Joint Seminar: Improving confidence in precipitation projections for future climate

An ensemble of regional climate modelling simulations from the European

framework project PRUDENCE are compared across European sub-regions with

observed daily precipitation from the European Climate Assessment

dataset by characterising precipitation in terms of probability density

functions (PDFs). Models that robustly describe the observations for the

control period (1961–1990) in given regions as well as across regions

are identified, based on the overlap of normalised PDFs, and then

validated, using a method based on bootstrapping with replacement. We

also compare the difference between the scenario period (2071–2100) and

the control period precipitation using the best models obtained. By

using a metric quantifying the deviation over the entire PDF, we find a

clearly marked increase in the contribution to the total precipitation

from the more intensive events in the scenario period almost everywhere.

This change is tested to be robust and is found in all models and in all

sub-regions. We demonstrate that there is a detectable increased scaling

with increased warming, making the increase in PDF difference a relative

indicator of climate change level. Furthermore, the crossover point

separating decreasing from increasing contributions to the normalized

precipitation spectrum when subtracting the control period PDF from the

scenario period PDF does not show any significant change, which is in

accordance with expectations from a simple analytical fit to the

precipitation spectrum.

Datum

07.05.2008

Uhrzeit

15:15 Uhr

Ort

Bundesstr. 53, room 022/023
Seminar Room 022/023, Ground Floor, Bundesstrasse 53, 20146 Hamburg, Hamburg

ReferentIn

Peter Berg, DMI, Kopenhagen

Chair


Zur Übersicht