INVESTIGADORES
RUIZ Juan Jose
artículos
Título:
Comparison of methods to generate probabilistic quantitative precipitation
Autor/es:
JUAN RUIZ, CELESTE SAULO Y EUGENIA KALNAY
Revista:
Weather and Forecasting
Editorial:
American Meteorological Society
Referencias:
Lugar: Boston; Año: 2008 vol. 24 p. 319 - 336
Resumen:
In this work, the quality of several Probabilistic Quantitative Precipitation Forecasts (PQPF) is
examined. The analysis is focused over South America during a two month period in the warm season.
Several ways to generate and calibrate the PQPF have been tested, using different ensemble systems
and single model runs. Two alternative calibration techniques (static and dynamic) have been tested.
To take into account different precipitation regimes, PQPF performance has been evaluated
over two regions: the northern part of South America, characterized by a tropical regime and the
southern part, where synoptic scale forcing is stronger. The results support the adoption of such area
separation, since differences in the precipitation regimes produce significant differences in PQPF
performance.
The more skillful PQPF are the ones obtained after calibration. PQPF derived from the
ensemble mean also show higher skill and better reliability than those derived from the single ensemble
members. The performance of the PQPF derived from both ensemble systems is similar over the
southern part of the region; however, over the northern part the super ensemble approach seems to
achieve better results in both reliability and skill.
Finally, the impact of using CMORPH estimates to calibrate the precipitation forecast has been
explored since the more extensive coverage of this dataset would allow its use over areas where the
rain gauge coverage is insufficient. Results suggest that systematic biases present in the CMORPH
estimates produce only a slight degradation of the resulting PQPF.