Climate change scenarios - WP2000

Partners involved: MPI (lead contractor), LMD, DMI, CNRM, the Met Office

The aim of this work package is yo diagnose the future impacts of anthropogenic climate change on monsoon climates using existing control/scenario integrations. The application of regional models to monsoon systems will be included since they provide the higher spatial resolution needed for the impact studies involving agriculture and hydrology. The incidence of extreme events will be a particular focus of study.

Key achievements so far:

• a new climate scenario experiment covering the 21st century has been performed using the latest version of the coupled atmosphere-ocean-sea ice model developed at CNRM. The control simulation was fairly realistic. The main changes between the 1970-2000 and 2070-2100 periods were a strong increase in the ITCZ rainbelt associated with lower precipitaiton in the winter hemisphere subtropics and an increase in monsoon rainfall over the Sahel and India.

• the climate response over Africa for the periods 1980-2010, 2040-2070 and 2070-2100 have been analysed in detail. The warming is larger over the continents and the increase in the land-sea contrast leads to a strengthening of the hydrologic cycle nd of the monsoon circultaion.

• time-slice experiments covering two periods: 1970-2000 and 2060-2089 (when the carbon dioxide content of the atmosphere is predicted to double) show that the increased land-sea temperature contrast in the Indian Ocean basin leads to a strengthening of the monsoon circulation

• further time-slice experiments with a sophisticated land-surface scheme show that the simulated increase of rainfall over South India is not clearly correlated with the wind field changes and that the land surface scheme has an significant effect on the simulation of the monsoon

• a transient greenhouse gas warming integration again show that increases of greenhouse gas concentrations intensify the Asian summer monsoon and its variability

• changes the intrasesasonal variability of the Asian monsoon was studied by comparing model integrations with pre-industrial carbon dioxide with those with increased carbon dioxide. In the warmer future climate, the change in intraseasonal precipitation anomalies can be attributed to the change in the frequency of cyclones originating in the Bay of Bengal.

Publications on this topic arising from PROMISE

Ashrit R.G., H. Douville, K. Rupa Kumar, J.F. Royer, F. Chauvin 2003 Response of the Indian Monsoon and ENSO-monsoon teleconnection to enhanced greenhouse effect in transient simulations of the CNRM coupled model J. Meteorol. Soc. Japan Submitted

Garric G., H. Douville, M. Déqué 2002 Prospects for improved seasonal predictions of monsoon precipitation over Sahel International Journal of Climatology 22 331-345

Hu, Z.-Z., M. Latif, E. Roeckner, and L. Bengtsson 2000 Intensified Asian summer monsoon and its variability in a coupled model forced by increasing greenhouse gas concentrations Geophys. Res. Letters 27 2681-2684

May W 2003 Mechanisms of the predicted future changes in the Indian summer monsoon due to greenhouse warming Climate Dynamics in preparation

May W., Roeckner E. 2001 A time-slice experiment with the ECHAM4 AGCM at high resolution: the impact of horizontal resolution on annual mean climate change Climate Dynamics 17 407-420

May W. 2002 Simulated changes of the Indian summer monsoon under enhanced greenhouse gas conditions in a global time-slice experiment Geophys. Res. Lett. 29 1029

Maynard K., J.F. Royer, F. Chauvin 2002 Impact of greenhouse warming on the West African summer monsoon Climate Dynamics 19 499-514

Royer J.F., D. Cariolle, F. Chauvin, M. Déqué, H. Douville, R.M. Hu, S. Planton, A. Rascol, J.L. Ricard, D. Salas y Mélia, F. Sevault, P. Simon, S. Somot, S. Tyteca, L. Terray, S. Valcke 2002 Simulation des changements climatiques au cours du 21-ème siècle incluant l'ozone stratosphérique (Simulation of climate changes during the 21-st century including stratospheric ozone). Comptes Rendus de Geoscience 334 147-154

Publications on this topic by PROMISE partners

Martin, G.M. (2001) K. Arpe, F. Chauvin, L. Ferranti, K. Maynard, J. Polcher, D.B. Stephenson, P. Tschuck (2001) Simulation of the Asian Summer Monsoon in Five European General Circulation Models. Atmospheric Science Letters DOI:10.1006/asle.2000.000

Martin, G.M. 1999. The simulation of the Asian Summer Monsoon, and its sensitivity to horizontal resolution, in the UK Meteorological Office Unified Model. Q. J. R. Meteorol. Soc., 125 1499-1525

Martin, G.M. and Soman, M.K. 2000. Effects of changing physical parametrisations on the simulation of the Asian summer monsoon in the UK Meteorological Office Unified Model. Hadley Centre Technical Note No. 17 Available from The Met. Office, London Road, Bracknell, RG12 2SY, U.K. and online

Polcher, J. (1994) Etude de la sensibilite du climat tropical a la deforestation. PhD Thesis, Universite Pierre et Marie Curie, Paris VI.

Polcher, J. and Laval, K. (1994a) The impact of African and Amazonian deforestation on tropical climate. Journal of Hydrology 155:389-405.

Polcher, J. and Laval, K. (1994b) A statistical study of the regional impact of deforestation on climate in the LMD-GCM. Climate Dynamics 10:205-219.

