About 15 percent to 20 percent worse, according to a new study that is the first to put a number on climate change’s impact on the state’s dry spell.
Advertisement
California can blame about a fifth of the state’s record drought on climate change, scientists say.
Firefighters in California also are battling a fierce wildfire season that officials say has turned wilder and more unsafe because of bone-dry conditions from the drought.
The researchers analyzed monthly data on precipitation, temperature, humidity, wind and other factors from 1901 to 2014 and concluded that average temperatures in California climbed about 2.5 degrees Fahrenheit in that period.
Nevertheless, when rainfall declined in California in 2012, moisture evaporated at an unusually intense rate from soil, trees and crops, the study found. The findings suggest that within a few decades, continually increasing temperatures and resulting moisture losses will push California into even more persistent aridity.
“A lot of people think that the amount of rain that falls out the sky is the only thing that matters”, said lead author A. Park Williams, a bioclimatologist at Columbia University’s Lamont-Doherty Earth Observatory.
He explained further to Al Jazeera America: “Rising temperatures mean we have to get more rain just to break even. Each raindrop and each snowflake is a little less valuable”.
“Groundwater acts as a savings account to provide supplies during drought, but the NASA report shows the consequences of excessive withdrawals as we head into the fifth year of historic drought”, California Department of Water Resources Director Mark Cowin said.
Recommended: Climate change: Is your opinion informed by science?
“When this happens, the danger is that it will lull people into thinking that everything is now OK, back to normal”.
Moreover, while rain is expected to resume as early as this winter, “as time goes on, precipitation will be less able to make up for the intensified warmth”, Williams added.
“It used to be that half the years were warm, and half were cool”, Dr. Noah Diffenbaugh, the Stanford study’s lead author, told The New York Times. Now, aquifers are dropping fast, sending irrigation on a downward trajectory. Scientists call this process “positive feedback”.
The warming temperatures are making the drought worse because the extra heat draws moisture out of plants and soil, exacerbating the dryness, according to the study.
Advertisement
A new study has linked California’s drought conditions to man-made warming and quantified the extent of human contribution.
