Air Temperature Estimation with MODIS Data over the Northern Tibetan Plateau     

Fangfang HUANG  Weiqiang MA  Binbin WANG  Zeyong HU  Yaoming MA  Genhou SUN  Zhipeng XIE  Yun LIN 《大气科学进展》2017,34(5):650-662

Time series of MODIS land surface temperature(T_s) and normalized difference vegetation index(NDVI) products,combined with digital elevation model(DEM) and meteorological data from 2001 to 2012,were used to map the spatial distribution of monthly mean air temperature over the Northern Tibetan Plateau(NTP). A time series analysis and a regression analysis of monthly mean land surface temperature(T_s) and air temperature(T_a) were conducted using ordinary linear regression(OLR) and geographical weighted regression(GWR). The analyses showed that GWR,which considers MODIS T_s,NDVI and elevation as independent variables,yielded much better results [R_(Adj)~2 0.79; root-mean-square error(RMSE) =0.51℃–1.12℃] associated with estimating T_a compared to those from OLR(R_(Adj)~2= 0.40-0.78; RMSE = 1.60℃–4.38℃).In addition,some characteristics of the spatial distribution of monthly T_a and the difference between the surface and air temperature(T_d) are as follows. According to the analysis of the 0℃ and 10℃ isothermals,T_a values over the NTP at elevations of 4000–5000 m were greater than 10℃ in the summer(from May to October),and T_a values at an elevation of3200 m dropped below 0℃ in the winter(from November to April). T_a exhibited an increasing trend from northwest to southeast. Except in the southeastern area of the NTP,T d values in other areas were all larger than 0℃ in the winter.  相似文献   

GIS及其在三高农业规划中的应用初探   总被引：2，自引：0，他引：2  

张伟强  邹春洋 《热带地理》1997,17(4):354-358

本文简要介绍了地理信息系统（ＧＩＳ）的基本概念及功能,并尝试把ＰＣ ＡＲＣ／ＩＮＦＯ应用于三高农业规划。通过实例应用,认为ＧＩＳ在三高农业规划及管理方面具有广阔的应用前景。  相似文献   

Experimental Study on the Thermal Damage Characteristics of Limestone and Underlying Mechanism     

Weiqiang Zhang  Qiang Sun  Shuqing Hao  Bo Wang 《Rock Mechanics and Rock Engineering》2016,49(8):2999-3008

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毛乌素沙地中部风成沙的组成与微形态特征   总被引：5，自引：5，他引：0  

陈国祥  董治宝  崔徐甲  肖巍强  李露露  杨军怀  石唯康 《中国沙漠》2018,38(3):473-483

分析了毛乌素沙地中部流动沙丘与固定-半固定沙丘沉积物粒度、元素和微形态特征。结果表明：流动沙丘沙和固定-半固定沙丘沙均以细沙和中沙为主,流动沙丘沙的分选性较好,而固定-半固定沙丘沙的分选性较差,沙丘在频繁强烈的风沙活动环境下跃移搬运,且搬运方式一定,搬运动力稳定。与上部陆壳平均化学组成（UCC）相比,常量元素SiO₂和Na₂O富集,其余均亏损,而微量元素中,Co富集明显。沙丘沙物质CIA值与上部陆壳平均值接近,表明沙丘经历了低等的化学风化。流动沙丘和固定-半固定沙丘颗粒磨圆度普遍较差,大多呈现棱角状或次棱角状外形,真正圆状外形较少。风成环境的典型标志碟形撞击坑占比很大,推断毛乌素沙地中部气候相对干燥,机械作用占主导地位,化学风化作用甚微。  相似文献   

The variation of marine environment and climate effect in Indo-Pacific Ocean     

Zuo  Juncheng  Wang  Weiqiang  Wang  Guihua  Xie  Qiang 《中国海洋湖沼学报》2020,38(6):1599-1601

Journal of Oceanology and Limnology -  相似文献   

基于网络地图服务的MS Office地图插件设计与实现     

周伟强  成毅  郭建忠  祝若鑫 《测绘科学技术学报》2016,(2):215-220

随着地理信息应用的广泛深入,网络地图服务的嵌入式应用技术研究受到越来越多的重视。MS Office系列软件作为最常用的办公软件平台,具备强大的文字处理功能,但是对地理信息服务的支持有很大不足。用户在Office中表达地理信息一般借助于其他软件并作为图片嵌入文档中。针对这一问题,结合网络地理信息服务技术,研究了基于MS Office软件平台的地图插件设计方案。实现了一个能够在Office软件中直接使用地图服务的第三方Plug-In插件,通过实验验证了该插件的可行性和有效性。  相似文献   

