A wet winter won’t fix our drought

The National Oceanic and Atmospheric Administration along with other government agencies are predicting an El Niño/Southern Oscillation (ENSO) of possibly unprecedented strength for California over the winter of 2015/2016. In simple shorthand, that means that California as well as some of the Pacific Northwest and parts of Baja are going to get very, very wet. Heavy rainfall will likely be accompanied by high winds, mudslides, power outages, flooding, and other delights, potentially causing millions of dollars in damage as well as disruptions to business — flights in and out of California airports, for example, will experience heavy delays.

Rather than plunging into the nitty gritty of the science behind ENSO, it’s worth noting that the weather phenomenon isn’t just restricted to the Pacific Coast, as it actually has an effect on weather across the Pacific and the Americas. When it’s strong, it can cause substantial weather changes, including increased cold and heat, dryness or excess rain, changes in nutrients available in fisheries, and more. ENSO is a major weather phenomenon, which is one reason it’s heavily studied and researchers work so hard on predicting it and regularly updating forecasts.

While the internet jokingly develops a hashtag (#ElNinoOhNo? #ElNiNO? #Stormpocalypse2015?), it really is a serious issue, and many people don’t understand it very well. This includes people who are under the impression that El Niño is going to resolve California’s drought. This has already become a source of vexation, as every time it rains a few drops anywhere in California people triumphantly take to the internet to announce that hooray, the drought is over! We can all rest easy now, because it hath rained an eighth of an inch in Los Angeles. Or because monsoonal flow in Southern California has caused flooding, or there was a spat of hail in San Francisco.

For perspective, California has not seen drought conditions this bad in 500 years, and some research suggests that the last century actually reflected a period of unusual moisture across the state — California may be returning to equilibrium and its naturally more dry climate, which would be really bad news. The state’s water reserves are also heavily depleted. Images of the drought often show our nearly drained reservoirs, high water lines stretching above the current water level, and they imply that if we can just refill our reservoirs, everything will be fine. However, the real problem for California lies beneath the earth, where our underground reserves of water are rapidly shrinking as the state draws more water than aquifers can recharge. The problem is serious enough that subsidence is causing entire city blocks to collapse, especially in the Central Valley. It’s serious enough that it may take centuries for surface water to trickle back into aquifers and bring them up to previous levels.

That would require tremendous amounts of water over a sustained period of time. There is no way a single El Niño season could possibly address the state’s unprecedented drought, no matter how nice that would be. Even with substantial rainfall across the state, an increase in snow pack, and collection of water in depleted reservoirs, California will still be experiencing dry conditions and it will be struggling to produce crops as well as sustain its very large population. Neighbouring states also aren’t going to experience much drought relief — and California will continue to draw upon shared resources like the Colorado River, making their situation worse.

This isn’t just about the volume of rain California will receive, though the state would need 11 trillion gallons of rain — which is a lot, if you’re wondering — to recover from the drought. In the unlikely event that the laws of nature were completely upended, that rain would need to be meted out over time, just like offering someone with dehydration small sips of water rather than dumping a gallon down her throat. Have you ever overwatered plants? What happens when the soil can’t absorb water any more? It runs off. Which is precisely what happens during El Niño and heavy rainfall in California. Eventually, the ground becomes so saturated that it can’t hold any more water, and the water floods into waterways — often carrying nutrient-rich topsoil with it. I still remember the last El Niño of significance and the huge brown plumes of topsoil gushing out of the mouth of every river and straight into the ocean. Groundcover is torn away as well, increasing the rate of topsoil loss because there are no more roots to hold the soil down. Mudslides impede roadways and threaten houses, soil loosens around power poles and trees, causing them to call and generating millions in damages — and sustained periods in the dark.

El Niño jokes aside from a state that loves morbid humour about natural disasters, winter storms can and will have a huge effect on California in the coming months. High rainfall could be devastating, rather than a welcome thing, and it most certainly will not end the drought. Don’t let media foofarah fool you, and don’t be misled by confusing reporting on the drought and how it works. The state is, and will continue to be, in a state of ecological crisis and it needs to reform the way it uses water and other resources if it wants to prevent the disaster it is rapidly facing down.

Image: Singin’ in the rain, streetwrk.com, Flickr