GCOS Essential Climate Variables (ECV) Data Access Matrix

The Essential Climate Variables (ECV) Data Access Matrix provides easy access to ECV data sets and information. The input for the variable descriptions were provided by WMO/GCOS. Essential Climate Variables are required to support the work of the United Nations Framework Convention on Climate Change (UNFCCC) and the Intergovernmental Panel on Climate Change (IPCC). All Essential Climate Variables are technically and economically feasible for systematic observation. It is these variables for which international exchange is required for both current and historical observations. It is emphasized that the ordering within the table is simply for convenience and is not an indicator of relative priority. There are currently 50 Essential Climate Variables.

Latest:

The State of the Climate in 2011 data sets are presently being added to the Matrix (** indicates data are available). These data sets are part of the peer-reviewed articles in the supplement to the Bulletin of the American Meteorological Society (BAMS) July 2012 issue (Vol. 93, No. 7). More information
Summary Report of the Fifteenth Session of the GCOS/WCRP Terrestrial Observation Panel for Climate (TOPC), Geneva, Switzerland, 6-7 March 2013

Latest Update May 20, 2013

ATMOSPHERIC (over Land, Sea & Ice)	OCEANIC	TERRESTRIAL [2]
Surface [4]	Surface [6]	River Discharge **
Surface Air Pressure	Carbon Dioxide Partial Pressure	Water Use
Surface Air Temperature	Current **	Ground Water
Surface Precipitation	Ocean Acidity *	Lakes (Water level in lakes and reservoirs, water storage) * **
Surface Radiation Budget	Ocean Color **	Snow Cover **
Water Vapour (Surface humidity)	Phytoplankton *	Glaciers and Ice Caps *
Near-Surface Wind Speed and Direction	Sea Ice	Permafrost and seasonally frozen ground
Upper-Air *[5]*	Sea Level **	Albedo and Reflectance Anisotropy * **
Cloud Properties **	Sea State	Land Cover (including Vegetation Type)
Earth Radiation Budget (including Solar Irradiance) *	Sea Surface Salinity (SSS) **	Fraction of Absorbed Photosynthetically Active Radiation (FAPAR) **
Temperature	Sea Surface Temperature (SST) **	Leaf Area Index (LAI)
Water Vapor **	Sub-Surface	Above Ground Biomass *
Wind Speed and Direction	Carbon	Fire Disturbance **
Composition	Current	Soil Moisture * **
Aerosols Properties **	Nutrients	Soil Carbon *
Carbon Dioxide	Ocean Acidity *	Ice Sheets *
Methane and other Long-Lived Green House Gases [1]	Oxygen *
Ozone **	Salinity
Precursors (supporting the Aerosols and Ozone ECVs) [3] *	Temperature
	Tracers
	Global Ocean Heat Content ***

* Added or modified per 'Implementation Plan for the Global Observing System for Climate in Support of the UNFCCC - August 2010, GCOS-138 (GOOS-184, GTOS-76, WMO-TD/No. 1523)' (page 19) (pdf)
** State of the Climate in 2011 data available
*** Not an official GCOS ECV

[1] The 'Other long-lived greenhouse gases' ECV includes Nitrous Oxide (N₂O), Chlorofluorocarbons (CFCs), Hydrochlorofluorocarbons (HCFCs), Hydrofluorocarbons (HFCs), Sulphur hexafluoride (SF₆), and Perfluorocarbons (PFCs).
[2] Includes Runoff (m³ s^-1), Ground Water Extraction Rates (m³ yr^-1) and Location, Snow Cover Extent (km²) and Duration, Snow Depth (cm), Glacier/Ice Cap Inventory and Mass Balance (kg m^-2 yr^-1), Glacier Length (m), Ice Sheet Mass Balance (kg m^-2 yr^-1) and Extent (km²), Permafrost Extent (km²), Temperature Profiles and Active Layer Thickness, above ground Biomass (t/ha), Burnt Area (ha), Date and Location of Active Fire, Burn Efficiency (% Vegetation Burned/Unit Area)
[3] NO₂, SO₂, HCHO, CO
[4] including measurements at standardized but globally varying height in close proximity to the surface
[5] Up to the stratopause
[6] Including measurements with the surface mixed layer, usually with the upper 15 meters