A high-resolution 43-year atmospheric hindcast for South America generated with the MPI regional model.

SILVESTRI, GABRIEL; VERA, CAROLINA; JACOB, DANIELA; PFEIFER, SUSANA; TEICHMANN, CLAUS

CLIMATE DYNAMICS

Springer-Verlag

Lugar: Berlin; Año: 2008 p. 1 - 38

0930-7575

An evaluation of the present-day climate in South America simulated by the MPI atmospheric limited area model, REMO, is made. The model dataset was generated by dynamical downscaling from the ECMWF-ERA40 reanalysis and compared to in-situ observations. The model is able to reproduce the low-level summer monsoon circulation but it has some deficiencies to represent the South American Low-Level Jet structure. At upper levels, summer circulation features like the Bolivian High and the associated subtropical jet are well simulated by the model. Sea-level pressure fields are in general well represented by REMO. The model exhibits reasonable skill in representing the general features of the mean seasonal cycle of precipitation. Nevertheless, there is a systematic overestimation of precipitation at both tropical and subtropical regions. Differences between observed and modeled temperature are smaller than 1.5°C over most of the continent, excepting during spring when those differences are quite large. Results show that the dynamical downscaling performed using REMO introduces enhancement of the global reanalysis specially in temperature at the tropical regions during the warm season and in precipitation at both the subtropics and extratropics. These results suggest that REMO can be a useful tool for regional downscaling of global simulations of present and future climates.