DMP Section Type:
Data Input - Existing Collection
Description:
Interpolations of 20th century climate values from PRISM (monthly precipitation, minimum temperature, & maximum temperature) were downscaled from 4km grid cells to 270m grid cells using methods described in Flint and Flint 2012. These were used, along with other GIS layers (e.g. geology), as input for a version of the Basin Characterization Model (Flint and Flint 2007), to provide additional estimates of Actual Evapotranspiration (AET), Potential Evapotranspiration (PET) , Climatic Water Deficit (CWD) and Snow Water Equivalent (SWE).
Furthermore, four projections of monthly 21st century climate based upon two circulation models (NCAR Parallel Climate Model, PCM, and NOAA Geophysical Fluids Dynamics Laboratory model, GFDL) and two scenarios (A2, a higher emission scenario, and B1, an ecological friendly scenario), were available with the same variable suite.
The data encompassed the all watersheds associated with California.
Source:
We received the data directly for Alan and Lorraine Flint.
Processing & Workflow:
To speed processing, we clipped the data to a rectangular region that would encompass the Sierra Nevada and surrounding areas.
We used two thirty year periods of observed climate, 1910-1939 (historic) and 1970-1999 (modern), and three periods in future estimates, 2010-2039, 2040-2069, and 2070-2099, to summarize trends. For climate information, we constructed bioclimatic variables associated with each time period using the R package raster. We determined the extreme values during the historic time and determined the frequency in which modern and future periods exceeded them.
We summarized CWD & AET for each year within the dataset, and then determined the mean for each of the periods.
Backup & Storage:
Data are stored on external drives and on servers at the Museum of Vertebrate Zoology at UC Berkeley.
Citation:
Flint and Flint: Downscaling future climate scenarios to fine scales for hydrologic and ecological modeling and analysis. Ecological Processes 1:2. doi:10.1186/2192-1709-1-2