Le Roux, X., Polcher, J., Dedieu, G., Menaut, J. C., and Monteny, B. (1994) Radiation exchanges above west african moist savannas: seasonal patterns, and comparaison with a GCM simulation. J. Geophys. Res. 99(D12):25,857-25,868.

Mechoso, C.R., Robertson, A.W., Barth, N., Davey, M.K., Delecluse, P., Gent, P.R., Ineson, S., Kirtman, B., Latif, M., Le Treut, H., Nagai, T., Neelin, J.D., Philander, S.G.H., Polcher, J., Schopf, P.S., Stockdale, T., Suarez, M.J., Terry, L., Thual, O., Tribbia, J.J. (1995). The seasonal cycle over the tropical pacific in general circulation models. Monthly Weather Review 123(9):2825-2838.

Polcher, J. (1995) Sensitivity of tropical convection to land surface processes. Journal of the Atmospheric Sciences 52(17):3143-3161.

R.C. Raghava, K. Laval, R. Sadourny, J. Polcher (1995) On the atmospheric response to the tropical denuding of vegetation. Atmospheric Environment 29, pp1963-2000.

K. Laval and J. Polcher (1995) Sensitivity of the Indian Monsoon to Land-Surface Evaporationrate in the LMD-GCM. AMIP Scientific Conference, 15-19 May 1995, Monterey, California

Polcher J., Laval, K., Dumenil, L., Lean, J., Rowntree, P.R. (1996) Comparing three land surface schemes used in GCMs. Journal of Hydrology 180:373-394.

Polcher J. and Shao, Y. (1996) A Standard format for reporting PILPS experiments. Global and Planetary Change 13:217-223.

Peylin, P., Polcher J., Bonan, G., Williamson, D., Laval, K. (1996) Comparison of two complex Land-Surface Schemes coupled to the NCAR-GCM J. Geophys. Res. 102:19,413-19,431.

Chen, T.H. ... Polcher, J. ... Laval, K. ... (1996) Cabauw experimental results from the project for intercomparison of land-surface parameterization schemes (PILPS) Journal of Climate 10:1194-1215.

Laval, K., Raghava, R.C., Polcher, J., Sadourny, R., Forichon, M., (1996) Simulation of the 1987 and 1988 Indian Monsooons using the LMD GCM. Journal of Climate 9:3357-3371.

Henderson-Sellers, A., Polcher, J., Chen, T. H., Nakken, M., and Pitman, A. J., (1996) Predicting global change at the land-surface: the Project for Intercomparison of Land-Surface Parameterization Schemes (PILPS) (Phase 4). Seventh Symposium on Global Change Studies pp. 59-66, Boston, American Meteorological Society.

Polcher, Jan (1997) The sensitivity of the tropical climate to land surface processes. ECMWF Seminar 8 Sep. 1997 - 12 Sep. 1997

Laval,Katia (1997) Hydrological processes in GCMs. NATO ASI Series Vol 46. Edited by Sorooshian. Springer Verlag.

Schulz, J.-P., L. Dumenil, J. Polcher, C. A. Schlosser, Y. Xue, (1998) Land surface energy and moisture fluxes: comparing three models, J. Appl. Meteor. 37:288-307.

Ducharne, A. Laval, K. and Polcher, J. (1998) Sensitivity of the hydrological cycle to the parameterization of soil hydrology in a GCM. Climate Dynamics, 14, pp 307-327.

J.Polcher, B. McAvaney, P. Viterbo, M.-A. Gaertner, A. Hahmann, J.-F. Mahfouf, J. Noilhan, T. Phillips, A. Pitman, C.A. Schlosser, J.-P. Schulz, B. Timbal, D. Verseghy and Y. Xue. (1998) A proposal for a general interface between land-surface schemes and general circulation models. Global and Planetary Change 19, pp 263-278

Ciret, C., Polcher, J. and Le Roux, X. (1998) An approach to simulate the phenology of savanna ecosystems in the LMD general circulation model. Global Biogeochemical Cycles 13(2), pp603-622

De Rosnay, P. and Polcher J. (1998) Modeling root water uptake in a complex land surface scheme coupled to a GCM. Hydrology and Earth System Sciences 2(2-3), pp239-256

J. Polcher, J. Crossley, C. Bunton, H. Douville, N. Gedney, K. Laval, S. Planton, P.R. Rowntree, and P. Valdes (1998) Importance of land-surface processes for the uncertainties of climate change; A European project. GEWEX-News, May.

M. Sabre, K. Hodges, K. Laval, J. Polcher and F. Desalmand (2000): Simulations of Monsoon disturbances in the LMD GCM. Monthly Weather Review, 128, 3752-3771

A. Ducharne and K. Laval (2000): Influence of the realistic description of soil-holding capacity on the global water cycle in a GCM. Journal of Climate, 13, 4393-4413

Further information

see:
Work package description in the proposal
First annual report (available to PROMISE partners or with the permission of the lead contractor)
Second annual report (available to PROMISE partners or with the permission of the lead contractor)
Third annual report (available to PROMISE partners or with the permission of the lead contractor)
Final report

or:

contact Emily Black (emily@met.reading.ac.uk)