手持农田面积测量终端研制     

董康  刘文国  孟志军  付卫强  武广伟 《测绘地理信息》2022,47(3):91-95

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2013年3月20日广东东莞罕见龙卷冰雹特征及成因分析   总被引：1，自引：0，他引：1  

张劲梅  莫伟强 《湖北气象》2013,(4):330-337

利用常规观测、NCEP/NCAR再分析、多普勒天气雷达及自动气象站资料等,对2013年3月20日发生在东莞的一次罕见龙卷、冰雹等致灾性强对流天气过程进行分析。结果表明：1）龙卷过境时的单站气压、温度、风向风速与雷雨大风过境时明显不同,前者具有较典型的龙卷特征。2）华南地区高低空强的风随高度增大的垂直变化、上干下湿的位势不稳定层结以及低层高湿、增温为对流天气发展提供了有利的环境条件,冷空气南压和近地面边界层中小尺度辐合系统为其提供了触发机制。3）中等强度的对流有效位能（CAPE）、强的0-6 km深层垂直风切变以及较强的0-1 km低层垂直风切变为龙卷产生提供了可能性。4）龙卷、冰雹强对流风暴的发展加强与近地面边界层中小尺度辐合系统加强有密切关系。5）同时出现冰雹、大风、龙卷时,最强回波为72 dBz;龙卷出现在超级单体的钩状回波附近,更靠近后侧V形缺口;多时次观测到三体散射（TBSS）回波,与降雹对应;反射率垂直剖面图上可见明显的低层弱回波区、中高层回波悬垂,有界弱回波区（BWER）先于龙卷20多分钟出现。径向速度图上,龙卷出现时超级单体风暴同时具有龙卷涡旋特征（TVS）和中气旋特征。  相似文献   

Evaluation of SEBS for estimation of actual evapotranspiration using ASTER satellite data for irrigation areas of Australia   总被引：2，自引：0，他引：2  

Weiqiang Ma  Mohsin Hafeez  Hirohiko Ishikawa  Yaoming Ma 《Theoretical and Applied Climatology》2013,112(3-4):609-616

Spatial knowledge of land surface evapotranspiration (ET) is of prime interest for environmental applications, such as optimizing irrigation water use, irrigation system performance, crop water deficit, drought mitigation strategies, and accurate initialization of climate prediction models especially in arid and semiarid catchments where water shortage is a critical problem. The recent drought in Australia and concerns about climate change have highlighted the need to manage water resources more sustainably especially in the Murrumbidgee catchment which utilizes bulk water for food production. This study deals with the application of a Surface Energy Balance System (SEBS) algorithm based on Advanced Spaceborne Thermal Emission and Reflection radiometer (ASTER) data and field observations has been proposed and tested for deriving ET over Coleambally Irrigation Area, located in the southwest of NSW, Australia. We have used 12 ASTER scenes covering the time period of 2002, 2003, 2004, 2005, 2006, and 2009 for estimating the actual ET over the study area. To validate the proposed methodology, the ground-measured ET was compared to the ASTER-derived actual ET values for the study area. The derived ET value over the study area is much closer to the field measurement. From the remote sensing results and observations, the root mean square error is 0.89 and the mean absolute percentage difference is 2.87 %, which demonstrate the reasonability of SEBS ET estimation for the study area.  相似文献   

Comparison of airsea fluxes of CO₂ in the Southern Ocean and the western Arctic Ocean   总被引：1，自引：0，他引：1  

CHEN Liqi  GAO Zhongyong  YANG Xulin  WANG Weiqiang 《海洋学报(英文版)》2004,23(4):647-653

The data were collected during Chinese Arctic and Antarctic Expeditions in the western Arctic Ocean and the marginal sea ice zone (MSIZ) of the Southern Ocean, respectively in the boreal summer from July to September of 1999 and in the austral summer from December of 1999 to January of 2000. The concentrations of CO2 in surface water of the survey regions would mostly present lower than those in the atmosphere. A significant biological driving force could also been observed in summer waters in both of the above oceans. Air to sea CO2 fluxes were also calculated to compare oceanic uptake capacity of CO2 in both oceans with the world oceans using Liss, Wanninkhof, and Jacobs‘s methods. The averaged CO2 fluxes of air to sea in the western Arctic Ocean or in the MSIZ of the Southern Ocean doubled that in the world oceans.  相似文献