Earliest flying mammals discovered

Maiopatagium in Jurassic forest in crepuscular (dawn and dusk) light: A mother with a baby in suspending roosting posture, climbing on tree trunk, and in gliding. Image via April I. Neander/UChicago.

Scientists say that two 160 million-year-old mammal fossils discovered in China, from the dinosaur-dominated Jurassic Period are the are the oldest known gliders in the long history of early mammals. With long limbs, long hand and foot fingers, and wing-like membranes, these early mammals – Maiopatagium furculiferum and Vilevolodon diplomylos – evolved to glide and live in trees.

The new discoveries suggest that the volant – or flying – way of life evolved among mammalian ancestors 100 million years earlier than the first modern mammal fliers. That’s according to two papers international team of scientists from the University of Chicago and Beijing Museum of Natural History published in the journal Nature in August 2017 (here and here.)

Zhe-Xi Luo, PhD is a professor of organismal biology and anatomy at the University of Chicago and an author on both papers. Luo said in a statement:

These Jurassic mammals are truly ‘the first in glide.’ In a way, they got the first wings among all mammals.

With every new mammal fossil from the Age of Dinosaurs, we continue to be surprised by how diverse mammalian forerunners were in both feeding and locomotor adaptations. The groundwork for mammals’ successful diversification today appears to have been laid long ago.


The Jurassic Maiopatagium and Vilevolodon are from an entirely extinct branch on the mammalian evolutionary tree, but are considered to be among forerunners to modern mammals. From a University of Chicago statement about the studies:

The ability to glide in the air is one of the many remarkable adaptations in mammals. Most mammals live on land, but volant mammals, including flying squirrels and bats that flap bird-like wings, made an important transition between land and aerial habitats. The ability to glide between trees allowed the ancient animals to find food that was inaccessible to other land animals. That evolutionary advantage can still be seen among today’s mammals such as flying squirrels in North America and Asia, scaly-tailed gliders of Africa, marsupial sugar gliders of Australia and colugos of Southeast Asia.

A gliding mammaliaform feeding on the soft parts of a bennethelian plant of the Jurassic. Image via April I. Neander/UChicago.

Both of the fossils show the exquisitely fossilized, wing-like skin membranes between their front and back limbs. They also show many skeletal features in their shoulder joints and forelimbs that gave the ancient animals the agility to be capable gliders. Evolutionarily, the two fossils, discovered in the Tiaojishan Formation, northeast of Beijing, China, represent the earliest examples of gliding behavior among extinct mammal ancestors.

There are some differences between the two newly-discovered extinct mammals and modern gliders, the researchers noted. Today, the hallmark of most mammal gliders is their herbivorous diet that typically consists of seeds, fruits and other soft parts of flowering plants. But Maiopatagium and Vilevolodon lived in a Jurassic world where the plant life was dominated by ferns and gymnosperm plants like cycads, gingkoes and conifers – long before flowering plants came to dominate in the Cretaceous Period, and their way of life was also associated with feeding on these entirely different plants. This distinct diet and lifestyle evolved again some 100 million years later among modern mammals.

Bottom line: Two 160 million-year-old fossils discovered in China are the oldest known mammal gliders.

Read more from the University of Chicago



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Maiopatagium in Jurassic forest in crepuscular (dawn and dusk) light: A mother with a baby in suspending roosting posture, climbing on tree trunk, and in gliding. Image via April I. Neander/UChicago.

Scientists say that two 160 million-year-old mammal fossils discovered in China, from the dinosaur-dominated Jurassic Period are the are the oldest known gliders in the long history of early mammals. With long limbs, long hand and foot fingers, and wing-like membranes, these early mammals – Maiopatagium furculiferum and Vilevolodon diplomylos – evolved to glide and live in trees.

The new discoveries suggest that the volant – or flying – way of life evolved among mammalian ancestors 100 million years earlier than the first modern mammal fliers. That’s according to two papers international team of scientists from the University of Chicago and Beijing Museum of Natural History published in the journal Nature in August 2017 (here and here.)

