Rock-Ice Feature Inventory for the Sierra Nevada, California, USA, Version 1

Mean annual minima ranged from -8.1 to -0.4 oC, January from -15 to -7 oC, and July from 1.2 to 8.9 oC. The highest temperatures and lowest precipitation were largely at relict Pleistocene rock glaciers, which tended to be farthest east of the Sierran crest and lower in elevation. We mapped over 430 RIFs, based on field surveys and grouped them into six classes based on morphology and location.

These categories constitute a greater range of frozen-ground features than are commonly described in rock-glacier surveys. Although granitic substrates dominate the Sierra Nevada, they do not in the eastern escarpment, so substrates in the RIF database are about equally divided between granitic and metamorphic. Ages of rock glaciers ranged from current (active) to relict (late Pleistocene).

We interpreted the presence of outlet springs, basal lakes, suspended silt in outlet streams, and fringing phreatophytic vegetation, in addition to morphologic indications of current rock movement, as evidence for interstitial ice, either persistent or seasonal. One comma-delimited ASCII file containing information for 430 rock-ice features is available.