Why 'the Worst of Both Worlds' Is in the Forecast

The good news for residents of Northern California — which has been battered this week by historic rain and flooding that has been blamed for at least one death — is that the worst is most likely over.

The swollen Russian River, which essentially turned the town of Guerneville into an island, is forecast to recede in the next day or two, returning to below flooding levels by early Friday morning, said Scott Rowe, a National Weather Service meteorologist.

Gov. Gavin Newsom declared a state of emergency Thursday in five hard-hit Northern California counties, which aims to help communities recover.

The bad news is that these kinds of severe storms are likely to get more frequent, as climate change contributes to what experts say will be a future marked less by gradual, steady warming than by a kind of weather whiplash.

That’s how Daniel Swain described it. He’s the California Climate Fellow for the Nature Conservancy, a researcher, and the expert behind the Weather West blog.

Swain was initially asked about wildfires — their increasing severity and frequency — but, he explained, fire and rain and floods are part of climate cycles that are becoming more extreme.

“The average condition doesn’t characterize what you experience,” he said. Average temperatures are rising, he said, and what’s starting to become clear is that “the impacts of those warming temperatures are not incremental in living systems.”

An average over years doesn’t capture the real effects of a devastating drought and wildfires followed closely by a particularly wet rainy season on environments and communities, which are increasingly being built into wilderness areas. As a result, Swain said, Californians end up dealing with “the worst of both worlds.”

The question then becomes: How do you manage land use to minimize harm from extreme weather? Is it possible to store water when it rains and save it for when the state is wracked with drought?

It would be simple to, say, return it all to its natural state. Rip out the concrete in the Los Angeles River, let wildfires burn what they will, never allow construction where there’s any risk of disaster.

But Swain said it’s impossible to ignore the presence of humans or to discount the value of communities that have already been built — even if they coexist with the environment imperfectly. Going forward, he said, there are opportunities to build more sustainably, and for policymakers to think carefully about managing things like groundwater.

For now, though, Rowe, of the National Weather Service, said that another storm could be heading toward the Central Coast next week.

This article originally appeared in The New York Times.