Future impact of anthropogenic sulfate aerosol on North Atlantic climate     

Irene Fischer-Bruns  Dorothea F. Banse  Johann Feichter 《Climate Dynamics》2009,32(4):511-524

We examine the simulated future change of the North Atlantic winter climate influenced by anthropogenic greenhouses gases and sulfate aerosol. Two simulations performed with the climate model ECHAM4/OPYC3 are investigated: a simulation forced by greenhouse gases and a simulation forced by greenhouse gases and sulfate aerosol. Only the direct aerosol effect on the clear-sky radiative fluxes is considered. The sulfate aerosol has a significant impact on temperature, radiative quantities, precipitation and atmospheric dynamics. Generally, we find a similar, but weaker future climate response if sulfate aerosol is considered additionally. Due to the induced negative top-of-the-atmosphere radiative forcing, the future warming is attenuated. We find no significant future trends in North Atlantic Oscillation (NAO) index in both simulations. However, the aerosol seems to have a balancing effect on the occurence of extreme NAO events. The simulated correlation patterns of the NAO index with temperature and precipitation, respectively, agree well with observations up to the present. The extent of the regions influenced by the NAO tends to be reduced under strong greenhouse gas forcing. If sulfate is included and the warming is smaller, this tendency is reversed. Also, the future decrease in baroclinicity is smaller due to the aerosols’ cooling effect and the poleward shift in track density is partly offset. Our findings imply that in simulations where aerosol cooling is neglected, the magnitude of the future warming over the North Atlantic region is overestimated, and correlation patterns differ from those based on the future simulation including aerosols.  相似文献   

温室气体浓度增加情景下西北太平洋热带气旋变化的模拟分析   总被引：3，自引：1，他引：2  

黄勇  李崇银 《气候与环境研究》2010,15(1):1-10

利用德国Max-Planck气象研究所参与政府间气候变化委员会(The Intergovernmental Panelon Cli-mate Change,IPCC)第四次评估报告的气候系统模式(ECHAM5/MPI-OM)的数值模拟结果,分析研究了全球增暖背景下西北太平洋热带气旋的变化。结果表明,ECHAM5模式较好的模拟出了热带气旋的基本结构和频数的分布特征。当大气中CO2浓度增加时,热带气旋中心的最低气压升高,850hPa正涡度降低,风速减小,风场出现反气旋性环流异常,暖心强度减弱,气旋的低层径向流入和高层径向流出减少,气旋总体强度减弱。CO2浓度的增加会总体上减少西北太平洋热带气旋的生成频数,从模拟结果看年均减少10个左右。就CO2浓度增加对热带气旋频数季节变化的影响而言,CO2浓度增加所引起气旋频数减少较平均的分配到多个月份里,表明CO2浓度增加引起的大气环流异常在全年都会对西北太平洋热带气旋的发生频数产生影响。分析加拿大参加IPCC第四次评估报告的CGCM3.1(T47)模拟资料,其结果与ECHAM5资料得到的结果大致相似。  相似文献   

DEVELOPING AND NON-DEVELOPING TROPICAL CYCLONES AS REVEALED BY HIGH DENSITY CLOUD MOTION WINDS   总被引：1，自引：0，他引：1  

方翔  许健民  张其松 《热带气象学报(英文版)》2001,7(1):80-85

An algorithm for computation of cloud motion winds has been developed at the National Satellite Meteorological Center in China. Since 1997, it has been applied to calculate the cloud motion winds for a 1.25 lat. 1.25 long. mesh over the northwest Pacific region with the satellite data from GMS-5. The development of the tropical cyclones is studied. It shows that the tropical cyclone is usually intrigued by the westerly jet streams at the upper levels of the troposphere, which may be caused by mid-latitude troughs well extending into the tropics. During the prime season of summer, the westerly flowing equatorward of the TUTT may also be a cause for the generation of typhoons.  相似文献   

ANALYSIS OF EXTRATROPICAL TRANSITION OF TROPICAL CYCLONE OVER MAINLAND CHINA   总被引：1，自引：1，他引：0  

朱佩君  郑永光  陶祖钰 《热带气象学报(英文版)》2003,9(2):152-157

~~ANALYSIS OF EXTRATROPICAL TRANSITION OF TROPICAL CYCLONE OVER MAINLAND CHINA@朱佩君$Key Laboratory of Severe Storm Research, Department of Atmospheric Sciences, Physics School, Peking University, Beijing 100871 China @郑永光$Key Laboratory of Severe Storm Research, Department of Atmospheric Sciences, Physics School, Peking University, Beijing 100871 China @陶祖钰$Key Laboratory of Severe Storm Research, Department of Atmospheric Sciences, Physi…  相似文献   

