渤海海冰开采对渤海周边地区冬季气候影响的数值试验

本文利用2005年1月15日到2月14日 NCEP 再分析资料和 MODIS 卫星反演海冰分布资料及中尺度大气模式 POLAR MM5 对 2005 年冬季渤海区域进行气候模拟.根据 MODIS 卫星反演海冰资料,对模式运行区域下垫面的渤海海冰进行不同方案的开采,模拟其对渤海及周边地区冬季气候的影响.结果表明即使采取极端开采方案取走所有海冰,也只对开采区域和大连少部分地区冬季气候有所影响,而对我国其他邻海省份的气候环境没有明显的影响.     

渤海的海冰数值预报

根据渤海气候和冰情特点,在已有海冰模式研究基础上,提出模拟海冰增长、消融和漂移的动力－热力学模式。模式冰厚分布由开阔水、平整冰和堆积冰三要素表示。该模式已与数值天气预报模式、大气边界层模式、潮流模式联结,并于１９９０年到１９９６年在国家海洋环境预报中心进行渤海和北黄海冰情预报。其数值预报产品包括冰厚、密度集、冰速、冰外缘线、冰脊参数、局地冰厚以及接近石油平台的冰漂移轨迹等,传送到国家海洋预报台和渤海石油公司等有关用户。为了客观评价模式和检验预报结果,在逐日预报后进行统计检验。本文概述渤海冰情、卫星遥感应用、冰模式及其预报结果和检验。     

EOS/MODIS数据在广西甘蔗种植信息提取及面积估算的应用

通过计算广西区域多时相MODIS-NDVI值,结合GPS选定甘蔗样本训练区多时相NDVI值变化曲线,以及甘蔗生长周期长达8个月至1年以上,蔗糖生产期间甘蔗面积逐渐递减的特性,采用最大似然法提取非样本训练区甘蔗种植信息,最终实现广西区域的甘蔗种植空间分布遥感信息的提取。经对遥感影像图甘蔗连片种植区域、零散点种植区与GPS实地定位调查比较,结果表明广西区域甘蔗种植信息遥感监测与实况相符。在此基础上,对广西区域甘蔗种植面积估算面积进行初步统计,精度达到90%以上。     

渤海海冰数值模式的研究进展

根据渤海海冰冰情,从热力和动力两个方面综述了渤海海冰数值模式的研究进展。从热力参数方案和气候特点上,展望新一代渤海中小尺度短期海冰热力模式;从海冰动力模式中3种常用数值方法的主要特点和实际应用情况上,论述SPH(Smoothed Particle Hydrodynamics)方法在渤海海冰短期预报的发展前景。在此基础上,结合海洋气象的发展,讨论海冰短期预报的关键技术。将海冰数值预报模式与传统的中长期海冰统计预报有机地结合起来将是渤海海冰模式未来的发展方向。     

渤海海冰单点模式的气候模拟

利用PW1979海冰热力模式，考虑渤海的地理特点和气候特征，假设渤海为薄层海洋，引入二分法求解海冰表面温度。用该地区气候平均的云量、湿度、海平面气压和风速以及附近4站的月平均气温资料作为强迫场，模拟了渤海海冰的气候变化。模拟结果与逐年的海冰级数资料具有一致的变率，表明气温对海冰年际变化有重要影响。     

长时间序列卫星遥感渤海海冰时空分布特征及与气温关系分析

利用气象卫星资料整理分析了1996—2011年冬季渤海海冰的时空分布变化:年际统计表明,单日海冰面积最大的3个年份分别是2011、2010和2001年,日最大冰面积均超过30000 km~2;单日海冰面积最小的3个年份分别是1999、2002和2007年,日最大冰面积均不超过10000 km~2。分区统计显示,海冰主要集中在辽东湾,其次是渤海湾,莱州湾最小;辽东湾海冰从东北向西南、从海滨到远海出现频率依次降低;渤海湾和莱州湾从海滨到远海,海冰的出现频率逐渐降低。在此基础上,分析了渤海逐日冰面积与营口站日均气温积温(≤-2℃)及气温的关系,结果表明渤海逐日冰面积与积温、气温之间均为负相关关系,其相关性在不同阶段表现不同:海冰发展期,渤海逐日冰面积与营口日均气温积温(≤-2℃)之间的相关性最为显著,相关系数为-0.90;海冰消融期,渤海逐日冰面积与营口3日(当日与前两日)平均气温的相关性最为显著,相关系数为-0.84;通过回归分析方法获得了渤海逐日冰面积与营口日均气温积温及3日平均气温的线性回归方程。最后,结合积温回归方程和3日平均气温回归方程,提出了分阶段的海冰面积预报方程,并利用该方程对2013和2014年度冬季渤海冰面积进行预报检验,检验结果证明上述方程具有一定的预报能力。     

EOS/MODIS卫星遥感监测四川省森林火灾的阈值设置研究

本文以2004年4～6月四川省农业气象中心EOS/MODIS资料为基础,参照四川省护林防火办公室的地面森林火灾观测资料,在充分研究EOS/MODIS传感器性能的基础上,通过多次试验研究,根据四川林区的气候特点,设置合理的川西山区森林火灾遥感监测参数,提高了森林火灾遥感监测的准确性.     

