STUDY ON SST IN THE NORTHWESTERN PACIFIC OCEAN WITH SATELLITE OBSERVATIONS

On the basis of extracting the clear brightness temperature in GMS-4 infrared data,the testshave been carried out by using three methods for SST retrieval in the northwestern Pacific Ocean inAugust 1993.Considering error amplification is the inherent feature in the single channel physicalmethod,two statistical methods are developed.One is a single channel method.Its precision is1.186℃,which is superior to that of other similar methods.The other is a multi-channel methodusing both TOVS and GMS-4 data.Its precision is 1.061℃,which is matched with that of othercurrent multi-channel statistical methods(0.5—1.36℃).The retrieval SST distributions obtainedby the two methods are in good agreement with conventional observations.     

GMS-5 估计可降水量的研究

文章证明了由静止气象卫星GMS-5的分裂窗通道和水汽通道亮温反演可降水量的可行性,探讨了GMS-5红外通道亮温与可降水量的关系,建立了由3个通道亮温反演可降水量的经验公式。用60组大气平均廓线,对公式模拟检验误差为0.18 g/cm2,而用实际124组探空和对应的GMS-5亮温资料进行检验,误差0.40 g/cm2。用得到的经验公式可反演大范围的晴空可降水量分布。     

用应用需求数据库评估卫星观测能力

卫星应用需求分析是气象卫星规划和研制十分关键的第一步。为了搞好21世纪的全球气象卫星发展规划,WMO和CEOS从1996年开始征集全球对地观测卫星的应用需求和建立卫星需求数据库,创立了国际通行的RRR程序方法,建立了全球对地观测卫星应用需求数据库。文章介绍了WMO/CEOS卫星应用需求数据库的RRR程序方法和数据库的部分内容,着重介绍和评述了建立卫星应用需求数据库以及基于卫星需求数据库进行卫星观测能力定量评估的方法,为中国气象卫星应用需求数据库的建设创造有利条件。     

HUBEX试验期间地基微波辐射计反演资料的应用研究

在1998年和1999年淮河流域能量和水循环试验(HUBEX)加密观测期间(IOPs),获得了双通道微波辐射计观测资料反演得到的大气水汽含量和云中液态水含量的时间连续资料序列.本文结合天气分析和其他加密观测资料,进行了HUBEX试验期间天气变化同大气水分变化关系的分析.结果表明,天气条件的变化是大气水分变化的主要原因.     

用GMS-5卫星资料结合地面资料联合估算水汽分布

利用GMS-5卫星红外分裂窗通道和水汽通道结合探空资料反演晴空大气的水汽分布;同时利用探空资料建立地面水汽压和相对湿度与大气总水汽量的经验关系,通过带权插值生成淮河流域300多个地面站经验关系式的系数矩阵,并利用地面站资料确定云天大气的水汽分布.最后,将两种方法进行融合,得到淮河流域全天候的水汽场分布.     

ANALYSIS ON CHARACTERISTICS OF ATMOSPHERIC DUCT AND ITS EFFECTS ON THE PROPAGATION OF ELECTROMAGNETIC WAVE

On the basis of introducing the basic categories of atmospheric refraction and their existingconditions,the forming processes of three kinds of atmospheric ducts are expounded.Several maincharacteristics of atmospheric duct are summarized and analyzed,and field sounding data from theWEstern North-Pacific cloud-radiation EXperiment(WENPEX)and meteorological data aroundthe Xisha sea area are used to validate these characteristics.Meanwhile the sensitivities of theevaporation duct height to the variations of atmospheric humidity.the air-sea temperaturedifference.and horizontal wind speed are examined.With the analysis of the effect of atmosphericduct on the propagation of electromagnetic wave.the maximum trapped-wavelength and the criticalemitting angle of elevation for electromagnetic wave which can form duct propagation are derived.At the same time the four kinds of necessary conditions for electromagnetic wave to form ductpropagation are brought forward.The effects of atmospheric duct on ultrashort wave propagation,radar observation.short wave communication etc.are also discussed.     

用卫星遥感资料反演气象参数的误差分析及数值试验

首先从理论分析入手，定性地探讨了用气象卫星遥感探测辐射测值反演气象参数的误差特性，进而用同步物理反演法进行了反演误差的数值试验，定量地揭示了反演误差的来源及特性。这些理论分析和数值试验对设计遥感系统、提高反演精度等都具有一定的指导意义。     

ATOVS辐射率资料的直接变分同化试验研究

文中采用增量三维变分 ( 3D Var)同化方法 ,对先进的微波探测装置 (AMSU A)探测的辐射亮温资料与常规探空资料在MM5中尺度数值预报模式中的直接同化和预报进行对比试验研究。结果表明 ,同化AMSU A辐射亮温资料对中高层温度分析场的影响最明显 ,对MM5模式的温度和水汽混合比预报有总体上的正效应 ,但对降水预报的改善作用不大