Download GCOS and ECVs – Some background

GCOS and ECVs – Some background
23 January 2012
Michele Walters, Henrique Pereira, Simon Ferrier, Rob Jongman and Gary Geller
(EBV Coordination Committee)
Since we plan to take example from GCOS and their ECVs for development of EBVs, a bit of
background information is provided.
Origin and purpose of GCOS
The Global Climate Observing System (GCOS) was established, in 1992, in parallel with the negotiation of the
UNFCCC, as a joint initiative of the World Meteorological Organization (WMO), the Intergovernmental
Oceanographic Commissions (IOC) of UNESCO, the United Nations Environment Programme (UNEP) and the
International Council for Science (ICSU).
The stated purpose of GCOS is to meet the total national and international needs for comprehensive,
continuous, reliable climate and climate related data and information.
In particular, at the international level, GCOS is designed to support:
The specific observational needs of the World Climate Programme and related earth system science
and service programs;
The climate change assessment role of the Intergovernmental Panel on Climate Change (IPCC); and
The requirements of the UNFCCC and other international conventions and agreements.
The goal of GCOS is to provide comprehensive information on the total climate system, involving a
multidisciplinary range of physical, chemical and biological properties, and atmospheric, oceanic, hydrologic,
cryospheric and terrestrial processes.
Essential Climate Variables (ECVs): some facts
The concept of Essential Climate Variables (ECVs) was developed some ten years ago. They were first listed in
the Second Report on the Adequacy of the Global Observing Systems for Climate in Support of the UNFCCC
published in 2003.
The 2004 Implementation Plan for the Global Observing System for Climate in Support of the UNFCCC (IP-04)
and its 2006 Satellite Supplement use the list of ECVs as the basis for their detailed specifications of
requirements, which are provided variable by variable. Much of the rationale for the designation of the set of
ECVs is contained within these documents.
Since then the ECVs have achieved increasing recognition. For example, they now provide the basis for
national reporting on systematic observation by Parties to the UNFCCC, provide a basis for the organisation of
the ESA Climate Change Initiative, and increasingly appear in calls for proposals under the European Union’s
7th Framework Programme.
The list of ECVs was revised in the 2010 update of IP-04 (IP-10). The updated list of ECVs (see below) now
includes variables not previously on the list and a few variables were renamed. In making these changes, it
was recognised that revision of the list was not something to be taken lightly, given that it formed the basis
for an increasing number of activities. As was the case with earlier documents, IP-10 was subject to a period
of public review before being finalised.
Some ECVs relate to specific state variables such as temperature or surface pressure, whereas some refer not
to a specific well-defined variable, but rather a class of variables.
GCOS has a roughly five-year cycle for assessment and implementation planning when the list is reviewed.
The current list of ECVs
Domain
Essential Climate Variables
Atmospheric
(over land,
sea and ice)
Surface:
Air temperature, Precipitation, Air pressure, Surface radiation
budget, Wind speed and direction, Water vapour.
Upper-air:
Earth radiation budget (including solar irradiance), Upper-air
temperature, Wind speed and direction, Water vapour, Cloud
properties.
Composition:
Carbon dioxide, Methane, Ozone, Other long-lived greenhouse
gases, Aerosol properties.
Surface:
Sea-surface temperature, Sea-surface salinity, Sea level, Sea
state, Sea ice, Current, Ocean colour (for biological activity),
Carbon dioxide partial pressure.
Sub-surface:
Temperature, Salinity, Current, Nutrients, Carbon, Ocean tracers,
Phytoplankton.
Oceanic
Terrestrial
River discharge, Water use, Ground water, Lake levels, Snow cover, Glaciers and
ice caps, Permafrost and seasonally-frozen ground, Albedo, Land cover (including
vegetation type), Fraction of absorbed photosynthetically active radiation, Leaf area
index, Biomass, Fire disturbance, Soil moisture 4 .
More information
A summary can be found here:
http://www.wmo.int/pages/prog/gcos/Publications/GCOS_flyer_MonitoringPrinciples&ECVs.pdf
Updated 2010 Implementation Plan can be found here:
http://www.wmo.int/pages/prog/gcos/Publications/gcos-138.pdf