4DDA four-dimensional data assimilation

ABLE Atmospheric Boundary Layer Experiments (CART/ARM/DOE)

ACC Anthropogenic Climate Change (CLIVAR program area)

ACSYS Arctic Climate System Study (WCRP)

ADEOS II Advanced Earth Observing Satellite-II

AGU American Geophysical Union

AHPS Advanced Hydrological Prediction System (OH/NWS)

AIMS analysis, interpretation, modeling, and synthesis

AIRS Advanced Infrared Sounder

AMIP Atmospheric Model Intercomparison Project

AMSR Advanced Microwave Scanning Radiometer

AMSU Advanced Microwave Sounding Unit

APDA Arctic Precipitation Data Archive (ACSYS)

ARDB Arctic Runoff Data Base (ACSYS/GRDC)

ARM Atmospheric Radiation Measurement (DOE)

ARO Army Research Office

ARS Agricultural Research Service (USDA)

ASTER Advanced Spaceborne Thermal Emission and Reflection Radiometer

AVHRR Advanced Very High Resolution Radiometer

BAHC Biospheric Aspects of the Hydrologic Cycle (IGBP project)

BALTEX Baltic Sea Experiment

BERMS Boreal Ecosystem Research and Monitoring Sites

BoR U.S. Bureau of Reclamation

BOREAS Boreal Ecoystem-Atmosphere Study (NASA)

CAMEX Convection And Moisture EXperiment

CART Cloud and Radiation Testbed (ARM/DOE)

CASES Cooperative Atmosphere-Surface Exchange Study

CLIC Climate and Cryosphere (new WCRP program)

CLIVAR Climate Variability and Predictability (WCRP program)

Cloudsat NASA mission to measure the vertical structure of clouds from space

COWL cold-ocean/warm-land (pattern of temperature change)

CPC Climate Prediction Center (NCEP/NWS)

CRM cloud-resolving model

CSE continental-scale experiment

DAAC Distributed Active Archive Center (NASA)

DAO Data Assimilation Office (NASA)

DEM digital elevation models

DenCen Decadal to Centennial Climate Variability (CLIVAR program area)

DOC dissolved organic carbon

DOD U.S. Department of Defense

DOE U.S. Department of Energy

ECMWF European Center for Medium Range Weather Forecasts

EOS Earth Observing System (NASA)

EMAP Environmental Monitoring and Assessment Program (EPA)

EMC Environmental Modeling Center (NCEP/NWS)

ENSO El Niño -- Southern Oscillation

EPA U.S. Environmental Protection Agency

ERDC Engineer Research and Development Center (USACE)

ESE Earth Science Enterprise (NASA)

FAO UN Food and Agriculture Organization

FEMA Federal Emergency Management Agency

FIFE First ISLSCP Field Experiment

FIRE First ISCCP Regional Experiment

FS Forest Service (USDA)

GAME GEWEX Asian Monsoon Experiment

GAPP GEWEX America Prediction Project (NASA/NOAA)

GCIP Continental-Scale International Experiment (GEWEX/WCRP)

GCM general circulation model

GCOS Global Climate Observing System (WMO)

GCTE Global Change and Terrestrial Ecosystems (IGBP project)

GEWEC Global Water and Energy Cycle (ESE/NASA)

GEWEX Global Energy and Water Cycle Experiment (WCRP)

GHP GEWEX Hydrometeorological Panel

GIS geographic information systems

GLASS Global Land-Atmosphere System Study (GEWEX/WCRP )

GLIMS Global Land Ice Measurements from Space

GOALS Global Ocean Atmosphere Land System (CLIVAR program area)

GODAE Global Ocean Data Assimilation Experiment

GOES Geostationary Operational Environmental Satellite

GOOS Global Ocean Observing System

GPCP global precipitation climatology project (GEWEX)

GPM Global Precipitation Mission (NASA)

GRDC Global Runoff Data Center (Germany)

GSFC Goddard Space Flight Center (NASA)

GSWP Global Soil Wetness Project

GTOS Global Terrestrial Observing System (FAO)

GTS Global Telecommunication System (WMO)

GVaP GEWEX Water Vapor Project

HAPEX Hydrology Atmosphere Pilot Experiment

HEC Hydrologic Engineering Center (USACE)

HELP Hydrology for Environment, Life and Policy (UNESCO/WMO)

