News digest – cancer survival, cervical screening, immunotherapy on the NHS and US targeted drug approval

Cancer survival in England still lagging behind the best

England hasn’t closed the gap on countries with the best cancer survival figures, despite improvements in cancer care and survival over the last 20 years. BBC News covered the new report, which warned that a “radical rethink” was required to help close the gap. The report highlights the need to diagnose more cancers earlier, as our news report details.

Immunotherapy drug now an option for some NHS patients with advanced skin cancer

The immunotherapy drug nivolumab (Opdivo) will now be an option for some patients with advanced melanoma skin cancer on the NHS in England. The drug works by boosting the immune system’s ability to kill cancer cells and will be given after surgery to help target any cancer cells left behind. Our news report has the details.

1 in 10 bowel cancer patients start treatment over a year after first noticing symptoms

Researchers found that men and women in Wales took the longest to contact their doctor after noticing a symptom or health change. And they also had the longest time from first noticing a change to starting treatment, which on average took 168 days. This compared to 145 days in England, 138 days in Northern Ireland and 120 days in Scotland. Our press release and ITV Wales have the story.

Targeted drug given green light for some NHS liver cancer patients

A targeted cancer drug will now be available for some adults with advanced liver cancer on the NHS in England and Wales. Regorafenib (Stivarga) was initially turned down by the National Institute for Health and Care Excellence (NICE) but will now be an option for a small group of patients whose livers are still working, but who can’t have surgery and have already been treated with a drug called sorafenib. Our news report has the story.

Cervical screening take-up continues to fall

More than a million women a year aren’t taking up the offer of cervical screening in England, reports The Sun. Women aged 25 to 64 are invited to cervical screening every 3 to 5 years, but 3 in 10 women aren’t attending, according to new figures.

How will Brexit affect the NHS?

BBC News take a look at the impact Brexit could have on the NHS, asking: will the NHS have enough staff, and will we run out of medicines?

Building a ‘Google Earth’ of cancer

The Evening Standard spoke to Cancer Research UK-funded chemist Professor Josephine Bunch, who’s leading one of our most ambitious Grand Challenge research projects. Bunch and her team are working to create personalised 3D maps of tumours. Our blog post explains how this might help improve cancer diagnosis and treatment in the future.

Rare cancer linked to textured breast implant

Textured breast implants have been linked to an increased risk of developing a rare cancer called anaplastic large cell lymphoma. The Guardian and BBC News covered the news, which was triggered after French surgeons were advised to stop using this type of implant by the health regulator, ANSM, while the link is being investigated. Any risks associated with this type of implant are still unclear but the UKMedicines and Healthcare products Regulatory Agency (MHRA) have estimated the risk of developing this rare cancer is around 1 in 24,000 women with implants will develop the cancer.

Cancer survival in Wales worse in poorer areas

New NHS figures reveal a growing gap between cancer survival in people living in deprived parts of Wales and those in richer areas, reports BBC News. While the number of cancer deaths have fallen in all regions between 2001 and 2017, rates have not fallen as steeply in the most deprived areas.

And finally

A new drug that can treat cancers fuelled by a rare gene fault no matter where they grow in the body has been granted accelerated approval by the US Food and Drug Administration. Larotrectinib (Vitrakvi) targets a rare gene fault that occurs in less than 1 in 100 tumours. It becomes the second treatment to be approved based on a molecular ‘fingerprint’ rather than where the cancer grows. The drug is also being considered for a licence in Europe, with a decision anticipated in 2019. NBC News covered the approval and our news report has a rundown of the latest clinical trial results.

Katie 



from Cancer Research UK – Science blog https://ift.tt/2PaKr6b

Cancer survival in England still lagging behind the best

England hasn’t closed the gap on countries with the best cancer survival figures, despite improvements in cancer care and survival over the last 20 years. BBC News covered the new report, which warned that a “radical rethink” was required to help close the gap. The report highlights the need to diagnose more cancers earlier, as our news report details.

Immunotherapy drug now an option for some NHS patients with advanced skin cancer

The immunotherapy drug nivolumab (Opdivo) will now be an option for some patients with advanced melanoma skin cancer on the NHS in England. The drug works by boosting the immune system’s ability to kill cancer cells and will be given after surgery to help target any cancer cells left behind. Our news report has the details.

1 in 10 bowel cancer patients start treatment over a year after first noticing symptoms

Researchers found that men and women in Wales took the longest to contact their doctor after noticing a symptom or health change. And they also had the longest time from first noticing a change to starting treatment, which on average took 168 days. This compared to 145 days in England, 138 days in Northern Ireland and 120 days in Scotland. Our press release and ITV Wales have the story.

Targeted drug given green light for some NHS liver cancer patients

A targeted cancer drug will now be available for some adults with advanced liver cancer on the NHS in England and Wales. Regorafenib (Stivarga) was initially turned down by the National Institute for Health and Care Excellence (NICE) but will now be an option for a small group of patients whose livers are still working, but who can’t have surgery and have already been treated with a drug called sorafenib. Our news report has the story.

Cervical screening take-up continues to fall

More than a million women a year aren’t taking up the offer of cervical screening in England, reports The Sun. Women aged 25 to 64 are invited to cervical screening every 3 to 5 years, but 3 in 10 women aren’t attending, according to new figures.

How will Brexit affect the NHS?

BBC News take a look at the impact Brexit could have on the NHS, asking: will the NHS have enough staff, and will we run out of medicines?

Building a ‘Google Earth’ of cancer

The Evening Standard spoke to Cancer Research UK-funded chemist Professor Josephine Bunch, who’s leading one of our most ambitious Grand Challenge research projects. Bunch and her team are working to create personalised 3D maps of tumours. Our blog post explains how this might help improve cancer diagnosis and treatment in the future.

Rare cancer linked to textured breast implant

Textured breast implants have been linked to an increased risk of developing a rare cancer called anaplastic large cell lymphoma. The Guardian and BBC News covered the news, which was triggered after French surgeons were advised to stop using this type of implant by the health regulator, ANSM, while the link is being investigated. Any risks associated with this type of implant are still unclear but the UKMedicines and Healthcare products Regulatory Agency (MHRA) have estimated the risk of developing this rare cancer is around 1 in 24,000 women with implants will develop the cancer.

Cancer survival in Wales worse in poorer areas

New NHS figures reveal a growing gap between cancer survival in people living in deprived parts of Wales and those in richer areas, reports BBC News. While the number of cancer deaths have fallen in all regions between 2001 and 2017, rates have not fallen as steeply in the most deprived areas.

