By John Lawrence
August 2013 was prime time for wildfires. The Rim fire, started by a hunter’s illegal fire, burned 370 square miles in California. About a quarter of the fire was within Yosemite National Park. More than 5,100 firefighters were battling the flames at their peak. The Rim fire has destroyed 111 buildings, including 11 residences. It threatened San Francisco’s water supply. It has so far cost $72 million to fight and it’s still burning. Research in California’s Sierra Nevada found that rising average summer temperatures are strongly associated with an increase in acres burned. An annual increase in average summer temperature of 1º F is associated with a 35 percent growth in burned areas.
Nationally, federal agencies have spent more than $1 billion so far this year on wildfires, about half last year’s total of $1.9 billion. There have been 33,000 fires that have burned more than 5,300 square miles, an area nearly the size of Connecticut.
Jason Sibold, assistant professor of biogeography at Colorado State University, said that since the 1990’s, the climate has been changing, producing hotter, drier and longer summers in the West. That combined with more people building vacation homes in the woods pushes up costs. “The societal demand to try to control and fight these fires is escalating at the same pace as the climate’s warming,” he said.
Despite firefighting efforts, more than 960 homes and 30 commercial buildings have burned this year. And 30 firefighters have died in the effort, including 19 hotshots at Yarnell, Ariz. The annual average over the past 10 years is 17 dead per year.
Elsewhere, severe flooding has caused serious damage across southeast Asia affecting around 9 million people. Thailand was the worst hit. Close to 400 lives have been lost as the capital, Bangkok, was almost entirely submerged. Floods were caused by unusually heavy monsoonal rains. Prime Minister Yingluck has warned that the flood waters could stay for as long as a month. The Red Cross believes this will threaten to create a particular type of urban crisis in which public transport grinds to a halt, breaks in electricity leave the city sweltering in 95 degree F heat and 100% humidity, and the risks of mosquito-borne disease multiply. Crocodiles and venomous snakes are roaming freely.
Russia’s Amur River, which marks the border between Russia and China, has been subject to great flooding. The damage from the unprecedentedly powerful and protracted flooding in Russia’s Far East is estimated at $1 billion — and this is only a preliminary assessment, as there is no end in sight to the disaster.
Russia’s president Putin has visited the submerged areas. He flew over the endless spread of water in a helicopter and talked to local residents. “We have never experienced a catastrophe on this scale before,” Vladimir Putin said, instructing the Investigative Committee to check if officials’ actions during the flooding complied with the laws and regulations.
China’s province of Heilongjiang has been hit by summer floods and hailstorms which have affected 4.5 million people and resulted in 12 billion yuan ($1.9 billion) worth of damage. More than 60,000 homes were destroyed and 840,000 people evacuated from Heilongjiang, Jilin and Liaoning provinces due to flooding which happened at the same time as flooding in China’s southern Guangdong province. Nankouqian Township, one of the hardest-hit areas, saw 17.7 in of rain, half the average annual total, on August 16 alone. Almost 2 million acres of farm land were ruined in the region which depends heavily on farming. Power and communications lines were downed in several townships.
A new analysis of 12 extreme weather events in 2012 found “compelling evidence that human-caused change was a factor contributing to the event” in at least half of them, according to Thomas Karl, director of the Climatic Data Center at the National Oceanic and Atmospheric Administration (NOAA). Human influences are having an impact on some extreme weather and climate events, according to the report Explaining Extreme Events of 2012 from a Climate Perspective released September 5, 2013. Scientists from NOAA served as three of the four lead editors on the report.
The report shows that the effects of natural weather and climate fluctuations played a key role in the intensity and evolution of many of the 2012 extreme events. However, in several events, the analyses revealed compelling evidence that human-caused climate change was a secondary factor contributing to the extreme event. “This report adds to a growing ability of climate science to untangle the complexities of understanding natural and human-induced factors contributing to specific extreme weather and climate events,” said Karl. “Nonetheless, determining the causes of extreme events remains challenging.”