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1.
Climate forcing by carbonaceous and sulfate aerosols 总被引：3，自引：0，他引：3
An atmospheric general circulation model is coupled to an atmospheric chemistry model to calculate the radiative forcing
by anthropogenic sulfate and carbonaceous aerosols. The latter aerosols result from biomass burning as well as fossil fuel
burning. The black carbon associated with carbonaceous aerosols is absorbant and can decrease the amount of reflected radiation
at the top-of-the-atmosphere. In contrast, sulfate aerosols are reflectant and the amount of reflected radiation depends nonlinearly
on the relative humidity. We examine the importance of treating the range of optical properties associated with sulfate aerosol
at high relative humidities and find that the direct forcing by anthropogenic sulfate aerosols can decrease from −0.81 W m-2 to −0.55 Wm-2 if grid box average relative humidity is not allowed to increase above 90%. The climate forcing associated with fossil fuel
emissions of carbonaceous aerosols is calculated to range from +0.16 to +0.20 Wm-2, depending on how much organic carbon is associated with the black carbon from fossil fuel burning. The direct forcing of
carbonaceous aerosols associated with biomass burning is calculated to range from −0.23 to −0.16 Wm-2. The pattern of forcing by carbonaceous aerosols depends on both the surface albedo and the presence of clouds. Multiple
scattering associated with clouds and high surface albedos can change the forcing from negative to positive.
Received: 29 September 1997 / Accepted: 10 June 1998 相似文献
2.
A regional climate model is employed to simulate the aerosols(dust,sulfate,black carbon,and organic carbon) and their direct effect on the climate over China.The emphasis is on the direct radiative forcing due to the change in mixing state of aerosols.The results show that direct radiative forcing is significantly different between externally and internally mixed aerosols.At the top of the atmosphere(TOA),the radiative forcing of externally mixed aerosols is larger than that of internally mixed ones,especially in the Tarim desert region where the difference is about 0.7 W m 2.At the surface,however,the situation becomes opposite,especially in the Sichuan basin where the difference is about-1.4 W m 2.Nonetheless,either externally or internally mixed aerosols in China can result in a significant cooling effect,except for the warming in South China in winter and the slight warming in North China in February.The cooling effect induced by externally mixed aerosols is weaker than that induced by internally mixed aerosols,and this is more obvious in spring and winter than in summer and autumn.In spring and summer,the inhibiting effect of externally mixed aerosols on precipitation is less than that of internally mixed aerosols,whereas in autumn and winter the difference is not obvious. 相似文献
3.
黄土高原半干旱区典型日吸收性气溶胶综合观测分析 总被引：2，自引：0，他引：2
利用兰州大学半干旱气候与环境观测站的太阳光度计、激光雷达、微波辐射计综合观测资料,结合辐射传输模式分析了该地区秋季典型日2012年9月3~4日、21日和28日气溶胶物理特性、垂直分布特征,及其与气象条件的关系。研究时期的气溶胶主要为局地沙尘与人为污染混合气溶胶,吸收性明显,尺度较小。其中,4日西北风增强,远距离传输沙尘气溶胶,气溶胶光学厚度最大,粒子尺度明显增大。尝试利用灰色关联度法确定参考高度,分别为7.41 km、8.47 km、7.13 km和7.66 km,反演气溶胶消光系数,由此积分得到的光学厚度与太阳光度计观测值相关性可达0.975,反演效果较好。研究时期气溶胶的抬升主要受白天热力湍流作用,边界层发展,气溶胶向上传输,每日12时（当地时间,下同）至14时传输至最大高度,气溶胶抬升的高度对应大气加热率的高值区,低层加热率可达1 K d-1。气溶胶在大气层顶和地面造成负辐射强迫,分别为-12.707 W m-2、-25.398 W m-2,大气中表现为正辐射强迫,为12.692 W m-2,大气层顶的辐射强迫对气溶胶的物理特性最为敏感,当气溶胶吸收性明显时,大气层顶的瞬时辐射强迫会出现正值。 相似文献
4.
