Climate change projections for Catalonia (NE Iberian Peninsula). Part I: Regional climate modeling

• A. Barrera-Escoda ^[1] ; J. Cunillera ^[1]
  1. [1] Servei Meteorològic de Catalunya
• Localización: Tethys : revista meteorología y climatología mediterránea, ISSN 1139-3394, Nº. 8, 2011, págs. 75-87
• Idioma: inglés
• Enlaces
  • Texto completo (pdf)
• Dialnet Métricas: 1 Cita
• Resumen

  • This work presents a dynamical technique of climate downscaling to generate projections forthe 21st Century in Catalonia, based on the outputs of the atmosphere-ocean global coupledmodel ECHAM5/MPI-OM. This technique consists in long integrations (5 years) with the MM5mesoscalar model through three one-way nested domains of 135, 45 and 15 km of horizontalresolution and 23 vertical levels. Two possible emission scenarios of the Special Report onEmissions Scenarios are used for the generation of downscaled projections: a severe one (A2)and a moderate one (B1). Only temperature at 2 m and precipitation are studied in detail, asthey are the variables of greatest social interest and the ones that condition the water resourcesmost directly. The general space-time characteristics of these two variables are correctly repro-duced by the methodology used, except for the seasonal cycle of precipitation. The simulationsperformed show a significant cold bias for temperature, as well as a general overestimation ofprecipitation. The scenarios obtained project a sharp increase of temperature (up to 5◦C at theend of the century) and a decrease in the annual mean precipitation during this century, butwith a high spatial and temporal variability. This decrease is sharper during the warm periodof the year (50% in some areas for summer at the end of the century). On the other hand, aslight increase is projected for the greater part of the cold period of the year. Regarding extremevalues, a significant increase of warm months and a slight decrease of cold months is expected.About precipitation, a significant increase of dry periods is projected. However, an increase ofextremely rainy months is also predicted. The projected changes are more marked for the A2scenario than for B1.