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Species range and climate change

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The geographic range of a particular plant or animal species is the area in which it can be found during its lifetime.  The range of most species is limited by climatic factors, including temperature, precipitation, soil moisture, humidity, and wind.  Any changes in the magnitude or variability of these factors will impact the species living there. 

For example, a species sensitive to temperature may respond to a warmer climate by moving to cooler locations at higher latitudes or elevations. 

But not all species are able to move at the same speed.  According to an international research team led by scientists from the University of Massachusetts Amherst, non-native species are expanding their ranges many times faster than native species.

The researchers found that land-based plant and animal species need to be shifting their ranges by about two miles per year just to keep up with the rapid pace of the changing climate.  Marine species need to be moving about 1.7 miles per year.  However, native species are only managing to move about one mile per year on average.  

Non-native species, on the other hand, are spreading nearly 22 miles each year on their own.  Additionally, when the role humans play in assisting the spread of non-native species is factored in, the rate jumps to a whopping 1,170 miles per year.  This is more than 1,000 times faster than the rate at which native species are spreading.   

The researchers conclude that there is no chance for native species to keep up with climate change without human help.  Assisted migration needs to be on the table if native plants and animals are to survive.   

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Non-Native Plants and Animals Expanding Ranges 100 Times Faster than Native Species

Photo, posted April 10, 2011, courtesy of Bri Weldon via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Grid-Scale Gravity Energy Storage | Earth Wise

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As wind and solar energy play a growing part in our energy system, the need for grid-scale energy storage is growing as well.  An historic form of energy storage and still the largest in installed capacity is pumped hydro storage, which makes use of the potential energy contained in having water sitting at a higher elevation where it can be released downward to operate turbine generators.  This is an effective system but is limited to places where geography cooperates.

For the past five years, a company called Energy Vault has been developing a system that uses the same principle to generate electricity but instead of pumping water to a higher elevation, it uses mechanical devices to lift heavy objects such as concrete blocks to an appropriate height.  Lowering the blocks back to the ground drives generators.

To date, Energy Vault has only built demonstration systems with a fraction of the storage capacity needed for grid-scale operation. Their EV1 Tower in Switzerland was successfully grid interconnected in 2020 and demonstrated round-trip efficiency (the fraction of the energy stored that was produced by the generators) above 75%.  Their improved EVx system is expected to do better than 80%.

This year the company, along with partners Atlas Renewable and China TIanying, is now in the first phases of commissioning a grid-scale system located outside of Shanghai, China.  The 25-MW system is built adjacent to a wind farm and a national grid interconnection site

This is the first grid-scale gravity energy storage system and is expected to be fully online in the fourth quarter of this year.  A second, similar system is now under contract to be built elsewhere in China.

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First grid-scale gravity energy storage system undergoes commencement in China

Photo courtesy of Energy Vault.

Earth Wise is a production of WAMC Northeast Public Radio

Keeping The Keeling Curve Going | Earth Wise

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The world’s longest-running record of direct readings of carbon dioxide levels in the atmosphere is the Keeling Curve, measurements taken at the summit of Mauna Loa in Hawaii.  The readings have been going on with almost no interruption since Charles Keeling began taking them in the 1950s.  But the eruption of Mauna Loa last November toppled power lines at the mountaintop observatory and buried a mile of the main road up the mountain in lava.

Scientists have been scrambling to resume measurements and the near-term solution has been to take them, for the first time, on Mauna Kea, the neighboring large volcano about 25 miles away.  The National Oceanic and Atmospheric Administration flew in and installed instruments at the Mauna Kea observatory so that only about a week went by without measurements.   It happened so quickly because months earlier, NOAA had already started looking into installing a backup site on Mauna Kea where there is an observatory run by the University of Hawaii.

NOAA used helicopters to install solar panels and batteries on Mauna Loa to restore power in the short term since it will be months before a new road can be built on the still-cooling lava. The plan is to collect parallel measurements for a year to see if Mauna Kea, which hasn’t erupted for thousands of years, might become a long-term backup for Mauna Loa.

