Precambrian Climate Dynamics

This award supports an investigation of the climate of the Precambrian era (600 million to 4 billion years ago). This investigation of climate has two major efforts: 1. Clarify the long standing paradox of the faint young sun and the climate evolution of the earth's atmosphere, and 2. Examine current climate theory in light of the great changes in parameters of the Precambrian. The geologic and planetary records have definite evidence for four earth parameter changes of consequence for Precambrian climate: a smaller solar luminosity , a faster Earth rotation rate, a different atmospheric composition and a much reduced land area. Because of the critical importance of the hydrologic cycle and eddy properties found in previous studies, this study will use GCM modeling with the NCAR Community Climate Model. Profound changes in the general circulation found in the Precambrian offer a fundamental way to study current climate balances and the current climate state of the Earth.