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1.
The evolution of smoke plume over European Russia (ER) during the massive forest and peatbog fires of summer 2010 has been studied using observations of aerosol optical depth (AOD) from MODIS instruments (both Aqua and Terra platforms), objective analysis of meteorological fields performed at the Russian Hydrometeorological Research Center, NCEP/NCAR reanalysis, as well as upper air data. A relation between the structure inhomogeneities of the AOD field and regional atmospheric circulation has been found. It is shown that, on August 5–9, 2010, the maximum of smoke pollution did complete turn around Moscow, while remaining at a distance of 200 to 650 km from the megacity. Both regionally averaged shortwave aerosol radiative forcings (ARFs) at the top and the bottom of the atmosphere are estimated for the period of extreme smoke pollution over ER. The spatial distributions of ARF values over the territory of the region and the estimates of the local and spatially distributed thermal effects of smoke aerosol are given. It is shown that, on August 5–9, 2010, the spatial distribution of AOD and the calculated thermal effects of smoke aerosol were in agreement with the spatial distributions of air-temperature anomalies observed in the lower 1.5-km layer of the atmosphere. MODIS’s AOD data obtained during the wildfires were validated by AOD observations from the CIMEL sun photometer operated at the AERONET station Zvenigorod.  相似文献   

2.
The results of studies into the aerosol optical depth (AOD) for the atmosphere in the Middle Urals in the spectrum range of 0.34–1.02 μm for 2004–2010 is presented. The interannual, annual, seasonal, and daily variations in the AOD are analyzed. The major statistical characteristics of the AOD, the parameters of the probability density function of distributions over different wave lengths, and the parameters of Angstrom’s formula for the different seasons are calculated. The monitoring stations in the Russian segment of the AERONET network are ranked with respect to the AOD value. A shift from March to May in the spring maximum of the AOD is revealed in comparison with the results of the actinometric observations for the period of 1960–1986. A qualitative assessment is given to the influence of forest and peat fires in the region on the AOD. A classification of the states of aerosol haze in the atmosphere according to the AOD values is proposed.  相似文献   

3.
The aerosol longwave radiative forcing of the atmosphere and heating rate of the near-surface aerosol layer are estimated for the extreme smoke conditions in the Moscow region in summer 2010. Thermal radiation fluxes in the atmosphere are determined using the integral transmission function and semiempirical aerosol model developed on the basis of standard aerosol models and measurements at the Zvenigorod Scientific Station, Obukhov Institute of Atmospheric Physics, Russian Academy of Sciences. The aerosol radiative forcing reached 33 W/m2 at the lower atmospheric boundary and ranged between–1.0 and 1.0 W/m2 at the upper atmospheric boundary. The heating rate of the 10-m atmospheric layer near surface was up to 0.2 K/h during the maximum smoke conditions on August 7–9. The sensitivity of the aerosol longwave radiative forcing to the changes in the aerosol absorption coefficient and aerosol optical thickness are estimated.  相似文献   

4.
The shortwave radiative forcings of smoke aerosol in the cloudless atmosphere during the summer fires of 2010 in European Russia were quantitatively estimated for the land surface and the atmospheric upper boundary from measurement data obtained at the Zvenigorod Scientific Station of the Obukhov Institute of Atmospheric Physics (OIAP ZSS), Russian Academy of Sciences. Variations in the temperature of the surface air layer due to the smoke-induced attenuation of incoming solar radiation were estimated. The most intensive smoke generation in the atmosphere was observed on August 7–9, 2010, when the maximum aerosol optical thickness amounted to more than 4.0 at a wavelength of 550 nm. In this case, the albedo of single aerosol scattering amounted to ∼0.95–0.96 and the asymmetry factor amounted to ∼0.69–0.70. The maximum shortwave radiative forcing of aerosol amounted to about −360 W/m2 for the land surface and almost −150 W/m2 for the atmospheric upper boundary. During the period of intensive smoke generation, the cooling of the atmospheric surface layer over daylight hours (12 h) amounted, on average, to ∼6°C. The power character of the dependence of the shortwave radiative forcing of aerosol for the land surface on aerosol optical thickness up to its values exceeding 4.0, which was revealed earlier on the basis of data on aerosol optical thickness (up to 1.5) obtained at the OIAP ZSS during the summer forest and peatbog fires of 2002 in the region of Moscow, was supported.  相似文献   

