EUropean CLimate and weather Events: Interpretation and Attribution Peter Stott Met Office Hadley Centre peter.stott@metoffice.gov.uk

EUCLEIA EUropean CLimate and weather Events: Interpretation and Attribution Started January 2014 EUCLEIA: 3 year project under the FP7-SPACE Call, that brings together 11 European partners with an outstanding scientific profile in climate research: The project aims to develop a quasi-operational attribution system, well calibrated on a set of test cases for European extreme weather, that will provide to targeted groups of users, well verified, well understood assessments on the extent to which certain weather-related risks have changed due to human influences on climate. TEST CASES: Heat waves Cold spells Droughts Floods Storm surges © Crown copyright Met Office

Near-real time attribution service ETHZ UEDIN IC3 DMI Reading Univ HZG KNMI CNRS UVSQ UOxf Met Office WP3 (Pete Walton, Oxford) Stakeholder User Panel WP4 (Hans von Storch, HZG) Stakeholder Engagement WP5 (Myles Allen, Oxford) Methodologies / Framing Issues WP6 (Robert Vautard, CNRS CEA) Evaluation & Diagnostics WP7 (Geert Jan van Oldenborgh, KNMI) Targeted Test Cases WP8 (Nikos Christidis, Met Office) Near-real time attribution service © Crown copyright Met Office

Objectives Derive requirements from targeted user groups Develop methods for event attribution including development of experimental designs and clear ways of framing Identify key processes driving extreme events and develop methodologies for representing level of confidence in attribution results Demonstrate the utility of the attribution system on a set of test cases of European weather and climate extremes Deliver quasi-operational attribution assessments on a range of timescales in the aftermath of extreme events © Crown copyright Met Office

Highlights of work so far Substantial input to BAMS annual reports explaining extreme events of previous year from a climate perspective 10 out of 34 papers submitted to 2015 edition involving EUCLEIA input Significant contribution to capacity building through editorship, IDAG, ACE User perspectives much better understood (WP3, WP4) In depth studies of Paris and Baltic Sea region stakeholders (D4.2) Understanding of wider stakeholder needs (D3.4) A key component of project in its pre-operational phase is to test developing capability to assess specific weather and climate events (WP7) UK temperatures 2014 (Fast track) UK stormy winter 2013/14 (Targetted)

Highlights of work so far Development of observational basis (WP6) Understanding of observational requirements (D6.1) Development of observational indices Development of methodology for assessing robustness of attribution assessments (WP6; D6.5, MS6, MS7) Two papers submitted to peer-reviewed publications concerning quantifying reliability of attribution results (Bellprat et al, Lott and Stott) Evaluation of mechanisms for temperature extremes in Europe(Kreuger et al, 2015) Prototype quasi-operational attribution modelling system developed (WP8, MS10) 60km resolution HadGEM3-A model Supplemented with fast-track methods Successful General Assembly Held in Paris during Our Common Future Conference Substantial contribution to Attribution of Extremes session at Our Common Future For development of observations, extension of ERA-interim with operational analyses, new hydrological dataset, new stratospheric warming indices