fall

More Extreme Wildfire Seasons | Earth Wise

April 29, 2020 By EarthWise Leave a Comment

According to a new study led by researchers at Stanford University, autumn in California feels more like summer now as a result of climate change, and this hotter and drier weather increases the risk of longer and more dangerous wildfire seasons.

The research team, whose work was recently published in the journal Environmental Research Letters, found that the frequency of extreme fire weather conditions in the fall in California has doubled since the early 1980s. Average temperatures during the season have increased by more than 2 degrees Fahrenheit, and rainfall has fallen by approximately 30%. The most pronounced warming has occurred in the late summer and early fall. That finding means that tinder-dry conditions coincide with the strong “Diablo” and “Santa Ana” winds that are typical in California at this time of year.

In recent years, these conditions have fed large and fast-moving wildfires across California. The state’s two largest wildfires, two most destructive wildfires, and the most deadly wildfire all occurred during 2017 and 2018, resulting in more than 150 deaths and $50 billion in damage.

Because summertime has typically been peak fire season, the recent spate of autumn fires is putting a strain on firefighting resources and funding. The ongoing COVID-19 pandemic could further strain emergency resources. Since fire-prone regions have historically shared wildfire-fighting resources throughout the year, the consequences of California’s extended wildfire season could have a global impact. (For example, California’s recent autumn wildfires have coincided with the beginning of wildfires in Australia).

The researchers highlight some opportunities to manage the intensifying wildfire risk in California, including limiting the trajectory of global warming in keeping with the targets identified in the United Nations’ Paris agreement.

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Researchers forecast longer, more extreme wildfire seasons

Photo, posted September 12, 2019, courtesy of the California National Guard via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Bird Migration And Climate Change | Earth Wise

January 22, 2020 By EarthWise Leave a Comment

A new study of bird migration shows the migration patterns are shifting as a result of climate change. Researchers at Colorado State University, the University of Massachusetts, and the Cornell Lab of Ornithology, looked at the impacts of climate change on a continental scale.

The team looked at the nocturnal migratory behaviors of hundreds of species representing billions of birds using radar and other data. They found that spring migrants are likely to pass certain stops earlier now than they would have 20 years ago. Temperature and migration timing are closely aligned and the greatest changes in migration timing are occurring in regions warming most rapidly. During the fall, shifts in migration were less apparent.

Migratory birds play an important role in ecosystems. They consume insects, disperse seeds, and perform various other significant functions. Birds serve as critical metrics of the health of ecosystems.

Bird migration is a global phenomenon that can provide unique visibility into changes in the climate. The ability to look at it on a global scale has only recently become practical as a result of big data technology and cloud computing. The team was able to crunch the numbers for the study in 48 hours, a task that previously would have taken over a year of continuous computing.

The findings have implications for understanding future patterns of bird migration because birds depend on food and other resources as they travel. As the climate changes, the timing of blooming vegetation or the emergence of insects may end up out of sync with the passage of migratory birds. This could have negative consequences for the health of migratory birds.

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Bird migration timing skewed by climate, new research finds

Photo, posted November 5, 2019, courtesy of Jerry Kirkhart via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Another Hot November

January 3, 2020 By EarthWise Leave a Comment

This past fall saw yet more of the high temperatures the world has been experiencing in recent times. Both the season (September through November) and the year to date were the second hottest in recorded history. November itself was the second-hottest November in the 140-year global climate record.

The high temperatures were felt at both ends of the world. Sea ice coverage across both the Arctic and Antarctic oceans fell to near-record lows in November. Arctic sea ice coverage was nearly 13% below the 1981-2010 average, while Antarctic coverage was 6.35% below average.

The average global land and ocean surface temperature for November was 1.66 degrees Fahrenheit above the 20^th century average. The year-to-date global temperature was 1.69 degrees Fahrenheit above the 20^th century average. These numbers correspond to almost a 1-degree Celsius increase, which should be compared with the Paris Climate Accord goal of keeping that increase to no more than 1.5 degrees.

November was the hottest November on record for South America, Africa, and the Hawaiian Islands. The Caribbean had its second-hottest November, and Europe had its seventh hottest on record.

The world’s average sea surface temperature ranked second warmest for the year to date and was only 0.05 degrees cooler than the all-time record.

The National Oceanic and Atmospheric Administration issues monthly global climate reports and for quite some time, these reports seem to all be the same. Another new record for heat or at least another near record. We have to expect that this trend will continue at least until the world starts making progress in dealing with its root cause.

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November 2019 was 2nd hottest on record for the planet

Photo, posted July 20, 2016, courtesy of Salehin Chowdhury via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Dangerous Cities For Migrating Birds

May 14, 2019 By EarthWise Leave a Comment

Billions of birds migrate north in the spring and south in the fall. The majority of them fly at night. But as they pass over large cities, the birds can become disoriented by bright artificial light – so-called light pollution, causing them to crash into buildings or windows.

Researchers estimate that 600 million birds die from building collisions in the United States every year. Now, a new paper from researchers at Cornell University reveals which metropolitan areas are most dangerous for birds and why.

The researchers ranked cities where, as a result of geography and exposure to light pollution, birds are at the greatest risk of becoming attracted to and disoriented by lights and crashing into buildings. They combined light pollution levels with bird density data in order to make their calculations. Their paper was recently published in the journal Frontiers in Ecology and the Environment.

Chicago, Houston, and Dallas finished as the three most dangerous cities for migrating birds. While migration routes vary depending on the season, these three cities still topped all others during both the spring and fall migrations due to their size and geographic positioning in the heart of North America’s most trafficked aerial corridors.

Audubon’s Lights Out program is one of several national efforts encouraging cities to reduce light pollution, particularly on heavy migration nights, in order to reduce bird mortality.

But homeowners need to do their part as well since an estimated quarter-million birds die from collisions with residential houses every year. The suggestion to cities and homeowners alike is the same: If you don’t need the lights, turn them off.

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Chicago tops list of most dangerous cities for migrating birds

Photo, posted May 18, 2017, courtesy of Pedro Szekely via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.