首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 140 毫秒
1.
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   

2.
青藏高原五道梁地区大气浑浊度的预测和分析   总被引:2,自引:1,他引:1  
袁福茂  马晓燕 《高原气象》1998,17(2):127-134
利用1993年8月 ̄1995年5月青藏高原王道梁地区MS-120型太阳光度表的预测资料,分析了该地区大气浑浊度的特征。结果表明:(1)该地区上空的大气洁净,受人类活动影响很小,其浑浊度状况与珠峰地区的绒布寺(5000m)及南极地区有相似的最级,但比城市地区要小一个数量组。(2)本区的大气浑浊度具有较明显的季节变化特征,但日变化不明显。(3)大气浑浊度不仅与地面大气状况(地面风向、风速、降水等气象因  相似文献   

3.
兰州冬季的大气浑浊度   总被引:6,自引:3,他引:6  
1980年12月,我们用太阳光度表在兰州市的地面和625米高度处进行了同步测量大气浑浊度的观测。本文利用两个点的观测资料计算了厚度为625米的低层大气的浑浊度。主要结果是:(1)兰州冬季浑浊度高,12月份埃斯川姆浑浊度系数的平均值为0.44。73%的气溶胶粒子集中在低层大气。(2)低层大气和上层大气的浑浊度系数有不同的日变化规律。(3)低层大气和上层大气气溶胶粒子的大小相同。(4)浮尘天气具有浑浊度系数高和波长指数低的特征。(5)谷地内夜间是浑浊物的净积累期,白天是净消散期,夜间的积累常大于白天的消散,使大气浑浊度总是保持着较高的水平。(6)主要浑浊物源是人造源——煤烟。山谷地势和逆温是影响兰州大气浑浊度的两个突出的自然因素。  相似文献   

4.
青藏高原五道梁地区大气浑浊度的观测和分析   总被引:1,自引:1,他引:0  
利用1993年8月~1995年5月青藏高原五道梁地区MS—120型太阳光度表的观测资料,分析了该地区大气浑浊度的特征。结果表明:(1)该地区上空的大气洁净,受人类活动影响很小,其浑浊度状况与珠峰地区的绒布寺(5000m)及南极地区有相似的量级,但比城市地区要小一个数量级。(2)本区的大气浑浊度具有较明显的季节变化特征,但日变化不明显。(3)大气浑浊度不仅与地面大气状况(地面风向、风速、降水等气象因子)关系密切,而且还与测站的地理环境等因素有关。  相似文献   

5.
平流层气溶胶浓度反常对于中国上空大气浑浊度的影响   总被引:1,自引:0,他引:1  
马延华 《大气科学》1982,6(1):65-70
基于1959—1970年五个站太阳直射辐射的观测资料对大气浑浊系数的变化作了评价。结果表明:阿贡山和随后的几个火山爆发导致了1963年秋季以后大气浑浊度的普遍增加,特别是在秋冬季节。进入六十年代末期,当北方的大气浑浊度已明显减少时,南方的大气浑浊度仍保持较高水平,说明平流层气溶胶的传播具有纬度效应。  相似文献   

6.
春季格陵兰海冰变化及与北大西洋涛动和北极涛动的联系   总被引:1,自引:0,他引:1  
采用长序列(1903—1994年)GISST海冰面积和海表温度(SST)资料、NCEP/NCAR再分析资料等,分析了春季格陵兰海冰面积年代际变化特征及其同北大西洋海气变化的关系。结果表明:春季格陵兰海冰面积变化的主要特征可由海冰变化的EOF第一主分量表示。春季海冰变化与前冬NAO/AO以及冬春1—4月份北大西洋墨西哥湾流区SST具有明显的反相变化趋势,且均具有准60a的周期变化特征。海洋向大气的热量输送(感热、潜热)受到海冰变化的显著影响(冰多输送少)。海冰作为大气的冷源,也明显影响地表净辐射的变化。进而,春季海冰变化可影响后期的大气环流变化:海冰面积偏大(偏小),冰岛低压和阿留申低压偏弱(偏强),夏季北非和亚洲大陆的SLP明显偏低(偏高),两大陆夏季热低压加强(减弱)。  相似文献   

7.
利用北京1958—1989年共32年逐日晴空直接辐射资料,计算了大气气溶胶浑浊度系数β值,并结合北京市场用煤资料、天气状况资料和火山爆发资料对β值的年变化及多年变化特征及其成因进行了分析和初步研究。结果表明,北京地区的β值在春季最大,秋末初冬最小;1958—1977年,北京地区β值变化缓慢,维持在0.08—0.12之间,1978年以后,β值有显著增大趋势;一般情况下,非采暖期的β值反而大于采暖期的β值。  相似文献   