And finally

A new drug that can treat cancers fuelled by a rare gene fault no matter where they grow in the body has been granted accelerated approval by the US Food and Drug Administration. Larotrectinib (Vitrakvi) targets a rare gene fault that occurs in less than 1 in 100 tumours. It becomes the second treatment to be approved based on a molecular ‘fingerprint’ rather than where the cancer grows. The drug is also being considered for a licence in Europe, with a decision anticipated in 2019. NBC News covered the approval and our news report has a rundown of the latest clinical trial results.

Katie 



from Cancer Research UK – Science blog https://ift.tt/2PaKr6b

December guide to the bright planets

It’ll be tough to catch the slender crescent moon with the planet Mercury before sunrise December 5. But some of EarthSky’s eagle-eyed observers have surprised us before and may surprise us again! Read more.

Click the name of a planet to learn more about its visibility in December 2018: Venus, Jupiter, Saturn, Mars and Mercury

The 2019 lunar calendars are here! Order yours before they’re gone. Makes a great gift.

Venus is the brightest planet, beaming mightily the east before sunrise. As December 2018 begins, Venus is shining at greatest brilliancy, its brightest for this morning apparition. Although Venus will remain a fixture of the morning sky until mid-August 2019, it’ll grow dimmer, by a bit, after early December. Even so, as always, Venus will rank as the 3rd-brightest celestial body, after the sun and moon!

The waning crescent moon will join Venus in the morning sky for several days, centered on or near December 3. If you’re up before dawn, you can also see the stars Arcturus and Spica accompanying the moon and the queen planet, as depicted on the sky chart above.

At mid-northern latitudes, Venus rises about 3 1/2 hours before sunrise throughout December.

At temperate latitudes in the Southern Hemisphere, Venus rises about two hours before sunup in early December. By the month’s end, that’ll increase to about 3 hours.

In mid-December 2018, look extra hard with the unaided eye or binoculars, and you just might spot the planet Jupiter near the horizon, and on line with Venus and Mercury. Read more.

Jupiter is the 2nd-brightest planet, after Venus. This planet exited the evening sky, and entered the morning sky, in late November. In the first week or two of December, Jupiter rises only a little while before the sun. It’ll be hard to see in the glare of morning twilight.

Jupiter will become easier to see before sunrise around mid-December, when it rises an hour or so before the sun. Around this time, Mercury reaches its greatest western (morning) elongation of 21 degrees from the rising sun. Because Mercury will rise before Jupiter does in mid-December, an imaginary line from Venus through Mercury may enable you to locate Jupiter near the horizon. See the above sky chart.

After mid-December, Jupiter will climb upward toward Mercury, as Mercury is sinking downward, toward Jupiter. Circle December 21 on your calendar, and watch for these two worlds to meet up for a close-knit conjunction. See the sky chart below.

Mercury and Jupiter are in conjunction on December 21, 2018. Very conveniently, these two worlds will easily fit within a single binocular field of view. Read more.

Jupiter rapidly climbs out of the glare of sunrise, coming up a solid two hours before the sun by the month’s end from most places worldwide. Mercury, though sinking sunward, will still rise a good hour before the sun on the last day of 2018. So, as the year draws to a close, watch for picturesque line-up of the waning crescent moon with Venus, Jupiter and Mercury about an hour before sunrise on December 31, as shown on the sky chart below.

On the last morning of the year – December 31, 2018 – watch for the moon to line up with the planets Venus, Jupiter and Mercury. Read more.

Mars and Saturn are the only two bright planets to appear the December 2018 evening sky – though Saturn, for the most part, only nominally so. Saturn sinks closer and closer to the sunset throughout December, and by mid-December will set too soon after the sun to be visible. Your best chance of spotting Saturn may be at dusk/nightfall on December 8 and 9, when the young waxing crescent moon swings rather close to Saturn on the sky’s dome. See the sky chart below.

Let the waxing crescent moon help guide your eye to the planet Saturn in December 2018. Saturn will disappear from the evening sky soon thereafter. Read more.

Fortunately, Mars remains bright and beautiful, shining more brilliantly than a 1st-magnitude star throughout December 2018. In December, Mars transits – reaches its highest point in the sky – at dusk in the Northern Hemisphere, yet before sunset in the Southern Hemisphere. Best of all, Mars stays out till around midnight in both the Northern and Southern Hemispheres.

Click here for a recommended sky almanac providing you with the transit times for Mars.

Watch for the moon to be in the vicinity of Mars for several evenings, centered on or near December 14. Fortunately, the moon will set before the peak hours of the Geminid meteor shower, centered around 2 in the morning on December 13 and 14. See the sky chart below.

On the expected peak night of the Geminids, the moon will be close to Mars on the sky’s dome. Mars’ setting at late night preludes the Geminid’s most prolific display of streaking meteors. Read more.

Saturn will swing over to the morning sky in January 2019, leaving Mars as the only bright planet to adorn the January 2019 evening sky.

Mercury, the innermost planet of the solar system, is a morning planet all month long in December 2018. Mercury might become visible before sunrise by the end of the first week of December. Look for Mercury beneath Venus, as shown on the sky chart below. By mid-December, Mercury rises about 90 minutes before the sun at mid-northern latitudes; from temperate latitudes in the Southern Hemisphere, it’s more like 75 minutes before sunrise. The crowning moment will come on the solstice, when Mercury and Jupiter have their conjunction on December 21.

Let Venus help guide your eye to Mercury .Venus rises in the predawn hours whereas Mercury follows Venus into the morning sky as nighttime gives way to morning dawn. Read more.

What do we mean by bright planet? By bright planet, we mean any solar system planet that is easily visible without an optical aid and that has been watched by our ancestors since time immemorial. In their outward order from the sun, the five bright planets are Mercury, Venus, Mars, Jupiter and Saturn. These planets actually do appear bright in our sky. They are typically as bright as – or brighter than – the brightest stars. Plus, these relatively nearby worlds tend to shine with a steadier light than the distant, twinkling stars. You can spot them, and come to know them as faithful friends, if you try.

Skywatcher, by Predrag Agatonovic.

Bottom line: In December 2018, Mars shines in the evening sky all month long. Saturn disappears in the sunset glare by about mid-month. Venus lights up the eastern sky before sunrise all month. Mercury and Jupiter join Venus in the morning sky around mid-December. Click here for recommended almanacs; they can help you know when the planets rise, transit and set in your sky.

Don’t miss anything. Subscribe to EarthSky News by email

Visit EarthSky’s Best Places to Stargaze, and recommend a place we can all enjoy. Zoom out for worldwide map.

Help EarthSky keep going! Donate now.



from EarthSky https://ift.tt/1YD00CF

It’ll be tough to catch the slender crescent moon with the planet Mercury before sunrise December 5. But some of EarthSky’s eagle-eyed observers have surprised us before and may surprise us again! Read more.

