California's Record Rainfall Won't End the State's Mega-Drought — Here's Why

California's Record Rainfall Won't End the State's Mega-Drought — Here's Why
Source: AP
Source: AP

California was smacked by a splash of hope Saturday and Sunday when Tropical Cyclone Dolores opened the skies, sending record-shattering rainfall upon the drought-stricken state. For a moment, it almost seemed like a sign of watery salvation for a state dealing with a historic drought

However, the superstorm left a disastrous path through parts of the region, wiping out power for over 10,000 homes and blanketing parts of the state in flash flooding. In fact, in the deserts of California, an entire bridge on Interstate 10 was swept away by the floods, leaving the highway shut down "completely and indefinitely," Terri Kasinga of the California Department of Transportation told the Associated Press.

Parts of California's Interstate 10 were washed away Saturday and Sunday by Tropical Cyclone Dolores.
Source: Chief Geoff Pemberton/AP

But what's more, while the much-needed rainfall brought moisture to areas that haven't felt it in months, it's done nearly nothing to rid the state of a drought that's forced water rationing and given a poor agricultural outlook.

"The rainfall in [California] over the weekend, while it did break July precipitation records in some places, will not do much to pull California from the ongoing 4-year drought event," Park Williams, assistant research professor at the Earth Institute at Columbia University, told Mic. 

In fact, though some places will surely benefit from the new moisture, Williams said, ironically enough, "the desert portion of [California] that received much of the anomalous precipitation in this event is the area that needs drought relief the least."

Even the rain that did fall on the right areas won't have much of an effect. According to Williams, summer precipitation is actually much less helpful in combating the drought because it evaporates much more quickly in the warmer temperatures, meaning "a summer rain drop is, on average, less effective at actually producing drought relief than a winter rain drop."

While this weekend's downpour was a record-breaking event, what actually will actually soak into the ground as a form of drought relief is not all that high, "so the ultimate effect on California's current water deficit, which is over one whole winter's worth of precipitation, will be near zero," Williams told Mic.

In fact, the cyclone probably did more harm than good to the region with crippling floods and compromised freeways. Weather.com reports the situation developing in California is become ever more interesting, in a case that has meteorologists scratching their heads and researchers unsure of what to do next.

Meterologist Nick Wiltgen tells Weather.com,

"This is a fascinating situation on so many levels. Against a backdrop of climate change, with the global atmosphere setting heat records month after month, we have an El Niño warming the waters of the tropical eastern Pacific. On top of that, the waters off the U.S. West Coast are also far warmer than average, and we have a tropical storm moving farther north and closer to the Mexican coast than most others in the historical record this early in the season."

One potential upside is that Tropical Cyclone Dolores increased the likeliness of more rainfall to come in the following weeks, but researchers say they are waiting to determine the superstorm's full effect on California and the drought that has gone on with no end in sight for years.