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1.
应用NCEP地面热通量资料, 研究了青藏高原地面感热、潜热的气候状况及其与初夏东亚大气环流之间的关系。发现高原地面热通量的异常将影响高原地区上空的垂直运动与辐散辐合运动, 从而引起东亚地区高度场及风场的异常。同时, 青藏高原地区地面热通量与后期东亚地区的环流变化也有密切关系, 这种关系可为预测东亚地区初夏环流异常提供有意义的指标。  相似文献   

2.
北太平洋海气界面湍流热通量的年际变化   总被引:4,自引:1,他引:3  
郑建秋  任保华  李根 《大气科学》2009,33(5):1111-1121
本文采用美国伍兹霍尔海洋研究所客观分析海气通量项目提供的1958~2006年月平均的湍流热通量及相关气象场数据, 利用EOF分析、小扰动方法、线性回归、相关分析等方法研究了北太平洋海气界面湍流热通量年际变化的时空特征、 影响因子及其与大气环流的关系。结果表明, 北太平洋湍流热通量的年际变化在冬季最为显著。我国东部海域及其向中东太平洋的延伸部分为冬季潜热通量和感热通量年际变化的关键区。冬季潜热通量的年际变化在副热带太平洋和菲律宾海域主要受风速变化影响, 在北太平洋的高纬和低纬海域尤其是赤道中太平洋主要受比湿差变化影响, 而冬季感热通量的年际变化在整个北太平洋都主要受海气温差变化影响。受大尺度环流影响, 异常低压中心的东 (西) 侧海气比湿差和海气温度差偏小 (偏大), 所以异常低压中心的东 (西) 侧潜热输送和感热输送偏弱 (偏强)。  相似文献   

3.
利用1979—2017年TropFlux海气热通量资料、ERA5再分析资料及HadISST资料,分析了冬季北大西洋涛动(North Atlantic Oscillation, NAO)与同期热带印度洋海气热通量的关系。结果表明,NAO指数与热带印度洋海气净热通量整体上呈负相关,意味着NAO为正位相时,海洋向大气输送热量,其显著区域主要位于热带西印度洋(50°~70°E,10°S~10°N)。净热通量的变化主要依赖于潜热通量和短波辐射的变化;潜热通量和短波辐射在NAO正(负)位相事件期间的贡献率分别为72.96%和61.48%(71.72%和57.06%)。NAO可通过Rossby波列影响印度洋地区局地大气环流,进而影响海气热通量;当NAO为正位相时,波列沿中低纬路径传播至印度洋地区,在阿拉伯海北部对流层高层触发异常反气旋环流。该异常反气旋性环流加强了阿拉伯高压,使得北印度洋偏北风及越赤道气流加强。伴随风速的加强,海面蒸发增强,同时加强的越赤道气流导致热带辐合带强度偏强,深对流加强引起对流层水汽和云量增多,进而引起海表下行短波辐射减少。  相似文献   

4.
TOGA-COAREIOP海表通量估算   总被引:3,自引:0,他引:3  
姚华栋  李骥  丁一汇 《气象学报》1996,54(6):693-708
使用TOGA-COAREIOP1992年11月5日至1993年2月19日向阳红5号海上船舶(2°S,156°E)观测资料,通过3种不同的总体方法估算了这个点的海表面通量。首先得出一个中性拖曳系数和风速之间的准线性关系,然后用迭代法处理依赖于稳定度的拖曳系数和输送系数,在此基础上计算了动量、感热和潜热通量。在暖池区与西风相对应的通量远大于东信风相对应的通量,海表通量的量值也依赖于稳定度,特别是在弱风条件下。估算的海表净热量平衡表明从海洋向大气大量的热输送主要是由潜热通量和有效长波辐射产生的。其中潜热通量的数值最大、感热通量数值最小。最后和同期日本R/VHakuho考察船(0°,156°E)用涡动相关法得到的直接测量通量比较,作了精确度分析,表明用总体方法估算的通量是可靠的。并用向阳红5号船的资料估算的有效长波辐射和直接测量值作了比较,也和热带西太平洋TOGA调查作了比较分析。  相似文献   

