northern latitudes

2023: A year of extreme climate

September 11, 2024 By EarthWise 1 Comment

There have already been all sorts of extreme weather this year in many parts of the world and undoubtedly there will be more to talk about in the coming months. But the American Meteorological Society has recently published its State of the Climate report for 2023 and it was a year for the record books.

In 2023, the Earth’s layers of heat-reflecting clouds had the lowest extent ever measured. That means that skies were clearer around the world than on average, a situation that amplifies the warming of the planet. Since 1980, clouds have decreased by more than half a percent per decade.

The most dramatic climate effect last year occurred in the world’s oceans. About 94% of all ocean surfaces experienced a marine heatwave during the year. The global average annual sea surface temperature anomaly was 0.13 degrees Celsius above the previous record set in 2016. This is a huge variation for the ocean. Ocean heatwave conditions stayed in place for at least 10 months in 2023 in vast reaches of the world’s oceans. Ocean heat was so remarkable that climate scientists are now using the term “super-marine heatwaves” to describe what is going on.

There were many other ways in which 2023 experienced weather extremes. July experienced a record-high 7.9% of the world’s land areas in severe drought conditions. During the year, most of the world experienced much warmer-than-average conditions, especially in the higher northern latitudes. These unprecedented changes to the climate are unlikely to be one-time occurrences; 2024 is likely to be another one for the record books.

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New Federal Report Details More of 2023’s Extreme Climate Conditions

Photo, posted May 27, 2021, courtesy of Wendy Cover/NOAA via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Overwintering Fires | Earth Wise

July 6, 2021 By EarthWise Leave a Comment

Fires that go on for long periods of time, surviving the snow and rain of winter to reemerge in the spring, are becoming more common in high northern latitudes as the climate warms. Such fires are called holdover fires, hibernating fires, overwintering fires, or even zombie fires. Whatever people choose to call them, this type of wildfire is occurring more often.

These smoldering fires start out as flaming fires but then enter an energy-saver mode. They start above ground but then smolder in the soil or under tree roots through the winter. They barely survive based on the oxygen and fuel resources that they have but can transition back into flaming fires once conditions are more favorable.

Dutch researchers used ground-based data with fire detection data from NASA’s Moderate Resolution Imaging Spectroradiometer instruments on the Terra and Aqua satellites to study fires in the boreal forests of Alaska and Canada’s Northwest Territories. They found a way to identify overwintering fires based on their unique characteristics.

Their data indicates that overwintering fires tend to be linked to high summer temperatures and large fire seasons. Between 2002 and 2018, overwintering fires generally accounted for a small amount of the total burned area in the region but in individual years with hot and severe fire seasons, the number can escalate. In 2008 in Alaska, for example, overwintering fires accounted for nearly 40% of the burned area.

Early detection of these overwintering fires could help with fire management and reduce the amount of carbon – which is stored in large amounts in the region’s organic soils – that gets released to the atmosphere during fires.

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Overwintering Fires on the Rise

Photo, posted September 14, 2017, courtesy of Andrew R. Mitchell/USDA via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Shrinking Arctic Glaciers

March 18, 2019 By EarthWise Leave a Comment

The glaciers on Baffin Island, located in Canada’s northeastern Arctic, have been shrinking as the climate warms. The melting, receding glaciers have exposed fragments of ancient plants that had frozen in the places where they once grew. New research has shown that these spots have not seen the light of day for at least 40,000 years.

The entire planet has been warming since humanity started flooding the atmosphere with greenhouse gases at the start of the Industrial Revolution, but the effects are not uniform across the globe. Some regions – like the Arctic – are seeing temperature rises that are greater and faster than anywhere else in the world. As a result, glaciers in the Arctic have been melting away at rates never before observed in modern human history.

Researchers at the University of Colorado performed radiocarbon dating experiments in order to find out when the last time was that the Arctic was as warm as today. There have been natural variations in Arctic temperatures caused by the complicated way the Earth wobbles on its axis. For example, 10,000 years ago the northern latitudes pointed at the sun more directly during the summer than they do now, providing about 9% more sunshine during the summer.

The results of the study showed that the newly-uncovered plants had died at least 40,000 years earlier, indicating that the glaciers had not melted back to today’s size for at least that long. Global measurements indicate that the planet as a whole has not been as warm as it is today for about 115,000 years, back then again a result of the orientation of the Earth.

Well, the Earth hasn’t wobbled recently. The Arctic is melting because we are dumping massive amounts of greenhouse gases into the atmosphere.

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These Arctic glaciers are smaller than ever before in human history

Photo, posted September 1, 2010, courtesy of Doryce S. via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.