Zhe-Xi Luo, PhD is a professor of organismal biology and anatomy at the University of Chicago and an author on both papers. Luo said in a statement:

These Jurassic mammals are truly ‘the first in glide.’ In a way, they got the first wings among all mammals.

With every new mammal fossil from the Age of Dinosaurs, we continue to be surprised by how diverse mammalian forerunners were in both feeding and locomotor adaptations. The groundwork for mammals’ successful diversification today appears to have been laid long ago.


The Jurassic Maiopatagium and Vilevolodon are from an entirely extinct branch on the mammalian evolutionary tree, but are considered to be among forerunners to modern mammals. From a University of Chicago statement about the studies:

The ability to glide in the air is one of the many remarkable adaptations in mammals. Most mammals live on land, but volant mammals, including flying squirrels and bats that flap bird-like wings, made an important transition between land and aerial habitats. The ability to glide between trees allowed the ancient animals to find food that was inaccessible to other land animals. That evolutionary advantage can still be seen among today’s mammals such as flying squirrels in North America and Asia, scaly-tailed gliders of Africa, marsupial sugar gliders of Australia and colugos of Southeast Asia.

A gliding mammaliaform feeding on the soft parts of a bennethelian plant of the Jurassic. Image via April I. Neander/UChicago.

Both of the fossils show the exquisitely fossilized, wing-like skin membranes between their front and back limbs. They also show many skeletal features in their shoulder joints and forelimbs that gave the ancient animals the agility to be capable gliders. Evolutionarily, the two fossils, discovered in the Tiaojishan Formation, northeast of Beijing, China, represent the earliest examples of gliding behavior among extinct mammal ancestors.

There are some differences between the two newly-discovered extinct mammals and modern gliders, the researchers noted. Today, the hallmark of most mammal gliders is their herbivorous diet that typically consists of seeds, fruits and other soft parts of flowering plants. But Maiopatagium and Vilevolodon lived in a Jurassic world where the plant life was dominated by ferns and gymnosperm plants like cycads, gingkoes and conifers – long before flowering plants came to dominate in the Cretaceous Period, and their way of life was also associated with feeding on these entirely different plants. This distinct diet and lifestyle evolved again some 100 million years later among modern mammals.

Bottom line: Two 160 million-year-old fossils discovered in China are the oldest known mammal gliders.

Read more from the University of Chicago



from EarthSky http://ift.tt/2wRZHjF

Closest far-moon of 2017 on August 30

Tonight – August 30, 2017 – the moon is quite close to the planet Saturn on the sky’s dome, and it’s also at or near apogee – the moon’s farthest point from Earth for the month. The apogee on August 30, 2017, has the distinction of being the closest apogee of 2017, making tonight’s moon the closest far-moon of 2017.

Wait … what? Closest far-moon. Yes, on August 30, 2017, at 11:25 UTC, the moon reaches apogee – its most distant point from Earth for the month. But this apogee is the closest of the 13 lunar apogees that occur in 2017.

At this month’s closest apogee, the moon lies 404,308 km distant. Contrast this with the farthest apogee of the year on December 19, 2017, when the moon will lie 406,603 km away. The mean apogee distance is 405,504 km.

The moon is also near first quarter phase now. First quarter moon happened the day before this month’s lunar apogee, on August 29. It’s no coincidence that the first quarter moon – and closest far-moon – happen in close vicinity of one another.

In any year, it’s either the first quarter moon or last quarter moon that closely coincides with the year’s closest apogee. Next year, in 2018, the closest apogee of the year (404,144 km) will happen when the last quarter moon and lunar apogee fall within a few hours of each other on April 8, 2018.

Often – but not always – the year’s closest apogee will recur in a period of 14 lunar months (14 successive returns to the same phase). That’s because 14 lunar months is nearly commensurate to 15 returns to apogee.

14 lunar months x 29.53059 days = 413.428 days
15 returns to apogee x 27.55455 days = 413.318 days

This 413-day period is approximately equal to one year, month month and 18 days. And, guess what? Fourteen lunar months lunar after 2019’s closest apogee on April 8, 2018 (404,144 km), the following year’s closest apogee will fall on May 26, 2019 (404,138 km). Then 14 lunar months after the year’s closest apogee on May 26, 2019 (404,138 km), it’ll be the year’s closest apogee on July 12, 2020 (404,199 km).

