Experts believe climate change will feed wildfires worldwide


 
04 August 2017

published by http://www.fireandrescue.co


Global - Out-of-control wildfires, like the ones that brought destruction to southern Europe, North America and parts of South Africa in recent weeks, will likely become more frequent as global temperatures soar under climate change, experts say. More than 10 000 people had to flee raging fires in southern France recently and several villages were evacuated in Portugal just weeks after another blaze killed more than 60 people there. In South Africa, nine people died and some 10 000 people were evacuated from their homes as fires raged through the drought-stricken Western Cape in June 2017. During July 2017, some 40 000 people had to flee wildfires in western Canada, where officials declared a state of emergency. In California, about 8 000 people were recently evacuated ahead of fires that razed vast swathes of forest. Long periods of heat cause vegetation to become dry and inflammable, making it easily set alight by lightning, spontaneous combustion or fires lit by humans. The more the mercury climbs, the higher the risk for more wildfires. Scientists say the average global temperature has risen by one degree Celsius since the Industrial Revolution, when industrial activity started emitting heat-trapping greenhouse gases from burning fossil fuels into the atmosphere.

Most of the world’s nations agreed in Paris in 2015 to limit overall warming to two degrees Celsius but experts say this will not be enough and that severe heatwaves and drought will grow worse regardless. It is not just the heat that’s to blame for fires. A recent study showed that extreme thunderstorms formed due to higher temperatures and were the main driver for massive fires in Alaska and Canada in recent years. More storms mean more lighting to ignite fires. Signs are the climate is right for divesting from the fossil fuel industry.

According to Thomas Curt, a researcher at France’s Irstea climate and agriculture research institute, big fires of more than 100 hectares and “mega-fires" of more than 1 000 hectares have been a growing problem worldwide, notably in Mediterranean Europe. Research by the National Aeronautics and Space Administration (NASA) shows that fires have increased in Canada and the American west, as well as in regions of China, India, Brazil and southern Africa. According to NASA, a warming and drying climate was to blame, with climate change increasing fire risk in many regions.

The United Nations’ World Meteorological Organisation (WMO) said in June 2017 that parts of Europe, the Middle East, north Africa and the south-western United States experienced extremely high temperatures in May and June 2017. Globally, surface temperatures over land and sea were the second highest on record for January to May 2017. Italy, Portugal and most of France had winter rainfall 20 to 30 percent less than the seasonal norm, according to French climatologist Michele Blanchard.

Almost three quarters of Portugal, where 75 000 hectares of forest have burnt since January 2017, has been battling a severe drought since June 2017. According to the WMO, more than a third of Portuguese weather stations measured temperatures higher than 40 degrees Celsius over a weekend in June 2017 when the fires began. In France, several towns in the south broke June temperature records. Large parts of South Africa, meanwhile, experienced a historic drought and crippling water shortages.

Scientists are loathe to ascribe any particular drought, heatwave or other weather event to climate change, as this is a phenomenon that can only be measured over decades. However, they note that these events took place within an overall warming trend. “Climate change will unlock more heatwaves, with more evaporation and more intense drought," said Blanchard.

A 2016 study of the European Commission showed that the fire-prone surface area of southern Europe could double in the 21st century. A study published in Nature Climate Change in June 2017 said three quarters of the global population will be exposed to potentially deadly heatwaves by 2100 unless greenhouse gas emissions are curbed. Even with aggressive cuts, it said, nearly half of the population will be exposed.

According to the authors of another study published by the same journal in May 2017, fire is the most significant risk to forests, which cover about a third of global land surface. And it was clear that risks caused by fires will increase in the context of climate change, they said, citing devastating forest blazes in Canada and Russia in recent years.

Apart from long-term efforts to rein in global warming, some forests will have to be cut back, undergrowth cleared, and residential areas moved further from scrubland and forest borders to reduce the risk to life and property. "The focus should shift from combating forest fires as they arise to preventing them from existing, through responsible long-term forest management," said the World Wide Fund for Nature.

An international team of climate researchers from the US, South Korea and the UK has developed a new wildfire and drought prediction model for southwestern North America. Extending far beyond the current seasonal forecast, this study published in the journal Scientific Reports could benefit the economies with a variety of applications in agriculture, water management and forestry.

Over the past 15 years, California and neighboring regions have experienced heightened conditions and an increase in numbers with considerable impacts on human livelihoods, agriculture, and terrestrial ecosystems. This new research shows that in addition to a discernible contribution from natural forcings and human-induced global warming, the large-scale difference between Atlantic and Pacific ocean temperatures plays a fundamental role in causing droughts, and enhancing wildfire risks.

"Our results document that a combination of processes is at work. Through an ensemble modeling approach, we were able to show that without anthropogenic effects, the droughts in the southwestern United States would have been less severe," says co-author Axel Timmermann, Director of the newly founded IBS Center for Climate Physics, within the Institute for Basics Science (IBS), and Distinguished Professor at Pusan National University in South Korea. "By prescribing the effects of man-made climate change and observed global ocean temperatures, our model can reproduce the observed shifts in weather patterns and wildfire occurrences."



Read more at: https://phys.org/news/2017-07-atlanticpacific-ocean-temperature-difference-fuels.html#jCp
An international team of climate researchers from the US, South Korea and the UK has developed a new wildfire and drought prediction model for southwestern North America. Extending far beyond the current seasonal forecast, this study published in the journal Scientific Reports could benefit the economies with a variety of applications in agriculture, water management and forestry.
 

Over the past 15 years, California and neighboring regions have experienced heightened conditions and an increase in numbers with considerable impacts on human livelihoods, agriculture, and terrestrial ecosystems. This new research shows that in addition to a discernible contribution from natural forcings and human-induced global warming, the large-scale difference between Atlantic and Pacific ocean temperatures plays a fundamental role in causing droughts, and enhancing wildfire risks.

"Our results document that a combination of processes is at work. Through an ensemble modeling approach, we were able to show that without anthropogenic effects, the droughts in the southwestern United States would have been less severe," says co-author Axel Timmermann, Director of the newly founded IBS Center for Climate Physics, within the Institute for Basics Science (IBS), and Distinguished Professor at Pusan National University in South Korea. "By prescribing the effects of man-made climate change and observed global ocean temperatures, our model can reproduce the observed shifts in weather patterns and wildfire occurrences."



Read more at: https://phys.org/news/2017-07-atlanticpacific-ocean-temperature-difference-fuels.html#jCp