气候变化对大兴安岭北部沼泽景观格局的影响

大兴安岭北部地区由于在高纬、高海拔双重因素作用下,形成了独特的山地沼泽类型。首先使用Logistic回归模型分析了沼泽湿地与18种环境因子(11种地形因子和7种气候因子)的关系,结合CGCM3未来气候模型(加拿大气候模拟和分析中心推出的第三代全球气候耦合模型)预测未来分布,然后利用Fragstats软件计算景观格局的变化。所建模型具有很高的预测精度(ROC为0.96),预测结果表明:到2100年,SRESB1情景下,大兴安岭北部沼泽的潜在分布面积减少54.16%,南部相对平坦的丘陵和山间平原的沼泽大量消失;SRESA1B情景下,面积减少59.62%,南部林区的沼泽几乎全部消失;SRESA2情景下,面积减少73.51%,沼泽几乎完全退化到北部海拔较高处。另外,沼泽景观格局随气候变暖,平均斑块面积变小,形状指数减小,聚集度减少但幅度不大,这说明沼泽分布趋于破碎化,斑块的形状趋向于简单化,沼泽分布由边缘向中心收缩。

东北落叶松属植物潜在分布对气候变化的响应

为探索气候变化对东北落叶松属植物的影响,采用logistic回归模型方法与地理信息系统,预测东北落叶松属植物目前以及未来潜在分布范围。结果表明:兴安落叶松在2050年将向北退200km,在2100年进一步向北退缩300km;长白落叶松在2050年向西北推进约200km,2100年继续推进约200 km;华北落叶松在2050年向东北方向推进280 km;2100年继续推进470 km左右。气候变化极大地改变了三种落叶松的适宜分布区。在未来气候条件下,长白落叶松和华北落叶松将可能替代目前占主导地位的兴安落叶松。

丹江口水库未来径流变化趋势预测研究

应用统计降尺度法将全球气候模式和两参数月水量平衡模型进行耦合,研究未来A2气候情景下丹江口水库径流变化趋势。首先应用统计降尺度法在CGCM2和HadCM3模式下分别预测未来汉江流域上游的月降水和气温情况,然后将它们输入两参数月水量平衡模型,模拟预测丹江口水库的月径流过程。结果表明,在CGCM2气候模式下,丹江口水库径流在2020s和2050s时段比近期减少,2080s时段比近期增加;在HadCM3气候模式下,丹江口水库径流在未来三个时段均比近期增加。

利用海气耦合模式预测的大尺度环流进行热带气旋年频数的预测试验

基于对热带气旋生成频数和大尺度环流相关关系的分析,利用SINTEX-F海气耦合模式预测的大尺度大气环流信息,通过提取模式预测较好与热带气旋生成密切相关的有用信息,建立了一个基于动力模式预测结果的南海和西太平洋热带气旋年频数预测模型,并对1982—2010年的热带气旋生成频数进行预测试验与检验。SINTEX-F海气耦合模式能够较好预测部分与热带气旋生成密切相关的大尺度环流特征,其中包括热带气旋活动区域的海平面气压、对流层风垂直切变、850 hPa热带辐合带和850 hPa 90°E附近的越赤道气流。利用这些大尺度环流建立的预测因子与热带气旋生成频数有很好的相关关系,利用这些预测因子建立的多元回归预测模型对热带气旋频数的拟合率为0.8(相关系数,超过99.9%的信度检验)。预测模型的交叉检验结果表明模型整体预测效果较好。交叉检验预测结果与实况热带气旋频数的相关为0.71(超过了99.9%的信度检验),距平同号率为82.8%。但模型对热带气旋异常年的预测误差较大。

CLIMATE PREDICTION EXPERIMENT FOR TROPICAL CYCLONE GENESIS FREQUENCY USING THE LARGE-SCALE CIRCULATION FORECAST BY A COUPLED GLOBAL CIRCULATION MODEL

Based on an analysis of the relationship between the tropical cyclone genesis frequency and large-scale circulation anomaly in NCEP reanalysis, large-scale atmosphere circulation information forecast by the JAMSTEC SINTEX-F coupled model is used to build a statistical model to predict the cyclogenesis frequency over the South China Sea and the western North Pacific. The SINTEX-F coupled model has relatively good prediction skill for some circulation features associated with the cyclogenesis frequency including sea level pressure, wind vertical shear, Intertropical Convergence Zone and cross-equatorial air flows. Predictors derived from these large-scale circulations have good relationships with the cyclogenesis frequency over the South China Sea and the western North Pacific. A multivariate linear regression(MLR) model is further designed using these predictors. This model shows good prediction skill with the anomaly correlation coefficient reaching, based on the cross validation, 0.71 between the observed and predicted cyclogenesis frequency. However, it also shows relatively large prediction errors in extreme tropical cyclone years(1994 and 1998, for example).

