A study on the variation in the stratospheric water vapor and the surface area of Polar Stratospheric Clouds of the future atmosphere

点击翻译按钮获取中文摘要

Calculations were performed by a 1-D chemistry-radiation coupled model in order to study the effects of sulfuric aerosols increased by a volcanic eruption on climate. The size distribution of the sulfuric aerosols was assumed in the calculation based on the lidar and balloon observations. The surface area was calculated from the size distribution. It is found that the ozone decrease due. to the heterogeneous reactions on the sulfuric aerosols accelerates the temperature recovery from the warming due to the absorption of the infrared radiation by the aerosols. We included the sulfate chemistry into the CCSR/NIES chemical climate model (CCM) and successfully simulated the 3-dimensional (3-D) distribution of sulfuric aerosols. A 3-D nudging chemical transport model (CTM) was also developed from the CCSR/NIES CCM and used to investigate the low total ozone values less than 220 DU in the subtropical Western Pacific in winter. The results show that the effect of heterogeneous reactions on ICE and NAT particles on the ozone amount is about 2-3 DU, which is smaller than the ozone variation due to QBO (around 5 DU), but not negligible. The low ozone amount in this region should be monitored carefully in the future.A CTM calculation was performed with stratospheric water vapor amounts increased artificially by 1 ppmv to investigate the water vapor effect on Ozone Hole in the future atmosphere. We could not find any dramatic change in the ozone hole of the model. Although the size distribution and the refractive index of the aerosols were assumed based on observations for this calculation, it is not necessarily true that these parameters are also acceptable for the future atmosphere. A correct knowledge of the water vapor effect on ozone depletion in the future atmosphere will not be obtained until the mechanisms of water vapor transport are correctly understood.