California Energy Commission Grant Brings Scientists Closer to Transformative Forecast Ability

The California Energy Commission (CEC) awarded $1.5 million to three University of California campuses to give California’s electricity utilities, other electricity sector stakeholders and state agencies the ability to better anticipate climate change phenomena.

For several years, researchers at Scripps Institution of Oceanography at UC San Diego and others have worked to apply computer simulations, or models, to “downscale” depictions of past and future climate to resolve what happens over short distances and shorter time periods within the complex coast, valley, mountain and desert landscapes that characterize California.

The statistical downscaling technique developed at Scripps has been used in California’s recent Fourth Climate Change Assessment as well as the National Climate Change Assessment. This technique offers the computational efficiency to provide model simulations covering a wide range of future climate scenarios.  Over the next 3-5 years, the CEC project will leverage improvements to the techniques used for California’s Fourth Climate Change Assessment to deliver products that utilities and other entities need as a basis for incorporating climate change into their long-range planning, said Scripps climate scientist Dan Cayan, who is principal investigator of the new project.

“By engaging California utility representatives and other stakeholders into the early stages of this effort, we will design the model runs and model output to help state electrical utilities improve a mandated set of climate change assessments of energy supply, demand, infrastructure, safety and their customer bases,” said Julie Kalansky, program manager for the California-Nevada Climate Applications Program at Scripps, who is also involved in the project.  “To support this effort, these new results will provide unparalleled spatial and temporal detail of projected climate change scenarios from new global model simulations.”

The grant comes at a point in history in which all five of the warmest years ever recorded across the planet have all occurred since 2015, and in the wake of a wildfire season in which the four million acres burned in California exceeded by twofold its previous record high.  The results of this effort, which will be made broadly available, will be a valuable resource that puts California’s technological capability to prepare for change on par with any other program in the world, Cayan said.

Downscaled climate model output will depict a range of atmosphere and land and ocean surface variables such as temperature, precipitation, wind, humidity, cloud cover, snow cover and soil moisture.  The results will cover the region of California and surrounding ocean and land area over the historical period covering the last several decades and over the future period from present through the end of the 21st century. With that sort of information, utilities will be able to better assess future impacts, including both long term changes and high impact extreme events.  The detailed nature of the climate modeling will underpin the analysis of conditions occurring in the hours preceding and during a possible future wildfire breakout or a large flood.

The latest version of the forecast product brings its spatial resolution from six kilometers (3.7 miles) to three kilometers (1.9 miles), which is an important advance in a state where topography and overlying weather and climate can change dramatically over short distances.  The model results will thus be better able to resolve the inland extent of the Pacific marine layer that provides natural air conditioning to the state’s coastal residents, and to delineate changes in the elevation where rain transitions to snow, which has traditionally supplied much of California’s summer water resources.

The project combines strengths of climate researchers across the UC system. Researchers from UCLA will provide a foundational contribution through dynamical modeling, using numerical models of the atmosphere and land surface to provide, for a limited set of model simulations, a full suite of atmospheric and land variables. In addition, UCLA researchers will use the downscale model projections to develop projections of stream flow, soil moisture and other hydrologic variables. Berkeley researchers will work on improving and sustaining interactions between scientists and end-users to make forecast products as targeted to their specific applications as possible.

The expertise provided by this team “addresses a range of climate modeling and applications needs aimed at [California’s] electrical utilities but will certainly also be useful … offer[ing] detailed climate projection information that is needed by other sectors,” Cayan said.