmer than the others. In the 19th century ERSST5 is the warm outlier. HadSST3 also shows a lower trend than the other datasets of the supposed "hiatus" period (Hausfather et al, 2017).

Comparison of different SST datasetsComparison of HadSST3 (the current version of the UK Met Office dataset), ERSST5 (the current NOAA sea surface temperature dataset), and the coastal hybrid sea surface temperature dataset (from Cowtan et al, 2017). Temperature averages are calculated using common coverage.

Over the past couple of years the Hadley centre have contributed to significant work on the mid 20th century (Carella et al 2018, Davis et al 2018). In particular Carella and colleagues provide a new method for distinguishing between sea surface temperature observations using buckets versus engine room intakes, based on evaluation of the diurnal cycle in the observations. This leads to changes in the inferred observation type in cases where metadata are missing or unreliable, and as a result changes the distribution of observation types in the 1950s and 60s. Improvements have also been made to the estimation of the correction required for different observation types, including the differences between different types of buckets.

These changes, along with corrections to recent temperature observations determined from satellite data and surface and subsurface automated probes, have been incorporated in a new version of the Hadley record, called HadSST4 (Kennedy et al, 2019). The new version is significantly cooler for the period from 1950-1975, and also shows more temperature change on a centennial timescale. When compared to the coastal hybrid temperature record (Figure 2), the big step around 1975 has been completely eliminated, and (more tentatively) temperature change since the 19th century shows better agreement, although there are still large unexplained differences in the early 20th century.

Differences between SST versionsComparison of the current and new versions of the UKMO sea surface temperature data (HadSST3 and HadSST4) to the coastal hybrid temperature record of Cowtan and colleagues (2017).

Where does this leave us? Over the past couple of years I have been recommending that people baseline their temperature comparisons on the period 1981-2010, because there are significant differences between datasets prior to that point. The largest disagreements arising between 1950 and the present have been substantially reduced, providing more flexibility with regard to choice of baseline. Trends in this period, including the supposed "hiatus" period, are also more consistent between datasets. The large changes to the period spanning 1950 to 1975 will change the conclusions of many papers on internal variability in sea surface temperature (which were arguably never well founded). HadSST is no longer a warm outlier on this period: it is now cooler than ERSST and in good agreement with our coastal record. The continuation of ship bias correction right up to the present (first done in ERSST in 2015) brings HadSST into very good agreement with all other SST datasets from the late 1990s on.

The early 20th century is more difficult. Our coastal record suggests that HadSST3 and 4 are too cool in this period (as do many climate model simulations), however ERSST comes to a similar conclusion to HadSST by different means. World War 2 shows very large discrepancies. Assigning observation types and estimating corrections becomes increasingly difficult as the data and metadata become sparser, and the problem is so hard that no-one outside the Hadley team and associates is even attempting it.

I have made available a new version of our infilled land-ocean temperature reconstruction (Cowtan & Way 2014, Richardson et al 2016) using HadSST4 (i.e. the second dataset on this page), and included it in the trend calculator (here and here). Temperature trends over the supposed "hiatus" period have increased. Estimates of temperature change compared to a pre-industrial baseline and of climate sensitivity are increased, however these depend on the longer term features of the records over which there is still substantial disagreement. The new land-ocean temperature record is compared to CMIP5 climate model simulations in Figure 3. While the CMIP5 simulations are expected to overpredict recent warming (because the emissions increases projected in 2005 were too high), the agreement between observations and projections is improved.

Comparison of observations to climate modelsComparison of infilled global temperature observations calculated according to Cowtan and Way (2014) using either HadSST3 or HadSST4 against blended land-ocean temperatures from the CMIP5 RCP85 climate model simulations. (1951-1980 baseline)

Another approach to the problem of reconstructing global temperatures is being led by the National Oceanographic Centre, with the Hadley centre, UEA, Reading, Edinburgh and York as partners. The GloSAT project aims to create a new (diurnal) marine air temperature record stretching back to the 1780s along with land air temperatures for the same period. This will provide more information for the evaluation of sea surface temperature observations, as well as giving a new perspective on the onset of anthropogenic warming in the context of the large volcanic eruptions of the late 18th century.

References



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Emory mathematician to present a proof of the Sensitivity Conjecture

Emory mathematician Hao Huang says that the algebraic tool that he developed to tackle the problem "might also have some potential to be applied to other combinatorial and complexity problems important to computer science.”

