Climate change has California planting some trees
MODESTO, Calif. — For years, there has been a movement in California to restore floodplains, by moving levees back from rivers and planting trees, shrubs and grasses in the low-lying land between. The goal has been to go back in time, to bring back some of the habitat for birds, animals and fish that existed before the state was developed.
But in addition to re-creating the past, floodplain restoration is increasingly seen as a way of coping with the future — one of human-induced climate change. The reclaimed lands will flood more readily, and that will help protect cities and towns from the more frequent and larger inundations that scientists say are likely as California continues to warm.
“We thought we were just going to plant some trees out here and get some birds to move in,” said Julie Rentner, executive vice president of River Partners, a conservation group that is restoring hundreds of acres of farmland on the outskirts of Modesto in the Central Valley, where agriculture has overwhelmed the natural environment. “Now we’ve got this whole much larger public benefit thing going on.”
Researchers say it is unclear whether climate change will make California drier or wetter on average. What is more certain is that the state will increasingly whipsaw between extremes, with drier dry years, wetter wet ones and a rising frequency of intense periods of precipitation.
Climate models agree that “this really big increase in wet events is quite likely,” said Daniel Swain, a climate scientist at the University of California at Los Angeles and an author of a recent paper on the expected changes. “There’s just so much more moisture in the atmosphere in a warming world.”
As more so-called atmospheric river storms blow in from the Pacific Ocean, and more precipitation falls as rain rather than snow in the Sierra Nevada, where most of the state’s main rivers begin, increased runoff may force reservoir operators to release more water from dams or may otherwise cause flooding downstream.
River Partners’ project, Dos Rios, covers more than 3 square miles of farmland here at the confluence of the Tuolumne and San Joaquin rivers. It will benefit endangered animals like the riparian brush rabbit and birds