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THE IMPACT OF RELATIVE HUMIDITY ON THE RADIATIVE PROPERTY AND RADIATIVE FORCING OF SULFATE AEROSOL* 
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下载免费PDF全文 With the data of complex refractive index of sulfate aerosol,the radiative properties of the aerosol under 8 relative humidity conditions are calculated in this paper.By using the concentration distribution from two CTM models and LASG GOALS/AGCM,the radiative forcing due to hygroscopic sulfate aerosol is simulated.The results show that:(1)With the increase of relative humidity,the mass extinction coefficiency factor decreases in the shortwave spectrum;single scattering albedo keeps unchanged except for a little increase in longwave spectrum,and asymmetry factor increases in whole spectrum.(2)Larger differences occur in radiative forcingsimulated by using two CTM data,and the global mean forcing is -0.268 and -0.816 W/m2,respectively.(3)When the impact of relative humidity on radiative property is taken into account,the distribution pattern of radiative forcing due to the wet particles is very similar to that of dry sulfate,but the forcing value decreases by 60%. 相似文献
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青藏高原地气系统云辐射强迫的气候学特征 总被引：6，自引：2，他引：6
利用ＥＲＢＥ－Ｓ４和ＩＳＣＣＰ－Ｃ２月平均资料着重分析了青藏高原这一特殊气候区域地气系统云辐射强拓的气候学特征，分析结果表明，冬，夏季云对气系统辐射强迫的场分布形势有明显的差异，对于地气系统长波辐射，冬季高原主体云强迫高值区，夏季云强迫空间变化平缓，高原主体平均云的温室效应春季最大，秋季最小，云使地气系统射出长波辐射年平均减少４５．６Ｗ／ｍ＾２对于地气系统短波辐射，冬季高原地区云强迫相对高值区，夏 相似文献
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黑河地区大气沙尘对地面辐射能收支的影响 总被引：29，自引：16，他引：13
利用１９９１年２月下旬至５月中旬ＨＥＩＦＥ张掖绿洲和沙漠站大气浑浊度观测和地面辐射平衡各个分量观测资料,分析和估算了大气沙尘对地面辐射能收支的影响,晴天大气透过率和达地面的短波辐射与大气浑浊度系数有产好的负相关,大气军浊系数增大时透过率和地面总辐射减少,大气浑浊度系数增大０．１,地面总辐射减少１．３％～１．９％,４月大气浑浊度由０．１增大到０．６,正午时刻地面总辐射减少６７．６～８５．８Ｗ／ｍ＾２ 相似文献
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In this paper,the RIEMS 2.0 model,source emission in 2006 and 2010 are used to simulate the distributions and radiative effects of different anthropogenic aerosols over China.The comparison between the results forced by source emissions in 2006 and 2010 also reveals the sensitivity of the radiative effects to source emission.The results are shown as follows:(1) Compared with those in 2006,the annual average surface concentration of sulfate in 2010 decreased over central and eastern China with a range of-5 to 0 μg/m~3;the decrease of annual average aerosol optical depth of sulfate over East China varied from 0.04 to 0.08;the annual average surface concentrations of BC,OC and nitrate increased over central and eastern China with maximums of 10.90,11.52 and 12.50μg/m~3,respectively;the annual aerosol optical depths of BC,OC and nitrate increased over some areas of East China with extremes of 0.006,0.007 and 0.008,respectively.