The Sensitivity Conjecture has stood as one of the most important, and baffling, open problems in theoretical computer science for nearly three decades. It appears to have finally met its match through work by Hao Huang, an assistant professor of mathematics at Emory University.

Huang will present a proof of the Sensitivity Conjecture during the International Conference on Random Structures and Algorithms, set for Zurich, Switzerland, July 15 to 19.

“I’ve been attacking this problem off and on since 2012,” Huang says, “but the key idea emerged for me just about a week ago. I finally identified the right tool to solve it.”

Huang posted the proof on his home page and it soon generated buzz among mathematicians and computer scientists on social media, who have praised its remarkable conciseness and simplicity.

The Sensitivity Conjecture relates to boolean data, which maps information into a true-false, or 1-0 binary. Boolean functions play an important role in complexity theory, as well in the design of circuits and chips for digital computers.

“In mathematics, a boolean function is one of the most basic discrete subjects — just like numbers, graphs or geometric shapes,” Huang explains.

There are many complexity measures of a boolean function, and almost all of them — including the decision-tree complexity, the certificate complexity, the randomized query complexity and many others — are known to be polynomially related. However, there is one unknown case, the so-called sensitivity of a boolean function, which measures how sensitive the function is when changing one input at a time.

In 1994, mathematicians Noam Nisan and Mario Szegedy proposed the Sensitivity Conjecture concerning this unknown case.

“Their conjecture says the sensitivity of a boolean function is also polynomially related to the other measures,” Huang says. “If true, then it would cease to be an outlier and it would join the rest of them.”

Huang developed an algebraic method for proving the conjecture. “I hope this method might also have some potential to be applied to other combinatorial and complexity problems important to computer science,” he says.

The research was supported in part by the Simons Foundation.

from eScienceCommons https://ift.tt/2L3hGed
Emory mathematician Hao Huang says that the algebraic tool that he developed to tackle the problem "might also have some potential to be applied to other combinatorial and complexity problems important to computer science.”

The Sensitivity Conjecture has stood as one of the most important, and baffling, open problems in theoretical computer science for nearly three decades. It appears to have finally met its match through work by Hao Huang, an assistant professor of mathematics at Emory University.

Huang will present a proof of the Sensitivity Conjecture during the International Conference on Random Structures and Algorithms, set for Zurich, Switzerland, July 15 to 19.

“I’ve been attacking this problem off and on since 2012,” Huang says, “but the key idea emerged for me just about a week ago. I finally identified the right tool to solve it.”

Huang posted the proof on his home page and it soon generated buzz among mathematicians and computer scientists on social media, who have praised its remarkable conciseness and simplicity.

The Sensitivity Conjecture relates to boolean data, which maps information into a true-false, or 1-0 binary. Boolean functions play an important role in complexity theory, as well in the design of circuits and chips for digital computers.

“In mathematics, a boolean function is one of the most basic discrete subjects — just like numbers, graphs or geometric shapes,” Huang explains.

There are many complexity measures of a boolean function, and almost all of them — including the decision-tree complexity, the certificate complexity, the randomized query complexity and many others — are known to be polynomially related. However, there is one unknown case, the so-called sensitivity of a boolean function, which measures how sensitive the function is when changing one input at a time.

In 1994, mathematicians Noam Nisan and Mario Szegedy proposed the Sensitivity Conjecture concerning this unknown case.

“Their conjecture says the sensitivity of a boolean function is also polynomially related to the other measures,” Huang says. “If true, then it would cease to be an outlier and it would join the rest of them.”

Huang developed an algebraic method for proving the conjecture. “I hope this method might also have some potential to be applied to other combinatorial and complexity problems important to computer science,” he says.

The research was supported in part by the Simons Foundation.

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Do organic crystals create ‘bathtub rings’ around Titan’s lakes and seas?

Green globe with irregular dark green, orange, and yellow markings in upper part.

Infrared view of seas and lakes in Titan’s northern hemisphere, taken by Cassini in 2014. Sunlight can be seen glinting off the southern part of Titan’s largest sea, Kraken Mare. Scientists now think that “bathtub rings” around the edges of the seas and lakes are composed of organic crystals. Image via NASA/JPL-Caltech/University of Arizona/University of Idaho/AGU 100.