Click the name of a planet to learn more about its visibility in December 2018: Venus, Jupiter, Saturn, Mars and Mercury

The 2019 lunar calendars are here! Order yours before they’re gone. Makes a great gift.

Venus is the brightest planet, beaming mightily the east before sunrise. As December 2018 begins, Venus is shining at greatest brilliancy, its brightest for this morning apparition. Although Venus will remain a fixture of the morning sky until mid-August 2019, it’ll grow dimmer, by a bit, after early December. Even so, as always, Venus will rank as the 3rd-brightest celestial body, after the sun and moon!

The waning crescent moon will join Venus in the morning sky for several days, centered on or near December 3. If you’re up before dawn, you can also see the stars Arcturus and Spica accompanying the moon and the queen planet, as depicted on the sky chart above.

At mid-northern latitudes, Venus rises about 3 1/2 hours before sunrise throughout December.

At temperate latitudes in the Southern Hemisphere, Venus rises about two hours before sunup in early December. By the month’s end, that’ll increase to about 3 hours.

In mid-December 2018, look extra hard with the unaided eye or binoculars, and you just might spot the planet Jupiter near the horizon, and on line with Venus and Mercury. Read more.

Jupiter is the 2nd-brightest planet, after Venus. This planet exited the evening sky, and entered the morning sky, in late November. In the first week or two of December, Jupiter rises only a little while before the sun. It’ll be hard to see in the glare of morning twilight.

Jupiter will become easier to see before sunrise around mid-December, when it rises an hour or so before the sun. Around this time, Mercury reaches its greatest western (morning) elongation of 21 degrees from the rising sun. Because Mercury will rise before Jupiter does in mid-December, an imaginary line from Venus through Mercury may enable you to locate Jupiter near the horizon. See the above sky chart.

After mid-December, Jupiter will climb upward toward Mercury, as Mercury is sinking downward, toward Jupiter. Circle December 21 on your calendar, and watch for these two worlds to meet up for a close-knit conjunction. See the sky chart below.

Mercury and Jupiter are in conjunction on December 21, 2018. Very conveniently, these two worlds will easily fit within a single binocular field of view. Read more.

Jupiter rapidly climbs out of the glare of sunrise, coming up a solid two hours before the sun by the month’s end from most places worldwide. Mercury, though sinking sunward, will still rise a good hour before the sun on the last day of 2018. So, as the year draws to a close, watch for picturesque line-up of the waning crescent moon with Venus, Jupiter and Mercury about an hour before sunrise on December 31, as shown on the sky chart below.

On the last morning of the year – December 31, 2018 – watch for the moon to line up with the planets Venus, Jupiter and Mercury. Read more.

Mars and Saturn are the only two bright planets to appear the December 2018 evening sky – though Saturn, for the most part, only nominally so. Saturn sinks closer and closer to the sunset throughout December, and by mid-December will set too soon after the sun to be visible. Your best chance of spotting Saturn may be at dusk/nightfall on December 8 and 9, when the young waxing crescent moon swings rather close to Saturn on the sky’s dome. See the sky chart below.

Let the waxing crescent moon help guide your eye to the planet Saturn in December 2018. Saturn will disappear from the evening sky soon thereafter. Read more.

Fortunately, Mars remains bright and beautiful, shining more brilliantly than a 1st-magnitude star throughout December 2018. In December, Mars transits – reaches its highest point in the sky – at dusk in the Northern Hemisphere, yet before sunset in the Southern Hemisphere. Best of all, Mars stays out till around midnight in both the Northern and Southern Hemispheres.

Click here for a recommended sky almanac providing you with the transit times for Mars.

Watch for the moon to be in the vicinity of Mars for several evenings, centered on or near December 14. Fortunately, the moon will set before the peak hours of the Geminid meteor shower, centered around 2 in the morning on December 13 and 14. See the sky chart below.

On the expected peak night of the Geminids, the moon will be close to Mars on the sky’s dome. Mars’ setting at late night preludes the Geminid’s most prolific display of streaking meteors. Read more.

Saturn will swing over to the morning sky in January 2019, leaving Mars as the only bright planet to adorn the January 2019 evening sky.

Mercury, the innermost planet of the solar system, is a morning planet all month long in December 2018. Mercury might become visible before sunrise by the end of the first week of December. Look for Mercury beneath Venus, as shown on the sky chart below. By mid-December, Mercury rises about 90 minutes before the sun at mid-northern latitudes; from temperate latitudes in the Southern Hemisphere, it’s more like 75 minutes before sunrise. The crowning moment will come on the solstice, when Mercury and Jupiter have their conjunction on December 21.

Let Venus help guide your eye to Mercury .Venus rises in the predawn hours whereas Mercury follows Venus into the morning sky as nighttime gives way to morning dawn. Read more.

What do we mean by bright planet? By bright planet, we mean any solar system planet that is easily visible without an optical aid and that has been watched by our ancestors since time immemorial. In their outward order from the sun, the five bright planets are Mercury, Venus, Mars, Jupiter and Saturn. These planets actually do appear bright in our sky. They are typically as bright as – or brighter than – the brightest stars. Plus, these relatively nearby worlds tend to shine with a steadier light than the distant, twinkling stars. You can spot them, and come to know them as faithful friends, if you try.

Skywatcher, by Predrag Agatonovic.

Bottom line: In December 2018, Mars shines in the evening sky all month long. Saturn disappears in the sunset glare by about mid-month. Venus lights up the eastern sky before sunrise all month. Mercury and Jupiter join Venus in the morning sky around mid-December. Click here for recommended almanacs; they can help you know when the planets rise, transit and set in your sky.

Don’t miss anything. Subscribe to EarthSky News by email

Visit EarthSky’s Best Places to Stargaze, and recommend a place we can all enjoy. Zoom out for worldwide map.

Help EarthSky keep going! Donate now.



from EarthSky https://ift.tt/1YD00CF

When is my earliest sunset?

Adrian Strand captured this photo on a beach in northwest England.

Adrian Strand captured this photo on a beach in northwest England.

The winter solstice is the shortest day. It offers the shortest period of daylight. But, unless you live close to the Arctic Circle or Antarctic Circle, your earliest sunsets aren’t on or even near the solstice itself. Instead, your earliest sunsets will come before the winter solstice. The exact date of earliest sunset depends on your latitude. If you live in the southernmost U.S., or a comparable latitude (say, around 25 or 26 degrees N. latitude), your earliest sunsets are in late November. If you’re farther north – say, around 40 degrees N. latitude – your earliest sunsets are around December 7.

Stephen Aman shares his map of the United States that lists the dates of the year’s earliest sunset for various latitudes. Thank you Stephen!

And if you live in the Southern Hemisphere, your earliest sunrises are coming around now. Southern Hemisphere? Click here.