EOS/MODIS卫星数据接收处理系统通过验收

１月３０日上午，一种被称之为“EOS／MODIS”卫星数据接收处理系统在自治区气象局建成并通过验收，这在全国气象部门是第一家。新疆乌鲁木齐EOS／MODIS卫星数据接收处理系统验收委员会由中国气象局网络司司长喻纪新任主任委员，自治区气象局局长徐羹慧、中国气象局计财司副司长于新文任副主任委员和国家气象卫星中心、新疆气象局等领导和专家共１５人组成。验收委员会经实地查看、听取工作报告和测试报告，并对有关问题进行了认真讨论和质疑，根据有关合同中要求的技术条款和功能规格需求进行了现场验收，一致认为这套系统是国内具…     

EOS—MODIS卫星资料在北疆大雾监测中的应用分析

根据雾与云、积雪、裸地等地表物在可见光、长波红外和中红外波段的反射及辐射特性差异,利用MODIS卫星多通道多光谱探测数据,采用最佳波段组合法和量化判识指标法,对2006年3月8日到10日北疆大雾天气进行判识检验试验和动态监测分析。结果:发现较利于雾与背景(地物、云、雪)分离的最佳波段是可见光B0.65μm和近红外B0.85μm、短红外B1.64μm、中红外B3.7μm、热红外B11μm,综合判识就可以将云、雾、雪、裸地有效的区分;雾在夜间的有效温度在中红外波段比热红外波段低,可采用中红外和热红外波段的组合方法,根据两通道的亮温差进行雾的监测。     

定量计算渤海海冰参数的遥感方法

利用NOAA及FY-1卫星监测渤海海冰的亮度温度、反照率及其与海水的差异建立了冰、水识别判据,并根据海冰反照率与冰厚的关系,对海冰进行分类。在解决了混合象元内含冰信息提取的基础上,计算了海冰覆盖度和面积等参数。     

GMS实时资料遥感海冰的研究

利用１９９５年１，２月ＧＭＳ－４的红外亮温和可见光反照率资料，以辽东湾海冰为对象，根据冰水物理特性的差异，建立了冰水识别的判据和冰厚与亮温、反照率的对应关系，反演出冰厚和冰密集度数字分布。结果表明，冰水识别的准确率为８４．８％，冰厚反演误差为３．８ｃｍ，密集度反演误差为２２％。     

STUDY ON SEA ICE WITH GMS REAL-TIME DATA

By use of GMS-4 infrared brightness temperature and visible albedo data from January toFebruary in 1995,the method for extracting of sea ice parameters is developed.The digital remotesensing picture is obtained on Liaodong Bay.Based on the difference in physical properties betweenice and water,a criterion distinguishing ice from water is set up.Ice thickness has been calculatedaccording to the relationship between ice thickness and brightness as well as albedo.Iceconcentration is retrieved due to the difference on albedo between ice and water.The resultsindicate that the accuracy of ice-water distinguishing is 84.8%,the errors of ice thickness and iceconcentration are 3.8 cm and 22%,respectively.     

DETECTION OF DAYTIME FOG IN SOUTH CHINA SEA USING MODIS DATA

Based on a current fog detection theory, a multiband threshold method for MODIS data was put forward to detect daytime fog in the South China Sea. It used Bands 1, 2, 18, 20 and 31 of MODIS data to separate fog from the cloud and the sea surface. The digital detection indexes were as follows. If RB1<20%, RB2<20% and RB1>RB2, the pixel was identified to be the sea surface. If RB1>55%, RB2>55% and TB31<273 K, the pixel was identified to be a middle- and high-level cloud. If IFC>20, the pixel was classified to be sea fog. The method was verified with sea fog data observed from the coastal region of Guangdong during January-April 2011. Out of the 13 samples of satellite detection, nine were consistent with the surface observations, three were identified to be low-level the cloud according to the satellite detection but fog according to the surface observations, and only one sample was identified to be the ocean surface by the satellite detection but fog by the surface observations. Because the MODIS data cannot penetrate the cloud or fog, the model was designed for a single field of view which had only one layer of cloud or fog. It can accurately distinguish fog which is not covered by the cloud, but it identifies fog as cloud if the former is covered by a cloud. Generally speaking, the model is effective and feasible.     