Saturn’s moon Titan is the only other body in the solar system besides Earth known to have liquids on its surface. These rains, rivers, lakes and seas look very much like those on Earth, but are composed of liquid methane and ethane (hydrocarbons) instead of water. Now, scientists have found another way in which they might differ from their earthly counterparts: the shorelines of the lakes and seas might be encrusted with “bathtub rings” composed of organic crystals not found on Earth.

The new research was published in a new paper and presented on June 24 at the 2019 Astrobiology Science Conference (AbSciCon 2019) in Bellevue, Washington.

From the new paper:

We have discovered a third molecular mineral that is stable in the same conditions present on the surface of Titan, a moon of Saturn. This molecular mineral is made up of acetylene and butane, two organic molecules that are produced in Titan’s atmosphere and fall down onto the surface. We call these ‘molecular minerals’ because they behave just like minerals do here on Earth, but instead of being made up of things like carbonates or silicates, they are made up of organic molecules. The two previous molecular minerals we discovered were made up of benzene and ethane, and acetylene and ammonia. This most recent one is probably much more abundant on Titan’s surface, as both acetylene and butane are believed to be very common there. In particular, we think the ‘bathtub rings’ around Titan’s lakes might be made up of this material, because acetylene and butane both dissolve well in liquid methane and ethane compared to other molecules.

Steep mountains surround reddish lake under dim, pale tan sky.

Artist’s concept of a hydrocarbon lake on Titan as seen from the ground. Image via Steven Hobbs (Brisbane, Queensland, Australia/NASA).

The intriguing results come from laboratory tests where Titan-like conditions were recreated. The scientists found compounds and minerals that do not exist on Earth, and one co-crystal was made of solid acetylene and butane, which do exist on Earth, but only as gases. Titan is so cold, however, that acetylene and butane will freeze solid and combine to form crystals.

So how did the scientists create Titan-like conditions in a laboratory on Earth? Titan is extremely cold, about -290 degrees Fahrenheit (-179 degrees Celsius), so they used a custom-built cryostat, an apparatus that keeps things cold. Titan’s atmosphere is mostly nitrogen, like Earth’s, so next they filled the cryostat with liquid nitrogen. But they needed the nitrogen to be a gas, like on Titan, so they warmed the chamber slightly. Methane and ethane were then added, which are also very common on Titan. They are both in liquid form on the moon, in the rain, rivers, lakes and seas. The result was a hydrocarbon-rich “soup.”

Dark blue irregular shapes with labels against a variegated tan background.

Map of Titan’s seas and lakes in the northern hemisphere. Image via JPL-Caltech/NASA/ASI/USGS/EarthSky.

Yellowish scene of hazy sky and landscape covered in rounded, irregular rocks.

The surface of Titan as seen by the Huygens lander in 2005. Huygens found damp sand when it landed near an evaporated riverbed. The liquid was methane/ethane, but the “rocks” turned out to be composed of solid water ice. Image via ESA/NASA/University of Arizona/EarthSky.

Benzene crystals were the first to be seen forming in this soup. Benzene is found in gasoline on Earth and is a snowflake-shaped molecule made out of a hexagonal ring of carbon atoms. But something else surprising happened in the simulated Titan conditions: the benzene molecules rearranged themselves in such a way that they allowed ethane molecules inside them, creating a co-crystal. The researchers also later discovered an acetylene and butane co-crystal as well, which is thought to probably be more common on Titan.

It is the acetylene and butane co-crystals that likely create the bathtub rings – evaporated minerals – around the edges of the lakes and seas. The minerals would be dropped out on the surface as the liquid hydrocarbons started to evaporate. Some lakes were seen on Titan by the Cassini spacecraft when they were full of liquid, and at other times when they had partially evaporated. This evaporation process is similar to how salts can form crusts around the edges of lakes and seas on Earth.

The bathtub rings on Titan are suspected to exist based on evidence from Cassini, but haven’t been fully confirmed yet, as noted by Morgan Cable at the Jet Propulsion Laboratory:

We don’t know yet if we have these bathtub rings … It’s hard to see through Titan’s hazy atmosphere.

Wide white band surrounding whitish lake under a brilliant blue sky.

An acidic salt lake south of Beacon, West Australia. The salt encrustations around its edges are thought to be similar to the bathtub rings around the edges of lakes and seas on Titan. Image via Suzanne M. Rea/ResearchGate.