Today – August 30, 2017 – the lunar apogee distance of 404,308 km presents the closest apogee of the year.

Lunar perigee and apogee calculator

Moon at perigee and apogee: 2001 to 2100

Phases of the moon: 2001 to 2100

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

Bottom line: The closest far-moon of 2017 happens on August 30. The year’s closest far-moon often takes place in the month that the quarter moon and apogee most closely align.

Moon facts at your fingertips

EarthSky astronomy kits are perfect for beginners. Order today from the EarthSky store

Donate: Your support means the world to us



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Tonight – August 30, 2017 – the moon is quite close to the planet Saturn on the sky’s dome, and it’s also at or near apogee – the moon’s farthest point from Earth for the month. The apogee on August 30, 2017, has the distinction of being the closest apogee of 2017, making tonight’s moon the closest far-moon of 2017.

Wait … what? Closest far-moon. Yes, on August 30, 2017, at 11:25 UTC, the moon reaches apogee – its most distant point from Earth for the month. But this apogee is the closest of the 13 lunar apogees that occur in 2017.

At this month’s closest apogee, the moon lies 404,308 km distant. Contrast this with the farthest apogee of the year on December 19, 2017, when the moon will lie 406,603 km away. The mean apogee distance is 405,504 km.

The moon is also near first quarter phase now. First quarter moon happened the day before this month’s lunar apogee, on August 29. It’s no coincidence that the first quarter moon – and closest far-moon – happen in close vicinity of one another.

In any year, it’s either the first quarter moon or last quarter moon that closely coincides with the year’s closest apogee. Next year, in 2018, the closest apogee of the year (404,144 km) will happen when the last quarter moon and lunar apogee fall within a few hours of each other on April 8, 2018.

Often – but not always – the year’s closest apogee will recur in a period of 14 lunar months (14 successive returns to the same phase). That’s because 14 lunar months is nearly commensurate to 15 returns to apogee.

14 lunar months x 29.53059 days = 413.428 days
15 returns to apogee x 27.55455 days = 413.318 days

This 413-day period is approximately equal to one year, month month and 18 days. And, guess what? Fourteen lunar months lunar after 2019’s closest apogee on April 8, 2018 (404,144 km), the following year’s closest apogee will fall on May 26, 2019 (404,138 km). Then 14 lunar months after the year’s closest apogee on May 26, 2019 (404,138 km), it’ll be the year’s closest apogee on July 12, 2020 (404,199 km).

Today – August 30, 2017 – the lunar apogee distance of 404,308 km presents the closest apogee of the year.

Lunar perigee and apogee calculator

Moon at perigee and apogee: 2001 to 2100

Phases of the moon: 2001 to 2100

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

Bottom line: The closest far-moon of 2017 happens on August 30. The year’s closest far-moon often takes place in the month that the quarter moon and apogee most closely align.

Moon facts at your fingertips

EarthSky astronomy kits are perfect for beginners. Order today from the EarthSky store

Donate: Your support means the world to us



from EarthSky http://ift.tt/1K7NS7t

Asteroid 3122 Florence this week

Gianluca Masi of the Virtual Telescope Project acquired this image of asteroid 3122 Florence on August 28, 2017. See their livestream on August 31.

Gianluca Masi of the Virtual Telescope Project in Rome acquired this image of asteroid 3122 Florence on August 28, 2017. Named for Florence Nightingale, this asteroid is the biggest near-Earth object to pass this close since this category of objects was discovered over a century ago! It’s at least 2.7 miles (4.35 km) in diameter. It’ll safely pass by our planet on September 1, 2017 at over 18 times the Earth-moon distance.

The cool thing is that the asteroid will certainly be visible in small telescopes and might even be visible in binoculars; here are charts that can help you find it.

