The DDC provides four main types of data and guidance, which meet certain
criteria laid down by the TGICA. They are introduced
briefly here and described in more detail throughout the web site and
1. Observed Climate Data Sets
The climate observations
comprise 1961-1990 mean monthly data over global land
areas for nine variables on a 0.5º latitude/longitude grid, together with decadal
anomalies from this mean for the period 1901-1995. This data set is currently being updated
to 2000 and interpolated to a finer resolution (10 x 10 arc minutes). Pointers are provided
to other relevant global climatologies.
2. Global Climate Model Data
Global climate model data is available as
Data is held for climate model projections used as input to the Second, Third and Fourth IPCC Assessment Reports.
Full details of the variables held can be found on the relevant data pages.
The climatologies aof climate model projections can also be viewed through the
DDC visualisation service
Daily fields are not provided by the DDC, but are available from PCMDI
the respective modelling centres.
3. Socio-economic data and scenarios
Socio-economic data and scenarios
are required for describing socioeconomic development and adaptation capacity. The
reference data include country and regional level indicators of socio-economic and resource variables.
The scenario data supplied extend to 2100 and are based on the assumptions underlying the new set of
emissions scenarios developed for the IPCC Special Report on Emissions Scenarios,
as well as the
six IS92 emissions
scenarios prepared by the IPCC in 1992
There is also detailed
on the use of DDC data to develop socio-economic and adaptation scenarios as well as links to related
guidance material developed by other agencies.
4. Data and scenarios for other environmental changes
Some data and information for other environmental changes
is also included in
These include data on global mean CO2 concentration, global and regional sea-level rise,
regional ground-level ozone concentration, sulphate aerosol concentration and sulphur
deposition. All of these scenarios were developed for the IPCC Third Assessment Report based on
the SRES emissions scenarios. Detailed documentation and guidance is also provided for the use
of these data.