8.
我国西北大气沙尘气溶胶的辐射效应   总被引:21,自引:3,他引:18  
沈志宝  魏丽 《大气科学》2000,24(4):541-548
利用HEIFE地面辐射平衡观测资料和同期NOAA-11/AVHRR卫星遥感资料定量估算春季我国西北大气沙尘的辐射效应。大气沙尘减小地面净辐射冷却地面,对地-气系统和大气的辐射效应均与地表反照率有关,严重浑浊的沙尘大气在沙漠为短波加热和长波冷却,在绿洲则相反,但净效应都是加热。文中给出了4月大气浑浊度系数约由0.1增大到0.6,在沙漠和绿洲上空沙尘层(850~600 hPa)内大气的附加短波、长波和净加热/冷却率。  相似文献   

9.
本文使用1961~1995年逐月青藏高原地区大气视热量源汇<Ql>资料、1961~1990年青藏高原地区积雪日数和积雪深度资料、美国NCEP/NCAR的再分析资料以及1975~1994年全球OLR资料,讨论了高原大气热状况年际变化及其与大气环流的关系,发现:高原地区大气热源年际变化明显,其中春季和秋季高原地区<Ql>的变率最大,并且水平分布很不均匀;当冬季高原冷源弱(或强)时,东亚大槽位置偏东(或西),对应着东亚强(或弱)的冬季风;夏季高原热源强(或弱)的年份,在高原及其邻近地区的对流层中、低层为偏差气旋环流(或反气旋环流),在中国长江流域低层为异常的西南风(或东北风),对应着东亚强(或弱)的夏季风,夏季高原热源强度还与南亚高压的强度和位置有关;春季4月的积雪状况与夏季高原大气热源强度有明显关系;夏季高原热源与同期青藏高原东南部、孟加拉湾、中南半岛、东南亚、中国西南部、长江流域和从黄海到到日本海一带对流有明显正相关  相似文献   

10.
黑河实验地区大气浑浊度的初步分析   总被引:2,自引:2,他引:2  
文军  季国良 《高原气象》1994,13(3):339-345
本文利用1991年黑河实验观测期内MS-120型太阳光度表的观测资料,计算分析了该地区临泽,张掖和沙漠三个观测站的大气浑浊度,进而对该地区大气浑浊度的日变化、月际变化,出现频数分布等特征及其影响因子进行了讨论。  相似文献   

11.
The spatial and temporal variations of daily maximum temperature(Tmax), daily minimum temperature(Tmin), daily maximum precipitation(Pmax) and daily maximum wind speed(WSmax) were examined in China using Mann-Kendall test and linear regression method. The results indicated that for China as a whole, Tmax, Tmin and Pmax had significant increasing trends at rates of 0.15℃ per decade, 0.45℃ per decade and 0.58 mm per decade,respectively, while WSmax had decreased significantly at 1.18 m·s~(-1) per decade during 1959—2014. In all regions of China, Tmin increased and WSmax decreased significantly. Spatially, Tmax increased significantly at most of the stations in South China(SC), northwestern North China(NC), northeastern Northeast China(NEC), eastern Northwest China(NWC) and eastern Southwest China(SWC), and the increasing trends were significant in NC, SC, NWC and SWC on the regional average. Tmin increased significantly at most of the stations in China, with notable increase in NEC, northern and southeastern NC and northwestern and eastern NWC. Pmax showed no significant trend at most of the stations in China, and on the regional average it decreased significantly in NC but increased in SC, NWC and the mid-lower Yangtze River valley(YR). WSmax decreased significantly at the vast majority of stations in China, with remarkable decrease in northern NC, northern and central YR, central and southern SC and in parts of central NEC and western NWC. With global climate change and rapidly economic development, China has become more vulnerable to climatic extremes and meteorological disasters, so more strategies of mitigation and/or adaptation of climatic extremes,such as environmentally-friendly and low-cost energy production systems and the enhancement of engineering defense measures are necessary for government and social publics.  相似文献   

12.
Storms that occur at the Bay of Bengal (BoB) are of a bimodal pattern, which is different from that of the other sea areas. By using the NCEP, SST and JTWC data, the causes of the bimodal pattern storm activity of the BoB are diagnosed and analyzed in this paper. The result shows that the seasonal variation of general atmosphere circulation in East Asia has a regulating and controlling impact on the BoB storm activity, and the “bimodal period” of the storm activity corresponds exactly to the seasonal conversion period of atmospheric circulation. The minor wind speed of shear spring and autumn contributed to the storm, which was a crucial factor for the generation and occurrence of the “bimodal pattern” storm activity in the BoB. The analysis on sea surface temperature (SST) shows that the SSTs of all the year around in the BoB area meet the conditions required for the generation of tropical cyclones (TCs). However, the SSTs in the central area of the bay are higher than that of the surrounding areas in spring and autumn, which facilitates the occurrence of a “two-peak” storm activity pattern. The genesis potential index (GPI) quantifies and reflects the environmental conditions for the generation of the BoB storms. For GPI, the intense low-level vortex disturbance in the troposphere and high-humidity atmosphere are the sufficient conditions for storms, while large maximum wind velocity of the ground vortex radius and small vertical wind shear are the necessary conditions of storms.  相似文献   