The atmospheric general circulation model ECHAM-4 is coupled to a chemistry model to calculate sulfate mass distribution
and the radiative forcing due to sulfate aerosol particles. The model simulates the main components of the hydrological cycle
and, hence, it allows an explicit treatment of cloud transformation processes and precipitation scavenging. Two experiments
are performed, one with pre-industrial and one with present-day sulfur emissions. In the pre-industrial emission scenario
SO2 is oxidized faster to sulfate and the in-cloud oxidation via the reaction with ozone is more important than in the present-day
scenario. The atmospheric sulfate mass due to anthropogenic emissions is estimated as 0.38 Tg sulfur. The radiative forcing
due to anthropogenic sulfate aerosols is calculated diagnostically. The backscattering of shortwave radiation (direct effect)
as well as the impact of sulfate aerosols on the cloud albedo (indirect effect) is estimated. The model predicts a direct
forcing of −0.35 W m-2 and an indirect forcing of −0.76 W m-2. Over the continents of the Northern Hemisphere the direct forcing amounts to −0.64 W m-2. The geographical distribution of the direct and indirect effect is very different. Whereas the direct forcing is strongest
over highly polluted continental regions, the indirect forcing over sea exceeds that over land. It is shown that forcing estimates
based on monthly averages rather than on instantaneous sulfate pattern overestimate the indirect effect but have little effect
on the direct forcing.
Received: 16 October 1996/Accepted: 24 October 1996 相似文献
5.
The air quality model system RAMS (Regional Atmospheric Modeling System)-CMAQ (Models-3 Community Multi-scale Air Quality) coupled with an aerosol optical/radiative module was applied to investigate the impact of different aerosol mixing states (i.e., externally mixed, half externally and half internally mixed, and internally mixed) on radiative forcing in East Asia. The simulation results show that the aerosol optical depth (AOD) generally increased when the aerosol mixing state changed from externally mixed to internally mixed, while the single scattering albedo (SSA) decreased. Therefore, the scattering and absorption properties of aerosols can be significantly affected by the change of aerosol mixing states. Comparison of simulated and observed SSAs at five AERONET (Aerosol Robotic Network) sites suggests that SSA could be better estimated by considering aerosol particles to be internally mixed. Model analysis indicates that the impact of aerosol mixing state upon aerosol direct radiative forcing (DRF) is complex. Generally, the cooling effect of aerosols over East Asia are enhanced in the northern part of East Asia (Northern China, Korean peninsula, and the surrounding area of Japan) and are reduced in the southern part of East Asia (Sichuan Basin and Southeast China) by internal mixing process, and the variation range can reach 5 W m－2. The analysis shows that the internal mixing between inorganic salt and dust is likely the main reason that the cooling effect strengthens. Conversely, the internal mixture of anthropogenic aerosols, including sulfate, nitrate, ammonium, black carbon, and organic carbon, could obviously weaken the cooling effect. 相似文献
6.
利用已有的硫酸盐和烟尘气溶胶折射指数资料，精确计算了这两种气溶胶从太阳短波到红外谱段的辐射特性。然后，在LLNL化学输送模式(CTM)模拟的硫酸盐和烟尘气溶胶资料及改进的气溶胶参数化基础上，在国内首次用GCM估算了这两种气溶胶引起的全球辐射强迫。结果表明:(1)西欧是全球最大的硫酸盐辐射强迫中心，最大值出现在夏季，达-5.0W/m2；(2)烟尘强迫的最大中心出现在夏季的南美和非洲中南部，为4.0W/m2；(3)南半球大陆人为气溶胶的强迫不容忽视；(4)某些地区人为气溶胶的强迫在量值上可与CO2等温室气体引起的强迫相比拟。 相似文献
7.
S. Gonzi O. Dubovik D. Baumgartner E. Putz 《Meteorology and Atmospheric Physics》2007,96(3-4):277-291
Summary One of the great unknowns in climate research is the contribution of aerosols to climate forcing and climate perturbation.
