2003

Deadly Heatwaves On The Rise | Earth Wise

September 20, 2023 By EarthWise Leave a Comment

The European heatwave in the summer of 2003 resulted in at least 30,000 deaths with more than 14,000 in France alone. At the time, such a heatwave was considered to be a once-in-a-hundred-year event. But the warming climate is dramatically changing the odds for deadly heatwaves.

A new study by the ETH Institute in Zurich has found that the risk of fatal heatwaves has risen sharply over the past 20 years, and in the future, such extreme weather will become more frequent and heat-related excess mortality will increase, particularly in Europe. According to a paper published in Nature Medicine, more than 61,000 deaths in Europe could be blamed on the heat during the summer of 2022, which was the hottest summer on record for the continent. When the readings from this summer are analyzed, that record is likely to be surpassed.

Heatwaves lead to excess deaths due to dehydration, heat stroke, and cardiovascular collapse. They are particularly deadly for the elderly, the sick, and the poor. The ETH researchers analyzed comprehensive data from 748 cities and communities in 47 countries. They determined the relationship between increased temperature and excess mortality. Their models look at how excess mortality would develop with an average global temperature increase of 0.7 degrees Celsius (the value in 2000), 1.2 degrees (the value in 2020), and both 1.5 degrees (the limit sought by the Paris Agreement) and 2 degrees.

Even with the current global temperature, heatwaves that were a once-in-a-century event are now expected to occur every 10 years. With 2 degrees of warming, such heatwaves could happen every 2 to 5 years.

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Heatwaves are becoming more frequent and more deadly

Photo, posted July 22, 2009, courtesy of Matt McGee via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Glacial Loss In The Swiss Alps | Earth Wise

December 14, 2022 By EarthWise Leave a Comment

In 2022, glaciers in the Swiss Alps melted more than in any year on record. This is the latest piece of bad news for the country’s glaciers, which have lost more than half of their volume of ice since the 1930s.

The melting season for Switzerland’s snow and ice typically starts in May and ends in early October. This year’s melting season caused glaciers in the Diablerets mountain group to thin by an average of 13 feet, which is 3 times the amount of thinning observed over the past decade. The Tsanfleuron pass between two of the glaciers is now exposed as bare rock for the first time in several thousand years. Across Switzerland, glaciers lost about 6% of their remaining volume just this year. The previous worst year for glaciers was 2003, when losses were nearly 4%.

There was significant melting this year in part because of the small amount of snowfall over the winter. That snow melted quickly, being sped up by the warming effect of dust from the Sahara Desert falling on the snow. By early summer, there was no longer a protective blanket of snow on the glaciers, exposing them to summer heat.

The loss of glaciers is far more serious than the disappearance of aesthetically pleasing landscape features. Glaciers act as reservoirs of water that persist through the summer months. Melt from glaciers provides water to ecosystems and creates habitats for plants and animals. Cold runoff from glaciers affects downstream water temperatures which have a major impact on insects, fish, and other creatures. Globally, melting glaciers contribute more than 20% of the observed ongoing sea-level rise.

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Rocky Road for Swiss Glaciers

Photo, posted June 22, 2015, courtesy of Dennis Jarvis via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

A Record European Heatwave

August 1, 2019 By EarthWise Leave a Comment

Sahara Desert winds blasted Europe in June, especially during a five-day heatwave that set many records. Between that and weather elsewhere, June was not only one of the hottest ever for that continent, but also for the world as a whole.

In Europe, the average temperature was about 5 degrees Fahrenheit above the June average of a century ago. The global temperature was nearly 2 degrees Fahrenheit higher.

The European heatwave broke temperature records in France, Switzerland, Austria, Germany, and Spain. A temperature above 114 degrees was recorded near the French city of Nîmes.

The intense heat lead to wildfires in Spain and Germany, and widespread disruption across Europe. Undoubtedly, the heatwave has caused many premature deaths, but it will take some time to compile those statistics. The European heatwave of 2003 caused more than 70,000 premature deaths.

According to calculations by climate scientists, the record-breaking heatwave in June was made at least 5 and as much as 100 times more likely by climate change. Global heating caused by the carbon emissions from burning fossil fuels and other human activities means that heatwaves are becoming more probable and severe. So-called attribution studies estimate how much more likely and severe such events are.

The researchers used temperature records stretching back to 1901 to assess the probability of a heatwave last month and in the past. They also examined climate change models to assess the impact of global heating. More than 230 attribution studies to date around the world have found that 95% of heatwaves were made more likely or worse by climate change.

It was the hottest June on record in Europe by a country mile and there are likely to be more months like it in the future.

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Climate Change Made Last Month’s European Heatwave At Least Five Times More Likely

Photo, posted February 13, 2018, courtesy of Guilhem Vellut via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.