APPLICATION OF NONLINEAR MULTI-CHANNEL ALGORITHMS FOR ESTIMATING SEA SURFACE TEMPERATURE WITH NOAA 14 AVHRR DATA   总被引：1，自引：0，他引：1  

李晓峰 《中国海洋湖沼学报》2000,18(3):199-207

ＩＮＴＲＯＤＵＣＴＩＯＮＳｉｎｃｅｔｈｅｅａｒｌｙ 1 970ｓ,ｔｈｅＡｄｖａｎｃｅｄＶｅｒｙＨｉｇｈＲｅｓｏｌｕｔｉｏｎＲａｄｉｏｍｅｔｅｒ(ＡＶＨＲＲ)ｏｎｂｏａｒｄｔｈｅＮａｔｉｏｎａｌＯｃｅａｎｉｃａｎｄＡｔｍｏｓｐｈｅｒｉｃＡｄｍｉｎｉｓｔｒａｔｉｏｎ (ＮＯＡＡ)ｓｅｒｉｅｓｏｆＰｏｌａｒ ｏｒｂｉｔｉｎｇＯｐｅｒａｔｉｏｎａｌＥｎ ｖｉｒｏｎｍｅｎｔａｌＳａｔｅｌｌｉｔｅｓ (ＰＯＥＳ)ｈａｓｂｅｅｎｕｓｅｄｆｏｒｓｅａｓｕｒｆａｃｅｔｅｍｐｅｒａｔｕｒｅ (ＳＳＴ)ｒｅｔｒｉｅｖａｌａｎｄｃｌｏｕ…  相似文献   

Long-term monitoring using resident and caged mussels in Boston Harbor yield similar spatial and temporal trends in chemical contamination     

Carlton D. Hunt  Elizabeth Slone 《Marine environmental research》2010,70(5):343

Measurements of chemical contaminants in caged (transplanted) and resident mussel populations have become a routine tool for monitoring and assessing the status and trends of coastal water quality. However, few long-term data sets are available to assess the comparability and efficacy of these two monitoring approaches. Three long-term independent data sets exist for Boston Harbor: the National Mussel Watch program has analyzed resident blue mussels (Mytilus edulis) from the Boston Harbor/Massachusetts Bay region for over twenty years, the Massachusetts Water Resources Authority has annually deployed caged (transplanted) mussels (M. edulis) to assess bioaccumulation potential of sewage effluent discharged under its NPDES permit for over fourteen years, and the GulfWatch program has analyzed resident blue mussel populations for over twelve years. Together, these data provide consistent and comparable information on temporal and spatial changes in chemical contamination in Boston Harbor as steps were taken to reduce contaminant loading. The data also demonstrate the complementary nature of resident and caged (transplanted) mussels for assessing contaminant trends even when the basic approaches and sampling frequency differ. These fifteen-year data sets demonstrate contaminant concentrations in mussels from Boston Harbor are similar and with few exceptions have significantly decreased since the early 1990s. The observed trends also demonstrate broad scale improvements to the quality of Boston Harbor and expand understanding of the response of coastal systems to interventions that reduce the load of chemicals to the ocean.  相似文献   

“百合”台风对海表温度及水色环境影响的遥感分析     

付东洋  丁又专  雷惠  潘德炉 《海洋学研究》2009,27(2):64-70

利用SeaWiFS及NOAA卫星资料,基于均值合成算法,分析了"百合"台风对海表温度(SST)、海表叶绿素a浓度及海水透明度的影响,结果表明,整个研究海域(22°～30°N、121°～131°E)的平均SST从台风前的25.48℃下降到22.45℃,平均下降幅度为12.95%.在台风盘旋的中心区域(26°～28°N、123°～127°E),SST平均下降了5.40℃,下降幅度达21.20%,SST下降最大的是9月14日,整个研究海域平均SST仅为13.48℃.整个研究海域海表叶绿素a浓度在台风期间有较大的增加,从台风前的0.425 mg/m3(平均值)上升到0.537 mg/m3,平均增长26.35%.除浙江近海外,台风核心区域海表叶绿素a浓度增幅最大,达1.695倍,表明台风风力越强,台风停留时间越长,对海表叶绿素a浓度增加的贡献就越大.这一增加有利于海洋生物的生长,有利于提高初级生产力和改善海洋生态环境.在"百合"台风期间,海水透明度却有一定程度的降低,从台风前的16.84 m(平均值)下降至台风后的12.67 m,平均降幅为24.76%,降幅最大的是24°～26°N、125°～127°E区块,平均下降了7.96 m,降幅高达47.6%;总体上台风核心区域南部的海水透明度降幅大于区域北部,台风核心区域东南部的海表叶绿素a浓度增幅大于区域东北部.同时,对整个研究海域分割成2°×2°大小的区块,以每个区块的海表叶绿素a浓度、SST和海水透明度的均值代表该区块的值,对台风前、后海表叶绿素a浓度、SST和海水透明度的变化进行相关性分析,发现海表叶绿素a浓度的变化与SST和海水透明度均呈负相关性,且台风期间海表叶绿素a浓度增加的百分比与相应区块海水透明度下降的百分比之间的相关系数达0.821.  相似文献   

