In California, Large-scale Water Cycles Impact Quakes A Little (image) American Association for the Advancement of Science Share Print E-Mail Caption Water storage estimated from the regional GPS network throughout central and northern California shown as average water-layer thickness on a 25 km grid. The summer months experience a loss of water in the Sierra Nevada and Central Valley that is replenished in the mountains during the wet winter months as reservoirs fill and snow accumulates. In the Central Valley, water storage has been continuously decreasing due to large scale agriculture. The seasonal change in mass deforms the crust and the associated stress changes modulate regional seismicity. This material relates to a paper that appeared in the 16 June 2017, issue of Science, published by AAAS. The paper, by C.W. Johnson at University of California, Berkeley in Berkeley, CA, and colleagues was titled, "Seasonal water storage, stress modulation, and California seismicity." Credit Image produced by Christopher Johnson, Berkeley Seismological Laboratory Usage Restrictions Please cite the owner of the material when publishing. This material may be freely used by reporters as part of news coverage, with proper attribution. Non-reporters must contact Science for permission. Share Print E-Mail Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.