5.
The results of studies of aerosol optical thickness (AOT) in Dushanbe conducted from July 2010 to March 2011 within the AERONET program are discussed. The statistical characteristics of AOT have been shown to significantly vary during dust intrusions. The seasonal variations in the dustiness of the atmosphere have been analyzed.  相似文献   

6.
Based on mathematical simulation, quantitative estimates of the effect that coarse dust particles have on the accuracy of retrieving the optical characteristics of aerosol have been obtained from the results of ground-based measurements of the spectral fluxes of both direct and scattered solar radiations. The results of verifying a retrieval algorithm (used at the AERONET ground-based network) based on special test models showed that the aerosol characteristics retrieved with this algorithm are unsuitable for calculating integral solar fluxes and for simulating space spectrometric IR measurements when the concentration of dust particles in the atmosphere exceeds their concentration in the well-known CONT model of continental aerosol by a factor of two or more.  相似文献   

7.
dimethylsulphide (DMS)的海空通量是海洋生物气溶胶的主要来源之一,对气候（特别是北冰洋的气候）具有重要的辐射影响。利用卫星数据得到的气溶胶光学深度(AOD)作为气溶胶负荷的代表,在夏季和秋季表现的尤其明显。春季海冰的融化是北极气溶胶前体的重要来源。然而,早春的高浓度气溶胶可能与南方大陆污染的平流有关(北极霾)。更高的AOD通常在研究区域的南部出现。海冰浓度(SIC)和AOD呈正相关,而云盖(CLD)和AOD则呈负相关。SIC和CLD的季节性峰值均在AOD峰值的前一个月。AOD与SIC之间存在强烈的正相关关系。融冰与叶绿素（CHL)几乎在3月至9月呈正相关,但与春季和初夏的AOD呈负相关。春季和初夏较高的AOD有可能是由融冰和春季强风在该地区的结合影响。由于春季风的升高和冰的融化,在春季出现了DMS通量的峰值。从3月到五月,DMS浓度和AOD及融冰都呈正相关。早秋季升高的AOD可能与浮游植物合成的生物气溶胶的排放有关。到2100年，格陵兰海的DMS通量将增加3倍以上。生物气溶胶的显著增加可以部分抵消格陵兰海的增温现象。  相似文献   

8.
The results of 2-year (2010–2012) measurements of the concentrations of organic carbon (OC) and elemental carbon (EC), which were taken at the Zotino Tall Tower Observatory (ZOTTO) Siberian background station (61° N, 89° E), are given. Despite the fact that this station is located far from populated areas and industrial zones, the concentrations of OC and EC in the atmosphere over boreal forests in central Siberia significantly exceed their background values. In winter and fall, high concentrations of atmospheric carbonaceous aerosol particles are caused by the long-range transport (~1000 km) of air masses that accumulate pollutants from large cities located in both southern and southwestern regions of Siberia. In spring and summer, the pollution level is also high due to regional forest fires and agricultural burning in the steppe zone of western Siberia in the Russian–Kazakh border region. Background concentrations of carbonaceous aerosol particles were observed within relatively short time intervals whose total duration was no more than 20% of the entire observation period. In summer, variations in the background concentrations of OC closely correlated with air temperature, which implies that the biogenic sources of organic-particle formation are dominating.  相似文献   

9.
Methods and algorithms for the retrieval of optical characteristics of the aerosol atmosphere and underlying surface by data from a multispectral satellite sensor (MSSS) are described. A procedure for the joint processing of MSSS and multizonal imaging system (MZIS) data is proposed and described with the aim of retrieving the albedo of the Earth’s surface with a high spatial resolution. In this case the spectral optical characteristics of the aerosol atmosphere are retrieved by MSSS data in the visible range of 400–700 nm. According to these results, transmission functions of the atmosphere in MZIS spectral channels are calculated and an atmospheric correction of MZIS data is performed. The accuracy of determining the albedo of the underlying surface in spectral channels of MZIS with high-spatial-resolution is estimated.  相似文献   

