strain

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.

**********

Web Links

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.

Scientists first noticed in the 1970s that some frog populations were declining rapidly. By the 1980s, some species appeared to be extinct. The loss of frog species was mysterious because many were actually living in pristine habitats that did not face pollution or deforestation.

By the late 1990s, researchers had identified that frogs in widely different places around the world were infected with a deadly fungus called Batrachochytrium dendrobatidis – or Bd for short. The fungus originated on the Korean peninsula, but the pathogen spread throughout the world, probably via the international trade in pet amphibians. By 2007, researchers speculated that Bd might be responsible for all known declines of frogs that had no other apparent cause – about 200 species.

Recently, a group of 41 scientists published the first worldwide analysis of the fungal outbreak and the devastation turns out to be far worse than anyone had previously realized. Populations of more than 500 species of amphibians have declined significantly because of the outbreak, including at least 90 species presumed to have gone extinct. These figures are more than twice as large as earlier estimates.

According to biologists, Bd is now considered to be the deadliest pathogen known to science. But the decimation of frogs peaked in the 1980s. Today, although 39% of the species that suffered population declines in the past are still declining, 12% are showing signs of recovery, possibly because natural selection is favoring resistant animals.

There is cautious optimism for the surviving amphibian species, but scientists worry that another strain of Bd or some different species of fungus altogether may prove even deadlier. The best we can do is not participate in moving pathogens around the world.

**********

Web Links

The Plague Killing Frogs Everywhere Is Far Worse Than Scientists Thought

Photo, posted June 19, 2010, courtesy of Chris Luczkow via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.