5.
热带西太平洋海面通量与气象要素关系的诊断分析   总被引:4,自引:1,他引:3  
用TOGACOARE加强期在赤道带西太平洋暖池中的观测船MoanaWave和浮标获得的小时风、温、湿、海温资料计算了海面各种通量。分析潜热通量随海面温度SST的变化特征,发现小风期潜热通量LH在某SST处出现最大值,大风时不出现此现象,即LH随SST变化的主要原因是风随SST的变化,其次是气海湿度差Δq及传输系数CE随SST的变化。用相关分析法分析小风期、西风爆发期、对流扰动期等不同时期中各通量与各气象要素的关系发现,潜热通量和动量通量主要决定于风,对感热通量起作用的主要是气海温差,降水也可通过气海温差和风影响感热通量。  相似文献   

6.
农田近地面层CO2和湍流通量特征研究   总被引:11,自引:0,他引:11  
刘树华  麻益民 《气象学报》1997,55(2):187-199
利用1985年5月至6月在北京郊区中国科学院农业生态试验研究站的麦田中实测的小麦不同生长期的CO2浓度梯度、光合有效辐射、净辐射、土壤热通量和温度、湿度及风速梯度等量的数据,采用空气动力学方法,计算了CO2通量、感热通量、潜热通量和动量通量。并对观测场地、仪器设备、校准方法及误差分析进行了描述。结果表明:从5月14日到6月15日,在1m,2m和10m处,CO2浓度振幅的日变化分别为103.4到27.5,87.5到27.3和69.8到11.5ppm;光合型和呼吸型的平均CO2浓度分别为345.3,350.6,357.5ppm和373.9,369.7,362.1ppm。在白天,CO2通量和梯度的输送方向是从大气向植被,在中午(11时到13时)输送达到负的最大值。在夜间,CO2通量和梯度输送的方向与白天相反,并且,在早晨(4时到6时)达到正的最大值。CO2通量与净辐射(Rn)、可利用能(H+LE)、光合有效辐射和动量通量之间有较好的相关关系  相似文献   

7.
基于通量距平的大气-海洋-海冰耦合模式   总被引:2,自引:0,他引:2  
该文是对基于月平均通量距平(MFA)的海气耦合方案及其在4个海气耦合的环流模式中应用情况的一个综合评述.这些模式的实施情况表明,由于采用精细化了的参考通量,修正的MFA(MMFA)比它的原型具有更为稳定的控制气候漂移的能力.  相似文献   

8.
WRF模式对金塔绿洲效应的数值模拟   总被引:4,自引:3,他引:1       下载免费PDF全文
利用美国NCAR中心的天气研究与预报模式WRF,对金塔绿洲的温度场、环流场、能量场的结构及其日变化特征进行了较为细致的模拟研究。结果表明,WRF模式能较好地模拟出非均匀下垫面上绿洲和戈壁的近地面温度、风场、净辐射、感热和潜热等要素的变化特征及日变化规律,较为完整地呈现出绿洲"冷岛效应",模拟的近地面风向和观测值吻合较好。通过对能量场的时空分析,发现下垫面的植被类型、土壤类型和土壤湿度对绿洲白天感热、潜热、土壤热通量和净辐射等有很大影响,绿洲白天净辐射峰值比戈壁大,潜热通量比感热通量大;白天大气向地面传输热量,绿洲地表获得的热通量大;而夜间地表向上传递热量,绿洲释放的热通量比戈壁大。更加细致地研究这些现象对深入了解绿洲气候的形成和维持机理具有重要的意义。  相似文献   

9.
杜钦  高阳华  黄静  高松 《湖北气象》2021,40(2):208-215
基于通量观测、邻近自动气象观测站和ERA5-Land再分析数据,结合重庆西部暴雨个例,讨论了重庆山地通量观测资料的可靠性和适用性,并对通量观测在2019年度的不同时间尺度变化特征进行分析,结果如下:(1)通量站与邻近气象站有相似的气象背景,通量观测相对于ERA5-land再分析资料更能反映出地表感热和潜热通量在降水期间...  相似文献   

10.
TOGA型海-气耦合模式直接模拟的SST误差分析   总被引:1,自引:1,他引:0  
本文对一个TOGA(热带太平洋和全球大气)型耦合环流模式直接耦合30 a(1980—2009年)的模拟结果进行分析,发现模拟的热带太平洋海表温度存在严重的"气候漂移"现象。通过对模式海表温度控制方程中加热和冷却项的分析,特别是对海表热通量和风应力的分析,指出了两者的误差在热带太平洋海表温度的"气候漂移"现象中扮演的角色。为了进一步证实分析的结果,通过4个敏感性试验分析热通量和风应力对热带太平洋海表温度分布的作用,特别是热通量对西太平洋暖池的形成,而风应力对东太平洋冷舌的形成均有重要的作用以及纬向风应力和经向风应力对冷舌形成的相对贡献。  相似文献   

