TWP3 - ASSESSMENT OF UNCERTAINTY IN CLIMATE DIAGNOSTICS AND PROJECTIONS

Responsable : Pascale Braconnot, LSCE

Objectifs et stratégie

The objective of this transverse work package it to strengthen strategies and methodologies across the different WP for assessing the uncertainties associated to climate diagnostics and projections.  The work is divided into two major tasks. The first one will make use of scientific expertise developed in the different WP to improve the characterisation of the cascade of uncertainties from the climate forcings to the regional climate response focussing on model skill and the understanding of model uncertainties. The second will provide the scientific ground, climate indicators and methods that are needed to characterise the uncertainties in the different model outputs and to evaluate climate indicators that are used in impact or adaptation studies. New scientific developments are needed to achieves these goals and the outcome of this TWP will be of direct use to define the innovation and expertise transfer strategy related to the dissemination of key results on climate change and variability.

This requires to:

  •  gather the key analyses and methods used to characterise the uncertainties in the different WPs;
  • develop a common expertise to qualify and quantify the uncertainties considering the different sources of errors inherent to model structure, experimental protocols used to run climate simulations, downscaling strategies or statistical analyses;
  • offer a forum to discuss model evaluation considering both large scale and regional scale simulations, including specific targets on user oriented questions.

In the long term this will provide:

  • A quality assessment of the IPSL climate projections considering large scale and regional simulations (linl with WP2 and WP3, TW1 and TW2)
  • A suite of key diagnostics and examples  to qualify, quantify and understand model uncertainties, including a focus on variables of interest for impact studies and adaptation (all WP and TW1)
  • A documented catalog of methods to assess model results depending of the scientific objectives (WP2, WP4)
  • An analyses of the sources of uncertainties of the suite of climate indicators computed from  climate simulations or from impact models (link with WP4)  that will be distributed and used  to characterize the impact of climate change on the environment of society.