In this study, retrievals from AERONET are used to estimate the direct clear-sky aerosol top-of-atmosphere and surface radiative
forcing effects for 12 multi-site observing stations in Europe. The radiative transfer code sdisort in the libRadtran environment is applied to accomplish these estimations. Most of the calculations in this study rely on observations which
have been made for the years 1999, 2000, and 2001. Some stations do have observations dating back to the year of 1995. The
calculations rely on a pre-compiled aerosol optical properties database for Europe. Aerosol radiative forcing effects are
calculated with monthly mean aerosol optical properties retrievals and calculations are presented for three different surface
albedo scenarios. Two of the surface albedo scenarios are generic by nature bare soil and green vegetation and the third relies on the ISCCP (International Satellite Cloud Climatology Project) data product. The ISCCP database has
also been used to obtain clear-sky weighting fractions over AERONET stations. The AERONET stations cover the area 0° to 30° E
and 42° to 52° N. AERONET retrievals are column integrated and this study does not make any seperation between the contribution
of natural and anthropogenic components. For the 12 AERONET stations, median clear-sky top-of-atmosphere aerosol radiative
forcing effect values for different surface albedo scenarios are calculated to be in the range of −4 to −2 W/m2. High median radiative forcing effect values of about −6 W/m2 were found to occur mainly in the summer months while lower values of about −1 W/m2 occur in the winter months. The aerosol surface forcing also increases in summer months and can reach values of −8 W/m2. Individual stations often have much higher values by a factor of 2. The median top-of-atmosphere aerosol radiative forcing
effect efficiency is estimated to be about −25 W/m2 and their respective surface efficiency is around −35 W/m2. The fractional absorption coefficient is estimated to be 1.7, but deviates significantly from station to station. In addition,
it is found that the well known peak of the aerosol radiative forcing effect at a solar zenith angle of about 75° is in fact
the average of the peaks occurring at shorter and longer wavelengths. According to estimations for Central Europe, based on
mean aerosol optical properties retrievals from 12 stations, the critical threshold of the aerosol single scattering albedo,
between cooling and heating in the presence of an aerosol layer, is close between 0.6 and 0.76. 相似文献
8.
Influences of the mixing treatments of anthropogenic aerosols on their effective radiative forcing (ERF) and global aridity are evaluated by using the BCC_AGCM2.0_CUACE/Aero, an aerosol–climate online coupled model. Simulations show that the negative ERF due to external mixing (EM, a scheme in which all aerosol particles are treated as independent spheres formed by single substance) aerosols is largely reduced by the partial internal mixing (PIM, a scheme in which some of the aerosol particles are formed by one absorptive and one scattering substance) method. Compared to EM, PIM aerosols have much stronger absorptive ability and generally weaker hygroscopicity, which would lead to changes in radiative forcing, hence to climate. For the global mean values, the ERFs due to anthropogenic aerosols since the pre-industrial are–1.02 and–1.68 W m–2 for PIM and EM schemes, respectively. The variables related to aridity such as global mean temperature, net radiation flux at the surface, and the potential evaporation capacity are all decreased by 2.18/1.61 K, 5.06/3.90 W m–2, and 0.21/0.14 mm day–1 since 1850 for EM and PIM schemes, respectively. According to the changes in aridity index, the anthropogenic aerosols have caused general humidification over central Asia, South America, Africa, and Australia, but great aridification over eastern China and the Tibetan Plateau since the pre-industrial in both mixing schemes. However, the aridification is considerably alleviated in China, but intensified in the Arabian Peninsula and East Africa in the PIM scheme. 相似文献
9.
A group of twenty-four leading atmospheric and climate scientists provided subjective probability distributions that represent
their current judgment about the value of planetary average direct and indirect radiative forcing from anthropogenic aerosols
at the top of the atmosphere. Separate estimates were obtained for the direct aerosol effect, the semi-direct aerosol effect,
cloud brightness (first aerosol indirect effect), and cloud lifetime/distribution (second aerosol indirect effect). Estimates
were also obtained for total planetary average forcing at the top of the atmosphere and for surface forcing. Consensus was
strongest among the experts in their assessments of the direct aerosol effect and the cloud brightness indirect effect. Forcing
from the semi-direct effect was thought to be small (absolute values of all but one of the experts' best estimates were ≤0.5
W/m2). There was not agreement about the sign of the best estimate of the semi-direct effect, and the uncertainty ranges some
experts gave for this effect did not overlap those given by others. All best estimates of total aerosol forcing were negative,
with values ranging between −0.25 W/m2 and −2.1 W/m2. The range of uncertainty that a number of experts associated with their estimates, especially those for total aerosol forcing
and for surface forcing, was often much larger than that suggested in 2001 by the IPCC Working Group 1 summary figure (IPCC,
2001). 相似文献
10.
