聊城地区大暴雨的若干特征

本文对影响我区的十二次大暴雨过程进行了综合分析,找出了产生聊城地区大暴雨的若干特征,试图给预报大暴雨提供一定依据。 一、大暴雨气候特征 统计了1972—1981年6—8月份全区八个台站的降水资料,凡本地区日降水量有一站≥100mm,两站≥50mm,即作为一次全区     

遵义地区5—8月暴雨天气系统特征

暴雨是遵义地区夏季常见的灾害性天气之一，本文对全区5～8月份暴雨的气候概况和天气系统特征进行统计分忻，为建立本区暴雨的预报方法提供依据．1暴雨的气候概况全区范围内当3站以上日降水量≥50mm时定为一次区域性暴雨天气过程。普查1981～1990年5～8月历史资料．10年中，该过程5月份共出现5次，6月份11次，7月份！0次，8月份7次。区域性暴雨天气最多的年份是1987年7次，最少的是1990年1次，详见表1．从表中可看出，6月份是暴雨集中的月份，6月中、下旬到7月份中旬是暴雨的高峰期．2失至影响系统民纪500hPa上全区33次暴雨的主要天气系统…     

吉林省单站暴雪特征分析及评估方法

利用吉林省50站1951—2007年逐日降水资料,对暴雪的时空分布规律和气候变化特征进行了分析,对单站暴雪采用等级、序位、异常气候重现期等方法进行了评估。结果表明：吉林省暴雪一般集中出现在11月上旬到11月下旬以及3月上旬至4月上旬,吉林省东南部地区以及四平大部、松原北部暴雪的气候倾向率呈上升的趋势,20世纪末以来,吉林省暴雪出现次数处于偏多阶段。对单站暴雪可以采用等级、序位、异常气候重现期等方法评估,这些方法实用可行,可以满足快速、及时评估等气象服务的需求。     

北京市1996-2007年住宅空调致冷耗能影响因素分析

 采用气象资料和经济统计资料,以北京市为例,分析了城镇住宅空调致冷耗能的影响因素。结果显示：在一定建筑设计标准下,直接影响城镇住宅空调致冷耗能的因子主要有降温强度、城镇人口数、人均住宅建筑面积和城镇家庭空调器拥有比例。总的来说,由于目前中国城市化进程的加速,城镇人口、人均住宅建筑面积、城镇空调器拥有比例在不断增加,因此,无论气候变暖或变冷,各地空调致冷耗能不可避免地在增加。在上述因子中,气候是目前为止唯一可能起到降低能耗作用的因子。对于城市化较快的北京市,由于城镇家庭空调器拥有比例的快速增长,城镇家庭空调器拥有比例这一因子对空调致冷耗能增量的贡献率普遍最大。     

借鉴Holdridge生命地带分类系统方法分析内蒙古草原区域近50年气候变化特征

文章以Holdridge生命地带分类系统原理为指导,利用典型站点的气象资料,从气候的生物作用角度统计气候指标,并用该指标对内蒙古三种草原类型区域近50年的气候变化规律进行了分析。研究结果不仅反映了气候因子的综合变化规律,而且可以了解水热的综合变化对植被类型的可能影响。对探讨区域气候变化对植被演变的影响,合理利用气候资源,保护草原生态环境有一定的参考价值。     

田阳县1961—2010年日照时数气候变化特征分析

釆用气候倾向率和气候趋势系数对田阳县1961—2010年日照时数的年、季度资料进行分析,结果表明,田阳县近50a日照时数年、春季趋势减少明显,50a年日照时数气候倾向率为-35.532h/10a,春季气候倾向率为-14.944h/10a,夏、秋、冬季趋势减少不显著。     

乌审旗近50a气候变化特征分析

文章通过对乌审旗1961—2010年气温及降水资料进行分析,揭示了近50a来乌审旗气候变化特征,结果表明:近50a,乌审旗年平均气温呈明显上升趋势,四季温度变化对年平均气温上升贡献:冬季春季秋季夏季;年降水量呈微弱下降态势。在全球气候变暖的背景下,乌审旗气温上升,降水量减少,气候有向暖干化发展的趋势。     

