Why a "Godzilla" El Niño won't end California's drought


Mudslides in California during the 1998 El Niño.

David Gatley/FEMA

An El Niño advisory is now official, and scientists suggest there is a greater than a 90-percent chance that it will arrive this winter.

They also believe the developing El Niño could become one of the most powerful on record – rivaling its 1997-98 predecessor, which sent California twice as much rain and the Sierra Nevada double the snowpack it usually gets.

So the news of another El Niño probably sounds like a blessing for thirsty California, the world’s eighth largest economy, as it suffers through its worst drought in more than a millennium.

Unfortunately, the impending weather phenomenon won’t reverse the drought and – and here’s why. 

  • There is a strong chance the rain won’t show. The 1997-98 Western storms may be fresh in mind, but with conditions similar to what we’re seeing this year, California as a state may, in fact, be getting less rain than it normally does. Historically, this has been true with nearly half of such El Niños. And even if Southern California gets above-average rainfall, as it often has in the past, that would do little to fill the state’s northern reservoirs.
  • Too much rain at once can be problematic. The ground can’t absorb massive rainfall quick enough, so most of the rain washes into streams and rivers – and eventually the ocean – instead of replenishing the groundwater table. The lack of absorption also means more flooding, mudslides and other emergencies.
  • Years of drought can’t be erased by a single, wet season. Drought is a water-balance issue, and the deficit in water has been piling up for four years. It is unlikely that a season or two of more rainfall than usual will make up the difference.
  • El Niño will bring along record heat. This will exacerbate drought conditions and lead to less snow in the mountains, which perpetuates to the cycle of drought.

Adding to California’s growing list of woes, there are other ways El Niño that could be disastrous.

Part of a naturally occurring, irregular ocean-atmosphere climate cycle, El Niños are responsible for all sorts of global weather events, some of which are beneficial and many that are harmful.

The 1997-98 El Niño caused 35 counties in California to be declared disaster areas. Mudslides killed 17 people that season and there were $500 million in damages. Worldwide, more than 20,000 people were killed.

Understandably, California is now preparing for what may become a destructive “Godzilla” El Niño winter – rather than welcoming much-needed rain.

So what will it take to end the drought and get California back in balance?

We need Mother Nature to shift some meteorological and oceanic conditions that we have no control over, but there’s more to the equation. Climate change may be playing a significant role in the drought by altering the jet stream through warming in the Arctic.

And for that, we do have a plan.

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Ilissa Ocko

Ilissa Ocko

A scientist who explains climate change for a lay person.

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If you focus on being more negative, more people will care about you.

Seems to me that I've seen droughts and wet weather on and off from my 70 years in California.

The points in this article are based on a fundamental misunderstanding of California's water situation. One year of heavy rainfall can make a huge difference. Refilling our reservoirs is the first priority and that will happen with the big El Niño.

Thank you for the story. I believe that the expectations of El Nino may be causing an air of complacency that may postpone other immediate measures from being pursued. "California's Passing," which I wrote, is a song about the possible effects from the drought in the not too distant future. I am also in the process of finishing a novel titled "Closed" about California in the year 2018. The title tells it all.
Thank you again for a sobering report.
Thomas Hills

I am 100% for reducing our climate footprint to the greatest feasible extent but, as a resident of Southern California, I'm really tired of people telling me that one wet winter will not signal the end our drought. Of course it won't. But...it would be a whole lot better than another dry winter.

Then again, if we somehow have five or six consecutive years of above average rainfall you could look back on the El Nino of 2015 and say that it WAS the end of the drought. We just don't know what the future holds.