El Niño Slightly Improved The Drought But Didn't Bust It
Here's what we've learned from the KPBS Drought Tracker
I'm Maureen Cavanaugh, climate experts told us that this year's El Niño would not end California's multiyear drought. It looks as though they were about. The last big El Niño, back in 1998, left California with snowpacks and rainfall totals about 160% of normal. This year the rainfall is just about average and the snowpack is under 100%. Science reporter David Wagner brings us an update. For the past few months we have been tracking statewide rain and Sierra snow to give you a better sense of how El Niño is affecting California's drought. We have limited our focus to California's wettest months which stretch from the beginning of October to the beginning of April. California is traditionally defined wet season is over. When we what -- launched the KPBS Drought Tracker , we want to see 156 -- 150% normal by April 1. We only got average precipitation. Rainfall topped out at 108% of normal. The Sierra snowpack was just below normal at 91%. Where do those numbers leave us today? Has the drought gotten any better? To find out I went to the Scripps Institution of Oceanography to ask the researchers . In broad measure, I would say we've gotten better. Not so much better that we can say we of God to pre-drought water condition level says climate researcher, Dan Cayan. He says El Niño has filled some reservoirs, but precipitation was not evenly distributed. In this case, the West Coast distribution, wet in the north, dry in the South, was pretty much topsy-turvy of what we expected. This winter's strong El Niño pattern is starting to break down and the National Weather Service's climate prediction Center says there is a 50% chance that it could give way to a La Niña pattern by fall. La Niña is when it's unusually cool at the tropical Pacific surface. David Pierce is another researcher. La Niña has an impact on the US because it's associated with dry conditions. If we are headed for a strong La Niña, California could be in for another year of drought. Pierce has seen some signs of a budding pattern, but says it's still too soon to predict. The majority of the models are showing we might go to La Niña, in my opinion, it's too far out. What we do know, is that current snow levels will not pull us out of the drought. This year a snowpack, never quite got to 100% of normal this wet season. Dan Cayan says that's in part because temperatures in California were relatively high at various points . That makes for rain instead of snow and it tends to melt snowpack a bit earlier. This winter wasn't quite as warm as past winters. It was warm enough to affect snowpack growth. Dan Cayan says this could be a preview of global warming. He showed me a model estimating that for every degree of selling CS, -- Celsius California could lose snowpack. Less snowpack will mean less water stored for spring and summer. It will be a different form of water management. What have we learned from the KPBS Drought Tracker? We have learned it's hard to predict how El Niño will impact California. Even strong El Niño's don't bring above average rain falls. Despite big improvements, the drought is far from over. To see the final numbers go to KPBS.com/drought. Tran eight is with me. As a water manager, were you hoping for more precipitation? Yes, absolutely. Forecasters had put Dick did a really strong El Niño. We were above average in Northern and Southern California. We were disappointed. How would you categories the water supply? I want to point out, right now, we only get 10% of our water from service water, the local rainfall. We have very little, that are reliant on the local weather. Since the early 1990s, we have been investing in what we call drought resilient supplies, these are conserved water transfers from the Colorado River where the farmers in the Valley conserve water. Water recycling projects are built throughout the region, we are in a good position, even though we are going into another dry year, because of these investments. We also have the sand the Cente damn -- Sandra Cente. Again we've got 80,000 acre-feet of water stored in that reservoir, we are going into this in a good position Our reservoirs are at capacity? They are at 40% capacity. We did not see above average rainfall. On average, that's only about 10% of our supply, even in their -- a strong El Niño. Statewide, Californians came close to meeting that 25 predict -- reduction in water. Now there is a debate as to whether to change those goals. What is San Diego's target right now? Is it different in each miss the polity? The state water resources control Board established measures. We aggregated those and came up with a regional target which was 20%. I am happy to report that here in San Diego County we did reach that goal. We were at 21% cumulatively, since June 2015. It is, between 8% and 28%, it's important to contact your local region. What would you like to see conversation -- conservation goals be, would you like to see them reduced? We always know, it's so important that we use water efficiently. One thing we have advocated is any shortage has to be related to the actual supplies you have available. It can't be an arbitrary number that, look at your supply and demand, that's what establishes your cut back level. Not an arbitrary level that comes from the state. What you think our cutbacks should be? Having water in carryover storage, I think we can meet all of our demands coming into this year. So you don't think we issued have a conversation -- conservation goal? Yes, all the time. This should be a decision of the local policymakers. We don't know if we were going to go into a fifth or sixth year of drought. We may still have some level of conservation cut back, where people are saving. We are always advocating for people using water efficiently. The Metropolitan water District is expected to vote on a rate hike for San Diego. They will use the same calculations that were ruled unfair and were struck down by a judge in a lawsuit that San Diego one last year. That case is being appealed. What is the authority going to do about those expected rate hikes? I think we will, obviously our position is clear, we will continue down that same path. Of fighting back against what these Ray kites, that you have deemed to be and you feel are unfair. Yes. Absolutely. The voice ran a story about the diversion of treated water into a lake near Chula Vista. How was the water authority working to fix that? We still are coordinating with the Metropolitan water District on that. We have requested reduction in flows, treated water flows. We are coordinating with them on that to remedy this issue. It's a complicated situation. Yes. I've been speaking with tran eight, Water Resources Manager with San Diego County Water Authority. You are listening to KPBS, midday edition.