Predictions of ENSO with a Coupled Atmosphere-Ocean General Circulation Model

Predictions of ENSO are described by using a coupled atmosphere-ocean general circulation model. The initial conditions are created by forcing the coupled system using SST anomalies in the tropical Pacific at the background of the coupled model climatology. A series of 24-month hindcasts for the period from November 1981 to December 1997 are carried out to validate the performance of the coupled system. Correlations of SST anomalies in the Nino3 region exceed 0.54 up to 15 months in advance and the rms errors are less than 0.9℃. The system is more skillful in predicting SST anomalies in the 1980s and less in the 1990s. The model skills are also seasonal-dependent, which are lower for the predictions starting from late autumn to winter and higher for those from spring to autumn in a year-time forecast length. The prediction, beginning from March, persists & months long with the correlation skill exceeding 0.6, which is important in predictions of summer rainfall in China. The predictions are succesful in many aspects for the 1997-2000 ENSO events.

Historical and Future Climatic Change Scenarios for Temperature and Rainfall for Iraq

The world is facing a big challenge of climatic change, mainly due to increasing concentrations of GHGs （greenhouse gases） in the atmosphere. Many researches indicated that the climate change occurred disproportionately on developing countries such as MENA （Middle East and North Africa） countries. The climatic model CGCM3.1 （T47） 2 is used in this research to explain the changes in average temperatures and the rainfall on the MENA region with special emphases on Iraq. Historical records （1900-2009） and future （2020-2099） were studied and compared; each period was divided to four sub-periods of thirty years. The results showed that the average monthly temperature for the four historical periods fluctuated between the lowest and highest value as follows： 9.2-32.9, 10.3-32.7, 9.3-32.8 and 8.6-33.9 （℃）. The rainfall for historical periods kept on the same distribution during the past 109 years, and fluctuated between the lowest and highest value of 21.3 mm and 37.6 mm with an average that reached up to 26.51 mm. For the future period, the maximum average monthly temperature reached up to 37.41 （℃） during June and minimum average monthly temperature reached up to 4.24 （℃） during January. The average monthly temperature fluctuated giving a clear impression that the future portends a higher temperature. The average monthly rainfall, for the future period, fluctuated between the lowest and highest value of 12.91 mm and 20.63 mm with an average that reached 16.84 mm which represent a reduction percentage of about 36.47% relative to the historical record of rainfall for the sanae months.

基于CGCM就业创业理念的物流管理专业培养体系重构研究

就业创业理念的专业培养体系是教学实施的关键环节,其效果如何直接关系到物流人才培养的质量。文中结合合肥财经职业学院开展的“就业创业”理念的专业培养体系重构,从培育就业创业能力、引导就业创业意识、创造就业创业环境、树造就业创业团队等四个方面探讨物流管理专业培养体系的新思路和新做法。

ENSO Variability Simulated by a Coupled General Circulation Model:ECHAM5/MPI-OM

The accurate simulation of the equatorial sea surlhce temperature （SST） variability is crucial for a proper representation or prediction of the El Nino-Southern Os- cillation （ENSO）. This paper describes the tropical variability simulated by the Max Planck Institute （MPI） forr meteorology coupled atmosphere-ocean general circulation model （CGCM）. A control simulation with pre-industrial greenhouse gases is analyzed, and the simulation of key oceanic features, such as SST, is compared with observa- tions. Results from the 400-yr control simulation show that the model＇s ENSO variability is quite realistic in terms of structure, strength, and period. Also, two related features （the annual cycle of SST and the-phase locking of ENSO events）, which are significant in determining the model＇s performance of realistic ENSO prediction, are further validated to be well reproduced by the MPI cli mate model, which is an atmospheric model ECHAM5 （which fuses the EC tbr European Center and HAM for Hamburg） coupled to an MPI ocean model （MPI-OM）, ECHAMS/MPI-OM.