(2)For the regional average results in 2010,the radiative forcings of sulfate,BC,OC,nitrate and their total net radiative forcing at the top of the atmosphere over central and eastern China were-0.64,0.29,-0.41,-0.33 and-1.1 W/m~2,respectively.Compared with those in 2006,the radiative forcings of BC and OC in 2010 were both enhanced,while that of sulfate and the net radiative forcing were both weakened over East China mostly.(3)The reduction of the cooling effect of sulfate in 2010 produced a warmer surface air temperature over central and eastern China;the maximum value was 0.25 K.The cooling effect of nitrate was also slightly weakened.The warming effect of BC was enhanced over most of the areas in China,while the cooling effect of OC was enhanced over the similar area,particularly the area between Yangtze and Huanghe Rivers.The net radiative effect of the four anthropogenic aerosols generated the annual average reduction and the maximum reduction were-0.096 and-0.285 K,respectively,for the surface temperature in 2006,while in 2010 they were-0.063 and-0.256 K,respectively.In summary,the change in source emission lowered the cooling effect of anthropogenic aerosols,mainly because of the enhanced warming effect of BC and weakened cooling effect of scattering aerosols. 相似文献
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The characteristics of atmospheric aerosols in the Golmud desert over the Tibetan (Qinghai-Xizang) Plateau are investigated using the measurements made during the QXPMEX-79.Using spectroscopic observations at the surface and satellite data,the aerosol optical depth is calculated,from which the aerosol size distribution is worked out by means of an inversion method.The effects of vertical distribution of aerosols on irradiance and heating rate profiles are investigated using radiation models in conjunction with the assumption of three idealized aerosol profiles.The effect of aerosols on solar irradiance at the surface is also investigated and the results are compared with the observations.It is shown that the solar irradiance can be reduced by up to 100 W m-2 in the presence of aerosols,and the heating rate can be increased by 1 Kd-1. 相似文献
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青藏高原地区大气辐射加热场的季节变化 总被引：5，自引：1，他引：5
本文利用美国犹他大学系新近发展的辐射和云参数化模式对青藏高原地区甘孜、那曲、拉萨三站及东部平原地区的南京１９８２年８月－１９８３年７月的辐通量和大气加热率进行了计算，分析研究了高原地区大气辐射场的季节变化特征及其与气候的关系，并对一些主要的影响因子进行了简要的讨论。 相似文献
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利用MODIS-GOCART气溶胶资料研究中国东部地区气溶胶直接辐射强迫 总被引：3，自引：0，他引：3
利用MODIS-GOCART同化的2001年逐月气溶胶光学厚度资料，在修改区域气候模式RegCM2辐射方案的基础上，连续积分5年获得平均的中国东部地区气溶胶短波和长波直接辐射效应，并通过数值试验研究了气溶胶垂直分布对辐射强迫及其气候响应的影响。结果表明：气溶胶的短波辐射效应能冷却地表、加热大气；长波辐射效应能加热地表、冷却大气；大气顶净辐射强迫年平均为-4．1W／m^2；辐射强迫绝对值在春季最大，夏季次之，冬季最小；模拟区域中最大辐射强迫值主要位于华北、华南地区及四川盆地；气溶胶垂直分布是影响气溶胶辐射强迫的重要因素。总体上气溶胶层越靠近地面，大气顶辐射强迫绝对值越大，地表辐射强迫绝对值越小，大气顶辐射强迫对垂直分布较敏感；气候系统的反馈作用会放大气溶胶垂直分布对辐射气候效应的影响。 相似文献
