Decadal Summertime Fog & Coastal Low Cloud Dataset for North and Central Coastal California for 1999-2009

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Basic Information

The raster grids in this dataset show the relative amount of summertime fog and low cloud cover (FLCC) over a decade for North and Central Coastal California on either a monthly or annual basis. Summertime FLCC is calculated as the average FLCC hours per day from an archive of hourly, day and night, June, July, August, and September, 1999 - 2009, GOES (geostationary operational environmental satellite) images collected and processed into ~26, 000 cloud maps by the Cooperative Institute for Research in the Atmosphere (CIRA). These decadal average FLCC rasters do not include years 2001 and 2006 due to missing or incomplete data for June 2001 and August 2006.

Layers included:

Files Description
1 Decadal Summer (average of all 4 summer months over all available years)
2 Decadal Standard Deviation (SD) & Coefficient of Variance (CV) (for above average)
4 Decadal By Month (average for each summer month over all available years)
2 Decadal Daytime & Nighttime (average day/night for all 4 summer months over all available years)

The dataset also includes a (vector) contour layer, attached separately, that is an interpolated version of the Decadal Summer raster above.

For more information about this data and the Pacific Coastal Fog Project, see and this article at

You may download the dataset below. For questions, please contact Alicia Torregrosa

Please use the following citation when using this dataset: Torregrosa, A., C. Combs, and J. Peters (2016), GOES-derived fog and low cloud indices for coastal north and central California ecological analyses, Earth and Space Science, 3, doi:10.1002/2015EA000119. *******Distributor assumes no liability for misuse of data.*******
Alicia Torregrosa
org: California LCC USGS Land Change Science, Cooperative Institute for Research on the Atmosphere, California Landscape Conservation Cooperative, TBC3 -Pepperwood Preserve, and Gordon and Betty Moore Foundation.
USGS and Climate Commons
Data Type:
Spatial Resolution: 
4 km
Temporal Coverage: 
Date Issued: 
Feb. 2016

Two dataset zipfiles are available for download below.
One is a zipfile containing 11 ESRI raster grids with grid cell values indicating hours per day of fog and low cloud cover (described above).
The other is a zipfile containing a vector shapefile and a layer file to depict a contour map of hours per day of fog and low cloud cover in 30-minute intervals. The contours are derived from the average decadal summertime raster.

Parameters / Choices
A dataset often contains many geodata layers representing the same kind of measurement, but for different values of some parameters - time periods, models or scenarios, different species, etc. A value must be chosen for each such parameter in order to select a specific layer or raster which associated a single value with each geographic location (cell). The parameters or choices relevant to selecting layers from this dataset are described here.
Time Units: 
One layer, 11 year summary
File Attachments