SPATIO-TEMPORAL VARIATION OF ACTUAL EVAPOTRANSPIRATION AND ITS RELATION WITH CLIMATE PARAMETERS IN THE PEARL RIVER BASIN, CHINA     

吴萍  李修仓  苏布达  占明锦  王艳君  姜彤 《热带气象学报(英文版)》2017,23(1):81-90

Spatio-temporal variation of actual evapotranspiration (ETa) in the Pearl River basin from 1961 to 2010 are analyzed based on daily data from 60 national observed stations. ETa is calculated by the Advection-Aridity model (AA model) in the current study, and Mann–Kendall test (MK) and Inverse Distance Weighted interpolation method (IDW) were applied to detect the trends and spatial variation pattern. The relations of ETa with climate parameters and radiation / dynamic terms are analyzed by Person correlation method. Our findings are shown as follows: 1) Mean annual ETa in the Pearl River basin is about 665.6 mm/a. It has significantly decreased in 1961–2010 at a rate of -24.3 mm/10a. Seasonally, negative trends of summer and autumn ETa are higher than that of spring and winter. 2) The value of ETa is higher in the southeast coastal area than in the northwest region of the Pearl River basin, while the latter has shown the strongest negative trend. 3) Negative trends of ETa in the Pearl River basin are most probably due to decreasing radiation term and increasing dynamic term. The decrease of the radiation term is related with declining diurnal temperature range and sunshine duration, and rising atmospheric pressure as well. The contribution of dynamic term comes from increasing average temperature, maximum and minimum temperatures in the basin. Meanwhile, the decreasing average wind speed weakens dynamic term and finally, to a certain extent, it slows down the negative trend of the ETa.  相似文献   

辽宁地区暖区和锋面暴雨个例对比分析   总被引：1，自引：1，他引：0  

吴晓锋  王元  徐昕  吕童  聂安祺 《气象科学》2017,37(5):700-708

2013年7月1—2日,辽宁地区出现了持续时间较长的暴雨天气过程,此次过程可以分为3个阶段,其中包括两次暖区降水和一次冷锋锋面与暖区降水共存的过程,第一阶段的暖区降水和第三阶段的锋面降水形成了西北雨带,第二阶段的暖区降水形成了东南雨带。利用NCEP再分析资料、常规自动站观测资料、加密自动站观测资料和卫星资料,详细分析了此次过程中各阶段降水产生的机制以及锋面降水和暖区降水的主要物理差异。结果表明:暖区强降水主要出现在干线冷湿气团一侧或地面辐合线附近,并且由于暖区高温、高湿的特点,其产生的降水通常比锋面附近强,同时暖区降水与锋面降水在触发机制、中尺度环境条件、动力、热力结构等方面也存在着差异。  相似文献   

一次海风锋天气过程分析与数值模拟     

童志明  施萧  冯箫 《气象与环境科学》2017,40(2):109-114

利用NCEP再分析资料、自动气象站观测数据、多普勒天气雷达反射率因子和WRF模式,对2015年5月24日午后,海南岛东北部出现的一次较强的海风锋降水天气进行过程分析和数值模拟。结果表明:强降水发生期间,海南岛处于副热带高压边缘,中低层水汽来源充沛,降水前后K指数变化明显;两支分别来自海口海岸线向东南移动与来自文昌海岸线向西北移动的海风锋的发展、增强与移动,是导致本次降水的主要原因。另外,中部山区小尺度的地形辐合有利于过程期间海风锋的加强与发展;WRF模式的模拟结果说明,海风锋发展最旺盛的时候,锋面高度达约1000 m,宽度约0.15个经度;海风锋垂直环流圈的建立伴随着地面降水的加强;地面降水减弱时,海风锋环流圈逐渐消失。  相似文献   

不同甾醇类物质对河蟹眼柄神经分泌细胞ICa的影响   总被引：1，自引：4，他引：1  

孙金生  刘安西  贺秉军  陈家童  相建海 《海洋与湖沼》2001,32(6):627-634

采用膜片钳技术测定了不同甾醇类物质对河蟹眼柄视神经节端髓X器官(MTXO)神经分泌细胞钙离子通道电流(ICa)的作用,探讨河蟹眼柄神经肽类激素分泌和养殖河蟹性早熟的调控机制.结果表明,河蟹眼柄MTXO三种类型神经分泌细胞均表达高电压激活L型钙通道,激活电压为-30mV,+10mV达到峰值.甾醇类物质中,只有胆固醇对河蟹眼柄B型神经内分泌细胞的钙电流存在抑制作用,其作用具有浓度依赖性,抑制强度不随时间的延长而加强.1μmol/L的胆固醇作用4h可抑制B型细胞50.49%±5.98%的钙电流.  相似文献   

准噶尔盆地沙漠区地震检波器耦合研究     

徐淑合  刘怀山  童思友  付大志 《中国海洋大学学报(自然科学版)》2003,33(5):783-790

通过对检波器耦合理论研究 ,根据沙漠区的地震环境和地表结构 ,设计出了不同类型的检波器耦合装置 ,增加了检波器与沙漠地表的耦合性能。从野外进行对比试验资料分析 ,在沙漠区地震检波器耦合具有高分辨率、抗干扰、耦合性好、适应领域广等特性 ,接收的地震信号能量、优势信噪比频带宽度和信号保真度等方面均有明显提高 ,将从根本上解决沙漠区高分辨率和深层地震勘探的难题。  相似文献   