基于NOAA/AVHRR卫星资料的北京地区霾识别研究   总被引：1，自引：1，他引：0  

刘勇洪 《气象》2014,40(5):619-627

利用2008—2013年NOAA/AVHRRlB卫星资料和气象观测资料,应用米氏散射理论、图像色彩处理技术、频数分布图和可见光通道表观反射率阈值技术,开展了北京地区霾的遥感识别研究,并在京津冀地区进行了应用。研究结果表明:易于识别的霾在NOAA/AVHRR遥感图像上一般以1、2、1波段或4、2、1波段进行红、绿、蓝三通道假彩色合成.图像颜色以灰色、紫色和蓝色三大系列为主;一般仅靠遥感图像难以识别霾与轻雾,但借助先验知识、周围环境和图像色彩.可在一定程度上区分霾与轻雾;NOAA/AVHRR图像的第一波段表观反射率作为光谱指标可以对霾进行较好识别,反射率识别指标值分别为:冬季0.15～0.32,春季0.15～0.30,夏季0.14～0.30,秋季0.14～0.32;指标对霾的有效识别准确率为82%。利用上述建立的颜色指标和光谱指标可以较好地对2013年1—3月发生在京津冀地区的雾霾进行有效监测。  相似文献   

Long-term variability in Arctic sea surface temperatures     

Rajkumar Kamaljit Singh  Megha Maheshwari  Sandip R. Oza  Raj Kumar 《Polar Science》2013,7(3-4):233-240

In this study, we used 30 years of an operational sea surface temperature (SST) product, the NOAA Optimum Interpolation (OI) SST Version 2 dataset, to examine variations in Arctic SSTs during the period December 1981–October 2011. We computed annual SST anomalies and interannual trends in SST variations for the period 1982–2010; during this period, marginal (though statistically significant) increases in SSTs were observed in oceanic regions poleward of 60°N. A warming trend is evident over most of the Arctic region, the Beaufort Sea, the Chuckchi Sea, Hudson Bay, the Labrador Sea, the Iceland Sea, the Norwegian Sea, Bering Strait, etc.; Labrador Sea experienced higher temperature anomalies than those observed in other regions. However, cooling trends were observed in the central Arctic, some parts of Baffin Bay, the Kara Sea (south of Novaya Zemlya), the Laptev Sea, the Siberian Sea, and Fram Strait. The central Arctic region experienced a cooling trend only during 1992–2001; warming trends were observed during 1982–1991 and 2002–2010. We also examined a 30-yr (1982–2011) record of summer season (June–July–August) SST variations and a 29-yr (1982–2010) record of September SST variations, the results of which are discussed.  相似文献   

Estimation of Surface Temperature and Rainfall in Ghana     

V. C.K. Kakane  H. Søgaard 《Geografisk tidskrift / udgivet af Bestyrelsen for Det Kongelige danske geografiske selskab》2013,113(1):76-85

Geografisk Tidsskrift, Danish Journal of Geography 97: 76–85, 1997.

Daily Meteosat images for 1989 have been analysed for the purpose of mapping surface temperature and rainfall in Ghana. The images in the time-series are georeferenced and the maximum value composite (MVC) technique is applied to the temperature calibrated IR-channel images after a cloud screening of the images. The cloud covered areas are outlined and traced using the Meteosat visible channels. Stratiform clouds are detected using surface albedo while cumuliform clouds are detected based on a technique calculating the spatial variability within a 5 pixel by 5 pixel window around each point in the image. The cloud covered parts of the scene are then delimitated by comparing the normal albedo values and the spatial variance in albedo.