The Virtual Telescope Project will have a livestream of Florence’s close pass. The livestream is scheduled for August 31, 2017, starting at 19:30 UTC; translate to your time zone.

Thanks for the photo, Gian!

Bottom line: Photo of asteroid 3122 Florence, a large near-Earth object, which will pass Earth on September 1, 2017.



from EarthSky http://ift.tt/2vHRCZY

Gianluca Masi of the Virtual Telescope Project acquired this image of asteroid 3122 Florence on August 28, 2017. See their livestream on August 31.

Gianluca Masi of the Virtual Telescope Project in Rome acquired this image of asteroid 3122 Florence on August 28, 2017. Named for Florence Nightingale, this asteroid is the biggest near-Earth object to pass this close since this category of objects was discovered over a century ago! It’s at least 2.7 miles (4.35 km) in diameter. It’ll safely pass by our planet on September 1, 2017 at over 18 times the Earth-moon distance.

The cool thing is that the asteroid will certainly be visible in small telescopes and might even be visible in binoculars; here are charts that can help you find it.

The Virtual Telescope Project will have a livestream of Florence’s close pass. The livestream is scheduled for August 31, 2017, starting at 19:30 UTC; translate to your time zone.

Thanks for the photo, Gian!

Bottom line: Photo of asteroid 3122 Florence, a large near-Earth object, which will pass Earth on September 1, 2017.



from EarthSky http://ift.tt/2vHRCZY

Where’s the moon? 1st quarter

Here’s what a first quarter moon looks like. The terminator line – or line between light and dark on the moon – appears straight. Aqilla Othman in Port Dickson, Negeri Sembilan, Malaysia caught this photo on May 3, 2017. Notice that he caught Lunar X and Lunar V.

The moon reaches its first quarter phase on August 29, 2017, at 08:13 UTC. Full moon will be September 6 at 07:03 UTC; translate UTC to your time zone. Many will think of the September 6 full moon as the Harvest Moon, but others will say the Harvest Moon of 2017 falls in October. Read more about 2017’s Harvest Moon here.

A first quarter moon shows half of its lighted hemisphere – half of its day side – to Earth. At quarter moon, the moon’s disk is half-illuminated by sunlight and half-immersed in the moon’s own shadow.

We call this moon a quarter and not a half because it is one quarter of the way around in its orbit of Earth, as measured from one new moon to the next. Also, although a first quarter moon appears half-lit to us, the illuminated portion we see of a first quarter moon truly is just a quarter. We’re now seeing half the moon’s day side, that is. Another lighted quarter of the moon shines just as brightly in the direction opposite Earth!

Here’s a closer look at Lunar X and Lunar V. Photo taken May 3, 2017 by Izaty Liyana in Port Dickson, Negeri Sembilan, Malaysia. What is Lunar X?

And what about the term half moon? That’s a beloved term, but not an official one.

A first quarter moon rises at noon and is highest in the sky at sunset. It sets around midnight. First quarter moon comes a week after new moon. Now, as seen from above, the moon in its orbit around Earth is at right angles to a line between the Earth and sun.

As the moon orbits Earth, it changes phase in an orderly way. Follow these links to understand the various phases of the moon.

Four keys to understanding moon phases

Where’s the moon? Waxing crescent
Where’s the moon? First quarter
Where’s the moon? Waxing gibbous
What’s special about a full moon?
Where’s the moon? Waning gibbous
Where’s the moon? Last quarter
Where’s the moon? Waning crescent
Where’s the moon? New phase



from EarthSky http://ift.tt/1GsHF3c

Here’s what a first quarter moon looks like. The terminator line – or line between light and dark on the moon – appears straight. Aqilla Othman in Port Dickson, Negeri Sembilan, Malaysia caught this photo on May 3, 2017. Notice that he caught Lunar X and Lunar V.

The moon reaches its first quarter phase on August 29, 2017, at 08:13 UTC. Full moon will be September 6 at 07:03 UTC; translate UTC to your time zone. Many will think of the September 6 full moon as the Harvest Moon, but others will say the Harvest Moon of 2017 falls in October. Read more about 2017’s Harvest Moon here.