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In this paper satellite-derived radiative energy budget such as shortwave radiative heating,longwaveradiative heating and net radiation balance have been studied for the onset phase of summer monsoon1979. Since cloud play an important role in determining diabatic heating field as well as being a reflectionof status of the monsoon itself, the day to day evolution of clouds from TIROS-N satellite has beenmade. Satellite-derived radiative heating rates from surface to 100 hPa were computed for each 100 hPathickness layer. These heating rates were then compared with the observed latitudinal distribution of total radintive heating rates over the domain of the study. From the results of our study it was found thatthe characteristic features such as net radiative heating rates of the order of 0.2℃/day at upper tropospheric level(100-200 hPa)and cooling throughout the lower tropospheric layers with relatively lesscooling between 500-700 hPa layer observed.in a case of satellitexierived radiative energy budget agreewell with the characteristic features of observational radiative energy budget over the domain of thestudy. Therefore, it is suggested that radiative energy budget derived from satellite observati0ns be usedwith great potential and confidence for the evolution of complete life cycle of monsoon over the Indianregion for different years. 相似文献
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气溶胶辐射特性的观测研究 总被引：40，自引：5，他引：35
利用一个简化的辐射平衡模式,讨论了气溶胶直接辐射强迫和气溶胶辐射特性以及与地面反射率之间的关系。模式分析表明,增加气溶胶层以后,地气系统对太阳辐射的反射率可能增大,也可能减少,取决于气溶胶的单散射反射率~ω0、不对称度因子g与地面反射率αg之间的配置,但与气溶胶光学厚度δ没有直接的关系。气溶胶光学厚度值仅和反射率变化的幅度成正比。从辐射平衡模式的结果可知,为了定量地研究气溶胶直接辐射强迫作用,需要有系统的有关气溶胶辐射特性的观测资料。从地面和空间对中国地区气溶胶的辐射特性开展了观测研究,包括从地面用太阳光度计测量气溶胶的光学厚度、用浊度计测量气溶胶的散射系数、黑碳仪测量气溶胶的吸收系数,并且利用MODIS资料反演气溶胶的光学厚度。地面太阳光度计观测的气溶胶光学厚度用于检验卫星遥感的气溶胶光学厚度值,对中国东部地区,遥感的结果是可以接受的,主要是由于这一地区存在较低的地表反射率;但对中国北方植被条件不很好的地区,在遥感反演时对地面反射率的估计可能偏低,如做适当的修改还有可能提高遥感反演的精度。从地面直接测量气溶胶的散射系数和吸收系数算出的气溶胶单散射反射率在0.8左右,需要有更多的观测,以便进一步查清这一问题。 相似文献
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利用ERBE资料分析中国地区云辐射强迫的时空变化 总被引：7，自引：3，他引：4
利用１９８５￣１９８８年４年的ＥＲＢＥ资料,分析和揭示了我国大陆地区云辐射强迫变化的一些基本事实。结果发现：云强迫存在很大的区域差异和较强的季节变化,其中川黔地区是全国最大的云强迫负值区,其次是长江中下游地区和华北地区青藏高原为正、负值的过渡区,高原北侧的西北干旱区冬季为较弱的云强迫正值区。此外,云强迫还具有一定的年际变化。 相似文献
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相对湿度对气溶胶辐射特性和辐射强迫的影响 总被引：14，自引：4，他引：14
采用已有的气溶胶折射指数等资料 ,计算了在不同的相对湿度条件下硫酸盐气溶胶的辐射特性。结合两种不同化学输送模式 (CTM )的模拟结果及LASGGOALS/AGCM模式 ,模拟估算了考虑相对湿度影响后全球硫酸盐气溶胶的辐射强迫。结果表明 :(1)随着相对湿度的增加 ,硫酸盐气溶胶的质量消光效率因子在短波波段有所减小 ,单次散射反照率仅在长波波段有所增加 ,不对称因子在整个波段均有所增加 ;(2 )用两个CTM资料模拟辐射强迫的结果相差较大 ,其全球平均辐射强迫分别为 - 0 .2 6 8和 - 0 .816W/m2 ;(3)在考虑相对湿度的影响后 ,硫酸盐气溶胶辐射强迫的分布类型与相应干粒子的强迫分布类型基本相同 ,但全球平均的强迫值减少了 6 %左右。 相似文献
