In all, nearly 85% of the West is experiencing drought conditions right now, according to the US Drought Monitor. Nearly half of the region is now in severe or exceptional drought, after years of dry and hot conditions exacerbated by climate change.
The direct cause of this year’s drought is the weak summer monsoons, coupled with La Niña conditions that directed storms northward. But the problem goes far beyond the drop in precipitation and snow in recent months. The Southwest has suffered through a drought since the 15th century for now two decades, according to Study in the sciences last year.
Climate change accounts for 46% of its severity, driving what would have been a mild drought in the ‘mega-drought’ region. Several other studies have found that higher temperatures mean “more frequent and severe droughts in the southwest,” Indicated National Climate Assessment 2018.
“The snow is melting faster. There is more evaporation.” “It just changes the game in so many different ways,” says Nisha Ajami, director of urban water policy at the Stanford Water Initiative in the West.
Regions are already scrambling to confront the growing dangers.
In California, Governor Gavin Newsom Had suggested Spending more than $ 5 billion to meet emergency water needs and support regional water infrastructure, among other efforts. he is too Drought emergencies declared Across 41 counties, it covers nearly all of Northern California and the Central Valley, the state’s rich agricultural region.
In Marin, a northern San Francisco county largely cut off from regional water systems, reservoirs are depressing ominously after rainfall nearly dipped this year. Water area discusses possibility Build a temporary pipeline at least He crossed the Richmond-San Rafael Bridge to ensure water supplies, for the first time since the state’s crippling drought of 1976-1977.
Researchers, officials, and emergency responders are also preparing for another terrible fire season, which is starting early. The Palisades fire burns near Los Angeles Over 1000 acres In recent days, more than 1,000 people have been forced to flee their homes.
“Some elements of the fire season risk are predictable;” some are not, “says Daniel Swain, a climate scientist at the University of California, Los Angeles, who focuses on weather conditions that cause droughts, floods and wildfires. . “
The new normal
Some climate modeling finds this Warming increases contrast Of precipitation patterns, resulting in what researchers studying California conditions describe as:injury“Between periods of severe drought and floods.
But the extreme periods of years do not naturally balance with each other, even if average precipitation levels remain the same. If regions do not fundamentally rethink how they manage water, it often means simply switching from one type of disaster to another (see the 2012-2016 drought in California, which was immediately followed by years of floods that caused mudslides and road sweeping. One dam Near the breaking point).
“We have to shift our thinking to ‘drought is a natural thing,’” says Ajami. “And then when we have wet years, we should get excited and do a billion things to capture as much water as possible, to ensure we store enough when we dry up again.”
This will require better utilization of groundwater by cleaning up polluted aquifers and replenishing them during years of torrential rains. Areas will also need more efficient use of water once it is introduced into the system, minimizing, reusing and recycling it wherever possible.