In a report by Phys.org, they shared that the 20-year dry spell currently being experienced by much of the western United States is not a natural occurrence, but a result of human-made global warming. The report focused on a study from the journal Science released on April 17.
A new study says the 20-Year megadrought in the Western US is caused by man-made global warming
According to the report, the study observed a nine-state area from Oregon and Wyoming down to California and New Mexico.
The methodology involved looking at tree rings--cross-sections of trees--to compare the drought that started at the turn of the millennium in 2000 that has continued to this year. It's been called "one of the deepest megadroughts in the region in more than 1,200 years."
According to the study's lead author, A. Park Williams, who is also a bioclimatologist at Columbia University, the phenomenon that is happening right now in the Western US is "a drought bigger than what modern society has seen."
Is it really because of human-made global warming?
According to the report, to determine the exact role of human-made global warming in the observed phenomenon, researchers used computer models to compare two different situations.
They looked at what was happening now and then looked at a hypothetical situation without the burning of fossil fuels that release billions of tons of gases that trap heat--an activity that is exclusively performed by humans. And they discovered that on average, "47% of the drought could be blamed on human-caused climate change."
According to Williams, "We've been increasingly drifting into a world that's getting dryer."
In another related Phys.org report, Williams was quoted saying that "earlier studies were largely model projections of the future."
"We're no longer looking at projections, but at where we are now," he added.