spreading

Marine heatwaves are spreading

July 21, 2025 By EarthWise Leave a Comment

Sea surface temperatures broke records in 2024 and a quarter of the world’s oceans are experiencing temperatures that qualify as a marine heatwave. A marine heatwave is a prolonged period during which ocean temperatures are significantly warmer than average for that specific location and time of year.

Unusual heatwaves have occurred in all the major ocean basins around the planet in recent years and some have become so intense that they are being called super marine heatwaves.

The seas off the coasts of the UK and Ireland experienced an unusually intense and long-lasting marine heatwave starting in April. Australia was recently struck by heatwaves on two coasts.

Hotter oceans are causing drastic changes to marine life, sea levels, and weather patterns. Some of the most apparent casualties of ocean warming have been coral reefs. About 84% of reefs worldwide experienced bleaching-level heat stress at some point between January 2023 and March 2025.

Excess heat in the oceans can affect weather patterns, making hurricanes more likely to rapidly intensify and become more destructive.

A recent study published in Proceedings of the National Academy of Sciences concluded that climate change has been responsible for the overwhelming majority of marine heatwaves in recent decades.

People are learning to forecast these events. Eventually, parts of the ocean might enter a constant state of marine heatwave, at least by how it is defined today. Studying what is going on in the oceans today may provide insights into the future of the world’s oceans and provide guidance on how to try to achieve different outcomes.

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See How Marine Heat Waves Are Spreading Across the Globe

Photo, posted December 5, 2015, courtesy of Susanne Nilsson via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The warmer, greener Arctic and greenhouse gas

April 16, 2025 By EarthWise Leave a Comment

About 15% of the Northern Hemisphere is covered by permafrost. Permafrost is soil and sediment that has remained frozen for long periods of time, in some cases as much as 700,000 years. It contains large amounts of dead biomass that has accumulated over millennia and hasn’t fully decomposed. Therefore, permafrost is an immense carbon sink.

The Arctic is warming four times faster than the rest of the planet and, as a result, thawing permafrost is becoming a carbon source. As warming continues, ice is melting, and vegetation is spreading. A new study, published in Nature Climate Change, looked at the state of the Arctic and boreal north from the period 1990 until 2020. The study found that although half of the Arctic region has been growing greener, only 12% of those green areas are actually taking up more carbon. For one thing, the growth of forests means that there is more fuel for wildfires which are increasingly common.

A study of lakes in West Greenland found that thousands of crystal blue lakes have turned brown during record heat spells. Runoff from melting permafrost made the lakes opaque killing off plankton that absorb carbon dioxide. Meanwhile, plankton that release carbon dioxide multiplied. So, these lakes went from being carbon sinks to being carbon sources.

As the northern latitudes warm, ice and permafrost are melting, vegetation is spreading, and the region is becoming a source of heat-trapping gas after having been a place where carbon has been locked away for thousands of years. According to the Nature Climate Change study, roughly 40% of the Arctic is now a source of carbon dioxide.

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Warmer, Greener Arctic Becoming a Source of Heat-Trapping Gas

Photo, posted October 14, 2024, courtesy of Christoph Strässler via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The green grab for land

March 27, 2025 By EarthWise Leave a Comment

Solar and wind farms are spreading rapidly around the world. Many economists believe that solar power has crossed the threshold where it is generally cheaper than other ways to make electricity and will become the dominant energy source in the next couple of decades. As a result, both solar and wind farms are gobbling up more and more land around the world. Estimates are that they will take up around 30,000 square miles by mid-century.

One concern is whether we are entering an era of trading food for energy. Land conflicts seem inevitable since solar power operates best in unshaded areas with gentle winds and moderate temperatures, which are the same conditions favored by many crops.

China is installing more solar farms than the rest of the world combined. Many of these are in the Gobi Desert, where there is no competing need for the land. But some are in eastern China, in densely populated grain-growing areas.

There are a number of strategies that reduce the impact of solar farms on land use. One approach is to put them on old industrial or brownfield sites that are otherwise unusable. Another is floatovoltaics: putting solar panels on the surface of lakes and reservoirs. And then there is agrivoltaics, where solar panels are installed above crop fields or where livestock graze between or even beneath solar arrays. China has more than 500 agrivoltaic projects that incorporate crops, livestock, aquafarming, greenhouses, and even tea plantations.

Green energy has both environmental and economic benefits to offer, but it must conserve nature and not excessively grab land needed for people, wildlife, and ecosystems.

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‘Green Grab’: Solar and Wind Boom Sparks Conflicts on Land Use

Photo, posted May 25, 2011, courtesy of Michael Mees via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Species range and climate change

July 23, 2024 By EarthWise Leave a Comment

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

Fires Are Larger And More Frequent | Earth Wise

May 6, 2022 By EarthWise Leave a Comment

According to a new study by the University of Colorado Boulder, wildfires have gotten much larger and much more frequent across the United States since the year 2000. The rise in wildfires in recent years has been attributed to the changing climate and the new research shows that large fires have become more common and have been spreading into new areas that previously did not burn.

The researchers analyzed data from over 28,000 fires that occurred between 1984 and 2018 using satellite imagery along with detailed state and federal fire history records.

The results are that there were more fires across all regions of the contiguous U.S. from 2005 to 2018 compared to the previous 20 years. In the West and East, fire frequency doubled, and in the Great Plains, fire frequency quadrupled. The amount of land burned each year at least tripled in those regions.

The team discovered that the size of fire-prone areas increased in all regions of the contiguous U.S. in the 2000s, meaning that the distance between individual fires has been getting smaller than it was in previous decades and the fires have been spreading into areas that did not burn in the past.

This comprehensive study confirms what has been assumed by the media, public, and firefighting officials. The results also align with increasing risk trends such as the growing development of natural hazard zones. Projected changes in climate, fuel, and ignitions suggest that there will be more and larger fires in the future. More large fires plus intensifying development mean that the worst fire disasters are still to come.

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U.S. Fires Four Times Larger, Three Times More Frequent Since 2000

Photo, posted May 3, 2013, courtesy of Daria Devyatkina via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.