Why isn’t the earliest sunset on the year’s shortest day? To understand it, try thinking about it in terms of solar noon or midday, the time midway between sunrise and sunset, when the sun reaches its highest point for the day.

A clock ticks off exactly 24 hours from one noon to the next. But the actual days – as measured by the spin of the Earth – are rarely exactly 24 hours long.

So the exact time of solar noon, as measured by Earth’s spin, shifts in a seasonal way. If you measured Earth’s spin from one solar noon to the next, you’d find that – around the time of the December solstice – the time period between consecutive solar noons is actually half a minute longer than 24 hours.

So – two weeks before the solstice, for example – the sun reaches its noontime position at 11:52 a.m. local standard time. Two weeks later – on the winter solstice – the sun reaches its noontime position at 11:59 a.m. That’s 7 minutes later.

The later clock time for solar noon also means a later clock time for sunrise and sunset.

Click here for the December 2018 calendar, giving you the clock time for solar noon (check the solar noon box).

The result: earlier sunsets before the winter solstice and increasingly later sunrises for a few weeks after the winter solstice.

The exact date of earliest sunset varies with latitude. But the sequence is always the same. For the Northern Hemisphere, earliest sunset in early December, winter solstice, latest sunrise in early January.

In early December, the Southern Hemisphere is approaching its summer solstice. Sunset on that part of Earth will continue coming later until early July. Photo of sunset with crepuscular rays by Phil Rettke Photography in Ipswich QLD Australia. Visit Phil Rettke on Facebook.

In early December, the Southern Hemisphere is approaching its summer solstice. Sunset on that part of Earth will continue coming later until early January. Photo of sunset with crepuscular rays by Phil Rettke Photography in Ipswich, Queensland, Australia.

Meanwhile, if you’re in the Southern Hemisphere, take nearly everything we say here and apply it to your winter solstice in June. For the Southern Hemisphere, the earliest sunsets come prior to the winter solstice, which is typically around June 21. The latest sunrises occur after the June winter solstice.

During the month of December, it’s nearly summer in the Southern Hemisphere; the summer solstice comes this month for that hemisphere. So sunsets and sunrises are shifting in a similar way. For both hemispheres, the sequence in summer is: earliest sunrises before the summer solstice, then the summer solstice itself, then latest sunsets after the summer solstice.

As always, things get tricky if you look closely. Assuming you’re at a mid-temperate latitude, the earliest sunset for the Northern Hemisphere – and earliest sunrise for the Southern Hemisphere – come about two weeks before the December solstice, and the latest sunrise/latest sunset happen about two weeks after.

But at the other end of the year, in June and July, the time period is not equivalent. Again assuming a mid-temperate latitude, the earliest sunrise for the Northern Hemisphere – and earliest sunset for the Southern Hemisphere – comes only about one week before the June solstice, and the latest sunset/latest sunrise happens about one week after.

The time difference is due to the fact that the December solstice occurs when Earth is near its perihelion – or closest point to the sun – around which time we’re moving fastest in orbit. Meanwhile, the June solstice occurs when Earth is near aphelion – our farthest point from the sun – around which time we’re moving at our slowest in orbit.

View larger. Computed position of the sun looking eastward at the same time each morning from the Northern Hemisphere. December solstice point at lower right and June solstice point at upper left. Solar days are longer than 24 hours long at the solstices, yet less than 24 hours long at the equinoxes. Roughly midway between a solstice and an equinox, or vice versa, the solar day is exactly 24 hours long.

View larger. Computed position of the sun looking eastward at the same time each morning from the Northern Hemisphere. December solstice point at lower right and June solstice point at upper left. Solar days are longer than 24 hours long at the solstices, yet less than 24 hours long at the equinoxes. Roughly midway between a solstice and an equinox, or vice versa, the solar day is exactly 24 hours long.

In short, the earliest sunset/winter solstice/latest sunrise and earliest sunrise/summer solstice/latest sunset phenomena are due to the fact that true solar days are longer than 24 hours long for several weeks before and after the solstices. At and around the solstices, the Earth must rotate farther on its axis for the sun to return to its daily noontime position, primarily because the sun is appreciably north or south of the Earth’s equator.

However, perihelion accentuates the effect around the December solstice, giving a day length of 24 hours 30 seconds. And aphelion lessens the effect around the June solstice, giving a day length of 24 hours 13 seconds.

Bottom line: The earliest sunsets and latest sunrises don’t come on the winter solstice, the shortest day of the year. Instead, earliest sunsets come some weeks before the winter solstice. Latest sunrises come some weeks after it.

Here are more details about the earliest sunsets.



from EarthSky https://ift.tt/2G2Ot1p
Adrian Strand captured this photo on a beach in northwest England.

Adrian Strand captured this photo on a beach in northwest England.

The winter solstice is the shortest day. It offers the shortest period of daylight. But, unless you live close to the Arctic Circle or Antarctic Circle, your earliest sunsets aren’t on or even near the solstice itself. Instead, your earliest sunsets will come before the winter solstice. The exact date of earliest sunset depends on your latitude. If you live in the southernmost U.S., or a comparable latitude (say, around 25 or 26 degrees N. latitude), your earliest sunsets are in late November. If you’re farther north – say, around 40 degrees N. latitude – your earliest sunsets are around December 7.

Stephen Aman shares his map of the United States that lists the dates of the year’s earliest sunset for various latitudes. Thank you Stephen!

And if you live in the Southern Hemisphere, your earliest sunrises are coming around now. Southern Hemisphere? Click here.

Why isn’t the earliest sunset on the year’s shortest day? To understand it, try thinking about it in terms of solar noon or midday, the time midway between sunrise and sunset, when the sun reaches its highest point for the day.

A clock ticks off exactly 24 hours from one noon to the next. But the actual days – as measured by the spin of the Earth – are rarely exactly 24 hours long.

So the exact time of solar noon, as measured by Earth’s spin, shifts in a seasonal way. If you measured Earth’s spin from one solar noon to the next, you’d find that – around the time of the December solstice – the time period between consecutive solar noons is actually half a minute longer than 24 hours.

So – two weeks before the solstice, for example – the sun reaches its noontime position at 11:52 a.m. local standard time. Two weeks later – on the winter solstice – the sun reaches its noontime position at 11:59 a.m. That’s 7 minutes later.

The later clock time for solar noon also means a later clock time for sunrise and sunset.

Click here for the December 2018 calendar, giving you the clock time for solar noon (check the solar noon box).

The result: earlier sunsets before the winter solstice and increasingly later sunrises for a few weeks after the winter solstice.

The exact date of earliest sunset varies with latitude. But the sequence is always the same. For the Northern Hemisphere, earliest sunset in early December, winter solstice, latest sunrise in early January.