13.
Observed daily precipitation data from the National Meteorological Observatory in Hainan province and daily data from the National Centers for Environmental Prediction/National Center for Atmospheric Research (NCEP/NCAR) reanalysis-2 dataset from 1981 to 2014 are used to analyze the relationship between Hainan extreme heavy rainfall processes in autumn (referred to as EHRPs) and 10–30 d low-frequency circulation. Based on the key low-frequency signals and the NCEP Climate Forecast System Version 2 (CFSv2) model forecasting products, a dynamical-statistical method is established for the extended-range forecast of EHRPs. The results suggest that EHRPs have a close relationship with the 10–30 d low-frequency oscillation of 850 hPa zonal wind over Hainan Island and to its north, and that they basically occur during the trough phase of the low-frequency oscillation of zonal wind. The latitudinal propagation of the low-frequency wave train in the middle-high latitudes and the meridional propagation of the low-frequency wave train along the coast of East Asia contribute to the ‘north high (cold), south low (warm)’ pattern near Hainan Island, which results in the zonal wind over Hainan Island and to its north reaching its trough, consequently leading to EHRPs. Considering the link between low-frequency circulation and EHRPs, a low-frequency wave train index (LWTI) is defined and adopted to forecast EHRPs by using NCEP CFSv2 forecasting products. EHRPs are predicted to occur during peak phases of LWTI with value larger than 1 for three or more consecutive forecast days. Hindcast experiments for EHRPs in 2015–2016 indicate that EHRPs can be predicted 8–24 d in advance, with an average period of validity of 16.7 d.  相似文献   

14.
Based on the measurements obtained at 64 national meteorological stations in the Beijing–Tianjin–Hebei (BTH) region between 1970 and 2013, the potential evapotranspiration (ET0) in this region was estimated using the Penman–Monteith equation and its sensitivity to maximum temperature (Tmax), minimum temperature (Tmin), wind speed (Vw), net radiation (Rn) and water vapor pressure (Pwv) was analyzed, respectively. The results are shown as follows. (1) The climatic elements in the BTH region underwent significant changes in the study period. Vw and Rn decreased significantly, whereas Tmin, Tmax and Pwv increased considerably. (2) In the BTH region, ET0 also exhibited a significant decreasing trend, and the sensitivity of ET0 to the climatic elements exhibited seasonal characteristics. Of all the climatic elements, ET0 was most sensitive to Pwv in the fall and winter and Rn in the spring and summer. On the annual scale, ET0 was most sensitive to Pwv, followed by Rn, Vw, Tmax and Tmin. In addition, the sensitivity coefficient of ET0 with respect to Pwv had a negative value for all the areas, indicating that increases in Pwv can prevent ET0 from increasing. (3) The sensitivity of ET0 to Tmin and Tmax was significantly lower than its sensitivity to other climatic elements. However, increases in temperature can lead to changes in Pwv and Rn. The temperature should be considered the key intrinsic climatic element that has caused the "evaporation paradox" phenomenon in the BTH region.  相似文献   

15.
正The Taal Volcano in Luzon is one of the most active and dangerous volcanoes of the Philippines. A recent eruption occurred on 12 January 2020(Fig. 1a), and this volcano is still active with the occurrence of volcanic earthquakes. The eruption has become a deep concern worldwide, not only for its damage on local society, but also for potential hazardous consequences on the Earth's climate and environment.  相似文献   

16.
The moving-window correlation analysis was applied to investigate the relationship between autumn Indian Ocean Dipole (IOD) events and the synchronous autumn precipitation in Huaxi region, based on the daily precipitation, sea surface temperature (SST) and atmospheric circulation data from 1960 to 2012. The correlation curves of IOD and the early modulation of Huaxi region’s autumn precipitation indicated a mutational site appeared in the 1970s. During 1960 to 1979, when the IOD was in positive phase in autumn, the circulations changed from a “W” shape to an ”M” shape at 500 hPa in Asia middle-high latitude region. Cold flux got into the Sichuan province with Northwest flow, the positive anomaly of the water vapor flux transported from Western Pacific to Huaxi region strengthened, caused precipitation increase in east Huaxi region. During 1980 to 1999, when the IOD in autumn was positive phase, the atmospheric circulation presented a “W” shape at 500 hPa, the positive anomaly of the water vapor flux transported from Bay of Bengal to Huaxi region strengthened, caused precipitation ascend in west Huaxi region. In summary, the Indian Ocean changed from cold phase to warm phase since the 1970s, caused the instability of the inter-annual relationship between the IOD and the autumn rainfall in Huaxi region.  相似文献   