应用模糊数学原理作七月份大—暴雨预报的尝试

七月份是我县暴雨集中月份,占全年大—暴雨的50％,成灾暴雨,也大都集中在七月份。我们分析了大—暴雨的气候规律,运用模糊数学理论,分型建立了预报未来24小时有无大—暴雨的隶属函数,找出了指标,应用中收到了较好的效果。     

最优气候均态法与最优气候相似法的应用比较

介绍了最优气候均态法与最优气候相似法这两种短期气候预测方法,并运用这两种预报方法对江门市2003~2006年12月份降水量进行了预报应用,得出了一些结论。     

新疆近50,a气候的变化特征

利用新疆地区具有较好代表性的23个气象台站1960-2009年的历史气候资料,运用线性倾向估计对新疆地区近50 a来气候变化的主要特征进行了分析.结果表明：近50 a来,新疆地区能量供给因子中的最高、最低和平均温度都呈明显的上升趋势,而日照时数、温度年较差呈明显的下降趋势,云量的变化趋势不明显并略有下降;空气动力因子风速的下降趋势显著;湿度因子中空气相对湿度和降水量略有上升趋势,而水汽压有明显上升趋势.受此影响,近50 a新疆地区气候总体趋于干向湿发展的趋势,气候朝暖湿方向变化.     

1961-2010年广东省高温天气时空变化特征分析

利用广东省27个地面观测站1961-2010年的日平均气温、日最高气温以及日最低气温等观测资料,采用线性倾向、Morlet小波分析、Mann-Kendall突变检验、EOF及REOF等统计方法,分析了广东省高温天气的气候变化特征。结果表明：广东省多年平均高温日数由北向南递减,并且递减趋势明显;近50 a广东省各地区的高温日数基本为上升趋势,中部高温日数的上升幅度最为明显;从全省平均情况来看,高温日数长期演变为显著的上升趋势,在20世纪90年代末之前处于偏少期,90年代末期以后进入偏多期,2005年后高温日数上升趋势较为显著;高温日数在1998年出现了突变现象;高温日数存在20-23 a的振荡周期,但这种周期性变化并不显著;广东省高温日数的标准化距平场可分为中部、北部和南部3区。     

田阳气温的气候变化特征及农业生产对策

通过对田阳县1960—2009年气温的统计,引用气候倾向率、气候趋势系数作分析。结果表明,田阳50a来年平均气温有明显变暖趋势,其增温变暖趋势值持平于全区、略低于全国的平均值。为了应对气候变暖提出了相应的农业生产对策。     

Does the model regional bias affect the projected regional climate change? An analysis of global model projections

An analysis is presented of the dependence of the regional temperature and precipitation change signal on systematic regional biases in global climate change projections. The CMIP3 multi-model ensemble is analyzed over 26 land regions and for the A1B greenhouse gas emission scenario. For temperature, the model regional bias has a negligible effect on the projected regional change. For precipitation, a significant correlation between change and bias is found in about 30% of the seasonal/regional cases analyzed, covering a wide range of different climate regimes. For these cases, a performance-based selection of models in producing climate change scenarios can affect the resulting change estimate, and it is noted that a minimum of four to five models is needed to obtain robust precipitation change estimates. In a number of cases, models with largely different precipitation biases can still produce changes of consistent sign. Overall, it is assessed that in the present generation of models the regional bias does not appear to be a dominant factor in determining the simulated regional change in the majority of cases.     

Variability and trends of sub-continental scale surface climate in the twentieth century. Part I: observations

An analysis is presented of observed temperature and precipitation variability and trends throughout the twentieth century over 22 land regions of sub-continental scale. Summer, winter and annual data are examined using a range of variability measures. Statistically significant warming trends are found over the majority of regions. The trends have a magnitude of up to 2 K per century and are maximum over cold climate regions. Only a few precipitation trends are statistically significant. Regional temperature and precipitation show pronounced variability at scales from interannual to multidecadal, with maximum over cold climate regions. The interannual variability shows significant variations and trends throughout the century, the latter being mostly negative for precipitation and both positive and negative for temperature. Temperature and precipitation anomalies show a chaotic-type behavior in which the regional conditions oscillate around the long term mean trend and occasionally fall into long-lasting (up to 10 years or more) anomaly regimes. A generally modest temporal correlation is found between anomalies of different regions and between temperature and precipitation anomalies for the same region. This correlation is mostly positive for temperature in cases of adjacent regions or regions in the same latitude belts. Several cases of negative inter-regional precipitation anomaly correlation are found. The ENSO significantly affects the anomaly variability patterns over a number of regions, primarily in tropical areas, while the NAO significantly affects the variability over northern mid- and high-latitude regions of Europe and Asia.     