In early December, the Southern Hemisphere is approaching its summer solstice. Sunset on that part of Earth will continue coming later until early July. Photo of sunset with crepuscular rays by Phil Rettke Photography in Ipswich QLD Australia. Visit Phil Rettke on Facebook.

In early December, the Southern Hemisphere is approaching its summer solstice. Sunset on that part of Earth will continue coming later until early January. Photo of sunset with crepuscular rays by Phil Rettke Photography in Ipswich, Queensland, Australia.

Meanwhile, if you’re in the Southern Hemisphere, take nearly everything we say here and apply it to your winter solstice in June. For the Southern Hemisphere, the earliest sunsets come prior to the winter solstice, which is typically around June 21. The latest sunrises occur after the June winter solstice.

During the month of December, it’s nearly summer in the Southern Hemisphere; the summer solstice comes this month for that hemisphere. So sunsets and sunrises are shifting in a similar way. For both hemispheres, the sequence in summer is: earliest sunrises before the summer solstice, then the summer solstice itself, then latest sunsets after the summer solstice.

As always, things get tricky if you look closely. Assuming you’re at a mid-temperate latitude, the earliest sunset for the Northern Hemisphere – and earliest sunrise for the Southern Hemisphere – come about two weeks before the December solstice, and the latest sunrise/latest sunset happen about two weeks after.

But at the other end of the year, in June and July, the time period is not equivalent. Again assuming a mid-temperate latitude, the earliest sunrise for the Northern Hemisphere – and earliest sunset for the Southern Hemisphere – comes only about one week before the June solstice, and the latest sunset/latest sunrise happens about one week after.

The time difference is due to the fact that the December solstice occurs when Earth is near its perihelion – or closest point to the sun – around which time we’re moving fastest in orbit. Meanwhile, the June solstice occurs when Earth is near aphelion – our farthest point from the sun – around which time we’re moving at our slowest in orbit.

View larger. Computed position of the sun looking eastward at the same time each morning from the Northern Hemisphere. December solstice point at lower right and June solstice point at upper left. Solar days are longer than 24 hours long at the solstices, yet less than 24 hours long at the equinoxes. Roughly midway between a solstice and an equinox, or vice versa, the solar day is exactly 24 hours long.

View larger. Computed position of the sun looking eastward at the same time each morning from the Northern Hemisphere. December solstice point at lower right and June solstice point at upper left. Solar days are longer than 24 hours long at the solstices, yet less than 24 hours long at the equinoxes. Roughly midway between a solstice and an equinox, or vice versa, the solar day is exactly 24 hours long.

In short, the earliest sunset/winter solstice/latest sunrise and earliest sunrise/summer solstice/latest sunset phenomena are due to the fact that true solar days are longer than 24 hours long for several weeks before and after the solstices. At and around the solstices, the Earth must rotate farther on its axis for the sun to return to its daily noontime position, primarily because the sun is appreciably north or south of the Earth’s equator.

However, perihelion accentuates the effect around the December solstice, giving a day length of 24 hours 30 seconds. And aphelion lessens the effect around the June solstice, giving a day length of 24 hours 13 seconds.

Bottom line: The earliest sunsets and latest sunrises don’t come on the winter solstice, the shortest day of the year. Instead, earliest sunsets come some weeks before the winter solstice. Latest sunrises come some weeks after it.

Here are more details about the earliest sunsets.



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Take 2 trips around Earth, from space

The European Space Agency (ESA) released this timelapse video this month (November 19, 2018) in celebration of the launch 20 years ago of the International Space Station (ISS). ESA astronaut Alexander Gerst acquired the images for the timelapse in October 2018. At just under 15 minutes, it’s the longest-yet continuous timelapse from space.

The video takes you from Tunisia across Beijing and through Australia in two trips around the world. You can follow the Station’s location on the map at the top right of the screen beside annotations on the photos themselves. Because the map is a two-dimensional representation of Earth’s globe, the ground track of the ISS appears to be wavy.

This timelapse comprises more than 21,000 images of Earth captured by Gerst from the ISS orbiting at its 250-mile (400-km) altitude about our world’s surface. The video is shown 12.5 times faster than actual speed.

At 18,000 miles (28,800 km) per hour, it only takes 90 minutes for the ISS to make a complete circuit of Earth, so the video shows the world passing from day to night and back again twice. The darker regions on the map shows where night is on Earth.

You can see numerous flashes of lightning during night time. That’s lightning from storms and is common on our planet. Also at night, look for stars rising above the horizon through the faint glow of the atmosphere still illuminated by the sun.

Here’s more from ESA:

As the Space Station flies into the night the solar wings rotate to get ready to capture the next rays of sunlight when the orbital outpost moves outside of the shadow of Earth. On the right is Japan’s cargo spacecraft HTV-7 that was docked with the International Space Station until November 7, 2018.

The white panels visible top left from 05:30 are the International Space Station’s radiators that pump ammonia to exchange heat and keep the facilities and astronauts inside at the right temperature.

At 06:55 the International Space Station flies over Europe starting with Portugal and Spain. Each new orbit of Earth sees the Space Station fly slightly more to the west than the orbit before.

Bottom line: The longest-yet timelapse from space, from ISS astronaut Alexander Gerst. Take two trips around the Earth in just under 15 minutes.

Via ESA

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The European Space Agency (ESA) released this timelapse video this month (November 19, 2018) in celebration of the launch 20 years ago of the International Space Station (ISS). ESA astronaut Alexander Gerst acquired the images for the timelapse in October 2018. At just under 15 minutes, it’s the longest-yet continuous timelapse from space.

The video takes you from Tunisia across Beijing and through Australia in two trips around the world. You can follow the Station’s location on the map at the top right of the screen beside annotations on the photos themselves. Because the map is a two-dimensional representation of Earth’s globe, the ground track of the ISS appears to be wavy.

This timelapse comprises more than 21,000 images of Earth captured by Gerst from the ISS orbiting at its 250-mile (400-km) altitude about our world’s surface. The video is shown 12.5 times faster than actual speed.

At 18,000 miles (28,800 km) per hour, it only takes 90 minutes for the ISS to make a complete circuit of Earth, so the video shows the world passing from day to night and back again twice. The darker regions on the map shows where night is on Earth.

You can see numerous flashes of lightning during night time. That’s lightning from storms and is common on our planet. Also at night, look for stars rising above the horizon through the faint glow of the atmosphere still illuminated by the sun.

Here’s more from ESA:

As the Space Station flies into the night the solar wings rotate to get ready to capture the next rays of sunlight when the orbital outpost moves outside of the shadow of Earth. On the right is Japan’s cargo spacecraft HTV-7 that was docked with the International Space Station until November 7, 2018.

