GCOS Implementation Plan - WMO

Implementation Plan for the Global Observing System for Climate in Support of the UNFCCC
(2010 Update)
Many of the current research satellite missions have demonstrated the potential of new instruments to
better meet climate and other needs. Seeking effective means of maintaining long-term operation and
continuity of these instruments will be critical to the achievement of this Plan. From this global
foundation, higher-resolution comprehensive networks and analysis products enhance the
observational resource and build functionality that allows for application on regional and national
scales as appropriate.
As previously discussed, the GCOS is being implemented primarily through the setting of climaterelevant
standards and requirements for its main component observing systems, e.g., WIGOS,
GOOS, GTOS, etc. Many of the networks and systems contributing to the GCOS or that could
potentially contribute to it have been designed and operated to address other applications. Many of
these can, however, serve as major contributors to GCOS, sometimes through straightforward,
operational changes such as providing adequate metadata, ensuring that the instrument and
observing platform or station operation follows the GCMPs, and/or by the systematic submission of
data to the specified International Data Centres.
Thus, the GCOS will require a composite of surface-based, sub-surface ocean, airborne in situ and
remotely-sensed data, and satellite data and products in order to yield comprehensive information for
all three domains (atmospheric, oceanic and terrestrial). It will also require data acquisition
procedures following the GCMPs and data and information products available through internationallydesignated
data and analysis centres. This integration often occurs on a variable-by-variable basis
and on two broad time-frames. The first is real time or near-real time for monitoring and prediction
purposes and for providing quality control and essential feedback to the observers and system
operators. The second is the delayed mode, where historical data are also incorporated, usually as
part of an analysis or as part of ongoing research on climate variability and change.
Data assimilation is a technique that adds considerable value to global observing systems by
combining heterogeneous sets of observations (e.g., in situ and remotely-sensed measurements) as
well as using global numerical models to incorporate other ECVs into consistent analyses. These
analyses recognise the inter-relationships between variables and the errors associated with each
variable. Diagnostic data produced during the assimilation process provide information on the overall
quality of the analyses, including information on model biases, and can be used to identify
questionable data. At the same time, the production of more simple analyses from single-source data
obeying the GCMPs remains critical to ensuring or confirming the reliability of conclusions regarding
climate change over time.
Information on many atmospheric ECVs could in principle be obtained by accumulating the analyses
made each day to initiate numerical weather forecasts. However, the data assimilation systems used
in routine numerical forecasting are subject to frequent change as they are continually improved. This
introduces inhomogeneities in the analyses that limit their usefulness for studies of interannual and
longer-term variations in climate. To overcome this situation, programmes of atmospheric reanalysis
have been established mainly in Europe, Japan, and the USA using modern stable data assimilation
systems to reprocess all the available observations taken over the past several decades. Such
reanalysis products have found application in studies of climate, of basic atmospheric processes, and
of ocean-model initialisation and forcing. The extension of the reanalysis concept more fully to the
oceanic and terrestrial domains and to coupled atmosphere-ocean models and eventually to fully
coupled atmosphere-ocean-terrestrial models will be major steps in global climate monitoring. Another
dimension of the integrated approach is the extension of the climate record through the blending of
data from proxy reconstructions of past climates, using tree rings, sediment cores, ice cores, etc., with
the instrumental records of the last two centuries. The production of an accurate record of the current
global climate will assist enormously in the interpretation of the past record.
2.6. Building Capacity
The need for Parties to improve the global observing system for climate in developing countries has
been a common theme in the considerations by SBSTA on systematic observation. There are many
ways that systems can be improved, including through assistance by developed country agencies to
organizations and personnel from developing countries, the donation of equipment, the training of
personnel, etc. The building of capacity to utilise data and to ensure that all countries fully benefit from
the GCOS also needs to accompany this strengthening of observation activities. The GCOS Regional
Workshop Programme, noted in section 3.1.2 below, constituted a major effort that the GCOS
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