Habitat Compression Index

"The habitat compression index uses 2 m temperature from the historic and NRT data assimilative ROMS physical model of the California Current system (<a href="oceanmodeling.ucsc.edu/index.html" target="_blank">oceanmodeling.ucsc.edu/index.html</a>). Grid points between 30-48 degrees N and from the shore out to 150 km offshore are used in the analysis. Additional Calculations: In eastern boundary upwelling ecosystems the spatial footprint of cool upwelled water is regularly demarcated by the differential boundary of warmer oceanic water offshore from cooler coastal water, with upwelling conditions varying with latitude.

Therefore, the goal of the habitat compression index (HCI) is to track the area of cool surface waters as an index of potential 'upwelling habitat' for assessing the spatio-temporal aspects of upwelling. Upwelling patterns of cold nutrient-rich water are clearly assessed by models and satellite observations and classified spatially by monitoring SST values less than and equal to a monthly resolved temperature threshold.