气候变化国家评估报告(Ⅰ):中国气候变化的历史和未来趋势

The climate change in China shows a considerable similarity to the global change, though there still exist some significant differences between them. In the context of the global warming, the annual mean surface air temperature in the country as a whole has significantly increased for the past 50 years and 100 years, with the range of temperature increase slightly greater than that in the globe. The change in precipitation trends for the last 50 and 100 years was not significant, but since 1956 it has assumed a weak increasing trend. The frequency and intensity of main extreme weather and climate events have also undergone a significant change. The researches show that the atmospheric CO2 concentration in China has continuously increased and the sum of positive radiative forcings produced by greenhouse gases is probably responsible for the country-wide climate warming for the past 100 years, especially for the past 50 years. The projections of climate change for the 21st century using global and regional climate models indicate that, in the future 20-100 years, the surface air temperature will continue to increase and the annual precipitation also has an increasing trend for most parts of the country.     

MM5对末次盛冰期中国气候的模拟研究Ⅱ:海陆分布、植被和大尺度环流背景变化的影响

利用全球模式CCM3嵌套区域模式MM5的方法研究了末次盛冰期海陆分布、植被和大尺度环流背景场变化对末次盛冰期气候变化的作用。模式结果表明:与现代相比,末次盛冰期东亚地区海陆分布发生的变化造成这一地区冬季减温,夏季增温,这个变化对中国东部近海地区的温度和降水产生明显的影响,尤其是对降水的影响。它使得中国东部地区降水减少,由此造成的降水减少占末次盛冰期降水减少的25%—50%。海陆分布的变化对内陆和中国西部地区影响很小。末次盛冰期中国东部地区植被发生了明显的变化,温带和寒带植物南移,热带植物的覆盖范围减少。中国东部地区植被的巨大变化对温度产生了影响,使该地区冬季增温,夏季减温,年平均温度变化不大。末次盛冰期全球气候发生巨大的变化,即大尺度环流背景场变化。它使得中国地区的温度和降水产生显著变化,这个变化造成中国地区温度降低,并且决定了温度变化的主要分布和变化特征,东北地区是中国末次盛冰期降温最大的地区,青藏高原的降温超过同纬度的东部地区等。同时,大尺度背景场的变化还控制着降水的变化,末次盛冰期中国西部地区和东北地区降水的变化几乎完全是背景场变化引起的,其对华北和华东地区降水的影响大约为50%—75%。综合我们研究的影响末次盛冰期中国地区气候变化的因子,按影响程度由大到小排序为:大尺度环流背景场、海陆分布变化、植被变化、CO2浓度变化和地球轨道参数变化。     

MM5 Simulations of the China Regional Climate During the LGM.Ⅱ: Influence of Change of Land Area, Vegetation, and Large-scale Circulation Background

Using a regional climate model MM5 nested to an atmospheric global climate model CCM3, a series of simulations and sensitivity experiments have been performed to investigate the relative LGM climate response to changes of land-sea distribution, vegetation, and large-scale circulation background over China.Model results show that compared with the present climate, the fluctuations of sea-land distribution in eastern Asia during the LGM result in the temperature decrease in winter and increase in summer. It has significant impact on the temperature and precipitation in the east coastal region of China. The impact on precipitation in the east coastal region of China is the most significant one, with 25%-50% decrease in the total precipitation change during the LGM. On the other hand, the changes in sea-land distribution have less influence on the climate of inland and western part of China. During the LGM, significant changes in vegetation result in temperature alternating with winter increase and summer decrease, but differences in the annual mean temperature are minor. During the LGM, the global climate, i.e., the large-scale circulation background has changed significantly. These changes have significant influences on temperature and precipitation over China. They result in considerable temperature decreases in this area, and direct the primary patterns and characteristics of temperature changes. Results display that, northeastern China has the greatest temperature decrease, and the temperature decrease in the Tibetan Plateau is larger than in the eastern part of China located at the same latitude. Moreover, the change of large-scale circulation background also controls the pattern of precipitation change. Results also show that, most of the changes in precipitation over western and northeastern parts of China are the consequences of changing large-scale circulation background, of which 50%-75% of precipitation changes over northern and eastern China are the results of changes in large-scale circulation background. Over China, the LGM climate responses to different mechanisms in order of strength from strong to weak are, the large-scale circulation pattern, sea-land distribution, vegetation, CO2 concentration, and earth orbital parameters.     

