COsmic-ray Soil Moisture Interaction Code (COSMIC)
Date: August 2013
The COsmic-ray Soil Moisture Interaction Code (COSMIC) is a simple, physically based and analytic model used for data assimilation applications of cosmic-ray soil moisture sensors. The model includes simple descriptions of (a) degradation of the incoming high-energy neutron flux with soil depth, (b) creation of fast neutrons at each depth in the soil, and (c) scattering of the resulting fast neutrons before they reach the soil surface, all of which processes may have parameterized dependency on the chemistry and moisture content of the soil (see below).
The three physical processes represented in the COSMIC that control the above ground fast neutron count rate.