Titan’s rivers, lakes and seas, mostly near the north pole, give this moon an eerily Earth-like appearance. There is also methane rain and massive sand dunes near the equator, like in deserts on Earth, but composed of hydrocarbon particles. The thick, hazy atmosphere obscures the ground from view from above, but Cassini was able to use use radar to see surface features. The Huygens probe, part of the Cassini mission, also sent back the first-ever photos from Titan’s surface in 2005, showing an evaporated riverbed with “rocks” composed of solid water ice. Beneath all of that, out of view, is a subsurface water ocean. Titan may look a lot like Earth in many ways, but in terms of composition, it is a distinctly alien world.

Unfortunately, Cassini’s mission ended in late 2017, so further observations of the bathtub rings will have to wait until a future mission returns to Titan. Probes that could float or swim in one of the lakes or seas have been proposed, but are still just on the drawing boards right now. However, NASA’s new Dragonfly mission, just officially announced last week, will send a drone-like rotorcraft to fly through Titan’s skies, making numerous landings at different locations of interest. Dragonfly is scheduled to launch in 2026 and land in 2034. Exciting!

Bottom line: By simulating Titan’s conditions in a laboratory on Earth, scientists have found that unusual forms of organic crystals may create bathtub rings around the edges of the moon’s lakes and seas.

Source: The Acetylene-Butane Co-Crystal: A Potentially Abundant Molecular Mineral on Titan

Via AGU 100



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Green globe with irregular dark green, orange, and yellow markings in upper part.

Infrared view of seas and lakes in Titan’s northern hemisphere, taken by Cassini in 2014. Sunlight can be seen glinting off the southern part of Titan’s largest sea, Kraken Mare. Scientists now think that “bathtub rings” around the edges of the seas and lakes are composed of organic crystals. Image via NASA/JPL-Caltech/University of Arizona/University of Idaho/AGU 100.

Saturn’s moon Titan is the only other body in the solar system besides Earth known to have liquids on its surface. These rains, rivers, lakes and seas look very much like those on Earth, but are composed of liquid methane and ethane (hydrocarbons) instead of water. Now, scientists have found another way in which they might differ from their earthly counterparts: the shorelines of the lakes and seas might be encrusted with “bathtub rings” composed of organic crystals not found on Earth.

The new research was published in a new paper and presented on June 24 at the 2019 Astrobiology Science Conference (AbSciCon 2019) in Bellevue, Washington.

From the new paper:

We have discovered a third molecular mineral that is stable in the same conditions present on the surface of Titan, a moon of Saturn. This molecular mineral is made up of acetylene and butane, two organic molecules that are produced in Titan’s atmosphere and fall down onto the surface. We call these ‘molecular minerals’ because they behave just like minerals do here on Earth, but instead of being made up of things like carbonates or silicates, they are made up of organic molecules. The two previous molecular minerals we discovered were made up of benzene and ethane, and acetylene and ammonia. This most recent one is probably much more abundant on Titan’s surface, as both acetylene and butane are believed to be very common there. In particular, we think the ‘bathtub rings’ around Titan’s lakes might be made up of this material, because acetylene and butane both dissolve well in liquid methane and ethane compared to other molecules.

Steep mountains surround reddish lake under dim, pale tan sky.

Artist’s concept of a hydrocarbon lake on Titan as seen from the ground. Image via Steven Hobbs (Brisbane, Queensland, Australia/NASA).

The intriguing results come from laboratory tests where Titan-like conditions were recreated. The scientists found compounds and minerals that do not exist on Earth, and one co-crystal was made of solid acetylene and butane, which do exist on Earth, but only as gases. Titan is so cold, however, that acetylene and butane will freeze solid and combine to form crystals.

So how did the scientists create Titan-like conditions in a laboratory on Earth? Titan is extremely cold, about -290 degrees Fahrenheit (-179 degrees Celsius), so they used a custom-built cryostat, an apparatus that keeps things cold. Titan’s atmosphere is mostly nitrogen, like Earth’s, so next they filled the cryostat with liquid nitrogen. But they needed the nitrogen to be a gas, like on Titan, so they warmed the chamber slightly. Methane and ethane were then added, which are also very common on Titan. They are both in liquid form on the moon, in the rain, rivers, lakes and seas. The result was a hydrocarbon-rich “soup.”

Dark blue irregular shapes with labels against a variegated tan background.

Map of Titan’s seas and lakes in the northern hemisphere. Image via JPL-Caltech/NASA/ASI/USGS/EarthSky.