A first quarter moon shows half of its lighted hemisphere – half of its day side – to Earth. At quarter moon, the moon’s disk is half-illuminated by sunlight and half-immersed in the moon’s own shadow.

We call this moon a quarter and not a half because it is one quarter of the way around in its orbit of Earth, as measured from one new moon to the next. Also, although a first quarter moon appears half-lit to us, the illuminated portion we see of a first quarter moon truly is just a quarter. We’re now seeing half the moon’s day side, that is. Another lighted quarter of the moon shines just as brightly in the direction opposite Earth!

Here’s a closer look at Lunar X and Lunar V. Photo taken May 3, 2017 by Izaty Liyana in Port Dickson, Negeri Sembilan, Malaysia. What is Lunar X?

And what about the term half moon? That’s a beloved term, but not an official one.

A first quarter moon rises at noon and is highest in the sky at sunset. It sets around midnight. First quarter moon comes a week after new moon. Now, as seen from above, the moon in its orbit around Earth is at right angles to a line between the Earth and sun.

As the moon orbits Earth, it changes phase in an orderly way. Follow these links to understand the various phases of the moon.

Four keys to understanding moon phases

Where’s the moon? Waxing crescent
Where’s the moon? First quarter
Where’s the moon? Waxing gibbous
What’s special about a full moon?
Where’s the moon? Waning gibbous
Where’s the moon? Last quarter
Where’s the moon? Waning crescent
Where’s the moon? New phase



from EarthSky http://ift.tt/1GsHF3c

Lifesaving Balloon Catheter Device Added to Museum

A state of the art balloon catheter device was recently added to a military medical museum's collection. Find out how it works.

from http://ift.tt/2gmJNac
A state of the art balloon catheter device was recently added to a military medical museum's collection. Find out how it works.

from http://ift.tt/2gmJNac

Floods: Not just a coastal issue

Two people walk down a flooded section of Interstate 610 in floodwaters from Tropical Storm Harvey on Sunday, August 27, 2017, in Houston, Texas. Image via The Conversation/AP Photo/David J. Phillip.

By Nina Lam, Louisiana State University

Catastrophic flooding in Houston from Hurricane Harvey is the latest reminder that floods kill more people in the United States than any other type of natural disaster and are the most common natural disaster worldwide. Many communities along U.S. coastlines have begun to take heed and have slowed development in coastal flood zones. The bad news, as Harvey shows, is that inland communities are also at risk – and in some, development in flood zones is increasing.

With post-doctoral research associate Yi Qiang and graduate students, I recently studied development patterns in the United States from 2001 to 2011. We found that while new urban development in flood zones near coasts has generally declined, it has grown in inland counties. This is a worrisome trend. It implies that people who have experienced flooding on the coast migrate inland, but may not realize that they are still vulnerable if they relocate to an inland flood zone.

That’s what we have seen firsthand here in Louisiana. Thousands of people fled New Orleans after Hurricane Katrina in August 2005 and settled 80 miles inland in Baton Rouge. A decade later, many of these same people lost everything again when a 500-year flood event struck Baton Rouge in August 2016.

Climate change effects, such as sea level rise and potentially more extreme weather, are increasing the risk of flooding, hurricanes and storm surges in coastal areas. Some communities are considering moving coastal populations inland to protect them. However, our research shows that people should be very careful about moving inland. They can still face flood hazards if their property is located in a high-risk flood zone.

Damage from floods in Boulder County, Colorado, September 2013. Image via Steve Zumwalt/FEMA.

Not just a coastal issue

Flooding can happen wherever large rainstorms stall over an area, as we have seen in Boulder, Colorado in 2013; in Texas and Louisiana in 2016; and over Houston now. However, if communities take steps to reduce flood risk, they can mitigate the danger to people and property.

When we assess flood risk in a given location, we consider three questions.

– Hazard: How likely is a flood event?
– Exposure: How many people and physical assets are located there?
– Vulnerability: Do people have the capacity to deal with the event?

Flood risk is the product of these three elements.

