RT5, WP5.2 : Evaluation of processes and phenomena

Objectives : • Analyse the capability of the models to reproduce and predict the major modes of variations in the climate system

• Investigate the nature of the uncertainties due to the clouds and radiations processes

MODEL-DATA18 months : prepare tools

and preliminary report for systematic comparisons

INGV, CNRS-IPSL, DMI, UREADMM

5.2.a) Tropics•ENSO, monsoon

•Intraseasonal variability

5.2.b) Extratropics•Seasonal to decadal variability

•Atlantic-Europe, THC, Storm tracks

5.2.f) Clouds and aerosols•Parametrization scheems

•Analysis of tendency errors•Nudged simulations using ERA40

5.2.c) Global Teleconnections•ENSO-global,

• Monsoon-Mediterranean•Resolution?

•Intraseasonal variation in tropical heating

5.2.d) Feedacks and clouds•Decadal variation of

water vapour,clouds, radiation•Moist/convective and

dry/subsiding tropical regions•Link with surface fluxes

5.2.e) Synthesis• Report of model systematic biases

• Overall assessment of ENSEMBLES models

Systematic errors in the IndoPacific region

1) Analysis of time mean circulation

2) ENSO-Monsoon correlations and

3) The coupling influence in the Pacific and Indian Ocean, using the coupled manifold (Navarra and Tribbia, 2005)

INGV participation to WP5.2

Coupled Manifold in Coupled Simulations

Unfiltered HIGH PASS LOW PASSOBS

T30

T106

SINTEX Model at T30 and T106 resolutions

CGAM contribution to WP5.2:18 Month Plan

• Assess the tropical performance of HadGEM1, particularly ENSO, the Asian Summer Monsoon and their global teleconnections (Julia Slingo, Pete Inness, Buwen Dong, Andy Turner)

• Commence assessment of the sensitivity to resolution (using early test results from HiGEM) of processes and phenomena in the climate system (Warwick Norton, Len Shaffrey)

Indo-Pacific mean climate and variability from Hadley Centre models, HadCM3 and HadCEM

From: Spencer et al. 2004, J. Clim., in press

CGAM contribution to WP5.2:5 Year Plan

• Comparison of seasonal-to-decadal climate variability in the Atlantic-European sector in the ENSEMBLES project coupled model hindcasts and scenario integrations

• Evaluate the mean climate, seasonal cycle and interannual to decadal variability of the tropical Indo-Pacific region, and the ability of the ENSEMBLES models to capture the global teleconnections associated with ENSO and the Indian Summer Monsoon (Example of mean SST errors in Indian Ocean in Hadley Centre models)

• Investigate the influence of model resolution on important aspects of variability in the coupled system

Contibution of IPSL

• Asian monsoon and role of the Indian Ocean

• Interanual and decadal variations of water vapor and clouds (20th century), and link with surface fluxes.

Example : ENSO-Indian ocean

• the 1976-1977 climate regime shift was accompanied by a remarkable change in the lead-lag relationships between Indian Ocean Sea Surface Temperature (SST) and El Niño evolution.

• It has implications for Niño predictions (S-E Indian ocean is now a precursor)

Do models reproduce this?Why? What are the major processes involved?

From Terray

d(CRF)/d(SST) inferred frominterannual variations over 1984-2001

using satellite data (CRF) and meteorological reanalyses (w500 )

d(SW CRF)/d(SST)in circulation regimes

d(LW CRF)/d(SST)in circulation regimes

ISCCP & ERA40ISCCP & NCEP2

ISCCP & ERA40ISCCP & NCEP2

Observed and simulatedd(CRF)/d(SST)

for current climate

d(SW CRF)/d(SST)in circulation regimes

d(LW CRF)/d(SST)in circulation regimes

ISCCP & ERA40ISCCP & NCEP2

Observations 1984-2001IPSL GCM (current climate)

Observations 1984-2001IPSL GCM (current climate)

Contribution of DMI

• Validation of initial model tendencies: nudging-assimilation of ERA40 in model systems

• Estimation of the cause of initial tendency error

Discussion• Possible overlap between INGV, CGAM and

IPSL on Indo Pacific region?• Overlap with WP4.2• Priorities for early report on model biases(link with priorities in other WP?)• Which simulations ? (impossible to look at all

ENSEMBLES simulations) • Deliverables = report. Do we also provide tools

and/or standard diagnosis? Which form?