Anthropogenic aerosols play an important role in the atmospheric energy balance. Anthropogenic aerosol optical depth (AOD) and its accompanying shortwave radiative forcing (RF) are usually simulated by nu- merical models. Recently, with the development of space-borne instruments and sophisticated retrieval algorithms, it has become possible to estimate aerosol radiative forcing based on satellite observations. In this study, we have estimated shortwave direct radiative forcing due to anthropogenic aerosols over oceans in all-sky conditions by combining clouds and the Single Scanner Footprint data of the Clouds and Earth’s Radiant Energy System (CERES/SSF) experiment, which provide measurements of upward shortwave fluxes at the top of atmosphere, with Moderate Resolution Imaging Spectroradiometer (MODIS) aerosol and cloud products. We found that globally averaged aerosol radiative forcing over oceans in the clear-sky conditions and all-sky conditions were -1.03±0.48 W m-2 and -0.34 ±0.16 W m-2, respectively. Direct radiative forcing by anthropogenic aerosols shows large regional and seasonal variations. In some regions and in particular seasons, the magnitude of direct forcing by anthropogenic aerosols can be comparable to the forcing of greenhouse gases. However, it shows that aerosols caused the cooling effect, rather than warming effect from global scale, which is different from greenhouse gases. 相似文献
11.
In this study, a regional air quality model system (RAQMS) was
applied to investigate the spatial distributions and seasonal variations of
atmospheric aerosols in 2006 over East Asia. Model validations demonstrated
that RAQMS was able to reproduce the evolution processes of aerosol components
reasonably well. Ground-level PM10 (particles with aerodynamic diameter
≤10 μm) concentrations were highest in spring and lowest in
summer and were characterized by three maximum centers: the Taklimakan Desert
(～1000 μg m-3), the Gobi Desert (～400 μg m-3), and
the Huabei Plain (～300 μm-3) of China. Vertically, high
PM10 concentrations ranging from 100 μg m-3 to 250 μg
m-3 occurred from the surface to an altitude of 6000 m at
30o--45oN in spring. In winter, the vertical gradient was so
large that most aerosols were restricted in the boundary layer. Both sulfate
and ammonium reached their highest concentrations in autumn, while nitrate
reached its maximum level in winter. Black carbon and organic carbon aerosol
concentrations reached maximums in winter. Soil dust were strongest in spring,
whereas sea salt exerted the strongest influence on the coastal regions of
eastern China in summer. The estimated burden of anthropogenic aerosols was
largest in winter (1621 Gg) and smallest in summer (1040 Gg). The sulfate
burden accounted for ～42% of the total anthropogenic aerosol burden. The
dust burden was about twice the anthropogenic aerosol burden, implying the
potentially important impacts of the natural aerosols on air quality and
climate over East Asia. 相似文献
12.
Atmospheric aerosols influence the earth's radiative balance directly through scattering and absorbing solar radiation, and indirectly through affecting cloud properties. An understanding of aerosol optical properties is fundamental to studies of aerosol effects on climate. Although many such studies have been undertaken, large uncertainties in describing aerosol optical characteristics remain, especially regarding the absorption properties of different aerosols. Aerosol radiative effects are considered as either positive or negative perturbations to the radiation balance, and they include direct, indirect (albedo effect and cloud lifetime effect), and semi-direct effects. The total direct effect of anthropogenic aerosols is negative (cooling), although some components may contribute a positive effect (warming). Both the albedo effect and cloud lifetime effect cool the atmosphere by increasing cloud optical depth and cloud cover, respectively. Absorbing aerosols, such as carbonaceous aerosols and dust, exert a positive forcing at the top of atmosphere and a negative forcing at the surface, and they can directly warm the atmosphere. Internally mixed black carbon aerosols produce a stronger warming effect than externally mixed black carbon particles do. The semi-direct effect of absorbing aerosols could amplify this warming effect. Based on observational (ground-and satellite-based) and simulation studies, this paper reviews current progress in research regarding the optical properties and radiative effects of aerosols and also discusses several important issues to be addressed in future studies. 相似文献
13.
人为气溶胶的直接辐射效应及其对南亚冬季风的影响 总被引：2，自引：0，他引：2
运用区域气候模式RegCM4.0(Regional Climate Model Verson 4.0)耦合入一个化学过程,对硫酸盐、黑碳、有机碳这3种人为气溶胶的时空分布特征和直接辐射效应进行了数值模拟,进而研究了气溶胶对南亚冬季风的影响。结果表明:光学厚度和地表短波辐射强迫的时空变化可能主要受硫酸盐气溶胶的影响。在南亚夏季风向冬季风转换时期和南亚冬季风盛行时期,大气层顶和地表的负短波辐射强迫分布与气溶胶分布基本一致,地表辐射强迫强度绝对值比大气层顶辐射强迫强度绝对值大得多。相关分析和合成分析表明:在南亚夏季风向冬季风转换时期和南亚冬季风盛行时期,南亚人为气溶胶主要分布区中的气溶胶柱浓度含量与南亚冬季风的建立和强度有反相关关系。这与气溶胶吸收太阳辐射,从而引起气温和位势高度的变化有关。 相似文献
14.
