Opinion | California’s Drought Is Worse Than We Thought


Outside my lab near Donner Pass in California’s Sierra Nevada mountains, there are new animal tracks in the snow after hibernation, bird sounds in the air, and the creek rushes strong with water from the melting snow. Spring has come alarmingly early in the Sierra Nevada.

Last week, I joined teams of other scientists from around the world collecting the most important measurements of the Sierra Nevada snowpack. 265 sites across the state. Typically, this measurement marks the transition from snow accumulation season to melt season and contains the most snow of any measurement during the year. But the 2022 results confirmed what those who watched the state’s drought feared: California’s snowpack is now 39 percent lower than its average, or 23 percent lower than the same point last year. This signals the deepening of the drought – already Worst in 1200 years in the western United States — and another potentially disastrous fire season for much of the West.

Many people view drought quite simply as a lack of rain and snow. That’s right – to some extent. What it doesn’t calculate is human activities and climate change that are significantly affecting available water and its management. As more frequent and massive wildfires and long dry periods ravage land, our most important tools for managing water are becoming less and less accurate. At the same time, it’s becoming more and more problematic that we rely on these models to try to make the most of the little water we have.

Droughts can last for several years or even more than a decade, with varying degrees of severity. During such prolonged droughts, the soil can become so dry that it absorbs all new water, reducing the flow into streams and reservoirs. The soil can also be so dry that the surface hardens and repels water, this can cause rainwater to spill rapidly from the land and cause flooding. This means that we can no longer rely on relatively short periods of rain or snow to fully relieve drought conditions as we did in past droughts.

Many storms with record-breaking amounts of rain or snow would be required in a single year to make a significant dent in drought conditions. October was the snowiest month recorded in the snow lab since 1970, thanks to two atmospheric rivers hitting California. However, the extremely dry November and January-March periods left us behind for another year with below-average snowpack, rain and flow conditions.

Such feast or famine winter with great storms and long, severe dry periods Expected to increase as climate change continues. As a result, we’ll need multiple above-average years of rain and snow to make up the difference, rather than consecutive major events in a single year.

Even in years with normal or above-average rainfall, changes in land surface present another complication. Massive wildfires, such as we’ve seen in the Sierra Nevada and the Rocky Mountains in recent years, are causing marked changes in the melting of snow and the way water flows through land, including rain. this forest canopy loss from fires can result in higher wind speeds and temperatures, which increase evaporation and reduce the amount of snow water reaching the reservoirs.

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Similar to prolonged drought, fire also changes soil properties and can create flash floods during periods of heavy rain. These landscape changes, festive or famine rainfall patterns, and increased water demand make water management a dangerous and difficult task in the West.

One of the most important tools for managing water during times of drought are models developed by various state and federal agencies, such as the National Weather Service Office of Hydrological Development, the Army Corps of Engineers, and the California Department of Water Resources. Yet these models suffer from the same simple vision of drought and water and need a serious update.

Land surfaces, snowmelt patterns and climate have changed since many of these models were developed, meaning they’re missing important pieces of today’s water puzzle. What has prevented models from being updated for decades is declining funding for science and engineering.

Models may not be able to reliably inform water managers how much rain and snow from the land will flow into reservoirs, which in the worst-case scenario could mean severe shortages. Given the declining reservoir levels and inadequate snowpacks in recent years, discrepancies between expected water and incoming water could mean the difference between water drying out at the taps or in entire towns.

In the west we are looking at the barrel of a gun filled with our water sources. Instead of investing in body armor, we were hoping the trigger wouldn’t be pulled. Current water monitoring and modeling strategies are not sufficient to support the increasing number of people in need of water. I worry about the next week, month, year, and the new challenges we will inevitably face as climate change continues and water becomes more unpredictable.

It’s time for policy makers allocating funds to invest in updating our water models rather than maintaining the status quo and hoping for the best. Large-scale investments in institutions that maintain and develop these models are crucial to preparing for the future of water in the West.

Better water models ultimately mean more accurate management of water, which will ensure greater water security and availability for the millions of people who depend on changing water resources. It is an investment in our future, and also an ongoing investment in our ability to live in water-scarce regions of the West. It’s the only way to make sure we’re prepared when the trigger is pulled.

Dr. Schwartz is chief scientist and station administrator at the Central Sierra Snow Lab at the University of California, Berkeley.

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