海冰在大气环流模式中的重要作用

文章简要综述了次网格尺度海冰非均匀性对大气环流模式性能的影响；南极冰在全球环流和短期气候变化中的作用；以及模式中不同的海冰反照率参数化对地表温度和辐射的影响等研究结果．说明海冰对极地海洋和大气的能量收支及短期气候变化有重要作用，不同的海冰参数化方案对气候模拟结果有重要影响．     

NUMERICAL SIMULATIONS ON INFLUENCES OF VARIATION OF SEA ICE THICKNESS AND EXTENT ON ATMOSPHERIC CIRCULATION

By using a 2-layer AGCM designed by Institute of Atmospheric Physics,Chinese Academy ofSciences.this paper investigates influences of thickness and extent variations in Arctic sea ice onthe atmosphere circulation,particularly on climate variations in East Asia.The simulation resuhshave indicated that sea ice thickness variation in the Arctic exhibits significant influences onsimulation results,particularly on East Asian monsoon.A nearly reasonable distribution of sea icethickness in the model leads directly to stronger winter and summer monsoon over East Asia.andimproves the model's simulation results for Siberia high and Icelandic low in winter.On the otherhand,sea ice thickness variation can excite a teleconnection wave train across Asian Continent,andin low latitudes,the wave propagates from the western Pacific across the equator to the easternPacific.In addition,the variation of sea ice thickness also influences summer convective activitiesover the low latitudes including South China Sea and around the Philippines.Effects of winter sea ice extents in the Barents Sea on atmospheric circulation in the followingspring and summer are also significant.The simulation result shows that when winter sea iceextent in the target region is larger (smaller) than normal.(1)in the following spring (averagedfrom April to June).positive (negative) SLP anomalies occupy the northern central Pacific.whichleads directly to weakened (deepened)Aleutian low.and further favors the light (heavy) sea icecondition in the Bering Sea:(2)in the following summer,thermal depression in Asian Continent isdeepened (weakened).and the subtropical high in the northwestern Pacific shifts northward(southward) from its normal position and to be strengthened (weakened).     

STUDY ON SEA ICE WITH GMS REAL-TIME DATA*

By use of GMS-4 infrared brightness temperature and visible albedo data from January to February in 1995,the method for extracting of sea ice parameters is developed.The digital remote sensing picture is obtained on Liaodong Bay.Based on the difference in physical properties between ice and water,a criterion distinguishing ice from water is set up.Ice thickness has been calculated according to the relationship between ice thickness and brightness as well as albedo.Ice concentration is retrieved due to the difference on albedo between ice and water.The results indicate that the accuracy of ice-water distinguishing is 84.8%,the errors of ice thickness and ice concentration are 3.8 cm and 22%,respectively.     

基于MODIS数据的台湾海峡SST区域遥感监测模型研究

采用SeaDAS模型开展基于MODIS数据的台湾海峡海洋表面温度SST遥感监测时,发现SeaDAS模型在台湾海峡中部SST的监测精度能够满足要求,但在台湾海峡近岸SST的监测误差明显偏大。为此根据2003—2006年台湾海峡近岸观测站点和台湾海峡中部浮标的实测SST数据,采用线性多通道算法建立台湾海峡SST区域遥感监测统计模型,并选择2007年30个SST数据样本对区域统计模型的监测效果进行验证分析。结果表明：在台湾海峡海域采用SeaDAS模型监测SST绝对误差的平均值是1.2 ℃,标准差是0.69 ℃,而采用区域统计模型监测SST绝对误差的平均值下降到0.89 ℃,标准差下降到0.52 ℃,区域统计模型优于SeaDAS模型。     

NUMERICAL SIMULATIONS ON INFLUENCES OF VARIATION OF SEA ICE THICKNESS AND EXTENT ON ATMOSPHERIC CIRCULATION*

By using a 2-layer AGCM designed by Institute of Atmospheric Physics,Chinese Academy of Sciences.this paper investigates influences of thickness and extent variations in Arctic sea ice on the atmosphere circulation,particularly on climate variations in East Asia.The simulation results have indicated that sea ice thickness variation in the Arctic exhibits significant influences on simulation results,particularly on East Asian monsoon.A nearly reasonable distribution of sea ice thickness in the model leads directly to stronger winter and summer monsoon over East Asia.and improves the model's simulation results for Siberia high and Icelandic low in winter.On the other hand,sea ice thickness variation can excite a teleconnection wave train across Asian Continent,and in low latitudes,the wave propagates from the western Pacific across the equator to the eastern Pacific.In addition,the variation of sea ice thickness also influences summer convective activitiesover the low latitudes including South China Sea and around the Philippines.Effects of winter sea ice extents in the Barents Sea on atmospheric circulation in the following spring and summer are also significant.The simulation result shows that when winter sea ice extent in the target region is larger (smaller) than normal.(1)in the following spring (averaged from April to June).positive (negative) SLP anomalies occupy the northern central Pacific.which leads directly to weakened (deepened)Aleutian low.and further favors the light (heavy) sea ice condition in the Bering Sea:(2)in the following summer,thermal depression in Asian Continent is deepened (weakened).and the subtropical high in the northwestern Pacific shifts northward(southward) from its normal position and to be strengthened (weakened).     

南北极海冰的时空变化特征

本文分析了南北极海冰多年平均覆盖资料，给出南北极海冰的年内变化特征，极地海冰最多最少月份的空间分布。计算了２月及９月海冰年际变化方差分布，并对２月及９月南北极海冰７个分区域覆盖面积作了ＥＯＦ分解，为进行南北极海冰影响全球气候的数值试验提供了海冰变化的空间配置