We can decrease flood risk by reducing any of the three elements. For example, communities can reduce hazard by building flood control structures, such as dams and levees. They can use laws and policies, such as land use controls, to reduce exposure by steering housing development away from flood zones. And they can make people and property less vulnerable through other measures, such as elevating houses and developing better flood warning systems and emergency preparedness plans.

How can people learn about flood risks where they live? The Federal Emergency Management Agency has created flood zone maps for most parts of the United States. The maps are based on models that consider factors such as elevation, average rainfall and whether a location is near a river or lake that could overflow.

FEMA maps classify flood zones into three categories: high-risk, moderate-low risk and undetermined. High-risk zones have at least a 1 percent chance of being inundated by flood in any given year. These areas are also called base flood or 100-year flood zones.

To obtain a federally insured mortgage on property in a 100-year flood zone, buyers are required to have flood insurance. This policy is designed to make people less vulnerable in the event of a flood, but it increases the cost of home ownership. As a result, flood zone designations can be very contentious.

100-year flood zones are based on a combination of statistics, hydrogeology and society’s tolerance for risk.

Moving into harm’s way

We undertook this study because we wanted to develop a clear baseline showing how Americans’ exposure to flood hazards has changed over the past decade. To assess levels of exposure to flood hazards nationwide, we compiled urban development, flood zone and census data and overlaid them on a county map of the nation.

Overall, we estimated that as of 2011, more than 25 million Americans lived in flood zones. We also found that inland communities were less responsive to flood hazards than coastal communities and were doing a poorer job of steering development out of flood-prone areas.

The three U.S. counties with the largest concentrations of people living in flood zones are located on the Gulf of Mexico. They are Cameron Parish, Louisiana (population 6,401, with 93.6 percent in flood zones); Monroe County, Florida (population 66,804, with 91.4 percent in flood zones); and Galveston County, Texas (population 241,204, with 82.8 percent in flood zones).

These are all coastal communities, where flood risks should be well-known to all residents. But we also found inland counties where the share of the total population living in flood zones increased over the decade we examined. A number of those with the largest increases are bordered by rivers, such as Marshall County in western Kentucky, which sits between Kentucky Lake and the Ohio River. We also identified several hot spots where urban development has increased in coastal flood zones, including New York City and Miami.

Heavy rainfall from Tropical Storm Harvey is forecast to reach hundreds of miles inland. Image via National Weather Service.

Reducing exposure now

This alarming trend points to a need for more awareness, education and communication about flood risk, especially in inland counties. More affordable housing in nonflood zones and strategies to mitigate floods are also needed, especially inland.

Why would people move to inland flood zone areas? Some may be unaware of the risk. Others may plan to adapt through steps such as elevating their houses or buying flood insurance. Still other may accept the risk because they want to be closer to relatives or workplaces, or for other cultural, political or institutional reasons.

Our analysis has pinpointed a number of regions of concern. The next step is to produce in-depth analyses of these regions, in order to understand why people are locating in flood zones there, and to devise local strategies to reduce overall U.S. flood risks. Climate change, land subsidence or sinking, and construction of new levees and dams will change long-term flood exposure in these areas over time. Therefore, local governments, mortgage lenders and homeowners should review current FEMA flood hazard maps for accuracy.

The ConversationThis research provides national context for a detailed study that we are carrying out examining resilience and sustainability in the Mississippi River Delta. Our goal is to understand how human actions combined with natural environmental conditions may have caused land to sink in the Mississippi Delta. Our research on development in flood zones reminds us that flooding problems in low-lying coastal regions are not unique and also affect areas well away from the shore.

Nina Lam, Distinguished Professor of Louisiana Environmental Studies, Louisiana State University

This article was originally published on The Conversation. Read the original article.



from EarthSky http://ift.tt/2vo3g0L

Two people walk down a flooded section of Interstate 610 in floodwaters from Tropical Storm Harvey on Sunday, August 27, 2017, in Houston, Texas. Image via The Conversation/AP Photo/David J. Phillip.