11.
Using the International Comprehensive Ocean-Atmosphere Data Set(ICOADS) and ERA-Interim data, spatial distributions of air-sea temperature difference(ASTD) in the South China Sea(SCS) for the past 35 years are compared,and variations of spatial and temporal distributions of ASTD in this region are addressed using empirical orthogonal function decomposition and wavelet analysis methods. The results indicate that both ICOADS and ERA-Interim data can reflect actual distribution characteristics of ASTD in the SCS, but values of ASTD from the ERA-Interim data are smaller than those of the ICOADS data in the same region. In addition, the ASTD characteristics from the ERA-Interim data are not obvious inshore. A seesaw-type, north-south distribution of ASTD is dominant in the SCS; i.e., a positive peak in the south is associated with a negative peak in the north in November, and a negative peak in the south is accompanied by a positive peak in the north during April and May. Interannual ASTD variations in summer or autumn are decreasing. There is a seesaw-type distribution of ASTD between Beibu Bay and most of the SCS in summer, and the center of large values is in the Nansha Islands area in autumn. The ASTD in the SCS has a strong quasi-3a oscillation period in all seasons, and a quasi-11 a period in winter and spring. The ASTD is positively correlated with the Nio3.4 index in summer and autumn but negatively correlated in spring and winter.  相似文献   

12.
<正>The Taal Volcano in Luzon is one of the most active and dangerous volcanoes of the Philippines. A recent eruption occurred on 12 January 2020(Fig. 1a), and this volcano is still active with the occurrence of volcanic earthquakes. The eruption has become a deep concern worldwide, not only for its damage on local society, but also for potential hazardous consequences on the Earth’s climate and environment.  相似文献   

13.
The moving-window correlation analysis was applied to investigate the relationship between autumn Indian Ocean Dipole (IOD) events and the synchronous autumn precipitation in Huaxi region, based on the daily precipitation, sea surface temperature (SST) and atmospheric circulation data from 1960 to 2012. The correlation curves of IOD and the early modulation of Huaxi region’s autumn precipitation indicated a mutational site appeared in the 1970s. During 1960 to 1979, when the IOD was in positive phase in autumn, the circulations changed from a “W” shape to an ”M” shape at 500 hPa in Asia middle-high latitude region. Cold flux got into the Sichuan province with Northwest flow, the positive anomaly of the water vapor flux transported from Western Pacific to Huaxi region strengthened, caused precipitation increase in east Huaxi region. During 1980 to 1999, when the IOD in autumn was positive phase, the atmospheric circulation presented a “W” shape at 500 hPa, the positive anomaly of the water vapor flux transported from Bay of Bengal to Huaxi region strengthened, caused precipitation ascend in west Huaxi region. In summary, the Indian Ocean changed from cold phase to warm phase since the 1970s, caused the instability of the inter-annual relationship between the IOD and the autumn rainfall in Huaxi region.  相似文献   

14.
The atmospheric and oceanic conditions before the onset of EP El Ni?o and CP El Ni?o in nearly 30 years are compared and analyzed by using 850 hPa wind, 20℃ isotherm depth, sea surface temperature and the Wheeler and Hendon index. The results are as follows: In the western equatorial Pacific, the occurrence of the anomalously strong westerly winds of the EP El Ni?o is earlier than that of the CP El Ni?o. Its intensity is far stronger than that of the CP El Ni?o. Two months before the El Ni?o, the anomaly westerly winds of the EP El Ni?o have extended to the eastern Pacific region, while the westerly wind anomaly of the CP El Ni?o can only extend to the west of the dateline three months before the El Ni?o and later stay there. Unlike the EP El Ni?o, the CP El Ni?o is always associated with easterly wind anomaly in the eastern equatorial Pacific before its onset. The thermocline depth anomaly of the EP El Ni?o can significantly move eastward and deepen. In addition, we also find that the evolution of thermocline is ahead of the development of the sea surface temperature for the EP El Ni?o. The strong MJO activity of the EP El Ni?o in the western and central Pacific is earlier than that of the CP El Ni?o. Measured by the standard deviation of the zonal wind square, the intensity of MJO activity of the EP El Ni?o is significantly greater than that of the CP El Ni?o before the onset of El Ni?o.  相似文献   

