The California Department of Water Resources is responsible for issuing forecasts of streamflow volume for 20 major river basins across the state. However, in addition to a declining snowpack in the Western U.S., the statistical models used in water forecasting are subject to significant error and are causing significant management challenges in California. The adaptability of water resource management strategies to these climatic shifts is impeded, in part, by a reliance on the aforementioned empirical runoff forecast models and the sparse in situ sampling of snowpack conditions. This research project address these impediments through real-time integration of MODIS-based SWE estimates into water supply forecast models. Please reference the Real-Time SWE Reports created by INSTAAR's Mountain Hydrology Group for weekly real time SWE simultaion reports in the Sierra Nevada Mountains, CA.  Real Time SWE Reports

CWEST Participants: Noah Molotch, David Rizzardo of CA Department of Water Resources, Bin Guan of JPL, Leanne Lestak and Dominik Schneider

Ingestion of MODIS-based snow water equivalent (SWE) estimates into water supply forecast models

Estimated % of average SWE across the Sierra Nevada

Estimated % of average SWE across the Sierra Nevada. Percent of average (2000-2011) SWE for April 1, 2018 for the Sierra Nevada, calculated for each pixel (left) and basinwide (right). Basinwide percent of average is calculated across all model pixels >5000’ elevation.

Using MODIS-based SWE estimates, the primary objective of this research is to improve operational forecasting of water supply for major river basins of the Sierra Nevada Mountains, California. Related secondary and tertiary objectives aim to migrate SWE product Analyses into CA DWR computational environments and to conduct quantitative and qualitative assessment of the utility of the MODIS snowpack information with regard to water resource decisions. California is highly dependent on snowmelt runoff for municipal, agricultural, and hydropower water demands, particularly from the Sierra Nevada Mountains. This research will provide a framework as to how improved snowpack information can be used to improve water supply forecasts


California’s Water Education Foundation produced a Western Water magazine article detailing some of DWR’s uses of remotely sensed data. For more information about the different methods and uses of remotely sensed data, like that of MODIS, read Gary Pitzer’s article, “The View from Above: The Promise of Remote Sensing.” More information can be found on the California's Department of Water Resources website, and the NASA's MODIS website.