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1.
邱金桓 《大气科学》2006,30(5):767-777
引入了一个辐射加权平均的宽带气溶胶一次散射反照率(SSA)的定义,提出了一个从宽带的漫射信息反演该SSA的方法.数值模拟结果表明,在Junge气溶胶谱分布情形下,对气溶胶光学厚度、(A)ngstr(o)m 指数与气溶胶虚部的通常变化范围,应用该SSA所计算的2160组宽带太阳辐射反射率、漫射透过率、总透过率和吸收率的相对标准误差都在1.107%以内; 绝对标准差在0.00287以内.对非Junge的大陆性和都市工业污染气溶胶模式(由水溶性、沙尘和碳粒子组成),在72组反射率、漫射透过率、总透过率和吸收率计算中,相对标准差都在2.047%以内,绝对标准差在0.0075以内.在Junge气溶胶假设下,作者提出了一个综合应用宽带太阳直射和漫射信息同时反演气溶胶光学厚度与辐射加权平均SSA的方法,并通过模拟反演分析了SSA反演的3个主要误差因子.从反演结果可以看出:(1)如果(A)ngstr(o)m指数误差在±0.2以内,对0.55 μm气溶胶光学厚度大于0.312大陆性气溶胶,SSA误差在±0.0418以内;(2)波长无关的宽带地表反照率适用于SSA反演;(3)气溶胶光学厚度越大,辐射资料误差所引起的SSA解误差越小.当辐射误差在±2%以内以及0.55 μm气溶胶光学厚度大于0.312时,SSA解的误差在±0.0149以内; 辐射误差在±4%以内时,SSA解的误差在±0.0317以内.  相似文献   

2.
基于地面太阳短波总辐射对气溶胶光学特性和地表反照率的敏感性, 该文提出了一个评估我国气象台站总辐射资料准确度的方法。该方法选用气溶胶光学厚度和太阳天顶角较小情形下的晴天辐射资料, 从太阳直射辐射反演气溶胶光学厚度, 用于计算宽带透过率, 再从该透过率和总辐射资料反演太阳常数E0, P, 并采用E0, P对世界辐射基准 (WRR) 的偏差表示总辐射资料的不确定性。模拟结果表明:气溶胶折射率虚部和大气柱水汽含量的输入误差是两个主要的评估不确定因子。用于准确度评估的资料越多, 越有利于平滑气溶胶、水汽含量等输入参数随机误差的效应, 评估结果越合理。应用这一方法, 该文评估了2000— 2004年我国沈阳、额济纳旗、北京、乌鲁木齐、格尔木、上海和广州7个气象台站总辐射资料的准确度。7个站共有1161个太阳常数反演值, 都满足太阳天顶角余弦 (μ0) 大于0.7的条件。这些E0, P值对WRR的最大偏差为7.33%, 97.78%的E0, P值对WRR的偏差小于5%, 总平均E0, P值对WRR偏差只有-1.15 %。依据这些结果, 当μ0≥0.7时, 这些台站的晴天总辐射资料的不确定度估计为5%。  相似文献   

3.
本文通过比较太阳直射表和太阳光度计探测的大气柱气溶胶光学厚度,分析了从太阳直射表探测的全波段太阳直射光强信息确定大气柱气溶胶光学厚度的误差,并应用北京观象台的太阳直射表观测资料,反演得到了 1990—1993年北京大气柱气溶胶光学厚度,分析了该光学厚度月与年变化规律以及1991年菲律宾皮纳图博火山爆发对北京大气气溶胶含量的影响。本文还提出了关于有效水汽含量的一个经验关系式,用于确定水汽对太阳辐射的吸收率。  相似文献   

4.
从太阳总辐射信息反演云光学厚度的理论研究   总被引:1,自引:0,他引:1  
邱金桓 《大气科学》1996,20(1):12-21
本文从理论上探讨了从全波段太阳总辐射信息反演云光学厚度的一个新方法,并分析了引起云光学厚度解的误差的主要因子。理论分析和数值试验表明,在大气满足水平均一的条件下,本方法的云光学厚度解的精度主要取决于气溶胶光学特性的确定误差,如果气溶胶光学厚度的误差在30%以内,或折射率虚部的误差在0.02以内,云光学厚度解的误差一般在15%以内。本文还发展了一个二层模式的半经验的δ-Eddington近似,其精度优于Eddington和δ-Eddington近似,而且无须知道云和气溶胶消光系数的垂直分布,适用于本反演算法。  相似文献   

5.
邱金桓  杨理权 《大气科学》2002,26(4):449-458
从宽带的太阳直接辐射1天或1小时累计量(曝辐量)气象观测资料反演气溶胶光学厚度的一个有效方法是很有用的.作者把太阳曝辐量与"等效"的瞬时太阳直接辐射关联起来,建立了一个与曝辐量"等效"的瞬时太阳直接辐射的模式;应用该模式和一个"等效"波长模式,发展了一个从太阳直接曝辐量反演气溶胶光学厚度的方法.作者还从试验上比较分析了由某时刻的宽带太阳直接辐射、每小时或1天的太阳直接辐射曝辐量反演得到的气溶胶光学厚度以及由太阳光度计探测的气溶胶光学厚度.试验结果表明,由日太阳直接辐射曝辐量反演得到的气溶胶光学厚度可理解为辐射加权的日平均光学厚度.  相似文献   

