A contemporary seasonal forecasting system is used to study the impacts of a volcanic sulfate injection into the stratosphere on the seasonal forecasts for surface temperatures, the El Niño Southern Oscillation (ENSO), and precipitation. The focus is a case study of the June 1991 eruption of Mt. Pinatubo, Philippines and the period from July 1991 to February 1992. Version 2 of the Goddard Earth Observing System (GEOS) subseasonal-to-seasonal (S2S) forecasting system is used in this study. GEOS-S2S includes the GOddard Chemistry, Aerosols, Radiation and Transport (GOCART) aerosol module, which allows to prognostically simulate aerosol distributions. GOCART is coupled to the radiation and cloud modules to include the impact of the eruption on forecasted radiation and precipitation. The coupled GEOS-S2S system was initialized in May 1991 with fields based on observations to produce ten-member 9-month forecasts with and without the volcanic sulfur injection. The results of these ensemble experiments demonstrate that including Mt. Pinatubo in seasonal forecasts would improve the forecasts of the 1991–1992 global mean temperature and precipitation but worsen the forecast of ENSO by strengthening of El Niño beyond what showed in observations. Most significant changes in the forecasts of temperatures and precipitation are limited to the tropics. The only land area where the inclusion of Pinatubo significantly lowered the forecasted precipitation is tropical Africa.

中文翻译：

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皮纳图博火山喷发对地表温度和美国宇航局 GEOS 次季节到季节系统降水预报的影响

现代季节性预报系统用于研究火山硫酸盐注入平流层对地表温度、厄尔尼诺南方涛动 (ENSO) 和降水的季节性预报的影响。重点是 1991 年 6 月菲律宾皮纳图博火山喷发和 1991 年 7 月至 1992 年 2 月期间的案例研究。使用戈达德地球观测系统 (GEOS) 次季节到季节 (S2S) 预测系统的第 2 版在这个研究中。GEOS-S2S 包括 GOddard 化学、气溶胶、辐射和传输 (GOCART) 气溶胶模块，它允许预测性地模拟气溶胶分布。GOCART 与辐射和云模块耦合，以包括喷发对预测辐射和降水的影响。耦合 GEOS-S2S 系统于 1991 年 5 月使用基于观测的油田进行初始化，以产生 10 个成员的 9 个月预测，包括火山硫注入和不注入。这些集合实验的结果表明，将皮纳图博山纳入季节性预报将改善对 1991-1992 年全球平均温度和降水的预报，但由于厄尔尼诺现象的加强超出观测结果，使 ENSO 的预报恶化。温度和降水预报的最显着变化仅限于热带地区。将皮纳图博包括在内的唯一一个显着降低预测降水量的陆地区域是热带非洲。这些集合实验的结果表明，将皮纳图博山纳入季节性预报将改善对 1991-1992 年全球平均温度和降水的预报，但由于厄尔尼诺现象的加强超出观测结果，使 ENSO 的预报恶化。温度和降水预报的最显着变化仅限于热带地区。将皮纳图博包括在内的唯一一个显着降低预测降水量的陆地区域是热带非洲。这些集合实验的结果表明，将皮纳图博山纳入季节性预报将改善对 1991-1992 年全球平均温度和降水的预报，但由于厄尔尼诺现象的加强超出观测结果，使 ENSO 的预报恶化。温度和降水预报的最显着变化仅限于热带地区。将皮纳图博包括在内的唯一一个显着降低预测降水量的陆地区域是热带非洲。