heat wave

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

Unexplained heat wave hotspots

December 27, 2024 By EarthWise Leave a Comment

2023 and 2024 have been the hottest years since records have been kept. But above and beyond the upward march of average temperatures around the globe, there has been the phenomenon of distinct regions across the globe experiencing repeated heatwaves that are so extreme that they cannot be accounted for in any models of global warming.

A new study by Columbia University’s Climate School has provided the first worldwide map of such regions, which have emerged on every continent except Antarctica. Heatwaves in these regions have killed thousands of people, withered crops and forests, and triggered devastating wildfires.

These recent regional-scale record-breaking temperature extremes have raised questions about whether current climate models can provide adequate estimates of the relationship between global mean temperature changes and regional climate risks.

Some of these regional events in recent years include a nine-day heatwave in the U.S. Pacific Northwest and southwestern Canada in June 2021 that broke daily records in some places by 54 degrees Fahrenheit. Across Germany, France, the UK, the Netherlands, and other countries, the hottest days of the year are warming twice as fast as the summer mean temperatures.

There is yet little understanding of the phenomenon. Some theories related to destabilization of the jet stream don’t really explain all the temperature extremes observed. But regardless of the underlying causes, the health impacts of these heat waves are severe, as are the effects on agriculture, vegetation, and infrastructure. Society is not built to quickly adapt to them.

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Unexplained Heat Wave ‘Hotspots’ Are Popping Up Across the Globe

Photo, posted August 16, 2022, courtesy of Alisdare Hickson via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

When is a heat wave just a heat wave?

December 18, 2024 By EarthWise Leave a Comment

There are lots of extreme weather events of all kinds these days. But there have always been extreme weather events. Climate change results in more extreme weather but not all extreme weather should be attributed to climate change. So, how do we know if an extreme weather event is a result of the changing climate? Communities that are affected by extreme weather events need to know whether they are likely to see more such events in the future, or if they are anomalies like a “500-year storm” or such.

Researchers at North Carolina State University, the National Oceanic and Atmospheric Administration, the University of Colorado, Boulder, and Princeton University developed a routine process for evaluating extreme weather events.

The test case was an extreme heat wave that affected Texas and Louisiana in 2023. This notable heat wave lasted almost the entire summer. The scientists used a two-step process to determine whether the heat wave was an anomaly or part of a new pattern. They took historical data from the past 100 years to see how unusual 2023 was. Then they compared that data with both past and present predictive computer models. Comparing the predictive models can indicate whether climate change was a factor in the event.

In this case, a similar drought would not have been as hot 50 years earlier, which indicates that the heat wave is related to climate change and that even more intense heat waves are likely to occur in the future.

This sort of information is important for communities to prepare for future events.

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When is a Heat Wave Just a Heat Wave, and When is it Climate Change?

Photo, posted July 22, 2006, courtesy of Saturnism via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Phoenix Is Frying | Earth Wise

August 15, 2023 By EarthWise Leave a Comment

The mythical Phoenix is a bird that repeatedly dies in a fire of its own making. During July, the five million inhabitants of greater Phoenix Arizona may have felt like they were reliving that myth as multiple temperature records were shattered in a massive heatwave.

On June 30, the high temperature in Phoenix was 110 degrees. From then on, the daily highs were relentlessly at or above 110 degrees, topping out at 119 on July 20. The previous record for consecutive days at or above 110 was 18 set in June 1974. The streak continued all the way until July 31, when incoming desert monsoons resulted in the high temperature dropping to 107 degrees – ending the streak at 31 days. Along the way, there were 16 days with temperatures at or above 115 degrees.

During the month, there were 17 consecutive days when the lowest temperature in Phoenix was at least 90 degrees. The previous record for that was 7 days, set in 2020. Because of these lofty low temperatures, July was also the hottest month in terms of average temperature with a reading well above 102 degrees. It was the first time that the average temperature has ever been in three digits. The previous record was 99.1 degrees in 2020.

Phoenix is an extreme case, but it was not alone in having a hot July. Globally, it was the hottest July on record that included major heat waves in the U.S., Mexico, China, southern Europe, and elsewhere. The daily record for the hottest average temperature on Earth ever measured was also broken several times during the month.

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Phoenix heat wave is shattering temperature records

Photo, posted September 22, 2022, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Record European Heat | Earth Wise

February 13, 2023 By EarthWise Leave a Comment

The new year began with record-breaking heat across Europe. In fact, on December 31 and January 1, about 5,000 all-time high temperature records for those dates were broken, in some cases by margins of more than 9 degrees Fahrenheit.

On New Year’s Day, eight European countries recorded their warmest January day ever. These were Liechtenstein, the Czech Republic, Poland, the Netherlands, Belarus, Lithuania, Denmark, and Latvia.

