Climate change scenario projection and assessment of uncertainties

WP coordination: Institut Pierre Simon Laplace (Laurent Li)

The workpackage 1 of CLAVIER is designed to perform climate change simulations, to assess uncertainties, and to provide relevant future climate scenarios for impact communities. Three main partners are involved in this WP: IPSL in Paris, MPI-M in Hamburg and OMSZ in Budapest. Other partners, such as NIMH in Sofia, are involved in diagnosing and analysing numerical simulations performed in the WP1.

The mandatory simulations performed by the engaged groups consist of an ensemble of 8 simulations covering the period 1951 to 2050. This ensemble is the cross product of 2 greenhouse-gas-emission scenarios (A1B and B1 from IPCC), 2 global ocean-atmosphere-coupled models (MPI-M and IPSL), and 2 regionally-oriented climate models (REMO from MPI-M and LMDZ from IPSL). Such an exhaustive combination is a "perfect" design to evaluate the spread and uncertainties existing in the three distinct stages of regional climate change information production: emissions, global models and regional models.

Model validation is the second main task that WP1 deals with. Both REMO and LMDZ are nudged into the ERA40 reanalysis dataset, in order to reproduce the long sequence of climate variation during the last 40 years. It is expected to find new discrepancies for models when compared to station-based observations. But we are prepared to such a result, since careful analysis of physical mechanisms responsible for models mis-behaviour will help us to improve the models and to make an uncertainty evaluation and a cautionary judgement for future-climate scenarios.

WP1 is in strong coordination with other workpackages of CLAVIER, especially the interfacing WP 2, in order to perform other relevant simulations to study physical processes and practical methodologies for climate information transfer across different spatio-temporal scales. MPI-M is planning to run a higher-resolution REMO simulation forced by the same REMO model but with a lower resolution. IPSL is planning to use an innovative protocol to run a large number of A2 scenarios from at least 4 global ocean-atmosphere models. This protocol tries to explore the zoom characteristics of LMDZ which can be run with the surface boundary conditions only and without any lateral boundaries.

Results of WP1

Status of WP1 Tasks (internal)