Author(s): Chi Hang Chung; Ji Chen
Linked Author(s): Ji Chen
Keywords: Global precipitation anomaly; Climate patterns; A four-index model; Teleconnection
Abstract: This study verifies the performance of the four climate index model for simulating precipitation anomaly around the world. Since the relationship between the climate patterns and the precipitation anomaly is seasonal dependent, the model may have varying performance in different months. This study uses the global precipitation data obtained from the Global Precipitation Climatology Project (GPCP), and the study period is from 1979 to 2011. The correlation result shows that the climate patterns have strong impact on the precipitation for the regions that have significant correlation with the climate patterns. This is meaningful because when the precipitation is significantly influenced by the climate patterns, the precipitation will depends on the climate patterns, and using the climate pattern indexes to forecast precipitation anomaly is possible. This study follows the previous study, which uses the four climate indexes (ENSO, IOD, AO and AAO) to simulate precipitation anomaly, to confirm the performance of the four climate index model. The goal of the study is to evaluate the performance of the prediction of extreme precipitation events. Using the observed extreme precipitation data, we examine the predictability of the four climate index model and the causes of the extreme events are also studied to understand how they are related to the key climate patterns. The improvement on the predictability of the regional precipitations by using the four climate index model instead of the dominant climate pattern is also studied. The physical mechanisms of causing such differences in the predictability of the regional precipitation are also explored. Overall, this study can be useful for further investigation of the teleconnection between the climate patterns and climate variations.