Many of the European cities affected by the heat wave would ordinarily be covered in snow at that time of year. For example, Vaduz, the capital of Liechtenstein, the Czech town of Javornik, and the Polish village of Jodlownik, all recorded peak temperatures between 66 and 68 degrees Fahrenheit.

By the measure of how far above normal temperatures rose, it was the most extreme heat wave in European history. Last summer saw record-breaking heat waves across much of Europe, but the actual temperature increases over normal were smaller than what just occurred at the beginning of the year.

The source of the exceptional heat was a warm mass of air from the west coast of Africa moving across Europe. As is the case for any individual weather event, one cannot definitively attribute this one to climate change. However, it is abundantly clear that because of climate change, extreme weather events of all types are becoming more frequent and more intense.

The unprecedented European weather does have the effect of helping to ease the energy crisis that has gripped the European continent. The Russian invasion of Ukraine has led to soaring natural gas prices. The warm weather has meant a lower demand for gas, causing gas prices to drop to their lowest level since the start of the war.

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‘Uncharted territory’: January heat records smashed across Europe

Photo, posted August 13, 2019, courtesy of Herbert Frank via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Vanishing Kelp Forests | Earth Wise

June 25, 2021 By EarthWise Leave a Comment

Bull kelp is the dominant species in offshore kelp forests north of Santa Cruz, California along the west coast of North America. Bull kelp has similar physical structures to terrestrial plants; it anchors to the ocean floor with root-like structures called holdfasts, and has stem-like structures called stipes from which leaf-like blades stretch out through the water, absorbing nutrients and sunshine.

These giant seaweeds form lush underwater forests in northern California’s coastal waters and have long provided critical habitat for many species like salmon, crabs, and jellyfish. But now, for much of the California coast, only a few patches of bull kelp remain.

A team from University of California Santa Cruz has studied satellite images of about 200 miles of coastline. They found that starting in 2014, the area covered by kelp has dropped by more than 95%.

The die-off was driven in part by an underwater heat wave that depleted nutrients in the water and made it harder for the kelp to grow. Making matters much worse, populations of purple sea urchins, which eat kelp, have exploded in the region because of overfishing and other reductions in urchin predators such as sea otters. The sea urchins eat kelp holdfasts, creating so-called urchin barrens where their destructive grazing has decimated kelp forests.

Bull kelp is a species at high risk of becoming endangered. In coming decades, more marine heatwaves are expected. These events as well as stronger El Niños will become more common and frequent with climate change. Between these thermal events and the sea urchins, it will be difficult for kelp forests to survive.

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Ninety-five percent of bull kelp forests have vanished from 200-mile stretch of California coast

Photo, posted October 28, 2015, courtesy of Florian Graner/Green Fire Productions via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Is There Hope For Coral Reefs?

January 16, 2019 By EarthWise Leave a Comment

News about the world’s coral reefs has been relentlessly bad for a number of years. Warming, acidifying oceans have wreaked havoc with coral reefs leading to enormous losses. Nowhere have things been more dire than in Australia’s Great Barrier Reef. Coral bleaching events have been increasingly common and severe over the past two decades. In fact, only 7% of the Great Barrier Reef has escaped bleaching entirely since 1998.

While the future of the world’s coral reefs is very much uncertain as global heating continues, there is a recent bit of hopeful news. According to a study published in Nature Climate Change, the response of the Great Barrier Reef to the extreme temperatures in 2017 was quite different from that of the previous year in the aftermath of back-to-back bouts of coral bleaching.

Surprisingly, corals that bleached in 2016 but managed to survive were more resistant to the recurrence of hot conditions in 2017.

Many corals don’t survive bleaching events at all and, of course,those corals don’t bleach for a second time. But the surviving corals from the 2016 bleaching event were tougher species. As a result of bleaching, the mix of coral species on the reef is changing very rapidly. The net result was that there was less bleaching in 2017 even though the temperatures that year were even more extreme than in 2016.

There have now been four mass bleaching events on the Great Barrier Reef over the past 20 years and it is only a matter of time before another one occurs triggered by the next marine heatwave. Almost half of the corals on the northern two-thirds of the reef have been killed. But at least some of the reef is showing impressive survival skills.

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A glimmer of hope for the world’s coral reefs

Photo, posted November 29, 2012, courtesy of Robert Linsdell via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Traffic Jams In The Jet Stream

July 13, 2018 By EarthWise Leave a Comment

Many extreme weather events are associated with unusual behavior by the jet stream. Jet streams are the global air currents that circle the earth. The meandering and speed changes in the jet stream affect weather and also play a big role in how long it takes aircraft to make their way across the country. The behavior that leads to extreme weather events is known as “blocking” in which the meandering jet stream stops weather systems from moving eastward.