HWRP Hydrology and Water Resources Program (WMO)

HYDRA-SAT Hydrologic Altimetry Satellite

IAHS International Association of Hydrological Sciences

ICSU International Council of Scientific Unions

IGBP International Geosphere Biosphere Program (ICSU)

IHD International Hydrological Decade (UNESCO)

IHDP International Human Dimensions Program (ICSU)

IHP International Hydrological Program (UNESCO)

IOC Intergovernmental Oceanographic Commission (UNESCO)

IOP intensive observation periods

IPCC Intergovernmental Panel on Climate Change (WMO/UNEP)

ISCCP International Satellite Cloud Climatology Project NASA)

ISLSCP International Satellite Land Surface Climatology Project

IWG interagency working group

IWR Institute for Water Resources (USACE)

LBA Large-Scale Biosphere-Atmosphere (Government of Brazil/ NASA/ EU -- international research program

LDAS Land Data Assimilation System

LSP land surface parameterization

LST land surface temperature

LTER Long-Term Ecolocical Research (NSF)

LUCC Land Use and Cover Change (IGBP project)

MAGS Mackenzie GEWEX Study (Canadian study)

MOBILHY Modelisation du Bilan Hydrique (HAPEX field study in France)

MODIS Moderate Resolution Imaging Spectroradiometer

MSL mean sea level

NAO North Atlantic Oscillation

NASA National Aeronautics & Space Administration

NAWQA National Water Quality Assessment (USGS)

NCAR National Center for Atmospheric Research

NCEP National Centers for Environmental Prediction (NWS)

NDVI Normalized Difference Vegetation Index

NEE Net Ecosystem Exchange

NEON National Ecological Observation Network (NSF)

NESDIS National Environmental Satellite, Data, and Information Service (NOAA)

NEXRAD Next Generation Weather Radar

NGO nongovernmental organization

NHSs national hydrological services

NMSs national meteorological services

NOAA National Oceanic & Atmospheric Administration

NPOESS National Polar-orbiting Operational. Environmental Satellite System

NPP Net primary productivity

NRC National Research Council

NRP National Research Program (USGS)

NSF National Science Foundation

NSIDC National Snow and Ice Data Center

NWS National Weather Service

OGP Office of Global Programs (NOAA)

OH Office of Hydrology (NWS)

PACS Pan American Climate Study

PAGES Past Global Changes

PARCA Program for Arctic Regional Climate Assessment (NOAA)

PNA Pacific -- North American (teleconnection pattern)

PICASSO/ Pathfinder Instruments for Cloud and Aerosol Space-

CENA bourne Observations/Climatologie Etendue des Nuages et des Aerosols (joint NASA/ESA satellite mission)

PILPS Project for the Intercomparison of Landsurface Parameterization Schemes

PRA principal research areas

RCUs regional coordinating units (HELP)

SeaWIFS Sea-viewing Wide Field-of-view Sensor (NASA)

SGP Southern Great Plains

SMOS Soil Moisture and Ocean Salinity (possible measuring mission; European Space Agency)

SNOTEL SNOw TELemetery (NRCS)

SPARC Stratospheric Processes and their Role in Climate (WCRP-sponsored program)

SSM/I Special Sensor Microwave Imager (DOD)

SST sea surface temperature

SURFRAD Surface Radiation Budget Monitoring Network (NOAA)

SWE snow water equivalent

TRMM Tropical Rainfall Monitoring Mission

UNEP United Nations Environment Program

UNFCCC UN Framework Convention on Climate Change

USACE U.S. Army Corps of Engineers

USDA U.S. Department of Agriculture

USGCRP U.S. Global Change Research Program

USGS U.S. Geological Survey

USWRP US Weather Research Program

UT/LS upper troposphere/lower stratosphere

UV ultraviolet

VAMOS Variability of the American Monsoon Systems (CLIVAR-related activity)

WCP World Climate Program

WCRP World Climate Research Program

WCSG Water Cycle Study Group (authors of this report)

WEAVE Water and Energy -- Atmospheric, Vegetative, and Earth Interactions (NSF)

WEBB Water, Energy, and Biogeochemical Budgets (USGS)

WGMS World Glacier Monitoring Service

WMO World Meteorological Organization

WOCE World Ocean Circulation Experiment

WRD Water Resources Division (USGS)

WWW World Weather Watch