Some Acronym's and Terms We'll be Using

Community Atmosphere Model (CAM). The prognostically active atmosphere model component of CESM.

Community Earth System Model (CESM). The coupled earth system model that CLM is a component of.

Community Land Model (CLM). The prognostically active land model component of CESM.

Community Land Model (CLM4.5) with BGC Biogeochemistry. Uses CN Biogeochemistry with vertically resolved soil Carbon, CENTURY model like pools, and Nitrification/De-Nitrification. The CLM_CONFIG_OPTS option for this is

./xmlchange CLM_CONFIG_OPTS="phys clm4_5 -bgc cn -vsoilc_centbgc on -clm4me on"

Community Land Model (CLM) with Carbon Nitrogen (CN) Biogeochemistry (either CLM4.0 or CLM4.5) The CLM_CONFIG_OPTS option for this is

./xmlchange CLM_CONFIG_OPTS="-bgc cn" -append

Community Land Model (CLM) with Satellite Phenology (SP) (either CLM4.0 or CLM4.5) The CLM_CONFIG_OPTS option for this is

./xmlchange CLM_CONFIG_OPTS="-bgc none" -append

Community Land Model (CLM) Urban Model (either CLM4.0 or CLM4.5). The urban model component of CLM is ALWAYS active (unless you create special surface datasets that have zero urban percent, or for regional/single-point simulations for a non-urban area).

The Climate Research Unit (CRU) analysis of the NCEP atmosphere reanalysis atmosphere forcing data. This can be used to drive CLM with atmosphere forcing from 1901 to 2010. We also DO expect to be able to update this dataset beyond 2010 as newer data becomes available.

Data Atmosphere Model (DATM) the prescribed data atmosphere component for CESM. Forcing data that we provide are either the Qian or CRUNCEP forcing datasets (see below).

Dynamic global vegetation, where fractional PFT (see PFT below) changes in time prognostically. Can NOT be used with prescribed transient PFT (requires either CLM4.5-BGC or CLMCN for either CLM4.0 or CLM4.5). The CLM_CONFIG_OPTS option for this is

./xmlchange CLM_CONFIG_OPTS="-bgc cndv" -append

Earth System Modeling Framework (ESMF). They are a software project that provides a software library to support Earth System modeling. We provide interfaces for ESMF as well as use their regridding capabilities for offline CLM tools.

National Center for Atmospheric Research (NCAR). This is the research facility that maintains CLM with contributions from other national labs and Universities.

The National Center for Environmental Prediction (NCEP). In this document this normally refers to the reanalysis atmosphere data produced by NCEP.

Plant Function Type (PFT). A type of vegetation that CLM parameterizes.

PoinT CLM (PTCLM) a python script that operates on top of CLM for CLM4.5 to run single point simulations for CLM.

The Qian et. al. analysis of the NCEP forcing data. This can be used to drive CLM with atmosphere forcing from 1948 to 2004. We do NOT expect to be able to update this dataset beyond 2004.

Spherical Coordinate Remapping and Interpolation Package (SCRIP). We use it's file format for specifying both grid coordinates as well as mapping between different grids.

Variable Infiltration Capacity (VIC) model for hydrology. This is an option to CLM4.5 in place of the standard CLM4.5 hydrology. The CLM_CONFIG_OPTS option for this is

./xmlchange CLM_CONFIG_OPTS="-vichydro on" -append