water bodies

Amphibians and climate change

April 7, 2025 By EarthWise Leave a Comment

Amphibians are a group of vertebrate animals that include frogs, toads, and salamanders. They are unique for their ability to live both in water and on land during different stages of life. Amphibians play a crucial role in ecosystems, often serving as both predators and prey in food webs.

Amphibians are the world’s most at-risk vertebrates, with more than 40% of species listed as threatened. They are cold-blooded creatures and rely on external sources to regulate their body temperature. But needing to regulate their body heat this way makes amphibians particularly vulnerable to temperature change in their habitats.

Researchers from the University of New South Wales in Australia can now predict the heat tolerance of 60% of the world’s amphibian species. This new tool will allow scientists to better identify which amphibian species and habitats will be most impacted by climate change.

The study’s landmark findings, which were recently published in the journal Nature, found that 2% of amphibian species are already exposed to overheating in shaded terrestrial conditions. According to the research team, a 4°C global temperature increase could push 7.5% of amphibian species beyond their physiological limits.

Local amphibian extinctions can trigger ecological repercussions, including reshuffling community compositions, eroding genetic diversity, and impacting the food chain and overall ecosystem health.

The researchers highlight the importance of vegetation and water bodies in protecting amphibians during heat waves, and emphasize the need to provide adequate water and shade during future conservation efforts.

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The pot is already boiling for 2% of the world’s amphibians: new study

Photo, posted October 8, 2011, courtesy of Dave Huth via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The Atmosphere Is Thirstier | Earth Wise

May 9, 2022 By EarthWise Leave a Comment

The American West is in the throes of a two-decade-long drought. The climate there is getting warmer and drier, which has led to increasing demand for water resources from both humans and ecosystems. According to a new study by the Desert Research Institute and collaborators, the atmosphere across much of the U.S. is also demanding a greater share of water than it used to.

Evaporative demand, which is also called atmospheric thirst, is a measure of the potential loss of water from the earth’s surface up to the atmosphere. It is a function of temperature, humidity, wind speed, and solar radiation. The study, published in the Journal of Hydrometeorology, assessed trends in evaporative demand during a 40-year period from 1980-2020.

The study’s findings showed substantial increases in atmospheric thirst across much of the Western U.S. over that period, with the largest increases centered around the Rio Grande and Lower Colorado rivers. This is important because atmospheric thirst is a persistent force in pushing Western landscapes and water supplies toward drought.

The study found that, on average, increases in temperature were responsible for 57% of the changes observed in atmospheric thirst, humidity 26%, and the other factors playing lesser roles.

For farmers and other water users, increases in atmospheric thirst mean that, in the future, more water will be required to meet existing water needs. Crops already require more water than they did in the past and can be expected to require more water in the future. Over time, for every drop of precipitation that falls, less and less water is likely to drain into streams, wetlands, aquifers, or other water bodies.

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New study shows robust increases in atmospheric thirst across much of U.S. during past 40 years

Photo, posted August 9, 2007, courtesy of William Clifford via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Renewable Natural Gas

September 30, 2019 By EarthWise Leave a Comment

Small-scale biogas systems have collected methane from landfills, sewage plants, and farms for decades. Here in the US, biogas is finally catching up with modern techniques with the advent of third-party operators introducing more sophisticated technology to capture methane and pump it directly into pipelines.

Renewable methane or natural gas represents a significant mostly unexploited source of energy. Examples include the vast amounts methane generated by manure from some of the 2,300 hog farms in eastern North Carolina, biodigesters that can turn clusters of large California dairy farms into energy hubs, as well as diverting food waste from landfills and transforming it into vehicle and heating fuels.

According to a 2014 EPA study, the U.S. could support at least 13,000 biogas facilities, fed by manure, landfill gas, and biosolids from sewage treatment plants. Those facilities could produce over 650 billion cubic feet of biogas per year – enough renewable energy to power 3 million homes.

A study by the World Resources Institute estimated that the 50 million tons of organic waste sent to landfills or incinerated every year in the U.S. has the energy content of 6 billion gallons of diesel fuel, amounting to 15% of all diesel consumed by heavy-duty trucks and buses.

Utilizing all that biogas could help lower greenhouse gas emissions from some of the most difficult sectors to decarbonize – transportation, industry, and heating buildings. In addition, ramped up renewable gas could keep organic waste out of landfills and prevent manure runoff into rivers and water supplies.

Renewable natural gas could be the next big thing in green energy.

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Could Renewable Natural Gas Be the Next Big Thing in Green Energy?

Photo, posted June 19, 2013, courtesy of Alan Levine via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.