final_program_abstracts[1]

11 IMSC Session Program
Comparing the spatial features of observed and simulated
climate change over the Mediterranean basin
Friday - Parallel Session 6
Aurélien Ribes and Serge Planton
Studies regarding the regional features of climate change have known a growing
interest over the last decades, due to the need for improved projection at such scales.
The main goal of this study is to assess the ability of the climate models to properly
simulate the spatial distribution of anthropogenic climate change at the regional scale,
focusing on the Mediterranean basin. We propose to compare the outputs of a
statistical detection technique applied respectively to climate model runs and observed
data.
In a first step, we introduce briefly the Temporal Optimal Detection (TOD) method
for climate change detection. This method involves looking for a climate change
signal in the observations, assuming that the temporal pattern of change is known. In
addition to assess the significance of the climate change signal, this method allows to
infer the spatial distribution of the change directly, from the observed data.
In a second step, we apply the TOD method to both observed and simulated
temperature datasets covering the 1900-2010 period over the Mediterranean basin.
The climate change signal is significant in all cases and we can compare the evolution
of the test p-value over the period, between observed and modeled climate. In each
case, the method provides an evaluation of the spatial distribution of change. The
main focus of this work is to compare these different spatial patterns, after having
proved their significance. The comparison is done with respect to several metrics,
discussing their respective benefits. In particular, we will illustrate results obtained
with the euclidean metric and the ones given by using the “optimal fingerprint”
metric, often used in detection-attribution studies.
Abstracts 352