The white panels visible top left from 05:30 are the International Space Station’s radiators that pump ammonia to exchange heat and keep the facilities and astronauts inside at the right temperature.

At 06:55 the International Space Station flies over Europe starting with Portugal and Spain. Each new orbit of Earth sees the Space Station fly slightly more to the west than the orbit before.

Bottom line: The longest-yet timelapse from space, from ISS astronaut Alexander Gerst. Take two trips around the Earth in just under 15 minutes.

Via ESA

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ExoMars will land in Oxia Planum in 2021

Map of Mars showing the 2 finalist landing sites on Mars, Mawrth Vallis and Oxia Planum. Now Oxia Planum has been given the nod for ESA’s ExoMars mission. Image via NASA/JPL/USGS.

Mars will continue to be a busy place in the near future, with NASA’s InSight spacecraft landing just a few days ago on November 26, and the Mars 2020 rover landing in 2021. But NASA is not the only one going back to the red planet – the European Space Agency (ESA) is getting ready for its own rover mission – ExoMars – which will also land in 2021. The landing site for ExoMars was announced this month (November 2018), and the winner is Oxia Planum.

The ExoMars rover mission is designed specifically to look for evidence of life on Mars, most likely underground if it exists. According to Graham Turnock, Chief Executive at the UK Space Agency:

After the Earth, Mars is the most habitable planet in the solar system, so it’s a perfect destination to explore the possibility of life on other planets, as well as the history of our own.

The UK Space Agency is the second-largest European contributor to the ExoMars mission, with €287 million invested in the overall mission and £14 million in the instruments. UKSA also negotiated key mission contracts with ESA.

EarthSky lunar calendars are cool! They make great gifts. Order now. Going fast!

Artist’s concept of the ExoMars rover, which will land in Oxia Planum in 2021. Image via ESA.

Oxia Planum was finally chosen over Mawrth Vallis, the other of the two finalist candidate landing sites, both of which used to be water-rich in the distant past. John Bridges, from the Space Research Centre, University of Leicester, and a member of the Landing Site Selection Working Group, explained how Oxia Planum was chosen over other candidate landing sites:

After over 4 years of careful study of HiRISE and more recently CaSSIS images Oxia Planum was chosen because scientists were convinced that its fine grained sediments, deposited during the ancient Noachian epoch were ideally suited for the Exobiology rover.

With an enormous catchment area the sediments will have captured organics from a wide variety of environments over a long period of time, including areas where life may have existed. The fine sediments should also be ideal for the ExoMars drill – it aims to get to 2 metres depth.

Remote identification with the Mars Express and Mars Reconnaissance Orbiter infrared spectrometers shows the presence of clays and other minerals giving clues to its aqueous history.

A large group of scientists have been working on proposing, characterising and down selecting the sites, all of which had fascinating aspects, but Oxia Planum is the clear winner on both science and engineering constraints.

A texture map of Oxia Planum, created from data taken by NASA’s Mars Odyssey orbiter. Image via IRSPS/TAS/NASA/JPL-Caltech/Arizona State University.

As Sue Horne, Head of Space Exploration at the UK Space Agency also noted:

I have been working on ExoMars for over ten years and am amazed at the ingenuity and dedication of UK engineers and scientists in building the rover and instruments that will work in the extreme environment of Mars.

Our end goal is in sight and it is getting very exciting.

ExoMars will be the second Mars mission, after only Mars 2020 and the Viking landers in the late 1970s/early 1980s to search directly for evidence of life instead of only focusing past habitability. According to ExoMars 2020 project scientist Jorge Vago:

With ExoMars we are on a quest to find biosignatures. While both sites offer valuable scientific opportunities to explore ancient water-rich environments that could have been colonised by microorganisms, Oxia Planum received the majority of votes.

An impressive amount of work has gone into characterising the proposed sites, demonstrating that they meet the scientific requirements for the goals of the ExoMars mission. Mawrth Vallis is a scientifically unique site, but Oxia Planum offers an additional safety margin for entry, descent and landing, and for traversing the terrain to reach the scientifically interesting sites that have been identified from orbit.

A portion of Oxia Planum, as seen by NASA’s Mars Reconnaissance Orbiter. Image via NASA/JPL-Caltech/MSSS.

Oxia Planum is just north of the martian equator, in a region with many channels – carved by ancient rivers – cutting through from the southern highlands to the northern lowlands. Such previously water-rich areas are prime targets for rovers and landers when searching for evidence of not only past habitability, but even life itself. Oxia Planum is at a boundary where many channels emptied into the lower plains, and those plains exhibit layers of clay-rich minerals that were formed in water-rich conditions about four billion years ago. The channels cover a large area, about 131,000 square miles (212,000 square km).

The rover will drill down into the martian surface – up to 6.5 feet (two meters) deep – to look for organic material that could be evidence for life. It is designed to take a minimum of 17 samples to be analyzed by the Analytical Laboratory Drawer.

Comparison of different components of the ExoMars mission to the Big Ben tower in London. Image via ESA.

Landing on Mars is never easy, but Francois Spoto, ExoMars Programme team leader, is confident:

Our ExoMars mission combines extreme performance with the novel design features of the rover, and we are looking forward to operating the first European mission on the surface of Mars. Landing on Mars has a long chain of risks, but thanks to the combined skills and expertise of European and Russian industries working with reliable technologies, we are focused on a safe landing.

The other part of the ExoMars mission, the Trace Gas Orbiter, has already been orbiting Mars for several months now, and is analyzing the atmosphere, including looking for trace gases such as methane – detected previously by other telescopes, orbiters and the Curiosity rover – that could indicate possible current life or geologic activity.

Bottom line: The next phase of the ExoMars mission – the 2021 rover – will be an exciting one, as it explores Oxia Planum searching for signs of life beneath the once wet but now dry and sandy surface.

Via ESA



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Map of Mars showing the 2 finalist landing sites on Mars, Mawrth Vallis and Oxia Planum. Now Oxia Planum has been given the nod for ESA’s ExoMars mission. Image via NASA/JPL/USGS.

Mars will continue to be a busy place in the near future, with NASA’s InSight spacecraft landing just a few days ago on November 26, and the Mars 2020 rover landing in 2021. But NASA is not the only one going back to the red planet – the European Space Agency (ESA) is getting ready for its own rover mission – ExoMars – which will also land in 2021. The landing site for ExoMars was announced this month (November 2018), and the winner is Oxia Planum.

The ExoMars rover mission is designed specifically to look for evidence of life on Mars, most likely underground if it exists. According to Graham Turnock, Chief Executive at the UK Space Agency:

After the Earth, Mars is the most habitable planet in the solar system, so it’s a perfect destination to explore the possibility of life on other planets, as well as the history of our own.