Assessment of Climate Change for Precipitation and Temperature Using Statistical Downscaling Methods in Upper Godavari River Basin, India

In the present study SDSM downscaling model was used as a tool for downscaling weather data statistically in upper Godavari river basin. Two Global Climate Models (GCMs), CGCM3 and HadCM3, have been used to project future maximum temperature (Tmax), minimum temperature (Tmin) and precipitation. The predictor variables are extracted from: 1) the National Centre for Environmental Prediction (NCEP) reanalysis dataset for the period 1961-2003, 2) the simulations from the third-generation Hadlycentre Coupled Climate Model (HadCM3) and Coupled Global Climate Model (CGCM3) variability and changes in Tmax, Tmin and precipitation under scenarios A1B and A2 of CGCM3 model and A2 and B2 of HadCM3 model have been presented for future periods: 2020s, 2050s and 2080s. The scatter-plots and cross-correlations are used for verifying the reliability of the simulation. Maximum temperature increases in future for almost all the scenarios for both GCMs. Also downscaled future precipitation shows increasing trends for all scenarios.

东亚冬季风-暖池状况-ENSO循环的关系

基于观测资料的分析和海－气耦合模式（ＣＧＣＭ）的数值模拟结果，提出关于ＥＮＳＯ发生机制的一个新观点：持续的强（弱）东亚冬季风将导致赤道西太平洋地区持续的西（东）风异常；而异常的赤道西（东）风可使得已在暖池区存在相当长一段时间的正（负）次表层海温距平（ＳＯＴＡ）向东传播；沿温跃层东传的正（负）ＳＯＴＡ将造成赤道东太平洋正（负）海表温度距平（ＳＳＴＡ）的出现和 Ｅ１ Ｎｉｎｏ（ＬａＮｉｎａ）事件的发生．当 ＥＮＳＯ发生之后， Ｅ１ Ｎｉｎｏ（Ｌａ Ｎｉｎａ）事件的影响又将削弱（加强）东亚冬季风的活动．

The correctness to the spuriously simulated semi-annual cycle of the sea surface temperature in the equatorial eastern Pacific

One of the challenges faced by the climate model of the Community Climate System Model version 3 (CCSM3) is the spuriously simulated semi-annual cycle of the sea surface temperature (SST) in the equatorial eastern Pacific. This model bias has limited the performance of the climate simulation and prediction. Based on the surface wave-circulation coupled theory, an atmosphere-wave-ocean coupled model was developed, which incorporates the MASNUM (key laboratory of Marine Sciences and Numerical Modeling) wave number spectral model into CCSM3. The new coupled atmosphere-wave-ocean model successfully removes the spurious semi-annual cycle simulated by the original CCSM3 and reasonably produces an SST annual cycle with warm and cold phases in April and August, respectively. The correlation between the simulated and observed SST in the equatorial eastern Pacific is improved from 0.66 to 0.93. The ocean surface layer heat budget analysis indicates that the wave-induced vertical mixing is responsible for improving the simulation of the SST seasonal cycle in the equatorial eastern Pacific.

An Assessment of ENSO Stability in CAMS Climate System Model Simulations

We present an overview of the El Ni?o–Southern Oscillation(ENSO) stability simulation using the Chinese Academy of Meteorological Sciences climate system model(CAMS-CSM). The ENSO stability was quantified based on the Bjerknes(BJ) stability index. Generally speaking, CAMS-CSM has the capacity of reasonably representing the BJ index and ENSO-related air–sea feedback processes. The major simulation biases exist in the underestimated thermodynamic damping and thermocline feedbacks. Further diagnostic analysis reveals that the underestimated thermodynamic feedback is due to the underestimation of the shortwave radiation feedback, which arises from the cold bias in mean sea surface temperature(SST) over central–eastern equatorial Pacific(CEEP). The underestimated thermocline feedback is attributed to the weakened mean upwelling and weakened wind–SST feedback(μ_a) in the model simulation compared to observation. We found that the weakened μ_a is also due to the cold mean SST over the CEEP.The study highlights the essential role of reasonably representing the climatological mean state in ENSO simulations.

