IPCC AR4 Simulations: Background Information
Simulations for the IPCC
AR4
(Fourth Assessment Report des Intergovernmental Panel of Climate
Change)
In 2004 approximately a quarter of the available computing resources on HLRE (thus 6 NEC SX-6 nodes operating 24 hours the day) were used for complex model calculations whose results contribute to the the fourth Assessment Report (AR4) of the Intergovernmental Panel on Climate Change (IPCC) - scheduled for early 2007. In these Assessment Reports by the IPCC (see also www.ipcc.ch), being published every 5 years, the actual knowledge on the state and the expected changes of climate are summarised.
The simulations are realised with the coupled atmosphere ocean model ECHAM5 / MPI-OM developed at MPI-M. The atmosperic model component ECHAM5 has a horizontal resolution of approximately 200 km with vertically 31 model levels. The ocean model MPI-OM is used with a regionally varying horizontal resolution between approximately 10 km and 150 km.
The results of the simulations, carried out for the German Community by the MPI-M and the Model and Data Group, were stored operationally in a relational database. They are available to scientists for further analysis. The model output of the new IPCC simulations, which were stored until the beginning of 2005 in the climate database, amount to more than 120 TeraBytes, thus 120,000 GigaBytes! The data are made available by the World Data Center for Climate (WDCC) and can be accessed on http://ipcc.wdc-climate.de.
The results of the climate change simulations for different emission scenarios arouse particularely the public interest. How could climate develop in the next 100 years?
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The figure displays three different scenarios for the CO2-concentration based on different assumptions for emissions which are controlled by different economic and political developments. Here not shown - however considered within the simulations - are also other greenhouse gases and aerosols. |
In the section Results you will find figures and animations showing first results of the simulations.
Further information about these simulations and the decision of the WLA (Wissenschaftlicher Lenkungsausschuss; Scientific Advisory Panel) concerning the provision of the neccesary computing resources are to be found in the Minutes of the IPCC Planning Workshop (in German) from May 2004 and in the Issue No.5 and No.6 of our newsletter TerraFlops.