The UK Space Agency is the second-largest European contributor to the ExoMars mission, with €287 million invested in the overall mission and £14 million in the instruments. UKSA also negotiated key mission contracts with ESA.

EarthSky lunar calendars are cool! They make great gifts. Order now. Going fast!

Artist’s concept of the ExoMars rover, which will land in Oxia Planum in 2021. Image via ESA.

Oxia Planum was finally chosen over Mawrth Vallis, the other of the two finalist candidate landing sites, both of which used to be water-rich in the distant past. John Bridges, from the Space Research Centre, University of Leicester, and a member of the Landing Site Selection Working Group, explained how Oxia Planum was chosen over other candidate landing sites:

After over 4 years of careful study of HiRISE and more recently CaSSIS images Oxia Planum was chosen because scientists were convinced that its fine grained sediments, deposited during the ancient Noachian epoch were ideally suited for the Exobiology rover.

With an enormous catchment area the sediments will have captured organics from a wide variety of environments over a long period of time, including areas where life may have existed. The fine sediments should also be ideal for the ExoMars drill – it aims to get to 2 metres depth.

Remote identification with the Mars Express and Mars Reconnaissance Orbiter infrared spectrometers shows the presence of clays and other minerals giving clues to its aqueous history.

A large group of scientists have been working on proposing, characterising and down selecting the sites, all of which had fascinating aspects, but Oxia Planum is the clear winner on both science and engineering constraints.

A texture map of Oxia Planum, created from data taken by NASA’s Mars Odyssey orbiter. Image via IRSPS/TAS/NASA/JPL-Caltech/Arizona State University.

As Sue Horne, Head of Space Exploration at the UK Space Agency also noted:

I have been working on ExoMars for over ten years and am amazed at the ingenuity and dedication of UK engineers and scientists in building the rover and instruments that will work in the extreme environment of Mars.

Our end goal is in sight and it is getting very exciting.

ExoMars will be the second Mars mission, after only Mars 2020 and the Viking landers in the late 1970s/early 1980s to search directly for evidence of life instead of only focusing past habitability. According to ExoMars 2020 project scientist Jorge Vago:

With ExoMars we are on a quest to find biosignatures. While both sites offer valuable scientific opportunities to explore ancient water-rich environments that could have been colonised by microorganisms, Oxia Planum received the majority of votes.

An impressive amount of work has gone into characterising the proposed sites, demonstrating that they meet the scientific requirements for the goals of the ExoMars mission. Mawrth Vallis is a scientifically unique site, but Oxia Planum offers an additional safety margin for entry, descent and landing, and for traversing the terrain to reach the scientifically interesting sites that have been identified from orbit.

A portion of Oxia Planum, as seen by NASA’s Mars Reconnaissance Orbiter. Image via NASA/JPL-Caltech/MSSS.

Oxia Planum is just north of the martian equator, in a region with many channels – carved by ancient rivers – cutting through from the southern highlands to the northern lowlands. Such previously water-rich areas are prime targets for rovers and landers when searching for evidence of not only past habitability, but even life itself. Oxia Planum is at a boundary where many channels emptied into the lower plains, and those plains exhibit layers of clay-rich minerals that were formed in water-rich conditions about four billion years ago. The channels cover a large area, about 131,000 square miles (212,000 square km).

The rover will drill down into the martian surface – up to 6.5 feet (two meters) deep – to look for organic material that could be evidence for life. It is designed to take a minimum of 17 samples to be analyzed by the Analytical Laboratory Drawer.

Comparison of different components of the ExoMars mission to the Big Ben tower in London. Image via ESA.

Landing on Mars is never easy, but Francois Spoto, ExoMars Programme team leader, is confident:

Our ExoMars mission combines extreme performance with the novel design features of the rover, and we are looking forward to operating the first European mission on the surface of Mars. Landing on Mars has a long chain of risks, but thanks to the combined skills and expertise of European and Russian industries working with reliable technologies, we are focused on a safe landing.

The other part of the ExoMars mission, the Trace Gas Orbiter, has already been orbiting Mars for several months now, and is analyzing the atmosphere, including looking for trace gases such as methane – detected previously by other telescopes, orbiters and the Curiosity rover – that could indicate possible current life or geologic activity.

Bottom line: The next phase of the ExoMars mission – the 2021 rover – will be an exciting one, as it explores Oxia Planum searching for signs of life beneath the once wet but now dry and sandy surface.

Via ESA



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The future disappearance of Quelccaya Ice Cap

Image via GlacierHub.

This article is republished with permission from GlacierHub. This post was written by Nabilah Islam.

Quelccaya is the largest tropical ice cap in the world. It is located in the Central Andes of Peru and has a summit elevation of about 5,680 meters [18,635 feet]. A recent study suggests that the ice cap might soon cease to exist. Researchers used climate data to examine the impacts of the different forcings [or causes of change] to determine how imminent its future disappearance is, and to what extent human activity affects the timing.

About 99 percent of the world’s tropical glaciers are located in the Andes, with around 70 percent found in Peru. Glaciers in the tropical Andes are critical to the regional environment. Through runoff, they provide a much-needed water supply during the dry season. A future disappearance of Quelccaya Ice Cap (QIC) could mean significant changes to the ecosystem, impacts on tourism, and consequences to the culture and traditions of the local populations.

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Andes mountains in Peru. Image via Michael Mcdonough/Flickr.

Scientists used daily air temperature and snow height data to build projections of retreat at the QIC. Air temperature over the Peruvian Andes has increased over the last six decades, leading to greater retreat. Rising air surface temperatures are one of the major contributors to this retreat, although variations in precipitation and snowfall contribute as well. Meanwhile, El Nino and the South American Summer Monsoon can also impact QIC conditions, but on an interannual timescale.

The researchers also examined the different Representative Concentration Pathway scenarios (RCPs) that play a huge role in the future of tropical glaciers. RCPs are used in scientific modeling to provide temporal projections on greenhouse gas concentrations. These concentrations contribute to warming and have a great effect on glaciers. The rate of warming is typically amplified with elevation in many mountain regions due to elevation dependent feedbacks, which are explained further in the study.

Results of the research show that through anthropogenic and natural forcings, QIC loses mass at its front and base. This means that by around 2050, the ice cap could completely disappear. Even with a great reduction in greenhouse gas concentrations, results indicate that an eventual disappearance can be expected closer to the end of the century. The researchers further explained that these findings are consistent with observations of other glaciers in the tropics. We can look at glaciers in Bolivia, Colombia, and Venezuela, as they have also experienced accelerated retreat over the last decades.