The construction of oxygen isotope chronologies from tree-ring series sampled at different temporal resolution and its use as climate proxies: statistical aspects

Tree-ring oxygen stable isotope data series from conifers growing on the Dachstein Plateau (Austrian Alps) were selected to demonstrate the applicability of the serial pooling method using shifted 5-year tree-ring blocks for summer temperature reconstruction. The addressed method allows the construction of long isotope chronologies with significant climate correlation and well preserved climate sensitivity applying the irreducible sample replication of five trees. The linear regression model for temperature reconstruction is verifiable and the predicted data are well correlated with instrumental data, especially reproducing the long-term temperature trend. However, the reduced mean variance leads to loss of extreme years, which can be regulated by the combination of one data series in annual resolution with five shifted 5-year block data series. This significantly improves the variance of the mean chronology, sufficiently to identify extremes. Therefore, we recommend the use of mixed data sets as a compromise between essential sample replication and economic considerations.     

气候变化国家评估报告（Ⅰ）：中国气候变化的历史和未来趋势

 中国的气候变化与全球变化有相当的一致性，但也存在明显差别。在全球变暖背景下，近100 a来中国年平均地表气温明显增加，升温幅度比同期全球平均值略高。近100 a和近50 a的降水量变化趋势不明显，但1956年以来出现了微弱增加的趋势。近50 a来中国主要极端天气气候事件的频率和强度也出现了明显的变化。研究表明，中国的CO2年排放量呈不断增加趋势，温室气体正辐射强迫的总和是造成气候变暖的主要原因。对21世纪气候变化趋势做出的预测表明：未来20～100 a，中国地表气温增加明显，降水量也呈增加趋势。     

MM5 Simulations of the China Regional Climate During the LGM.II: In uence of Change of Land Area, Vegetation, and Large-scale Circulation Background

Using a regional climate model MM5 nested to an atmospheric global climate model CCM3, a series of simulations and sensitivity experiments have been performed to investigate the relative LGM climate response to changes of land-sea distribution, vegetation, and large-scale circulation background over China.Model results show that compared with the present climate, the fluctuations of sea-land distribution in eastern Asia during the LGM result in the temperature decrease in winter and increase in summer. It has significant impact on the temperature and precipitation in the east coastal region of China. The impact on precipitation in the east coastal region of China is the most significant one, with 25%-50% decrease in the total precipitation change during the LGM. On the other hand, the changes in sea-land distribution have less influence on the climate of inland and western part of China. During the LGM, significant changes in vegetation result in temperature alternating with winter increase and summer decrease, but differences in the annual mean temperature are minor. During the LGM, the global climate, i.e., the large-scale circulation background has changed signi cantly. These changes have signi cant influences on temperature and precipitation over China. They result in considerable temperature decreases in this area, and direct the primary patterns and characteristics of temperature changes. Results display that, northeastern China has the greatest temperature decrease, and the temperature decrease in the Tibetan Plateau is larger than in the eastern part of China located at the same latitude. Moreover, the change of large-scale circulation background also controls the pattern of precipitation change. Results also show that, most of the changes in precipitation over western and northeastern parts of China are the consequences of changing large-scale circulation background, of which 50%-75% of precipitation changes over northern and eastern China are the results of changes in large-scale circulation background. Over China, the LGM climate responses to di erent mechanisms in order of strength from strong to weak are, the large-scale circulation pattern, sealand distribution, vegetation, CO2 concentration, and earth orbital parameters.