Yellowish scene of hazy sky and landscape covered in rounded, irregular rocks.

The surface of Titan as seen by the Huygens lander in 2005. Huygens found damp sand when it landed near an evaporated riverbed. The liquid was methane/ethane, but the “rocks” turned out to be composed of solid water ice. Image via ESA/NASA/University of Arizona/EarthSky.

Benzene crystals were the first to be seen forming in this soup. Benzene is found in gasoline on Earth and is a snowflake-shaped molecule made out of a hexagonal ring of carbon atoms. But something else surprising happened in the simulated Titan conditions: the benzene molecules rearranged themselves in such a way that they allowed ethane molecules inside them, creating a co-crystal. The researchers also later discovered an acetylene and butane co-crystal as well, which is thought to probably be more common on Titan.

It is the acetylene and butane co-crystals that likely create the bathtub rings – evaporated minerals – around the edges of the lakes and seas. The minerals would be dropped out on the surface as the liquid hydrocarbons started to evaporate. Some lakes were seen on Titan by the Cassini spacecraft when they were full of liquid, and at other times when they had partially evaporated. This evaporation process is similar to how salts can form crusts around the edges of lakes and seas on Earth.

The bathtub rings on Titan are suspected to exist based on evidence from Cassini, but haven’t been fully confirmed yet, as noted by Morgan Cable at the Jet Propulsion Laboratory:

We don’t know yet if we have these bathtub rings … It’s hard to see through Titan’s hazy atmosphere.

Wide white band surrounding whitish lake under a brilliant blue sky.

An acidic salt lake south of Beacon, West Australia. The salt encrustations around its edges are thought to be similar to the bathtub rings around the edges of lakes and seas on Titan. Image via Suzanne M. Rea/ResearchGate.

Titan’s rivers, lakes and seas, mostly near the north pole, give this moon an eerily Earth-like appearance. There is also methane rain and massive sand dunes near the equator, like in deserts on Earth, but composed of hydrocarbon particles. The thick, hazy atmosphere obscures the ground from view from above, but Cassini was able to use use radar to see surface features. The Huygens probe, part of the Cassini mission, also sent back the first-ever photos from Titan’s surface in 2005, showing an evaporated riverbed with “rocks” composed of solid water ice. Beneath all of that, out of view, is a subsurface water ocean. Titan may look a lot like Earth in many ways, but in terms of composition, it is a distinctly alien world.

Unfortunately, Cassini’s mission ended in late 2017, so further observations of the bathtub rings will have to wait until a future mission returns to Titan. Probes that could float or swim in one of the lakes or seas have been proposed, but are still just on the drawing boards right now. However, NASA’s new Dragonfly mission, just officially announced last week, will send a drone-like rotorcraft to fly through Titan’s skies, making numerous landings at different locations of interest. Dragonfly is scheduled to launch in 2026 and land in 2034. Exciting!

Bottom line: By simulating Titan’s conditions in a laboratory on Earth, scientists have found that unusual forms of organic crystals may create bathtub rings around the edges of the moon’s lakes and seas.

Source: The Acetylene-Butane Co-Crystal: A Potentially Abundant Molecular Mineral on Titan

Via AGU 100



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Will planetary low tide force regular sunspot sync-ups?

A shimmery yellow circle on a black background with many fine white arc lines on it.

An ultraviolet image of the sun, overlaid with a map of its magnetic field lines. Image via NASA/SDO/AIA/LMSAL.

By Kimberly M. S. Cartier, reprinted with permission from Eos.

For more than 1,000 years, the number of sunspots hit a minimum within a few years of a major planetary alignment. A recent study showed that tides created by this alignment every 11 years are strong enough to tug on material near the sun’s surface and synchronize localized changes in its magnetic field.

Frank Stefani, lead author of the study, told Eos.

We noticed from historical data that there is an astonishing degree of regularity in the sunspot cycle.

Stefani is a fluid dynamics research fellow at Helmholtz-Zentrum Dresden-Rossendorf in Dresden, Germany. He said:

We definitely have a clocked process. But then the question was, What is the clock?

The study expands upon the commonly accepted model for the solar dynamo and supports a long-held theory that planetary configurations are responsible for the sunspot cycle and magnetic solar cycle.