10.
A scheme of interpreting the data of two-wavelength lidar sounding is proposed. The scheme is based on functional relationships between the lidar ratios and between some integral characteristics of aerosol and the ratio of the backscattering coefficients at the sounding wavelengths. The AERONET data, results of contact aerosol measurements and multiwavelength lidar sounding, and the OPAC aerosol model are used to find these functional relationships, which are statistical in character. Analysis of data is made separately for continental, dust, oceanic, and smoke aerosols. Backscattering for mineral aerosol fractions are calculated for a model of randomly oriented spheroids. A numerical experiment shows that the errors in determining a number of integral parameters of aerosol (extinction coefficient, characteristic radius of particles, volume concentrations) that are due to the statistical straggling of lidar ratios and other specified integral characteristics are no greater than 32% if the optical thickness of the sounding layer is no greater than 1.  相似文献   

11.
Aerosol optical thickness (AOT) was retrieved from the Geostationary Ocean Color Imager (GOCI) on board the Communication, Ocean, and Meteorological Satellite (COMS) for the first time. AOT values were retrieved over the ocean at a spatial scale of 0.5 × 0.5 km2 by using the look-up table (LUT)-based separation technique. The radiative transfer model (RTM) was used for different models of atmosphere-ocean environmental conditions, taking into account the realistic variability of scattering and absorption. Ocean surface properties affected by whitecaps and pigment content were also taken into account. The results show that the radiance observed by the GOCI amounts to only 5% of the radiation that penetrated the ocean and, consequently, 95% of the radiation is scattered in the atmosphere or reflected at the ocean surface in the visible wavelengths longer than 0.6 ìm. Within these wavelengths, radiance variations at the top of atmosphere (TOA) due to pigment variations are within 10%, while the radiance variation due to wind speed is considerably higher. For verification of GOCI-retrieved AOTs, comparison between GOCI and ground-based sunphotometer measurement at Gosan, Korea (126.10°E, 33.23°N)) showed good correlation (r = 0.99). The GOCI observations obtained by using the proposed technique showed promising results for the daily monitoring of atmospheric aerosol loading as well as being useful for environmental supervisory authorities.  相似文献   

12.
Estimates of some aerosol and radiation characteristics of the atmosphere in the summer of 2010 are obtained according to the results of the measurements made at the Meteorological Observatory (MO) at Moscow State University and are compared with the results of the measurements performed in 2002 and 1972 during the forest and peat fires. In contrast to 1972 and 2002, the period under study in 2010 is characterized by a greater frequency of the highest class of fire danger according to Nesterov, higher aerosol optical depths of the atmosphere up to 4.6, and a more significant weakening of solar radiation in different spectrum regions. In 2010 the smoke aerosol caused losses of the total shortwave radiation of 33%, visible radiation of 39%, ultraviolet radiation of 300–380 nm of 51%, and erythemal radiation of 63%. At the same time, an increase in the downward long-wave radiation to 40–50 W/m2 under extreme aerosol optical depths is recorded.  相似文献   

13.
The surface area and volume densities (S and V) of the particles of stratospheric background aerosol in the 15–20 km and 20–25 km layers for 2002–2005 were obtained from measurements of the aerosol extinction coefficient with the SAGE III instrument by using the linear-regression method of solving the inverse problem. The measurements were taken within the latitudinal belts 43°–80°N and 34°–58°S. The spatial and temporal dependences of S and V demonstrate homogeneous distribution fields in summer, whereas noticeable inhomogeneities are observed in winter and early spring. In all years of the measurements, an increase in the integral characteristics of stratospheric background aerosol was observed during the fall-to-winter transition period. Longitudinal variations in S and V can be both slight and significant (50–70%). Analysis of the interannual variability of the mean areas and volumes of aerosol particles shows that their minima (as a rule) were observed in 2002 and their maxima were observed in 2005. In most of the cases, no monotonic annual variations in the aerosol characteristics are noted. The dependence of the aerosol parameters on the phase of the quasi-biennial oscillations of zonal wind in the stratosphere is observed. The data obtained for 2002–2005 are, on the whole, in good agreement with the climatological data obtained for 1996–1999.  相似文献   

14.
Calculation errors in ocean-brightness coefficients in the Far Eastern are analyzed for two atmospheric correction algorithms (NIR and MUMM). The daylight measurements in different water types show that the main error component is systematic and has a simple dependence on the magnitudes of the coefficients. The causes of the error behavior are considered. The most probable explanation for the large errors in ocean-color parameters in the Far East is a high concentration of continental aerosol absorbing light. A comparison between satellite and in situ measurements at AERONET stations in the United States and South Korea has been made. It is shown the errors in these two regions differ by up to 10 times upon close water turbidity and relatively high aerosol optical-depth computation precision in the case of using the NIR correction of the atmospheric effect.  相似文献   