双热带气旋相互作用的研究   总被引：7，自引：1，他引：6  

田永祥  寿绍文 《气象学报》1998,56(5):584-593

采用无基本气流的无辐散正压模式模拟了双热带气旋的运动。应用非对称理论研究了双热带气旋的相互作用。双热带气旋中的每个热带气旋主要由通过其中心的非对称气流（即通风气流）作用而移动。这股非对称气流是由其自身的线性和非线性效应产生的非对称涡旋与其配对热带气旋形成的非对称涡旋相叠加而引起的。  相似文献   

On the Forcing of the Radial-vertical Circulation within Cyclones-Part 1: Concepts and Equations     

D. R. Johnson  Zhuojian Yuan 《大气科学进展》1998,15(3):346-369

ＯｎｔｈｅＦｏｒｃｉｎｇｏｆｔｈｅＲａｄｉａｌ－ｖｅｒｔｉｃａｌＣｉｒｃｕｌａｔｉｏｎｗｉｔｈｉｎＣｙｃｌｏｎｅｓ—Ｐａｒｔ１：ＣｏｎｃｅｐｔｓａｎｄＥｑｕａｔｉｏｎｓＤ．Ｒ．ＪｏｈｎｓｏｎａｎｄＺｈｕｏｊｉａｎＹｕａｎＳｐａｃｅＳｃｉｅｎｃｅａｎｄ...  相似文献   

非绝热加热对中高纬大气低频振荡的调频作用   总被引：6，自引：2，他引：4  

陆维松  马淑杰 《南京气象学院学报》1998,21(3):336-345

用诊断方法和数值试验两种方法,研究了非绝热加热对中高纬大气低频振荡的调频作用,首先应用１９７９～１９８９年欧洲中心资料进行功率谱分析,得到：（１）夏季与冬季相比,波动的主周期有有缩短的趋势,（２）ＥｌＮｉｎｏ事件和ＬａＮｉｎａ事件期间,冬夏两季的波动主要周期分别有缩短和变长的趋势,然后,应用强迫耗散准地转正压涡度方程的全球谱模式,考虑三个行星波准共振,积分９０ｄ,得到：（１）三个行星波之间存在的很  相似文献   

NUMERICAL STUDY ON THE EFFECTS OF SEA SURFACE TEMPERATURE ON TROPICAL CYCLONE INTENSITY-PART I:NUMERICAL EXPERIMENT OF THE TROPICAL CYCLONE INTENSITY RELATED TO SST ^*     

Duan Yihong  Qin Zenghao  Gu dianfeng  Li Yongping 《Acta Meteorologica Sinica》1998,12(2):142-148

In the context of a model of tropical cyclone intensity based on an improved meso-scale atmospheric model, numerical simulation is performed of the track and intensity variation of tropical cyclones(TC) arising from sea surface temperature(SST) variation over a specified sea region. Evidence suggests that the model is capable of modeling quite welt the track and intensity of TC:SST variation leads to an abrupt change in the cyclone intensity:the response of the cyclone to the abrupt SST change lasts 8-12 h.  相似文献   

The Role of Mid-Latitude Pacific Cyclones in the Winter Precipitation of California*     

Marilyn Raphael  Gerald Mills 《The Professional geographer》1996,48(3):251-262

The characteristics of the mid-latitude Pacific cyclones that produce precipitation over California are investigated statistically to determine their role in governing precipitation receipt. From all cyclones occurring over the Pacific Ocean from December through March and between 1965–1990 inclusive, we identify a subset of cyclones likely to produce precipitation over California. The characteristics analyzed are track, frequency, duration, speed, central pressure, and proximity. These are related to monthly precipitation for the entire period and are also used to explain the difference in precipitation received during the earlier (wet) and latter (dry) halves of the 1980s. Results indicate that the winter cyclones responsible for precipitation over California originate in the southeast quadrant of the region influenced by the Aleutian Low and decay south of the Gulf of Alaska. The extent of cyclonic activity over the east Pacific Ocean near California diminished during the dry period. There were fewer cyclones, they were significantly weaker, and they traveled along a more meridional track during the dry period.  相似文献   

ON THE PREDICTION OF TROPICAL CYCLONE LANDFALL AND INFLUENCE ON SOUTHERN CHINA USING MONTHLY OLR ANOMALIES FOR PRIME SUMMER   总被引：1，自引：1，他引：1  

段丽  蒋尚城 《热带气象学报(英文版)》2002,8(2):201-206

With the OLR data,the landfall and activity of tropical cyclones(TC) in southern China over a 20-year period(1975～1994) are studied.The result shows that the variation of the monthly anomalous OLR is somewhat teleconnected with the TC activity in southern China.The former is used to predict short-term climate for the latter over months with frequent or no TC influence.To some externt,the relationship between the TC activity in southern China and the monthly mean OLR anomalies is dependent on the climatological location of the subtropical high in northwestern Pacific region.  相似文献