Wound, Twisted, and Unstable

As a giant spinning ball of plasma, the sun’s magnetic field is extremely complicated. Its magnetic field lines start as parallel lines running from the north to the south pole. But because the sun rotates faster at its equator than at its poles, those pole-to-pole magnetic field lines slowly wind and wrap around the sun, stretching like taffy from the middle of the line to become horizontal.

Line drawing of circle with parallel lines on it, two with vertical twists.

A simplified schematic of a single magnetic field line as it wraps around the sun (omega effect) and then twists upon itself (alpha effect). The arrows indicate the direction that solar material moves as it drags the field line with it. Image via NASA/MSFC.

On top of the rotational motion of solar plasma, convection moves material from the equator to the poles and back again. That twists the field lines around each other into loops and spirals.

The winding and twisting of the sun’s magnetic field lines are described by the alpha-omega dynamo model. In that model, alpha represents the twisting, and omega represents the wrapping. Tangled field lines can create instabilities in the local magnetic field and cause sunspots, flares, or mass ejections.

This model is the commonly accepted explanation for the behavior of the sun’s magnetic field, but it’s not perfect, Stefani explained. It predicts that the instabilities’ twistedness will oscillate randomly every few years. But the model can’t explain why the number of sunspots waxes and wanes on a roughly 11-year cycle or why the sun’s magnetic field flips polarity every 22 years.

Low Tide, Low Activity

Another solar system phenomenon happens every 11 years: Venus, Earth, and Jupiter align in their orbits. These three planets have the strongest tidal effect on the sun, the first two because of their proximity to the sun and the third because of its mass. Past observational studies have shown that minima in the sunspot cycle have occurred within a few years of this alignment for the past 1,000 years or so. Stefani said:

If you look at the trend, it has an amazing parallelism.

The researchers wanted to test whether the planetary alignment could influence the sun’s alpha effect and force an interplanetary low tide at regular intervals. The team started with a standard alpha-omega dynamo model and added a small tidal tug to the alpha effect every 11 years to simulate the alignment. Stefani explained:

Our dynamo model is not a completely new one. We’re really building on the old-fashioned, or conventional, alpha-omega dynamo.

The simulation showed that even a weak tidal tug of 1 meter [1 yard] per second every 11 years forced unstable magnetic twists to pulse with that same period. The simulated dynamo’s polarity oscillated with a 22-year period just like the real solar dynamo. Stefani said:

With a little bit of this periodic alpha, we can indeed synchronize the dynamo period to 22 years [with] planetary forcing.

Because those magnetic instabilities are connected with solar activity, the researchers argue, this synchronization could also suppress (or generate) sunspots across the sun at roughly the same time – in other words, the sunspot cycle. The team published these results in Solar Physics in late May 2019.

A Counterintuitive Result?

Steve Tobias is a solar dynamo researcher at the University of Leeds in the United Kingdom who was not involved with this research. He said:

This is an intriguing paper.

Tobias argued that the combined planetary tides are too weak to directly set the length of the solar cycle. Plasma dynamics deep within the sun are the more likely cause, he told Eos.

Nevertheless, he said, this study

… seems to show that even a tiny amount of forcing from tidal processes can resonantly synchronize the cycle. This counterintuitive result should be explored further by investigating the behavior of proxies for solar activity such as the production rates of isotopes of beryllium deposited in ice cores.

It’s possible that other planetary systems might have tidally dominant planets that resonate with their suns like ours do, Stefani said, but it’s not likely that we’ll be able to prove it. For most stars, he said:

… we have observations going back about 40 years. And people are happy if they can identify two or three or four periods. Only for our Sun do we have all the historical observations. We have beryllium data. We can go back for thousands of years.

Our sun is quite an ordinary star, but it is quite special in that sense.

Bottom line: New research suggests that a regular alignment of the planets makes a strong enough tug to regulate the sun’s 11- and 22-year cycles.

Via Eos



from EarthSky https://ift.tt/2FU5dFj
A shimmery yellow circle on a black background with many fine white arc lines on it.

An ultraviolet image of the sun, overlaid with a map of its magnetic field lines. Image via NASA/SDO/AIA/LMSAL.

By Kimberly M. S. Cartier, reprinted with permission from Eos.

For more than 1,000 years, the number of sunspots hit a minimum within a few years of a major planetary alignment. A recent study showed that tides created by this alignment every 11 years are strong enough to tug on material near the sun’s surface and synchronize localized changes in its magnetic field.