The paper then discusses how the outlined procedure can be applied in an environmental monitoring context. For each of the months June to November 1989 the mean monthly rainfall amounts at 35 meteorological stations are plotted against the mean surface temperature. It is found that apart from the month of June statistical significant linear relationships are obtained and that the scattering around the line is decreasing for increasing sampling length.  相似文献   

AMSU温度反演及其在台风研究中的应用   总被引：1，自引：1，他引：1  

魏应植  许健民 《南京气象学院学报》2005,28(4):522-529

利用物理统计综合方法，建立了统计回归模型，作AMSU（Advanced Microwave Sounding Unit）温度反演。采用Liebe模式计算了AMSU3～14通道微波波段的权重函数，利用计算得到的归一化权重函数作为统计回归模型的约束夸件，并适当调整约束因子求得方程的最佳解。结果表明，当采用近星下点的AMSU—A亮温资料样本时，该算法模型具有较高的反演精度，在100hPa以下，温度均方根偏差为0．4K，100hPa及以上的均方根偏差为1．0K。用同样的约束回归算法对AMSU偏离星下点的观测视场作了临边订正，对于通道4～14（频率52．8～57．29GHz）的大气探测通道，使其最大偏差由-15～5K减小为4-0．9K。利用反演的温度，对2002-2003年登陆和影响我国的15个热带气旋的暖心结构作了分析，发现AMSU温度不仅能够清晰地反映热带气旋的暖核结构，而且其温度距平值与热带气旋中心风速和最低海平面气压有较好的相关关系，对实际分析预报有一定的参考价值：  相似文献   

AUTO-IDENTIFICATION OF FOREST FIRE-POINTS IN NOAA IMAGES BASED ON NEURAL NETWORK     

LIANG Yitong HU Jianglin LIU Liangming XIE Ping 《地球空间信息科学学报》2001,4(3):68-72

1　ＩｎｔｒｏｄｕｃｔｉｏｎＴｈｅｉｄｅｎｔｉｆｉｃａｔｉｏｎｏｆｆｏｒｅｓｔｆｉｒｅ＿ｐｏｉｎｔｓｉｎＮＯＡＡｉｍａｇｅｓｉｓｔｈｅｂａｓｉｓｏｆｍｏｎｉｔｏｒｉｎｇｆｏｒｅｓｔｆｉｒｅｕｓｉｎｇＮＯＡＡｓａｔｅｌｌｉｔｅｄａｔａ .Ｔｈｅｔｒａｄｉｔｉｏｎａｌａｐｐｒｏａｃｈｏｆｉ ｄｅｎｔｉｆｉｃａｔｉｏｎｉｓｖｉｓｕａｌｉｎｔｅｒｐｒｅｔａｔｉｏｎ .Ｂｙｔｈｅｖｉｓｕａｌｉｎｔｅｒｐｒｅｔａｔｉｏｎ ,ｂｅｔｔｅｒｐｒｅｃｉｓｉｏｎｉｓｏｂｔａｉｎｅｄｉｎｐｒａｃ ｔｉｃｅ,ｂｕｔｅｘｐｅｒｉｅ…  相似文献   

NOAA卫星资料云雪识别方法的研究   总被引：3，自引：3，他引：3  

殷青军  杨英莲  徐维新 《高原气象》2002,21(5):526-528

通过分析NOAA／AVHRR资料中云和雪的光谱特征，在已有的研究成果基础上做了大量的试验分析。针对青海省南部(以下简称青南)的云、雪特征，提出了新的云、雪判别因子，对于区分青南地区的云、雪有较好的效果。  相似文献   

大型水体在干旱遥感监测业务中的应用   总被引：3，自引：0，他引：3  

李亚春  徐萌  孙涵 《气象》2002,28(7):26-28

应用NOAA极轨气象卫星AVHRR资料，通过遥感图像分析和计算洪泽湖、高邮湖、骆马湖以及微山湖等大型河湖水体面积的变化，来监测苏北干旱的发生、发展和旱情严重程度，并及时应用于气象业务和服务中，取得了较好的社会经济效益。  相似文献