California Snow Levels Below Normal Despite Heavy Rains

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climate scientist January 3, 2017, 4:57 pm EST

Today the California Department of Water Resources conducted its snow survey, which found below normal snow levels for this time of year.

In California, 2016 was the third hot year in a row—with some areas of the state experiencing temperatures up to 5 degrees hotter over this time period than normal. Temperatures remained high during an extremely soggy end to the year—in fact 2016 is expected to break global heat records.

This means that even while we received more rain than average over the last few months, we haven’t seen as much snow—a major source of California’s water. What’s more, higher temperatures caused by climate change could keep the Sierra snowpack low for the foreseeable future, according to a new study from UCLA and Oregon State University.

Rain levels above average, snowpack below average

Warming temperatures across California from 1/2/2014-1/1/2017, as compared to historical record. Data available at

If we look at the Northern Sierra, which drain into some of the state’s largest water supply reservoirs, rain levels are well above average (164% of average), but today’s snow survey found snowpack to be well below average at only 53% of average snow water content.

This is because most of the storms this winter have been warm, according to Doug Carlson, a spokesman with the state Department of Water Resources. Carlson points out that when so much water falls as rain, officials often must release some of it, as they have already been forced to do at Lake Folsom.

Climate change means California’s current water system is becoming obsolete.

Northern Sierra 8 Station Precipitation Index reflects a very wet fall. Data available at

As a consequence of the heavy rain in Northern California, many of the state’s reservoirs have re-filled (at least temporarily). Unfortunately, many of these reservoirs are only allowed to fill to about 80% of their capacity before they are required to release stored water in order to avoid dam failure or flooding. That means that early, heavy rains often cannot be effectively captured for later use.

If this strikes you as odd, that’s because it is—it’s just one more piece of evidence that climate change is already having profound impacts on California’s water supply. As temperatures rise, our state’s current systems for storing and moving water are quickly becoming obsolete. The public should demand a climate-resilient water system, but it is difficult when many don’t understand what’s at risk.

Take action: Help connect the dots on climate change

You can write a letter to the editor to your local paper ensuring they connect the dots on how climate change is contributing to California’s water woes.

In particular, media coverage tends to focus almost exclusively on short-term weather events like drought, El Niño, and La Niña rather than the much larger impact of climate change on our water resources. That’s why we call climate change “La Madre” of California’s water system.

Today, many local papers are reporting on the annual snow survey — submit a letter to your local paper that highlights the importance of climate change in their coverage, especially when it comes to our water needs.

Local newspapers are a go-to source of information for the public and decision makers alike, and their coverage influences how many of us think about California’s most pressing issues. By urging better, more responsible climate and water coverage, we can help build a more sustainable water future for our state.

Join us by sending a letter to the editor of your local paper or contacting your local television news station, asking for more thorough coverage of California’s water issues.

Posted in: Global Warming Tags: #tippingpoints

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