Prediction Skill of East Asian Precipitation and Temperature Associated with El Niño in GloSea5 Hindcast Data
Abstract
We investigate the performance of Global Seasonal Forecasting System version 5 (GloSea5) in Korea Meteorological Administration on the relationship between El Niño and East Asian climate for the period of 1991-2010. It is found that the GloSea5 has a great prediction skill of El Niño whose anomaly correlation coefficients of Niño indices are over 0.96 during winter. The eastern Pacific (EP) El Niño and the central Pacific (CP) El Niño are considered and we analyze for EP El Niño, which is well simulated in GloSea5. The analysis period is divided into the developing phase of El Niño summer (JJA(0)), mature phase of El Niño winter (D(0)JF(1)), and decaying phase of El Niño summer (JJA(1)). The GloSea5 simulates the relationship between precipitation and temperature in East Asia and the prediction skill for the East Asian precipitation and temperature varies depending on the El Niño phase. While the precipitation and temperature are simulated well over the equatorial western Pacific region, there are biases in mid-latitude region during the JJA(0) and JJA(1). Because the low level pressure and wind are simulated weakly toward mid-latitude region, though they are similar with observation in low-latitude region. During the D(0)JF(1), the precipitation and temperature patterns analogize with observation in most regions, but there is temperature bias in inland over East Asia. The reason is that the GloSea5 poorly predicts the weakening of Siberian high, even though the shift of Aleutian low is predicted. Overall, the predictability of precipitation and temperature related to El Niño in the GloSea5 is considered to be better in D(0)JF(1) than JJA(0) and JJA(1) and better in ocean than in inland region.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2019
- Bibcode:
- 2019AGUFM.A13I3010L
- Keywords:
-
- 3305 Climate change and variability;
- ATMOSPHERIC PROCESSES;
- 3337 Global climate models;
- ATMOSPHERIC PROCESSES;
- 3362 Stratosphere/troposphere interactions;
- ATMOSPHERIC PROCESSES;
- 0550 Model verification and validation;
- COMPUTATIONAL GEOPHYSICS