东亚地区春季二氧化硫的输送与转化过程研究 I.模式及其验证

结合新近评估的东亚地区污染源资料 ,作者利用一个耦合的区域化学输送模式系统以探讨东亚地区春季期间气象过程、气相与液相化学过程、非均相化学过程、气溶胶过程和干湿沉降过程对二氧化硫输送及转化过程的影响 ,并研究二氧化硫和硫酸盐气溶胶的空间分布及变化特征。模拟的二氧化硫和硫酸盐气溶胶的浓度值与 2 0 0 1年春季飞机和地面获取的观测值进行了比较。比较结果显示 ,模拟值与观测值具有很好的一致性 ,模式系统很好地反映了二氧化硫和硫酸盐气溶胶的分布特征和变化规律 ,再现了许多观测到的重要特征 。

东亚地区春季黑碳气溶胶源排放及其浓度分布

本研究收集整理了东亚地区一个黑碳气溶胶的排放源 ,并利用一个三维化学输送模式系统模拟研究了东亚地区春季黑碳气溶胶的输送和演变过程 .黑碳气溶胶浓度的模拟值与地面观测站和观测船获取的监测值相比 ,模拟值与监测值具有良好的一致性 .这表明本研究收集整理的黑碳气溶胶的排放量及其分布是基本合理的 ,模式系统较好地反映了黑碳气溶胶浓度的时空分布和变化趋势 ,再现了许多观测到的重要特征 .模拟结果表明 ,东亚地区春季间隙性的长距离输送对于西北太平洋海域的黑碳气溶胶浓度分布具有非常重要的影响 .

东亚地区春季硫氧化物浓度分布及其收支研究

利用一个耦合的区域化学输送模式系统，模拟了2001年3～4月间东亚区域二氧化硫（SO2）和硫酸盐（SO4^2-）气溶胶浓度的时空分布，并分析了它们的来源、输送、转化和沉降过程在浓度形成中的作用。为了检验模拟结果的合理性，侧重分析了4月9～12日SO2的输送和转化过程。在这一期间，SO2浓度观测资料显示，日本的观测站Happo、Oki和Hedo周围及日本海部分海域先后经历了一次SO2浓度高值。模拟结果表明，日本东京附近的三宅岛火山喷发严重影响了日本列岛和周边海域SO2和SO4^2-气溶胶的分布，是引起观测站周围及日本海部分海域SO2浓度高值的主要原因。3月1日至4月31日间的硫收支分析显示，气相与液相化学过程在SO2的氧化过程中具有同等的重要性，模拟区域排放的硫氧化物中有约42％（其中约25％为SO2）被输送到模拟区域以外，约57％（约35％为湿沉降）沉积在模拟区域内。

东亚地区春季有机碳气溶胶分布特征的初步研究

本研究利用一个区域三维化学输送模式模拟研究了东亚地区2001年春季有机碳气溶胶的输送与演变过程.有机碳气溶胶浓度的模拟值与TRACE-P和ACE-Asia观测期间获取的观测值相比,模拟值与观测值之间具有非常好的一致性,模式合理地反映了有机碳气溶胶浓度的时空分布.模拟结果表明,有机碳气溶胶柱含量的高值区(大于16 mg/m2)主要集中在长江中游和西南地区,黄河以南的我国大部分地区柱含量超过了7 mg/m2,并且4 mg/m2的等值线延伸到了西北太平洋深处.

A comparison of atmospheric CO_2 concentration GOSAT-based observations and model simulations

Satellite observations of atmospheric CO2 are able to truly capture the variation of global and regional CO2 concentration.The model simulations based on atmospheric transport models can also assess variations of atmospheric CO2 concentrations in a continuous space and time,which is one of approaches for qualitatively and quantitatively studying the atmospheric transport mechanism and spatio-temporal variation of atmospheric CO2 in a global scale.Satellite observations and model simulations of CO2 offer us two different approaches to understand the atmospheric CO2.However,the difference between them has not been comprehensively compared and assessed for revealing the global and regional features of atmospheric CO2.In this study,we compared and assessed the spatio-temporal variation of atmospheric CO2 using two datasets of the column-averaged dry air mole fractions of atmospheric CO2(XCO2)in a year from June 2009 to May 2010,respectively from GOSAT retrievals(V02.xx)and from Goddard Earth Observing System-Chemistry(GEOS-Chem),which is a global 3-D chemistry transport model.In addition to the global comparison,we further compared and analyzed the difference of CO2 between the China land region and the United States(US)land region from two datasets,and demonstrated the reasonability and uncertainty of satellite observations and model simulations.The results show that the XCO2 retrieved from GOSAT is globally lower than GEOS-Chem model simulation by 2 ppm on average,which is close to the validation conclusion for GOSAT by ground measures.This difference of XCO2 between the two datasets,however,changes with the different regions.In China land region,the difference is large,from 0.6 to 5.6 ppm,whereas it is 1.6 to 3.7 ppm in the global land region and 1.4 to 2.7 ppm in the US land region.The goodness of fit test between the two datasets is 0.81 in the US land region,which is higher than that in the global land region(0.67)and China land region(0.68).The analysis results further indicate that the inconsistency of CO2concentration between satellite observations and model simulations in China is larger than that in the US and the globe.This inconsistency is related to the GOSAT retrieval error of CO2 caused by the interference among input parameters of satellite retrieval algorithm,and the uncertainty of driving parameters in GEOS-Chem model.