By Nina Lam, Louisiana State University

Catastrophic flooding in Houston from Hurricane Harvey is the latest reminder that floods kill more people in the United States than any other type of natural disaster and are the most common natural disaster worldwide. Many communities along U.S. coastlines have begun to take heed and have slowed development in coastal flood zones. The bad news, as Harvey shows, is that inland communities are also at risk – and in some, development in flood zones is increasing.

With post-doctoral research associate Yi Qiang and graduate students, I recently studied development patterns in the United States from 2001 to 2011. We found that while new urban development in flood zones near coasts has generally declined, it has grown in inland counties. This is a worrisome trend. It implies that people who have experienced flooding on the coast migrate inland, but may not realize that they are still vulnerable if they relocate to an inland flood zone.

That’s what we have seen firsthand here in Louisiana. Thousands of people fled New Orleans after Hurricane Katrina in August 2005 and settled 80 miles inland in Baton Rouge. A decade later, many of these same people lost everything again when a 500-year flood event struck Baton Rouge in August 2016.

Climate change effects, such as sea level rise and potentially more extreme weather, are increasing the risk of flooding, hurricanes and storm surges in coastal areas. Some communities are considering moving coastal populations inland to protect them. However, our research shows that people should be very careful about moving inland. They can still face flood hazards if their property is located in a high-risk flood zone.

Damage from floods in Boulder County, Colorado, September 2013. Image via Steve Zumwalt/FEMA.

Not just a coastal issue

Flooding can happen wherever large rainstorms stall over an area, as we have seen in Boulder, Colorado in 2013; in Texas and Louisiana in 2016; and over Houston now. However, if communities take steps to reduce flood risk, they can mitigate the danger to people and property.

When we assess flood risk in a given location, we consider three questions.

– Hazard: How likely is a flood event?
– Exposure: How many people and physical assets are located there?
– Vulnerability: Do people have the capacity to deal with the event?

Flood risk is the product of these three elements.

We can decrease flood risk by reducing any of the three elements. For example, communities can reduce hazard by building flood control structures, such as dams and levees. They can use laws and policies, such as land use controls, to reduce exposure by steering housing development away from flood zones. And they can make people and property less vulnerable through other measures, such as elevating houses and developing better flood warning systems and emergency preparedness plans.

How can people learn about flood risks where they live? The Federal Emergency Management Agency has created flood zone maps for most parts of the United States. The maps are based on models that consider factors such as elevation, average rainfall and whether a location is near a river or lake that could overflow.

FEMA maps classify flood zones into three categories: high-risk, moderate-low risk and undetermined. High-risk zones have at least a 1 percent chance of being inundated by flood in any given year. These areas are also called base flood or 100-year flood zones.

To obtain a federally insured mortgage on property in a 100-year flood zone, buyers are required to have flood insurance. This policy is designed to make people less vulnerable in the event of a flood, but it increases the cost of home ownership. As a result, flood zone designations can be very contentious.

100-year flood zones are based on a combination of statistics, hydrogeology and society’s tolerance for risk.

Moving into harm’s way

We undertook this study because we wanted to develop a clear baseline showing how Americans’ exposure to flood hazards has changed over the past decade. To assess levels of exposure to flood hazards nationwide, we compiled urban development, flood zone and census data and overlaid them on a county map of the nation.

Overall, we estimated that as of 2011, more than 25 million Americans lived in flood zones. We also found that inland communities were less responsive to flood hazards than coastal communities and were doing a poorer job of steering development out of flood-prone areas.

The three U.S. counties with the largest concentrations of people living in flood zones are located on the Gulf of Mexico. They are Cameron Parish, Louisiana (population 6,401, with 93.6 percent in flood zones); Monroe County, Florida (population 66,804, with 91.4 percent in flood zones); and Galveston County, Texas (population 241,204, with 82.8 percent in flood zones).

These are all coastal communities, where flood risks should be well-known to all residents. But we also found inland counties where the share of the total population living in flood zones increased over the decade we examined. A number of those with the largest increases are bordered by rivers, such as Marshall County in western Kentucky, which sits between Kentucky Lake and the Ohio River. We also identified several hot spots where urban development has increased in coastal flood zones, including New York City and Miami.

