Boston, MA, January 26, 2021 – Precipitation from Hurricane Dorian, South Africa’s extraordinary four-year drought, fires in Alaska and China, and devastating flooding in southern Canada were some of the extreme weather events made more likely in 2019 by man-made climate change new research published today in the Bulletin of the American Meteorological Society (BAMS).
The 10th edition of the report, which explains extreme events in 2019 from a climatic point of view, contains 17 new, peer-reviewed analyzes of extreme weather on five continents and one sea in 2019. The research of 80 scientists from seven countries addresses two historical subjects, observations and model simulations, to determine whether and to what extent climate change has influenced certain extreme events.
“The attribution studies published in BAMS show how cleverly these questions can be answered,” said Keith Seitter, Executive Director of AMS. “Being able to determine the extent to which a particular event has been altered by climate change is an important part of increasing the public’s understanding of the very real impact our climate change has on them.”
Stephanie Herring, NOAA climate researcher and editor of Explaining Extreme Events, said that as the field of climate mapping matures, so too will the scientific tools available to identify a climate signal during extreme weather events.
“This year we are also seeing increasing evidence of our ability to identify a signal of climate change in various types of extreme weather events, particularly forest fires and rainfall,” said Herring. “We also keep seeing results that suggest that extremely cold weather is becoming less likely due to man-made climate change.”
In this issue, some results from studies on extreme weather in 2019 were published.
- Climate change increased the risk of extreme heat from March to June 2019 in the Chinese province of Yunan by 123 to 157 percent and the likelihood of the accompanying drought by 12 to 23 percent.
- Climate change has made extremely warm winter days in Central England 300 times more likely in winter 2018-2019.
- The 2019 northwest Pacific marine heat wave has been amplified by a multidecadal natural ocean cycle that is likely to worsen due to the effects of climate change.
- Major cold outbreaks in the eastern US in November 2019 were 70 percent less likely due to climate change.
- Two model studies suggest that the extreme spring cold in spring 2019 on the Tibetan plateau was 80 percent lower due to climate change.
Heavy rainfall and flooding
- The month-long flood over Ontario and Quebec that contributed to the Ottowa River flooding in 2019 is now two to three times more likely due to climate change.
- Climate change slightly increased the likelihood that Hurricane Dorian was seeing extreme 3 hour and total amounts of precipitation.
- Climate change has made the high Susquehenna River, which flows into Cheseapeake Bay in 2019, more likely in the future.
- Due to climate change, the heavy rains observed in southern China from March to July 2019 were 60 percent less likely than in the 1960s.
- The extensive winter rains from 2018 to 2019 over the middle and lower reaches of the Chinese Yangtze were 19 percent less likely due to climate change.
- Analysis of the record number of typhoons in Korea in September 2019 revealed no discernible impact of climate change.
- Climate change doubled the likelihood of prolonged drought from 2015 to 2019 in the Western Cape region of Africa.
- Climate change increased the likelihood of an extreme drought in southwest China, as seen in 2019, by a factor of 6, based on a model study.
- A retrospective study showed that major Alaskan wildfires, such as the one-third larger than the state of Rhode Island in Alaska’s warmest July in 2019, were three times more likely in the past few decades due to man-made ignitions. Extremely hot and dry conditions caused by climate change supported the unusually early and strong peak of the 2019 fire season.
- The weather-related risk of extreme forest fires in southern China in 2019 was increased by 7.2 percent due to climate change. The El Nino increased this risk by a further 3.6 percent.
The extreme weather events examined in the ten annual editions of the report were selected by individual researchers and do not constitute a comprehensive analysis of events during that period. Approximately 75 percent of the 185 research published in this series identified a significant link between an extreme event and climate change. about 25 percent don’t.
DOWNLOAD THE FULL EXTREME EVENT REPORT: https://www.ametsoc.net/eee/2019/EEEin2019.pdf