17.
正While China’s Air Pollution Prevention and Control Action Plan on particulate matter since 2013 has reduced sulfate significantly, aerosol ammonium nitrate remains high in East China. As the high nitrate abundances are strongly linked with ammonia, reducing ammonia emissions is becoming increasingly important to improve the air quality of China. Although satellite data provide evidence of substantial increases in atmospheric ammonia concentrations over major agricultural regions, long-term surface observation of ammonia concentrations are sparse. In addition, there is still no consensus on  相似文献   

18.
基于最新的GTAP8 (Global Trade Analysis Project)数据库,使用投入产出法,分析了2004年到2007年全球贸易变化下南北集团贸易隐含碳变化及对全球碳排放的影响。结果显示,随着发展中国家进出口规模扩张,全球贸易隐含碳流向的重心逐渐向发展中国家转移。2004年到2007年,发达国家高端设备制造业和服务业出口以及发展中国家资源、能源密集型行业及中低端制造业出口的趋势加强,该过程的生产转移导致全球碳排放增长4.15亿t,占研究时段全球贸易隐含碳增量的63%。未来发展中国家的出口隐含碳比重还将进一步提高。贸易变化带来的南北集团隐含碳流动变化对全球应对气候变化行动的影响日益突出,发达国家对此负有重要责任。  相似文献   

19.
Using the International Comprehensive Ocean-Atmosphere Data Set(ICOADS) and ERA-Interim data, spatial distributions of air-sea temperature difference(ASTD) in the South China Sea(SCS) for the past 35 years are compared,and variations of spatial and temporal distributions of ASTD in this region are addressed using empirical orthogonal function decomposition and wavelet analysis methods. The results indicate that both ICOADS and ERA-Interim data can reflect actual distribution characteristics of ASTD in the SCS, but values of ASTD from the ERA-Interim data are smaller than those of the ICOADS data in the same region. In addition, the ASTD characteristics from the ERA-Interim data are not obvious inshore. A seesaw-type, north-south distribution of ASTD is dominant in the SCS; i.e., a positive peak in the south is associated with a negative peak in the north in November, and a negative peak in the south is accompanied by a positive peak in the north during April and May. Interannual ASTD variations in summer or autumn are decreasing. There is a seesaw-type distribution of ASTD between Beibu Bay and most of the SCS in summer, and the center of large values is in the Nansha Islands area in autumn. The ASTD in the SCS has a strong quasi-3a oscillation period in all seasons, and a quasi-11 a period in winter and spring. The ASTD is positively correlated with the Nio3.4 index in summer and autumn but negatively correlated in spring and winter.  相似文献   

20.
Hourly outgoing longwave radiation(OLR) from the geostationary satellite Communication Oceanography Meteorological Satellite(COMS) has been retrieved since June 2010. The COMS OLR retrieval algorithms are based on regression analyses of radiative transfer simulations for spectral functions of COMS infrared channels. This study documents the accuracies of OLRs for future climate applications by making an intercomparison of four OLRs from one single-channel algorithm(OLR12.0using the 12.0 μm channel) and three multiple-channel algorithms(OLR10.8+12.0using the 10.8 and 12.0 μm channels; OLR6.7+10.8using the 6.7 and 10.8 μm channels; and OLR All using the 6.7, 10.8, and 12.0 μm channels). The COMS OLRs from these algorithms were validated with direct measurements of OLR from a broadband radiometer of the Clouds and Earth's Radiant Energy System(CERES) over the full COMS field of view [roughly(50°S–50°N, 70°–170°E)] during April 2011.Validation results show that the root-mean-square errors of COMS OLRs are 5–7 W m-2, which indicates good agreement with CERES OLR over the vast domain. OLR6.7+10.8and OLR All have much smaller errors(~ 6 W m-2) than OLR12.0and OLR10.8+12.0(~ 8 W m-2). Moreover, the small errors of OLR6.7+10.8and OLR All are systematic and can be readily reduced through additional mean bias correction and/or radiance calibration. These results indicate a noteworthy role of the6.7 μm water vapor absorption channel in improving the accuracy of the OLRs. The dependence of the accuracy of COMS OLRs on various surface, atmospheric, and observational conditions is also discussed.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号