The Hawaiian volcanoes are uniquely suited for the measurements because they are surrounded by thousands of miles of empty ocean and are very high up, away from towns, cars, and forests.  Scientists are now monitoring measurements from the two sites to see how they compare.

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Battling Lava and Snowstorms, 2.5 Miles Above the Pacific

Photo, posted November 2, 2015, courtesy of Neal Simpson via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Climate Change And The Color Of Lakes | Earth Wise

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According to a new study recently published in the journal Geophysical Research Letters, blue lakes around the world are at risk of turning green-brown if climate change continues unabated. 

For the study, the research team used over five million satellite images of more than 85,000 lakes and reservoirs around the globe between 2013 and 2020 in order to determine each lake’s most common water color.  Since lake color can change seasonally, the researchers assessed the most frequent lake color during those seven years. 

Algae and sediments affect the color of lakes.  But the study found that precipitation, air temperature, lake depth, and elevation also play major roles in determining a lake’s most common water color. 

The research team found that blue lakes account for less than one-third of lakes worldwide.  Blue lakes tend to be deeper and are often found in cool, high latitude regions with high precipitation and winter ice cover.  Meanwhile, green-brown lakes, which account for 69% of all lakes, are found in drier regions, continental interiors, and along coastlines. 

As global temperatures rise, lakes will warm, and warmer water produces more algal blooms.  As a result, the researchers expect the changing climate to decrease the percentage of blue lakes, many of which are found in the Rocky Mountains, northeastern Canada, northern Europe and New Zealand. 

Water color is a simple but viable way to measure water quality that can be done on a global scale using satellites.  This approach provides researchers with a way to study how lakes – even the remote ones – are changing.  

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Climate change is making lakes turn green-brown

Photo, posted August 27, 2011, courtesy of Paul Schultz via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The Great Salt Lake Is Disappearing | Earth Wise

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Utah’s Great Salt Lake is the largest saltwater lake in the western hemisphere.  According to data from the US Geological Survey, the surface water elevation of the Great Salt Lake has fallen to the lowest level since records began in the mid-1800s.  The average elevation is now 4,190 feet above sea level.   With this drop in water level, the surface area of the lake is little more than half of its historical size.  The lower water level has exposed about 700 square miles of previously submerged lakebed.

The lake now contains about a quarter of the volume of water that it did at its high point in 1987.  The precipitous drop in water is a result of water usage from the lake coupled with climate change-fueled drought.   Increased water demand is due to the rapidly growing population of metropolitan Salt Lake City.  Utah’s population is projected to increase by almost 50% by 2060.

The Great Salt Lake goes though seasonal cycles of water loss and replenishment.  Rain and snow generally refill its level.  However, because of the ongoing megadrought in the West, water evaporation and depletion continue to exceed the amount of water entering the lake.  The water levels are expected to further decrease until fall or early winter, when incoming water is expected to equal or exceed evaporation.

The decline of the Great Salt Lake is a serious threat to the economy, ecology, and people of northern Utah.  The lake generates snowpack, is a refuge for hundreds of migratory birds and other wildlife and generates millions of dollars in the economy through mineral extraction and tourism.

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Utah’s Great Salt Lake is disappearing

Photo, posted October 6, 2020, courtesy of Julie Girard via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Clouds And Global Warming | Earth Wise

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Recent climate models from multiple organizations project that the amount of warming that doubling atmospheric carbon dioxide would cause would be much more than previously estimated.  And one of the significant changes to the models relates to the role of clouds.

Clouds have long been a major uncertainty in climate calculations.  Clouds can shade the earth and thereby provide cooling.  But clouds can also trap heat.  Which effect dominates depends on how reflective the clouds are, how high up they are, and whether it is day or night.  The dynamics of clouds are complicated.

If you fly across the ocean, you will see blankets of low clouds extending for hundreds of miles.  These marine stratus and stratocumulus clouds predominantly cool the Earth.  In fact, they shade roughly a fifth of the oceans and reflect 30-60% of the solar radiation that hits them back into space.