Andrew Malone, a Visiting Assistant Professor at The University of Illinois at Chicago (UIC), told GlacierHub more about the shrinking of QIC and its impacts. “The largest impact would be on loss of water resources for communities both locally and downstream. In the short-term accelerated melting actually increases water resources. But as ice melts, that ‘stored’ water shrinks and shrinks, and at some point the glacier reservoir becomes so small that the total run-off contribution starts to decrease with time,” he said.

The melting of Qori Kalis glacier. The left is the glacier in 1978. Right image is from 2011, presenting a retreated glacier and the lake left from melt. Image via Bird Lai/Flickr.

Malone went on to explain that as glaciers melt, lakes form in their place. These lakes are dammed by glacial moraines, which are formed by buildup of falling dirt and rocks from melting glaciers. Moraines are not structurally sound. As ice falls off glaciers and into the new lakes, large waves can form and flood the downstream landscape. Malone said that this has happened to the lake in Qori Kalis valley, and as a result livestock were lost with the flooding. Similar events can be expected to happen at QIC as well.

While there is much research and understanding of the glacial and environmental impacts of climate change, the human impacts should also be considered. GlacierHub spoke with anthropologist Gustavo Valdivia, who is currently doing research on the Andes. His research looks at the impacts of QIC glacier melt on the nearby community of Phinaya. This community relies on herding alpaca, selling alpaca wool for their livelihood; thus, they are very dependent on runoff waters to irrigate the pastures for their flocks. At present the Phinaya community benefits from the greater runoff, Valdivia said, but this abundance is not likely to last long. The livestock might also be at risk from flooding, as seen in Qori Kalis.

EarthSky lunar calendars are cool! They make great gifts. Order now. Going fast!

Alpaca from the Phinaya community of Peru. Image via Christian Aid/Flickr.

Valdivia added that there is a key difference between understanding and experiencing climate. Researchers understand the science behind glacial retreat and warming, but it’s the people who experience these changes. He highlighted the importance of building genuine communication with scientific information. As glaciers continue to melt, it’s vital to build connections to the people and communities who are affected, examining ways in which we can adapt to the changes in our climate and environment. Though each community faces climate change in a specific way, they are also part of a global process of change.

Bottom line: A recent study suggests that the Quelccaya ice cap in Peru might soon cease to exist.

Via GlacierHub



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Image via GlacierHub.

This article is republished with permission from GlacierHub. This post was written by Nabilah Islam.

Quelccaya is the largest tropical ice cap in the world. It is located in the Central Andes of Peru and has a summit elevation of about 5,680 meters [18,635 feet]. A recent study suggests that the ice cap might soon cease to exist. Researchers used climate data to examine the impacts of the different forcings [or causes of change] to determine how imminent its future disappearance is, and to what extent human activity affects the timing.

About 99 percent of the world’s tropical glaciers are located in the Andes, with around 70 percent found in Peru. Glaciers in the tropical Andes are critical to the regional environment. Through runoff, they provide a much-needed water supply during the dry season. A future disappearance of Quelccaya Ice Cap (QIC) could mean significant changes to the ecosystem, impacts on tourism, and consequences to the culture and traditions of the local populations.

EarthSky lunar calendars are cool! They make great gifts. Order now. Going fast!

Andes mountains in Peru. Image via Michael Mcdonough/Flickr.

Scientists used daily air temperature and snow height data to build projections of retreat at the QIC. Air temperature over the Peruvian Andes has increased over the last six decades, leading to greater retreat. Rising air surface temperatures are one of the major contributors to this retreat, although variations in precipitation and snowfall contribute as well. Meanwhile, El Nino and the South American Summer Monsoon can also impact QIC conditions, but on an interannual timescale.

The researchers also examined the different Representative Concentration Pathway scenarios (RCPs) that play a huge role in the future of tropical glaciers. RCPs are used in scientific modeling to provide temporal projections on greenhouse gas concentrations. These concentrations contribute to warming and have a great effect on glaciers. The rate of warming is typically amplified with elevation in many mountain regions due to elevation dependent feedbacks, which are explained further in the study.

Results of the research show that through anthropogenic and natural forcings, QIC loses mass at its front and base. This means that by around 2050, the ice cap could completely disappear. Even with a great reduction in greenhouse gas concentrations, results indicate that an eventual disappearance can be expected closer to the end of the century. The researchers further explained that these findings are consistent with observations of other glaciers in the tropics. We can look at glaciers in Bolivia, Colombia, and Venezuela, as they have also experienced accelerated retreat over the last decades.

Andrew Malone, a Visiting Assistant Professor at The University of Illinois at Chicago (UIC), told GlacierHub more about the shrinking of QIC and its impacts. “The largest impact would be on loss of water resources for communities both locally and downstream. In the short-term accelerated melting actually increases water resources. But as ice melts, that ‘stored’ water shrinks and shrinks, and at some point the glacier reservoir becomes so small that the total run-off contribution starts to decrease with time,” he said.

The melting of Qori Kalis glacier. The left is the glacier in 1978. Right image is from 2011, presenting a retreated glacier and the lake left from melt. Image via Bird Lai/Flickr.

Malone went on to explain that as glaciers melt, lakes form in their place. These lakes are dammed by glacial moraines, which are formed by buildup of falling dirt and rocks from melting glaciers. Moraines are not structurally sound. As ice falls off glaciers and into the new lakes, large waves can form and flood the downstream landscape. Malone said that this has happened to the lake in Qori Kalis valley, and as a result livestock were lost with the flooding. Similar events can be expected to happen at QIC as well.

While there is much research and understanding of the glacial and environmental impacts of climate change, the human impacts should also be considered. GlacierHub spoke with anthropologist Gustavo Valdivia, who is currently doing research on the Andes. His research looks at the impacts of QIC glacier melt on the nearby community of Phinaya. This community relies on herding alpaca, selling alpaca wool for their livelihood; thus, they are very dependent on runoff waters to irrigate the pastures for their flocks. At present the Phinaya community benefits from the greater runoff, Valdivia said, but this abundance is not likely to last long. The livestock might also be at risk from flooding, as seen in Qori Kalis.

EarthSky lunar calendars are cool! They make great gifts. Order now. Going fast!

Alpaca from the Phinaya community of Peru. Image via Christian Aid/Flickr.

Valdivia added that there is a key difference between understanding and experiencing climate. Researchers understand the science behind glacial retreat and warming, but it’s the people who experience these changes. He highlighted the importance of building genuine communication with scientific information. As glaciers continue to melt, it’s vital to build connections to the people and communities who are affected, examining ways in which we can adapt to the changes in our climate and environment. Though each community faces climate change in a specific way, they are also part of a global process of change.

Bottom line: A recent study suggests that the Quelccaya ice cap in Peru might soon cease to exist.

Via GlacierHub



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Pink lunar halo

Image via Eliot Herman.

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