Comparison between circulation patterns associated to frost events in the humid Pampa in climatic settings related with the experiments CMIP3 and CMIP5 of the GFDL model
Keywords:
temperature extreme events, frost, climate scenarios, GFDL model, Wet PampaAbstract
The purpose of this study is to investigate the change in the atmospheric circulation associated with frost events in the Wet Pampa (WP) in the future climate for the most critical scenarios projected by the GFDL ocean-atmosphere coupled model. Two versions of the GFDL model are used, the GFDL-CM2 for CMIP3 and GFDL-CM3 for CMIP5. We analyze the model capability to simulate the five most extreme cold events in the present climate (1961-1990), with respect to those obtained with the NCEP/NCAR Reanalysis. Then, we compare the future climate simulations (2081-2100) with the model simulation for the present climate.
For the present climate the CMIP3 experiment presents more penetration of the 0°C isotherm in 850 hPa, intensifying the negative temperature anomalies in comparison to the reanalysis. The postfrontal anticyclone is more meridionally extended over the continent, with similar anomalies to those of the reanalysis, mainly over WP. The gradient between the high pressure and the low pressure downwind creates a more intense southerly cold airflow at 850 hPa than the reanalysis, giving place to advective frosts in the studied region. For the future climate, the model projects less penetration of the 0°C isotherm and less intense negative temperature anomalies. The anticyclone maximum is located further north than in the present climate, propitiating radiative frosts. In the upper levels, the subtropical jet shows a more zonally layout and slightly higher intensity than in the present climate simulations.
For the present climate the CMIP5 experiment simulates well the incursion of the 0°C isotherm, although with a more intense temperature anomaly in comparison to the reanalysis. The pressure field presents similar characteristics to those shown in the CMIP3 experiment, but with larger anomalies in the southern part of the continent. For the future scenario, the model projects the 0°C isotherm incursion as well as the negative temperature anomalies similar to the present. The post frontal anticyclone is located further north, overestimating its value and the anomaly over WP. The wind field is similar to the present simulation.
Summarizing the results of both experiments, the future projections with CMIP3 show significant changes with respect to the present, which is not the case with the CMIP5 experiment. These changes are mainly reflected in the pressure field, in which the position of the anticyclone in CMIP3 (CMIP5) would favor radiative (advective) frosts over WP.
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Andrade, K.M., G.V. Müller, I. Cavalcanti, M.E. Fernandez-Long, M. Bidegain, e G.J. Berri, 2012.Avaliação de mudanças na freqüência de sistemas frontais sobre o Sul da America do sul em projeções do clima futuro. Meteorológica, 37, 1, 15-26. http://www.cenamet.org.ar/archivos/Vol37-Nro1-2012.pdf
Cavalcanti I.F.A., G.V. Müller, K. Andrade, and M.E.F. Long, 2013. Cold air intrusions over southeastern South America - GFDL model behavior regarding climate simulations in the 20th century and future projections. Global and Planetary Change, 111, 31-42. doi: https://doi.org/10.1016/j.gloplacha.2013.08.006
Delworth, T.L., et al. 2006. GFDL’s CM2 global coupled climate models-Part 1: Formulation and simulation characteristics, J. Clim.,19, 643–674.
Dunne, John P., et al., 2012. GFDL’s ESM2 Global Coupled Climate–Carbon Earth System Models. Part I: Physical Formulation and Baseline Simulation Characteristics. J. Climate, 25, 6646–6665. doi: http://dx.doi.org/10.1175/JCLI-D-11-00560.1
Fernández-Long M.E., G.V. Müller, A.Beltrán-Przekurat, and O. Scarpati, 2013. Long- and short- term changes in temperature-based agroclimatic indices in Argentina. International Journal of Climatology, 33, 7, 1673–1686.
Kalnay, E., M. Kanamitsu, R. Kistler, W. Collins, D. Deaven, L. Gandin, M. Iredell, S. Sasha, G. White, J. Woollen, Y. Zhu, M. Chelliah, W. Ebisuzaki, W. Higgins, J. Janowlak, K.C. Mo, C. Ropelewski, J. Wang, A. Leetmaa, R. Reynolds, R. Jeene, and D. Joseph, 1996.The NCEP/NCAR 40-year reanalysis project. Bulletin of the American Meteorology Society, 77, 437-471.
Müller, G.V., R. Compagnucci, M.N. Nuñez, and A. Salles, 2003. Spatial analysis of surface circulation associated to frosts in the wet Pampas. International Journal of Climatology, United Kingdom, 23, 943-961.
Müller, G.V., T. Ambrizzi, and M.N. Nuñez, 2005.Mean Atmospheric Circulation leading to Generalized Frosts in Central Southern South America. Theoretical and Applied Climatology, Austria, 82, 95-112.
Müller, G.V. and T. Ambrizzi, 2007.Teleconnection Patterns and Rossby Wave Propagation Associated to Generalized Frosts over Southern South America. Climate Dynamics, 29, 633-645. DOI: https://doi.org/10.1007/s00382-007-0253-x
Müller, G.V. and G.J. Berri, 2007. Atmospheric Circulation Associated with Persistent Generalized Frosts in Central-Southern South America. Monthly Weather Review, 135, 4, 1268–1289.
Müller, G.V. and G.J. Berri, 2012. Atmospheric Circulation Associated with Extreme Generalized Frosts Persistence in Central-Southern South America. Climate Dynamics, 38 (5-6), 837-857. DOI: https://doi.org/10.1007/s00382-011-1113-2
Müller, G.V., C.R.R Repinaldo, K.M Andrade, Cavalcanti I.F.A., 2014. Proyecciones futuras asociada a los eventos extremos frios en el sudeste de Sudamerica sobre la perspectiva del modelo hadcm3. Meteorológica (en revisión).
Skansi, M.L.; M. Brunet, J. Sigró, E. Aguilar, J.A.A. Groening, O.J. Bentancur, C.Y.R. Geier, R.L.C. Amaya, H. Jácome, A.M. Ramos, C.O. Rojas, A.M. Pastén, S.S. Mitro, C.V. Jiménez, R.Martínez, L.V. Alexander, and P.D. Jones, 2013. Warming and wetting signals emerging from analysis of changes in climate extreme indices over South America. Global and Planetary Change, 100, 295–307.
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Copyright (c) 2014 Gabriel. V. Müller, C. R. R. Repinaldo, D. C. Araneo, K. M. Andrade
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