For the past few months, we've used the KPBS Drought Tracker to tell you how much rain and snow El Niño has been bringing to California. Now that we've reached the end of what turned out to be a fairly average wet season, where does California's drought stand now?
We've limited our focus to California’s wettest months, which stretch from October to the beginning of April. We could still see some rain in coming weeks, but California’s traditionally defined wet season is now over.
When we launched the KPBS Drought Tracker, climate experts told us rain and snow levels would have to reach 150 percent of normal by April 1 to really put a dent in the drought. This year's numbers didn't come close, but they were an improvement over all previous years in California's prolonged drought.
Last year, Sierra snowpack hit a record low on April 1, measuring just 6 percent of its normal level. This year's measurement was just below normal at 91 percent. Statewide rainfall was also higher than in previous years, topping out at 108 percent of normal by April 1.
But this year's numbers were nowhere near as high as those seen in 1998, toward the end of the last major El Niño. California received 164 percent of its normal rainfall that year, and 166 percent of its typical snowpack.
So where do today's numbers leave us? Has the drought gotten any better?
To find out, we asked the Scripps Institution of Oceanography climate researchers who helped compile data for the KBPS Drought Tracker.
"In very broad measure, I’d say we’ve gotten a little better,” said Scripps climate researcher Dan Cayan.
But not so much better we can safely go back to pre-drought water consumption.
Cayan said El Niño rains filled some major reservoirs in Northern California. But precipitation was not evenly distributed throughout the state, leaving other areas fairly dry.
"In this case, the West Coast distribution of precipitation — wet in the north, dry in the south — was pretty much topsy-turvy of what we expected,” Cayan said.
The U.S. Drought Monitor shows that about 75 percent of California remains in "severe" drought or worse.
Cayan said continued conservation would be prudent, because we don’t yet know what’s in store for California’s next wet season.
This winter’s strong El Niño pattern is starting to break down, and the National Weather Service’s Climate Prediction Center says there’s a 50 percent chance it could give way to a La Niña pattern by fall.
David Pierce, another Scripps climate researcher who helped with the KPBS Drought Tracker, explained, “An El Niño is when it’s unusually warm in the tropical Pacific Ocean. And a La Niña is when it’s unusually cool at the tropical Pacific surface."
If we are in for a strong La Niña, California could be headed for another year of drought. That's because La Niña "is associated with dry conditions," Pierce said.
He has seen some evidence of a budding La Niña pattern in the Pacific. But he says it’s still too soon to predict whether it will set in.
"Right now, a majority of the models are showing we might go to La Niña conditions. I personally think it’s pretty far out to say that with any certainty," Pierce said.
What we do know about the next few months is that current snow levels won't pull us out of the drought.
The Sierra snowpack, which provides about a third of California’s total water supply, never quite got to 100 percent of normal this wet season.
Cayan said that’s in part because at various points this winter, temperatures were relatively high in California.
“And, of course, that makes for rain instead of snow and tends to melt snowpack a bit earlier,” he said.
This winter wasn't as warm as past winters in the drought. But it was warm enough to affect snowpack growth. Cayan said this could be a preview of how global warming will affect the Sierra snowpack in the future.
He has a model showing that for every degree of Celsius in warming, California will lose about 20 percent of its April 1 snowpack.
“By the end of the century, you can see here, in this particular example, we’ve lost more than half of the snowpack," Cayan said.
Less snowpack will mean less water stored up for spring and summer. He said climate change is going to shift our understanding of normal for this crucial water source.
“It’s going to be a different form of water management that we’re confronted with,” Cayan said.
So, what have we learned from the KPBS Drought Tracker?
We’ve learned that it’s hard to predict how exactly El Niño will impact California. Even strong El Niños don’t necessarily bring record rain and snow to the state.
And we’ve learned that despite big improvements over recent years, the drought is far from over.