Why Is the Climate Forcing of Sulfate Aerosols So Uncertain? 总被引：2，自引：0，他引：2
l. IntroductionAlthough the aerosol has been recognized as an important factor which has innuence onthe past, present and future climate for a long time, it still has much uncertainty in assessingits climate forcing. The direct radiative forcing of sulfate aerosols has been estimated rangingfrom --0.3 W/ m2 to --0.9 W/ m2 in recent publications (Charlson et al., l992, Kiehl andBriegleb l993; Taylor and Penner 1994, Boucher and Anderson l995, Kieh1 and Rodhe l995;Chuang et al., l997, Penne… 相似文献
15.
硫酸盐气溶胶辐射强迫的数值模拟研究 总被引：5，自引：0，他引：5
利用IAP/LASG GOALS 4.0海气耦合模式,"显式"考虑了硫酸盐气溶胶的直接作用,并且引入德国马普气象研究所的三维浓度分布资料,模拟计算了硫酸盐气溶胶的辐射强迫.主要结果为:全球气溶胶年平均的辐射强迫为-0.29 W m-2,在IPCC TAR给定的范围内,空间分布上具有明显的地域性,几个大值地区分别为东亚、西欧和北美,它们的中心值均超过-1.5 W m-2,南美、澳大利亚以及非洲南部的辐射强迫介于-0.2～-0.4 W m-2之间,而海洋和偏远的大陆地区,则基本上不受人为硫酸盐气溶胶的影响;计算的东亚地区硫酸盐气溶胶的平均辐射强迫为-0.75 W m-2,约为全球平均的2.5倍,为北半球平均的1.6倍.文中还讨论了全球硫酸盐气溶胶对温室气体辐射强迫的减缓作用. 相似文献
16.
温室气体和硫酸盐气溶胶的辐射强迫作用 总被引：9，自引：4，他引：5
对GOALS4 .0海 陆 气耦合模式的相关部分进行了改进 ,主要改进包括温室气体的扩充和硫酸盐气溶胶“显式”方案的引入 ,并引入 2 0世纪温室气体的实际浓度变化以及硫循环模式模拟的硫酸盐气溶胶的三维全球浓度分布 ,模拟了温室气体和硫酸盐气溶胶造成的辐射强迫的空间分布和时间变化。全球平均的温室气体和硫酸盐气溶胶的辐射强迫分别为 2 .17W /m2 和 - 0 .2 9W /m2 ;温室气体造成的辐射强迫在空间上呈现明显的纬向结构 ,最大值 (大于 2 .5W/m2 )和最小值 (小于 1W /m2 )分别位于副热带和两极地区 ,在北半球主要工业区硫酸盐气溶胶的辐射强迫绝对值接近温室气体的辐射强迫值 (大于 - 2 .0W /m2 )。 相似文献
17.
We summarize an on-line coupled meteorological–emissions–photochemical modelling system that allows feedback from air-quality/chemistry
to meteorology via radiative forcing. We focus on the radiative-forcing impacts (direct effects) of ozone. We present an application
of the coupled modelling system to the episode of 23–31 July 1998 in Portland, Oregon, U.S.A. Results suggest that the inclusion
of radiative-forcing feedback produces small but accountable impacts. For this region and episode, stand-alone radiative transfer
simulations, i.e., evaluating the effects of radiative forcing independently of changes in meteorology or emissions, suggest
that a change of 1 ppb in ground-level ozone is approximately equivalent to a change of 0.017 W m−2 in radiative forcing. In on-line, coupled, three-dimensional simulations, where the meteorological dependencies are accounted
for, domain-wide peak ozone concentrations were higher by 2–4 ppb (relative to a simulated peak of 119.4 ppb) when including
the effects of radiative-forcing feedback. A scenario of 10% reduction in anthropogenic emissions produced slightly larger
decreases in ozone, an additional 1 ppb in local-peak reductions, relative to scenarios without feedback. 相似文献
18.