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In this paper, we analyze the effects of radiative cooling on the pure baroclinic low-frequency waves under the approximation of equatorial β-plane and semi-geostrophic condition. The results show that radiative cooling does not, exclusively, provide the damping effects on the development of low-frequency waves.Under the delicate radiative-convective equilibrium, radiative effects will alter the phase speed and wave period,and bring about the broadband of phase velocity and wave period by adjusting the vertical profiles of diabaticheating. When the intensity of diabatic heating is moderate and appropriate, it is conductive to the development and sustaining of the low-frequency waves and their broadband phenomena, not the larger, the better. The radiative cooling cannot be neglected in order to reach the moderate and appropriate intensity of diabatic heating. 相似文献
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The International Centre for Theoretical Physics(ICTP,Italy) Regional Climate Model version 3.0(RegCM3) is used to simulate spatio-temporal distribution characteristics and radiative forcing(RF) of organic carbon(OC) aerosols in and around China.The preliminary simulation results show that OC aerosols are mostly concentrated in the area to the south of Yellow River and east of Tibetan Plateau.There is a decreasing trend of column burden of OC aerosols from south to north in China.The maximum value of column burden of OC aerosols is above 3 mg/m2 and located in the central and southern China,southeastern Tibet,and southwestern China’s Yunnan,Guizhou,Sichuan provinces.The simulation on the seasonal variation shows that the maximum value of column burden of OC aerosols appears in winter and the secondary value is in spring and the minimum in summer.The RF of OC aerosols which varies seasonally is negative at the top of the atmosphere(TOA) and surface.The spatio-temporal characteristics of the RF of OC aerosols are basically consistent with that of IPCC,implying the high accuracy of the parameterization scheme for OC aerosols in RegCM3. 相似文献
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硫酸盐气溶胶直接辐射效应在线与离线模拟方法的比较 总被引：3，自引：0，他引：3
利用区域气候模式RegCM 2与大气化学模式连接的模拟系统 ,比较了硫酸盐气溶胶辐射强迫的在线、离线模拟方法的硫酸盐柱含量、大气顶直接辐射强迫及地表温度响应。发现 :在线与离线模拟方法得到的硫酸盐柱含量、有无反馈大气顶直接辐射强迫和地表温度响应在许多地区有很大差异 ,这种差异在较小区域平均的尺度上更显著 ,在全区域平均尺度上也较为明显 ,是不能被忽略的 ;结果显示从硫酸盐含量到辐射强迫和地表温度响应逐渐加大的差异 ,说明硫酸盐气溶胶的辐射强迫与模拟方法有关 ,显示出较大的不确定性。 相似文献
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以2000年1、4、7、10月为例，利用区域气候模式，比较了模拟硫酸盐气溶胶分布和直接辐射强迫的在线模拟方法与固定SO2到硫酸盐转化率方法，并与全球模式的结果进行了对比检验。结果表明：在线模拟得到的主要结果与全球平均结果符合得很好，但固定转化率方法存在明显偏差；两种方法硫酸盐柱含量的差异在-4-12mg／m^2范围内，占在线模拟柱含量的42％以上，7月份差异最显著，1月份差异最小；大气顶辐射强迫差异在-1.8-0．4W／m^2之间，此差别占在线辐射强迫的26％以上；采用36．7％的固定转化率对冬季过大、夏季偏小，只有春秋季的江南部分地区适合。由于固定转化率方法不能反映温度、辐射、水汽、云水等气象要素的季节性变化对硫酸盐生成率的影响，因而对硫酸盐含量和分布的季节变化模拟存在偏差，这是导致上述差异的重要原因。 相似文献
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东亚地区云和地表反照率对硫酸盐直接辐射强迫的影响 总被引：9，自引：3，他引：9
文中利用区域气候模式深入探讨了东亚地区云及地表反照率对硫酸盐直接辐射强迫的影响 ,同时定量估算了东亚地区云区气溶胶的直接辐射强迫 ,讨论了硫酸盐对地表和大气短波辐射平衡产生的不同影响。研究表明 :云对气溶胶的直接辐射强迫具有很强的减弱作用 ,这种减弱作用不仅取决于云覆盖份数 ,而且取决于云的光学厚度。就区域平均而言 ,文中模拟的东亚地区气溶胶直接辐射强迫为 - 0 .0 97W /m2 ,占总直接辐射强迫的 10 .4%左右。表明云对硫酸盐直接辐射具有很强的减弱作用 ,在估算其总的直接辐射强迫时 ,云区的贡献不可忽视。较高的地表反照率会减弱硫酸盐的直接辐射强迫 ,而较低地表反照率则会增加硫酸盐的辐射强迫。硫酸盐气溶胶对大气辐射平衡影响非常小 ,但对地表辐射平衡产生重要影响 ,影响程度与大气几乎一致。 相似文献