In the last decade, California weather has become synonymous with drought — and nearly a year ago, officials say drought conditions were only getting worse. Indeed, in 2022 California experienced its driest January, February, and March in over 100 years, following a fortuitously wet December.
One year later, the situation couldn't be more different. The year 2023 began with a series of "atmospheric river" storms which, alone, were already historic. In February, typically when spring looms in California, rare low-level snow hit areas like the San Francisco Bay Area and Los Angeles County as another series of massive storms passed through the state.
Despite the heavy rainfall across the state and blizzards pushing snowpacks to double a normal season's levels, officials have been adamant that the state is still largely in a drought, perplexing boot-muddied Californians. As each storm passed, the heavy rainfall frustratingly did little to alter the drought monitor map that is assembled weekly by the National Drought Mitigation Center at the University of Nebraska, Lincoln and the National Oceanic and Atmospheric Administration (NOAA). On March 2, the monitor's weekly update showed that only half of California is no longer classified as being in drought. Still, many of those areas are still categorized as "abnormally dry."
"Obviously, it looks much better than it looked two months ago, but I always caution people to use that [the drought monitor] as the only indicator of where we are in the drought because when we go through a severe drought, we start doing a lot of different things that can impact our ecosystem," Newsha Ajami, a water expert at the Lawrence Berkeley National Laboratory (LBNL), told Salon.
Ajami said that the extreme drought in California has pushed the state to extract water from groundwater basins. "All of a sudden, you have a big deficit that you need to fill and the drought monitor doesn't necessarily cover that."
In order for the entire state to be drought-free, Ajami said the state would need three to four years of storms like it had this year — all in a row.
One consequence of this is that salmon runs are low in California as moving water from some reservoirs have restricted the flows for endangered salmon.
Climate scientist Alan Rhoades told Salon that the precipitation the state experienced this year was "unexpected," in part because it is the third year of La Nina. Historically, that means winters will be cold and dry.
"This was a really pleasant surprise water year," Rhoades said.
Echoing Ajami, Rhoades rued that it's been difficult to catch up because of the damage that's been done over the last several years.
"It's the bank account analogy — that we've been taking from our savings for so long that you need to recoup those finances," meaning water, Rhoades said. "We need more time to get the soil moisture back to kind of where it was, the groundwater tables, the vegetation and trees need time to regenerate."
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In order for the entire state to be drought-free, Ajami said the state would need three to four years of storms like it had this year — all in a row. The state would also have to recharge the groundwater basins, so some of the species who have been affected could be restored to healthier populations. Among the last ten years, only 2017 and 2019 have been notably wet, while the remaining years were defined as drought years. The rarity of a wet year affects the potential of recovery.
"We need more time to get the soil moisture back to kind of where it was, the groundwater tables, the vegetation and trees need time to regenerate."
Ajami said those two wet years have perhaps put a dent in the drought situation, but "not necessarily eliminated it."
"It takes a while to recover from those 10 years and be able to recharge," Ajami said. "And because of those 10 years, a lot of water utilities are sort of hesitant (when they get water) to do anything — they want to make sure they store as much as they can, because they don't know what's going to happen next."
While climate experts like Ajami and Rhoades welcome the news that only half the state is now in drought, other experts are more wary of making hopeful prophecies.
As climate scientist Michael Wehner, who also works at the Berkeley Lab, told Salon: "Drought is complicated." He says this is partly because there are different definitions of a drought, and the effects of each are intertwined. According to NOAA, they are meteorological drought, hydrological drought, agricultural drought, and socioeconomic drought. Meteorological drought happens when there are dry weather patterns in an area; hydrological drought is when low water levels are evident after many months of dry weather. Agricultural drought is when crops are affected by the dry weather, and socioeconomic is when the supply and demand of crops are being affected by the former.
The climate experts said that the future of the state's drought status also hinges on what happens next.
"It's been a big snow year and that snow is going to melt, but there are some concerns about that melting really fast," Wehner said, adding that the possibility of an extreme heatwave is worrisome. Just as the types of droughts are connected and affect the state's drought status and severity, what happens next with precipitation will affect how California recovers from the drought.
"If we have an early heatwave, and the snow is melting too fast, then the water management system will have to deal with it — and that may mean letting a lot of water go early," Wehner said. "Also there's the issue of slides and mudslides."
Ajami said she is hoping that a heatwave doesn't immediately follow in the next few weeks, too., because if temperatures are too high, snow will evaporate instead of flow into rivers and reservoirs.
"We are having the wet years and dry years, and then within each year we also have this internal variability, which we call whiplash," Ajami said. that you go from this to major storms that dump lots of snow and rain and then all of a sudden, "It's very unpredictable."
Rhoades said California is going to have to "wait and see" how the snow melts, and what the impact of that will be on drought conditions.