15.
We analyzed measurements of the total carbon monoxide (CO) content in the atmosphere in the region of St. Petersburg (59.88°N, 29.83° E; 20 m above sea level) in the period from 1995 to 2009. The average annual behavior for the entire measurement period has a maximum in February–March and a minimum in July with an amplitude of ～20%. In the absence of strong forest fires in the European part of the Russian Federation and Siberia, the annual minimum of the total CO content is usually recorded in August–September. In winter 1995–2009 (November–January), there was a decrease in the total CO content with a gradual shift in the maximum of the annual behavior from January (1995–1999) to February (2000–2004) and March (2005–2009). The total CO content in January–February 2009 was ～20% lower than the multiyear average level. Estimates of the linear trend for the maximum, minimum, and average values for the period of 1996–2009 showed an absence of statistically significant long-term changes in the total CO content. A spectral analysis of data showed that the spectral components with periods of 12, 14, 17, 24, and 46 months are extracted with 80% confidence. It is shown that the irregular component of the time series of the total CO content (calculated for the period from May to September) agrees well with data on the areas of the forest fires and on the volume of the burnt forest and that 1999, 2001, 2005, 2007, and 2009 can be considered “background” years with the least numbers of forest fires.  相似文献   

16.
Winter convection in the Irminger Sea leading to the formation of Labrador Sea Water (LSW) is analyzed using CTD data collected along the 59.5° N transatlantic section in 2004–2014, winter Argo data from 2012–2014, and daily North American regional reanalysis (NARR). The interannual variability of LSW in the Irminger Sea is investigated. The dissolved oxygen saturation rate of 93% is used to indicate maximal local convection depth. It is shown that the deepest convection (up to 1000 m) resulting in the largest LSW volume that formed in the Irminger Sea in 2008 and 2012. These years were characterized by numerous storms with anomalously strong turbulent heat loss from the ocean to the atmosphere and negative air temperature to the east of the southern tip of Greenland in January–March. LSW became warmer by 0.42°C, saltier by more than 0.03 PSU, and more oxygenated by 8 µmol/kg between 2004 and 2014. A strong LSW decay in the Iceland Basin is also noted.  相似文献   

17.
气象条件对青岛地区气溶胶光学特性的影响   总被引：8，自引：0，他引：8  
利用 2 0 0 2年 4月至 2 0 0 3年 10月多波段太阳光度计资料和同期的气象观测资料 ,分析了不同气象条件下青岛气溶胶光学特性的变化。气象条件的转变与青岛地区气溶胶光学特性之间具有很好的响应关系 :南风盛行时会加大光学厚度 ,并增强气溶胶对 >5 0 0nm波段太阳辐射的散射能力 ;轻雾和霾在青岛气溶胶光学厚度中占有较大比重 ,而霾对 <5 0 0nm波段辐射的散射能力较强。  相似文献   

18.
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19.
由多波段天空辐射计观测的太阳直接辐射和散射辐射计算得到2006年春季22个晴天的大气气溶胶光学厚度(AOD),利用OMI(臭氧监测仪)的气溶胶指数(AI)线性插值得到相应22 d的气溶胶指数,说明AOD与AI具有较好的相关关系,并拟合出两者的线性关系式.分析AOD与实测水平能见度的关系,说明春季在少云或无云天气,大气中气溶胶含量高是导致能见度水平下降的主要原因.根据2个不同的能见度公式,分别由浑浊度系数和消光系数来计算22 d的水平能见度,并与实际观测值做相关,得到相关系数分别为0.764,0.760.当气溶胶标高取1.3 km时,由消光系数计算得到的水平能见度整体小于实测水平能见度;由浑浊度系数计算得到的能见度有11 d大于实测水平能见度,另外11 d小于s实测水平能见度.  相似文献   

20.
Izvestiya, Atmospheric and Oceanic Physics - Using a balance model of the snow layer, we estimate the concentration of black carbon (BC) in the snow; then, with the help of radiative transfer model...  相似文献   

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