15.
Various features of the atmospheric environment affect the number of migratory insects, besides their initial population. However, little is known about the impact of atmospheric low-frequency oscillation(10 to 90 days) on insect migration. A case study was conducted to ascertain the influence of low-frequency atmospheric oscillation on the immigration of brown planthopper, Nilaparvata lugens(Stl), in Hunan and Jiangxi provinces. The results showed the following:(1) The number of immigrating N. lugens from April to June of 2007 through 2016 mainly exhibited a periodic oscillation of 10 to 20 days.(2) The 10-20 d low-frequency number of immigrating N. lugens was significantly correlated with a low-frequency wind field and a geopotential height field at 850 h Pa.(3) During the peak phase of immigration, southwest or south winds served as a driving force and carried N. lugens populations northward, and when in the back of the trough and the front of the ridge, the downward airflow created a favorable condition for N. lugens to land in the study area. In conclusion, the northward migration of N. lugens was influenced by a low-frequency atmospheric circulation based on the analysis of dynamics. This study was the first research connecting atmospheric low-frequency oscillation to insect migration.  相似文献   

16.
基于最新的GTAP8 (Global Trade Analysis Project)数据库,使用投入产出法,分析了2004年到2007年全球贸易变化下南北集团贸易隐含碳变化及对全球碳排放的影响。结果显示,随着发展中国家进出口规模扩张,全球贸易隐含碳流向的重心逐渐向发展中国家转移。2004年到2007年,发达国家高端设备制造业和服务业出口以及发展中国家资源、能源密集型行业及中低端制造业出口的趋势加强,该过程的生产转移导致全球碳排放增长4.15亿t,占研究时段全球贸易隐含碳增量的63%。未来发展中国家的出口隐含碳比重还将进一步提高。贸易变化带来的南北集团隐含碳流动变化对全球应对气候变化行动的影响日益突出,发达国家对此负有重要责任。  相似文献   

17.
The spatial and temporal variations of daily maximum temperature(Tmax), daily minimum temperature(Tmin), daily maximum precipitation(Pmax) and daily maximum wind speed(WSmax) were examined in China using Mann-Kendall test and linear regression method. The results indicated that for China as a whole, Tmax, Tmin and Pmax had significant increasing trends at rates of 0.15℃ per decade, 0.45℃ per decade and 0.58 mm per decade,respectively, while WSmax had decreased significantly at 1.18 m·s~(-1) per decade during 1959—2014. In all regions of China, Tmin increased and WSmax decreased significantly. Spatially, Tmax increased significantly at most of the stations in South China(SC), northwestern North China(NC), northeastern Northeast China(NEC), eastern Northwest China(NWC) and eastern Southwest China(SWC), and the increasing trends were significant in NC, SC, NWC and SWC on the regional average. Tmin increased significantly at most of the stations in China, with notable increase in NEC, northern and southeastern NC and northwestern and eastern NWC. Pmax showed no significant trend at most of the stations in China, and on the regional average it decreased significantly in NC but increased in SC, NWC and the mid-lower Yangtze River valley(YR). WSmax decreased significantly at the vast majority of stations in China, with remarkable decrease in northern NC, northern and central YR, central and southern SC and in parts of central NEC and western NWC. With global climate change and rapidly economic development, China has become more vulnerable to climatic extremes and meteorological disasters, so more strategies of mitigation and/or adaptation of climatic extremes,such as environmentally-friendly and low-cost energy production systems and the enhancement of engineering defense measures are necessary for government and social publics.  相似文献   

18.
正ERRATUM to: Atmospheric and Oceanic Science Letters, 4(2011), 124-130 On page 126 of the printed edition (Issue 2, Volume 4), Fig. 2 was a wrong figure because the contact author made mistake giving the wrong one. The corrected edition has been updated on our website. The editorial office is sincerely sorry for any  相似文献   

19.
20.
Index to Vol.31     
正AN Junling;see LI Ying et al.;(5),1221—1232AN Junling;see QU Yu et al.;(4),787-800AN Junling;see WANG Feng et al.;(6),1331-1342Ania POLOMSKA-HARLICK;see Jieshun ZHU et al.;(4),743-754Baek-Min KIM;see Seong-Joong KIM et al.;(4),863-878BAI Tao;see LI Gang et al.;(1),66-84BAO Qing;see YANG Jing et al.;(5),1147—1156BEI Naifang;  相似文献   

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