A UCLA study shows that abnormally heavy rain and snowfall events since as early as the 1980s are intensifying globally due to human-driven climate change.
“These findings further elevate the urgency of reducing greenhouse gas emissions to prevent even larger impacts down the road,’’ said senior author Alex Hall, director of the UCLA Center for Climate Science, which is a part of the UCLA Institute of the Environment and Sustainability.
“We can now say that extreme precipitation is increasing globally due to human-induced climate change.’’
The study was published Tuesday in Nature Communications, and shows the human influence in issues like floods, soil erosion, crop damage and problems with water resource management.
For more than a decade, climate models used in previous studies had already predicted that human-induced climate change would lead to more intense extreme precipitation events, but struggled to show it in historic precipitation records. Employing new methods, the UCLA research team found the evidence.
They used new machine learning methodology to compare 11 global land precipitation records from 1982 to 2015, and found an identifiable anthropogenic signal in 100 percent of the historic records, according to Gavin Madakumbura, the study’s lead author and a UCLA doctoral candidate studying climate modeling.
“This is the first time anyone has taken into account these deep uncertainties to detect a human influence on extreme precipitation over the whole globe,’’ Hall said.
Madakumbura added that change in climate may be traced as far back as 200 years.
“We know that the signs of human influence started in the Industrial Revolution in the 18th century, but it takes some time for the signal to be strong enough to recognize compared to natural variations,’’ Madakumbura said. “We used this new methodology to build on the work that came before, and it means we can look at these disparate datasets from different regions around the world and still detect the human influence.’’