California's Changing Weather Patterns Will Impact San Diego's Water Retention

From years of drought to intense storms dumping buckets of rain in a short amount of time: New research revealed Tuesday says changes in California's weather are about to make it the Wild West.

The author of the study, a researcher at the Scripps Institution of Oceanography in La Jolla, says there are two words San Diegans need to know when it comes to climate change locally: "Atmospheric Rivers"

"The dry periods get longer but then when the rain comes it will tend to be more intense,” Research Meteorologist Alexander Gershunov says.

Gershunov has devoted the past few years of his career to the study of atmospheric rivers, which are basically exactly what they sound like -- rivers of water in the sky.

The tropical moisture moving north into California gets squeezed out by our mountains resulting in heavy rainfall in sporadic, short amounts of time.

Gershunov says a warming climate only makes these rivers stronger, which brings along greater chance of flooding, mudslides, erosion and spikes in poor water quality around the coast.

At the same time, Gershunov says the frequency of cold fronts are decreasing -- which means less snow pack -- making more and more of our rainfall totals dependent on atmospheric rivers.

According to his models, the yearly rainfall totals in San Diego may not change much over the decades to come. It's just the rain will come down all at once.

Gershunov says understanding these changes and what's behind them is critical for water resource decision makers who will have to manage reservoirs built for collecting snow melt.

“If more of it comes off the mountains as it's falling from these warmer storms in the winter time, you can't really keep a full reservoir, you have to make room for the next storm,” he said.

As a result, he says water managers in the future will have to rely even more heavily on weather forecasts.

The report was published Tuesday in the scientific journal "Nature.Com."

While 2019 has been a year of heavy snow fall so far, Gershanov says this will be rare in the decades to come.