Indirect Radiative and Climatic Effects of Sulfate and Organic Carbon Aerosols over East Asia Investigated by RIEMS 
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下载免费PDF全文 The indirect radiative and climatic effects of sulfate and organic carbon aerosols over East Asia were investigated using a Regional Integrated Environment Model System (RIEMS) with an empirical aerosol-cloud parameterization.The first indirect radiative forcing was negative and ranged from-9-0 W m-2 in the domain.The maximum cooling,up to-9 W m-2,occurred in the Chongqing District in winter,whereas the cooling areas were larger during summer than in winter.Organic carbon (OC) aerosols were more abundant in winter than in summer,whereas the sulfate concentration during summer was much higher than during winter.The concentrations of sulfate and OC were comparable in winter,and sulfate played a dominant role in determining indirect radiative forcing in summer,whereas in winter,both sulfate and OC were important.The regional mean indirect radiative forcings were-0.73 W m-2 and-0.41 W m-2 in summer and winter,respectively.The surface cooling caused by indirect effects was more obvious in winter than that in summer.The ground temperature decreased by ～1.2 K in most areas of eastern China in winter,whereas in summer,the temperature decreased (～-1.5 K) in some regions,such as the Yangtze River region,but increased (～0.9 K) in the areas between the Yellow and Yangtze Rivers.In winter,the precipitation decreased by 0-6 mm in most areas of eastern China,but in summer,alternating bands of increasing (up to 80 mm) and decreasing (～-80 mm) precipitation appeared in eastern China. 相似文献
19.
Zeinab SALAH Ahmed SHALABY Allison L.STEINER Ashraf S.ZAKEY Ritesh GAUTAM Mohamed M.ABDEL WAHAB 《大气科学进展》2018,35(2):182-194
This study assesses the direct and indirect effects of natural and anthropogenic aerosols(e.g., black carbon and sulfate)over West and Central Africa during the West African monsoon(WAM) period(June–July–August). We investigate the impacts of aerosols on the amount of cloudiness, the influences on the precipitation efficiency of clouds, and the associated radiative forcing(direct and indirect). Our study includes the implementation of three new formulations of auto-conversion parameterization [namely, the Beheng(BH), Tripoli and Cotton(TC) and Liu and Daum(R6) schemes] in Reg CM4.4.1,besides the default model's auto-conversion scheme(Kessler). Among the new schemes, BH reduces the precipitation wet bias by more than 50% over West Africa and achieves a bias reduction of around 25% over Central Africa. Results from detailed sensitivity experiments suggest a significant path forward in terms of addressing the long-standing issue of the characteristic wet bias in Reg CM. In terms of aerosol-induced radiative forcing, the impact of the various schemes is found to vary considerably(ranging from-5 to-25 W m~(-2)). 相似文献
20.
不同污染条件下气溶胶对短波辐射通量影响的模拟研究 总被引：1，自引：0，他引：1
将高光谱分辨率的气溶胶光学参数化方案应用于高精度的辐射传输模式BCC_RAD（974带）中,研究不同污染状况下气溶胶在地表与近地层大气中造成的直接辐射强迫与辐射强迫效率。发现气溶胶在地表产生的直接辐射强迫为负,在近地层大气中产生的直接辐射强迫为正,且随气溶胶浓度的升高变大,说明大气气溶胶的含量越高,单位气溶胶光学厚度产生的直接辐射强迫越大。将短波划分为3个波段:紫外、可见光和近红外,发现在紫外、可见光和近红外波段中,不同污染状况下气溶胶在地表造成的直接辐射强迫范围分别为:-1.36—-13.66、-3.03—-32.41和-2.74—-28.62 W/m2,在近地层大气中产生的直接辐射强迫范围分别为0.44—4.26、0.99—9.80和0.93—8.87 W/m2。通过进一步对比自然和人为气溶胶的影响,发现人为气溶胶在地表和大气层顶产生的负直接辐射强迫以及对整层和近地面大气造成的正直接辐射强迫均大于自然气溶胶的影响,且上述两种排放源的气溶胶对整层大气辐射收支的影响主要集中在800 hPa高度以下的大气中。按照地表直接辐射强迫大小来分析不同种类气溶胶的影响,结果为硫酸盐>有机碳>黑碳>海盐>沙尘;按照近地层大气直接辐射强迫大小排序则为黑碳>有机碳>沙尘>海盐>硫酸盐。最后,通过分析散射型气溶胶与吸收型气溶胶对辐射通量的影响,还探究了大气中散射与吸收过程的异同。 相似文献