A Study of SST-forced Variability and Potential Predictability of Seasonal Mean Fields using the JMA
A Study of SST-forced Variability and Potential Predictability of Seasonal Mean Fields using the JMA
复制标题
使用 JMA 研究海温强迫变率和季节平均场的潜在可预测性
DOI：
10.2151/jmsj1965.75.3_717
复制
发表时间：
1997
影响因子：
3.1
通讯作者：
N. Sato
中科院分区：
文献类型：
--
作者：
M. Sugi;R. Kawamura;N. Sato
利用日本气象厅(JMA)全球模式进行了一次集合气候模拟试验，研究了SST强迫大气变率和季节平均场的潜在可预报性。该乐团由三个模型组成，每个模型集成在同一个34年的时间内。这三次积分使用了1955-1988年期间相同的观测海温，但从不同的大气初始态开始。计算了海温强迫变率与季节平均场总变率的比值。这些比率被认为代表了潜在的可预测性(当SST被完美预测时，可能的最大可预测性)。热带气压场的变异率普遍较高(50-90%)，而温带气压场的变率较低(不到30%)，表明热带气压场的潜在可预报性较高，而温带气压场的潜在可预报性较低。降水的变异率在热带范围内的范围很大，从巴西东北部的74%到印度夏季风的31%，表明热带地区季节平均降雨量的潜在可预报性存在很大的地区差异。全球平均全球陆面平均气温的变异率较高(66%)，而大部分陆地地区的季节平均局地气温的变化率较低(<30%)。这表明，当地地表气温的潜在可预报性较低。
An ensemble climate simulation experiment has been conducted using the Japan Meteorological Agency (JMA) global model to study the SST-forced atmospheric variability and potential predictability of seasonal mean fields. The ensemble consists of three model integrations each for the same 34-year period. The three integrations use the same observed SST for the period 1955-1988 but start from different atmospheric initial states. The variance ratios of the SST-forced variability to the total variability of the seasonal mean fields are computed. The ratios are considered to represent potential predictability (possible maximum predictability when SST is perfectly predicted). The variance ratios of pressure fields are generally high (50-90 %) in the tropics but low (less than 30 %) in the extratropics, suggesting that the potential predictability of the seasonal mean fields is high in the tropics but low in the extratropics. The variance ratios of precipitation take a wide range of values within the tropics from 74 % for N.E. Brazil rainfall to 31 % for Indian summer monsoon rainfall, indicating large regional differences in the potential predictability of seasonal mean rainfall within the tropics. The variance ratio of globally-averaged global mean land surface air temperature is high (66 %) but the ratio is low (less than 30 %) for the seasonal mean local surface air temperature over most land area. This suggests that the potential predictability of local land surface air temperature is low.