Heavy rainfall from Tropical Storm Harvey is forecast to reach hundreds of miles inland. Image via National Weather Service.

Reducing exposure now

This alarming trend points to a need for more awareness, education and communication about flood risk, especially in inland counties. More affordable housing in nonflood zones and strategies to mitigate floods are also needed, especially inland.

Why would people move to inland flood zone areas? Some may be unaware of the risk. Others may plan to adapt through steps such as elevating their houses or buying flood insurance. Still other may accept the risk because they want to be closer to relatives or workplaces, or for other cultural, political or institutional reasons.

Our analysis has pinpointed a number of regions of concern. The next step is to produce in-depth analyses of these regions, in order to understand why people are locating in flood zones there, and to devise local strategies to reduce overall U.S. flood risks. Climate change, land subsidence or sinking, and construction of new levees and dams will change long-term flood exposure in these areas over time. Therefore, local governments, mortgage lenders and homeowners should review current FEMA flood hazard maps for accuracy.

The ConversationThis research provides national context for a detailed study that we are carrying out examining resilience and sustainability in the Mississippi River Delta. Our goal is to understand how human actions combined with natural environmental conditions may have caused land to sink in the Mississippi Delta. Our research on development in flood zones reminds us that flooding problems in low-lying coastal regions are not unique and also affect areas well away from the shore.

Nina Lam, Distinguished Professor of Louisiana Environmental Studies, Louisiana State University

This article was originally published on The Conversation. Read the original article.



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Old Faithful geyser at night

Old Faithful geyser in Yellowstone National Park, as captured by Yuri Beletsky Nightscapes in August, 2017.

One of the side benefits of last week’s eclipse has been that astrophotographers from around the globe came to the American West, especially around Wyoming, where the Astronomical League held its annual meeting (AstroCon 2017), just before eclipse day. Many astrophotographers then spent extra time in that part of the country, capturing photos of famous landmarks. Here’s a photo of Old Faithful geyser in Yellowstone National Park from one of our favorite photographers, Yuri Beletsky of Chile. He posted this at EarthSky Facebook on Sunday, August 27 and wrote:

Majestic Old Faithful under the stars in Yellowstone National Park :) I was truly fascinated by the scene! I’ve seen it so many times in text books and all over Internet, but it was my first time at the site. Watching it from such a close distance is a magical experience! On the images you can see numerous starts on the foreground including Polaris (upper right).

The foreground is actually illuminated by near artificial light coming from nearby hotels / facilities.

To suppress the light contamination, I used innovative ‘Clear Sky’ Optolong Filter for my Nikon D810a. Feel free to check it out if you’re in similar conditions. I hope you’ll enjoy it, too.

Thank you, Yuri!



from EarthSky http://ift.tt/2gm4uCN

Old Faithful geyser in Yellowstone National Park, as captured by Yuri Beletsky Nightscapes in August, 2017.

One of the side benefits of last week’s eclipse has been that astrophotographers from around the globe came to the American West, especially around Wyoming, where the Astronomical League held its annual meeting (AstroCon 2017), just before eclipse day. Many astrophotographers then spent extra time in that part of the country, capturing photos of famous landmarks. Here’s a photo of Old Faithful geyser in Yellowstone National Park from one of our favorite photographers, Yuri Beletsky of Chile. He posted this at EarthSky Facebook on Sunday, August 27 and wrote:

Majestic Old Faithful under the stars in Yellowstone National Park :) I was truly fascinated by the scene! I’ve seen it so many times in text books and all over Internet, but it was my first time at the site. Watching it from such a close distance is a magical experience! On the images you can see numerous starts on the foreground including Polaris (upper right).

The foreground is actually illuminated by near artificial light coming from nearby hotels / facilities.

To suppress the light contamination, I used innovative ‘Clear Sky’ Optolong Filter for my Nikon D810a. Feel free to check it out if you’re in similar conditions. I hope you’ll enjoy it, too.

Thank you, Yuri!



from EarthSky http://ift.tt/2gm4uCN