6.
CE318太阳光度计基本结构与安装使用   总被引:1,自引:0,他引:1  
陈征 《陕西气象》2002,(5):43-44
CE31 8自动跟踪太阳光度计是由法国CIMEL公司研制生产、用于气溶胶光学特性和大气质量监测的自动测量仪器 ,它不仅能自动跟踪太阳作太阳直射辐射测量 ,而且可以进行太阳等高度角天空扫描、太阳主平面扫描和极化通道天空扫描。CE31 8能自动存储测量数据 ,并可自动传输到计算机保存及发送。 CE31 8测得的直射太阳辐射数据可用来反演计算大气透过率、消光光学厚度、气溶胶光学厚度、大气水汽柱总量和臭氧总量。其天空扫描数据可以反演大气气溶胶粒子尺度谱分布及气溶胶相函数。 CE31 8可用于卫星遥感产品检验和气溶胶气候研究 ,在大气光…  相似文献   

7.
黑碳气溶胶光学厚度的全球分布及分析   总被引:11,自引:2,他引:11  
马井会  郑有飞  张华 《气象科学》2007,27(5):549-556
利用全球气溶胶数据集GADS(Global Aerosol Data Set)计算了冬夏两季黑碳气溶胶质量浓度分布以及在波长0.55μm处的光学厚度、吸收系数和散射系数在全球的分布,并分析了原因。通过分析黑碳气溶胶复折射指数虚部、单次散射反照率、非对称因子、吸收系数、散射系数和消光系数随波长的变化,得出黑碳气溶胶的吸收系数和散射系数在小于0.5μm的短波范围内具有相同的数量级,随着波长的增大,吸收系数比散射系数大几个数量级;黑碳气溶胶对小于1μm的短波有强烈的吸收作用。另外还给出了冬夏两季南北半球及全球黑碳气溶胶平均光学厚度值、7个地区黑碳气溶胶光学厚度及质量浓度最大值,其中冬季黑碳气溶胶光学厚度的最大值为0.027 5,位于东亚地区;而质量浓度最大值为1.555μg/m3,位于西欧地区。  相似文献   

8.
珠穆朗玛峰地区大气气溶胶光学特性   总被引:4,自引:3,他引:4       下载免费PDF全文
李放  吕达仁 《大气科学》1995,19(6):755-763
本文提出了用宽带辐射资料回归内插求取大气光学厚度谱的方法。利用1966年和1968年珠穆朗玛峰地区科学考察期间得到的太阳直接辐射光谱资料,获得了该地区大气气溶胶光学厚度谱。最高观测站东绒布冰川(海拔6300m)波长在0.55 μm的气溶胶光学厚度春季平均为0.044±0.017,与南极地区有相似的量级,比内陆人口密集地区小一个数量级。由光学厚度谱反演出了珠峰地区的大气气溶胶的粒子谱分布特征,并与包括1986年中美西藏科学考察结果在内的诸多资料做了对比。研究表明,拉萨的大气气溶胶光学厚度在1966—1986的20年间平均约有1.8%的年增长率。  相似文献   

9.
中国10个地方大气气溶胶1980~1994年间变化特征研究   总被引:23,自引:3,他引:23       下载免费PDF全文
作者发展了一个从地面上太阳短波直射辐射和能见度信息综合确定大气柱气溶胶总光学厚度和平流层气溶胶光学厚度的方法,并应用这个方法从气象台站观测资料反演得到北京、昆明、喀什、上海、广州、郑州、沈阳、武汉、格尔木和乌鲁木齐等10个地方从1980到1994年间晴天气溶胶光学厚度资料,分析了这些地方气溶胶光学厚度月变化和年变化特征,并侧重分析了1982年墨西哥厄尔奇琼火山和1991年菲律宾皮纳图博火山爆发对气溶胶光学厚度的影响。  相似文献   

10.
关于中国大气气溶胶光学厚度的一个参数化模式   总被引:16,自引:3,他引:16  
邱金桓  林耀荣 《气象学报》2001,59(3):368-372
应用中国 1 6个气象台站探测的 1 990年太阳宽带直射辐射信息 ,反演得到了这些台站大气气溶胶光学厚度资料 ,发展了一个应用地面气象能见度和水汽压信息确定大气柱气溶胶光学厚度的参数化模式 ,它比 Elterman模式更适合中国的广大地区。研究还发现 ,比较 Elter-man气溶胶粒子浓度垂直分布模式 ,中国许多地方气溶胶粒子浓度垂直衰减较慢。  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.
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   

17.
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   

18.
正AIMS AND SCOPE Atmospheric and Oceanic Science Letters (AOSL) publishes short research letters on all disciplines of the atmosphere sciences and physical oceanography. Contributions from all over the world are welcome.SUBMISSIONAll submitted  相似文献   

19.
20.
《大气和海洋科学快报》2014,(5):F0003-F0003
AIMS AND SCOPE Atmospheric and Oceanic Science Letters (AOSL) pub- lishes short research letters on all disciplines of the atmos- phere sciences and physical oceanography. Contributions from all over the world are welcome.  相似文献   

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