Recent studies indicate that as global temperatures rise, these clouds are likely to become thinner or burn off entirely, leaving more clear skies through which the sun may add another degree Celsius or more to global warming.

The concerns about clouds are part of the larger issue about feedbacks in warming the world.  It has long been clear that the greenhouse effect of doubling CO2 levels in the atmosphere would raise global temperature.  But there are amplifying feedback effects.  Melting large areas of snow and ice reduces reflectivity and allows the land and oceans to absorb more heat.  More water vapor entering the atmosphere traps more heat.  And now clouds are another concern.

Overall, these effects are leading to climate models predicting much larger global temperature increases, which is a scary prospect for the world.

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Why Clouds Are the Key to New Troubling Projections on Warming

Photo, posted September 10, 2006, courtesy of Nicholas A. Tonelli via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Rising Seas Will Erase Cities

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According to new research, climate-driven sea level rise could affect three times more people by 2050 than previously thought.  This sobering assessment means some of the world’s great coastal cities, including Bangkok, Shanghai, Mumbai, Basra, Alexandria, and Ho Chi Minh City, could be in big trouble.   

Scientists have always relied on land elevation data to determine the effects of sea level rise over large areas.  But standard elevation measurements using satellites struggle to differentiate the true ground level from the tops of trees or buildings.  The authors of the paper developed a more accurate way to calculate land elevation by using artificial intelligence to determine the error rate and to correct for it.  The new findings revealed that 150 million people – three times more than previously thought – are now living on land that is projected to be below the high-tide line by the middle of this century. 

Eight Asian nations – China, Bangladesh, India, Vietnam, Indonesia, Thailand, the Philippines, and Japan – account for about 70% of the people living on at-risk land. 

More than 20 million people in Vietnam, including much of Ho Chi Minh City, live on land that will be inundated by 2050.  In Thailand, more than 10% of its citizens, including much of Bangkok, currently live on land imperiled by projected sea level rise. 

This new research was produced by Climate Central, a New Jersey-based science organization, and was recently published in the journal Nature Communications. 

Sea level rise is clearly not just an environmental problem.  It’s a humanitarian crisis.

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New elevation data triple estimates of global vulnerability to sea-level rise and coastal flooding

Rising Seas Will Erase More Cities by 2050, New Research Shows

Photo, posted December 18, 2009, courtesy of Misko via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Cleaning Up Mount Everest

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Mount Everest is the highest mountain above sea level with an elevation over 29,000 feet.  As such, it is a prime attraction for mountain climbers seeking that ultimate achievement.  The summit was first reached in 1953 and for a long time, only major expeditions by the best mountaineers sought to repeat the feat.

In recent years, climbing Everest has become much more common.  In fact, since 1953, more than 4,000 people have reached the summit of the world’s highest mountain.  A record 807 accomplished the feat last year alone.  Thousands more visit lower elevations.

But climbing Everest is neither safe nor easy.  Ice and snow, powerful winds, and generally harsh conditions make Everest a treacherous place.  Over the decades, hundreds of climbers have died on its slopes and many of their bodies are still up there.  Apart from human remains, there are decades worth of garbage left behind by hikers and tourists.

The government of Nepal has mounted an ambitious project to clean up the refuse on Mount Everest.  In just the first two weeks, volunteers removed more than three tons of trash from the mountain. Among the rubbish removed from Everest are tents, climbing equipment, bottles, cans, empty oxygen containers, and human waste.  They also discovered the bodies of four climbers that had emerged from melting snow and ice.

Helicopters carried a third of the garbage to Kathmandu for recycling.  The rest was taken to a local district for disposal in landfills.  The initial work started at Everest’s base camp.  They are next moving to sites higher on the mountain.  They hope to remove at least 10 tons of trash this year.

Nepal would like to make the world’s tallest mountain clean.

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Volunteers Remove 3 Tons of Trash From Mount Everest in Two Weeks

Photo, posted May 23, 2012, courtesy of Gunther Hagleitner via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

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