Space-Time Characteristic Analysis of Wind Field over the South Indian Ocean     

佟凯  刘金芳  闫明  李颜  杨亮 《海洋通报(英文版)》2003,5(2):5-13

1 IntroductionThe South Indian Ocean is the only way which must be passed in marine traffic among Africa, Asia and Oceania. With the development of the international traffic, it becomes more and more frequent to navigate over the South Indian Ocean. More and more hydrometeorological safeguards especially the safeguards of important cruise lines are required. However, data for the region in China is absent except the Indian Ocean Climate Atlas (1973)[1] which has short fixed number of…  相似文献   

用基因枪将GUS基因导入褐藻细胞中表达   总被引：18，自引：2，他引：18  

秦松  张健  李文斌  王希华  童顺  孙勇如  曾呈奎 《海洋与湖沼》1994,25(4):353-356

于１９９３年１１月－１９９４年２月，用高压氦气式基因枪，将ＰＨ１２２１质粒装有ＧａＭＶ ３５Ｓ启动子，ＧＵＳ基因以及ｎｏｓ的３＇调控区导入海带和裙带菜组织切块中。４８ｈ后，在海带假根细胞和裙带菜中肋部叶片细胞中检测到ＧＵＳ基因的表达。实验表明，微粒子轰击法是外源基因导入大型褐藻的一个有效途径。ＧａＭＶ ３５Ｓ启动子能够驱动外源基因在海洋藻类中的表达，可作为藻类基因工程的启动元件。  相似文献   

A Model for Loadout Analysis and Its Programming Implementation     

Zhong Wanxie  Yao Shizhong Wu Lianyuan  Xi Deyin Professor  Shanghai Jiao Tong University    Shanghai Engineer  Shanghai Jiao Tong University    Shanghai Lecturer  Shanghai Jiao Tong University.  Shanghai 《中国海洋工程》1993,(4)

- In this paper, the authors use the finite element method to conduct a special static analysis for the loadout procedure of offshore structures. By introducing a variable Xmove (the distance between the relative coordinate system fixed in the moving upper structure and the absolute coordinate system fixed on slideway), adopting substructure to treat the upper structure, and using the elastic foundation beam to model the slideway, the model for the analysis of the loadoul procedure is established. On the basis of this model, DASOS-J loadout program, a program system for the static analysis of loadout offshore structures, is also developed.  相似文献   

Glacier changes since the early 1960s,eastern Pamir,China   总被引：2，自引：0，他引：2  

Zhen Zhang  Jun-li Xu  Shi-yin Liu  Wan-qin Guo  Jun-feng Wei  Tong Feng 《山地科学学报》2016,13(2):276-291

Glaciers in the eastern Pamir are important for water resources and the social and economic development of the region.In the last 50 years,these glaciers have shrunk and lost ice mass due to climate change.In order to understand recent glacier dynamics in the region,a new inventory was compiled from Landsat TM/ETM+ images acquired in2009,free of clouds and with minimal snow cover on the glacierized mountains.The first glacier inventory of the area was also updated by digitizing glacier outlines from topographical maps that had been modified and verified using aerial photographs.Total glacier area decreased by 10.8%±1.1%,mainly attributed to an increase in air temperature,although precipitation,glacier size and topographic features also combined to affect the general shrinkage of the glaciers.The 19.3–21.4 km~3 estimated glacier mass loss has contributed to an increase in river runoff and water resources.  相似文献   

长白山自然保护区生态环境质量的遥感评价   总被引：1，自引：0，他引：1  

王士远  张学霞  朱彤  杨维  赵静瑶 《地理科学进展》2016,35(10):1269-1278

人类的生存质量与生态环境密切相关,利用遥感技术可快速地进行生态环境质量评价,为区域生态环境的治理、改善以及发展规划提供重要参考。本文以长白山自然保护区为例,选取1995、2007年Landsat5 TM影像和2015年Landsat8 OLI影像,反演得到能反映生态环境的绿度、湿度、热度和干度等指标,利用主成分分析法,依据新型遥感生态指数RSEI对长白山自然保护区1995-2015年的生态环境进行评价,结果表明：①绿度、湿度指标对区域生态环境起正向作用,热度、干度指标对区域生态环境起负向作用,且湿度对生态环境影响较大;②该区域1995、2007、2015年生态指数优良等级所占比例依次为49.520%、66.508%、76.189%,同时RSEI等级变差、不变、变好的比例分别为3.945%、55.598%、40.457%。生态环境质量整体不断改善,说明长白山自然保护区的天然林资源保护工程以及一系列生态保育措施起到了一定作用;而天池周边生态环境质量有所下降可能与旅游活动的快速发展有关;③逐步回归分析的结果表明,所选的各指标均为指示生态环境质量的关键指标;而裸露、干化地表的治理则是改善生态环境质量的关键。  相似文献