Frank Stefani, lead author of the study, told Eos.

We noticed from historical data that there is an astonishing degree of regularity in the sunspot cycle.

Stefani is a fluid dynamics research fellow at Helmholtz-Zentrum Dresden-Rossendorf in Dresden, Germany. He said:

We definitely have a clocked process. But then the question was, What is the clock?

The study expands upon the commonly accepted model for the solar dynamo and supports a long-held theory that planetary configurations are responsible for the sunspot cycle and magnetic solar cycle.

Wound, Twisted, and Unstable

As a giant spinning ball of plasma, the sun’s magnetic field is extremely complicated. Its magnetic field lines start as parallel lines running from the north to the south pole. But because the sun rotates faster at its equator than at its poles, those pole-to-pole magnetic field lines slowly wind and wrap around the sun, stretching like taffy from the middle of the line to become horizontal.

Line drawing of circle with parallel lines on it, two with vertical twists.

A simplified schematic of a single magnetic field line as it wraps around the sun (omega effect) and then twists upon itself (alpha effect). The arrows indicate the direction that solar material moves as it drags the field line with it. Image via NASA/MSFC.

On top of the rotational motion of solar plasma, convection moves material from the equator to the poles and back again. That twists the field lines around each other into loops and spirals.

The winding and twisting of the sun’s magnetic field lines are described by the alpha-omega dynamo model. In that model, alpha represents the twisting, and omega represents the wrapping. Tangled field lines can create instabilities in the local magnetic field and cause sunspots, flares, or mass ejections.

This model is the commonly accepted explanation for the behavior of the sun’s magnetic field, but it’s not perfect, Stefani explained. It predicts that the instabilities’ twistedness will oscillate randomly every few years. But the model can’t explain why the number of sunspots waxes and wanes on a roughly 11-year cycle or why the sun’s magnetic field flips polarity every 22 years.

Low Tide, Low Activity

Another solar system phenomenon happens every 11 years: Venus, Earth, and Jupiter align in their orbits. These three planets have the strongest tidal effect on the sun, the first two because of their proximity to the sun and the third because of its mass. Past observational studies have shown that minima in the sunspot cycle have occurred within a few years of this alignment for the past 1,000 years or so. Stefani said:

If you look at the trend, it has an amazing parallelism.

The researchers wanted to test whether the planetary alignment could influence the sun’s alpha effect and force an interplanetary low tide at regular intervals. The team started with a standard alpha-omega dynamo model and added a small tidal tug to the alpha effect every 11 years to simulate the alignment. Stefani explained:

Our dynamo model is not a completely new one. We’re really building on the old-fashioned, or conventional, alpha-omega dynamo.

The simulation showed that even a weak tidal tug of 1 meter [1 yard] per second every 11 years forced unstable magnetic twists to pulse with that same period. The simulated dynamo’s polarity oscillated with a 22-year period just like the real solar dynamo. Stefani said:

With a little bit of this periodic alpha, we can indeed synchronize the dynamo period to 22 years [with] planetary forcing.

Because those magnetic instabilities are connected with solar activity, the researchers argue, this synchronization could also suppress (or generate) sunspots across the sun at roughly the same time – in other words, the sunspot cycle. The team published these results in Solar Physics in late May 2019.

A Counterintuitive Result?

Steve Tobias is a solar dynamo researcher at the University of Leeds in the United Kingdom who was not involved with this research. He said:

This is an intriguing paper.

Tobias argued that the combined planetary tides are too weak to directly set the length of the solar cycle. Plasma dynamics deep within the sun are the more likely cause, he told Eos.

Nevertheless, he said, this study

… seems to show that even a tiny amount of forcing from tidal processes can resonantly synchronize the cycle. This counterintuitive result should be explored further by investigating the behavior of proxies for solar activity such as the production rates of isotopes of beryllium deposited in ice cores.

It’s possible that other planetary systems might have tidally dominant planets that resonate with their suns like ours do, Stefani said, but it’s not likely that we’ll be able to prove it. For most stars, he said:

… we have observations going back about 40 years. And people are happy if they can identify two or three or four periods. Only for our Sun do we have all the historical observations. We have beryllium data. We can go back for thousands of years.

Our sun is quite an ordinary star, but it is quite special in that sense.

Bottom line: New research suggests that a regular alignment of the planets makes a strong enough tug to regulate the sun’s 11- and 22-year cycles.

Via Eos



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