Development of a Downscaling Method in China Regional Summer Precipitation Prediction

A downscaling method taking into account of precipitation regionalization is developed and used in the regional summer precipitation prediction （RSPP） in China. The downscaling is realized by utilizing the optimal subset regression based on the hindcast data of the Coupled Ocean-Atmosphere General Climate Model of National Climate Center （CGCM/NCC）, the historical reanalysis data, and the observations. The data are detrended in order to remove the influence of the interannual variations on the selection of predictors for the RSPP. Optimal predictors are selected through calculation of anomaly correlation coefficients （ACCs） twice to ensure that the high-skill areas of the CGCM/NCC are also those of observations, with the ACC value reaching the 0.05 significant level. One-year out cross-validation and independent sample tests indicate that the downscaling method is applicable in the prediction of summer precipitation anomaly across most of China/vith high and stable accuracy, and is much better than the direct CGCM/NCC prediction. The predictors used in the downscaling method for the RSPP are independent and have strong physical meanings, thus leading to the improvements in the prediction of regional precipitation anomalies.

EVALUATION OF CGCM AND SIMULATION OF REGIONAL CLIMATE CHANGE IN EAST ASIA

In this paper,experiment results about East Asia climate from five CGCMs are described.The ability of the models to simulate present climate and the simulated response to increased carbon dioxide are both covered.The results indicate that all models show substantial changes in climate when carbon dioxide concentrations are doubled.In particular,the strong surface warming at high latitudes in winter and the significant increase of summer precipitation in the monsoon area are produced by all models.Regional evaluation results show that these five CGCMs are particularly good in simulating spatial distribution of present climate.The main characteristics of the seasonal mean H500,SAT, MSLP field can be simulated by most CGCMs.But there are significant systematic errors in SAT, MSLP,HS00 fields in most models.On the whole,DKRZ OPYC is the best in simulating the present climate in East Asia.

RESPONSES OF A GLOBAL CGCM TO CO_2 INCREASE

The responses of the climate system to increase of atmospheric carbon dioxide(CO_2)are studied by using a new version of the Bureau of Meteorological Research Centre(BMRC)global coupled general circulation model(CGCM).Two simulations are run:one with atmospheric CO_2 concentration held constant at 330 ppm,the other with a tripling of atmospheric CO_2(990 ppm). Results from the 41-year control coupled integration are applied to analyze the mean state, seasonal cycle and interannual variability in the model.Comparisons between the greenhouse experiment and the control experiment then provide estimations of the influence of increased CO_2 on climate changes and climate variability.Especially discussed is the question on whether the climate changes concerned with CO_2 inerease will impact interannual variability in tropical Pacific, such as ENSO.

Characteristics and Numerical Simulation of the Tropical Intraseasonal Oscillations under Global Warming

Using the ECMWF reanalysis daily 200-hPa wind data during the two 20-yr periods from 1958 to 1977 and from 1980 to 1999, the characteristics and changes of Intraseasonal Oscillations （ISO） in the two periods associated with global warming are analyzed and compared in this study. It is found that during the last 20 years, the ISO has weakened in the central equatorial Pacific Ocean, but becomes more active in the central Indian Ocean and the Bay of Bengal; under the background of the global warming, increase in the amplitude of ISO intensity suggests that the ISO has become more active than before, with an obvious seasonal cycle, i.e., strong during winter and spring, but weak during summer and autumn; the energy of the upper tropospheric zonal winds has more concentrated in wave numbers 1-3, and the frequency of ISO tended to increase. Comparison between the results of control experiment and CO2 increase （1% per year） experiment of FGOALS-1.0g （developed at LASG） with the first and second 20-yr observations, is also performed, respectively. The comparative results show that the spatial structure of the ISO was well reproduced, but the strength of ISO was underestimated. On the basis of space-time spectral analysis, it is found that the simulated ISO contains too much high frequency waves, leading to the underestiniation of ISO intensity due to the dispersion of ISO energy. However, FGOALS-1.0g captured the salient features of ISO under the global warming background by two contrast experiments, such as the vitality and frequency-increasing of ISO in the central Indian Ocean and the Bay of Bengal.