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1.
2005年6月22日~23日长治市出现了历史罕见的高温酷热天气,针对此次过程,本文分析了500hPa、地面天气形势的演变特征。对高温强度的分布进行了探讨,为预报高温提供了气候背景,并提出了高温天气预报的着眼点。充分应用数值预报产品、850hPa高空指标站及本站14时气温资料的高温预报指标,在21日准确及时的发布了高温预警信号,提出了御防高温的措施建议,起到了积极的防灾减灾气象保障作用。  相似文献   

2.
Two weather records kept at Nassau, Bahamas, from 1811 to 1837, and from 1838 to 1845, respectively, are analyzed and compared to 20th century reference periods. The average annual temperature of the period is 24.2°C (±0.65°C), which is 0.4°C lower than 1961–1990 and 0.1°C lower than 1901–1920, the coolest period in the 20th century. Cold periods occurred from 1812–1819 and 1835–1839. A warmer phase prevailed between these two episodes and another warm episode occurred in 1840–1842. Temperature fell after the volcanic eruptions of Tambora (April, 1815) and Coseguina (January, 1835). The maximum cooling after Tambora is estimated at 1.0°C (±0.56°) and after Coseguina is estimated at 0.4°C (±0.56°). The post-Tambora cooling is in line with previous estimates (Robock, personal communication). The 1810s were a period of extreme drought at Nassau and are unequalled in later years. Rainfall frequency was below contemporary (1812–1837) averages from 1812–1820 and 1836–1837 but was above average from 1821–1835. Moist (dry) periods occurred almost simultaneously with warm (cool) periods. The months of October, November, and April show the greatest (negative) deviations in precipitation frequency. Gale force winds were 85% more frequent than from 1901–1960. Much of this increase took place in the months of September through November and represents an increase in tropical cyclone frequency in the Nassau area above that of 1901–1960. Resultant winds show a tendency towards greater northerly components than in the 20th century, especially during the winter months. The increase in northerly wind components, temperatures below the 20th-century average, and reduction in rainfall frequency in the winter half of the year indicates a synoptic situation in which high pressure was more frequent over the southeast North American continent.  相似文献   

3.
This article reviews evidence for 16th century glacial fluctuations in the western Swiss and the French Alps. Previously available sources and new historical sources, as well as dendrochronological investigations of larches that were destroyed by glacier advances (Great Aletsch Glacier), have shed much light in recent years on glacial movements in the 16th century. Many of the earliest know Records for glacial activity in the Western Alps date from the end of the 16th century and refer to outbursts of glacier dammed lakes (Allalin Glacier, Giétro Glacier, Rutor Glacier). Only few but very important evidence in the first half of the 16th century refer directly to glacial extension as in the case of the Lower Grindelwald Glacier and the Rhone Glacier. The drastic change in climate starting in 1565 which cause the remarkable advance of Alpine glaciers can be easily seen in the tree-ring curves (maximum density, tree ring width) of larches (Larix decidua Mill.) in the Alps.  相似文献   

4.
“97-11-24”和“97-11-27”大暴雨过程诊断分析   总被引:1,自引:1,他引:0  
利用T106物理量资料,对1997年11月24日和1997年11月27日两次江西大暴雨过程进行了诊断分析,并与夏季大暴雨的物理量特征进行了比较,得到了江西冬季产生大暴雨的物理条件,为冬季暴雨预报提供一些参考。  相似文献   

5.
SO2 emissions have been declining in China recently. The emission reduction has mainly been achieved engineering reduction, structural reduction, and administrative reduction. In this paper, three key industries (electricity generation, steel, and cement) are selected to measure the effects of SO2 emission reductions, the synergy effects of energy saving, and CO2 emission reduction. The main results show that, during the period of the ‘11th Five-Year Plan’, engineering reduction of coal-fired power plant desulfurization played the most crucial role in the emission reduction; both engineering reduction and structural reduction can achieve low-pollution emission, but the contributions are not the same due to the divergence of relevant industries. Generally speaking, structural reduction can relatively easily achieve the synergy effect of the main pollutants and GHGs; in comparison, however, engineering reduction does not easily achieve the synergy effect. During the ‘13th Five-Year Plan’ period, the following plans are proposed: strengthening the front pollution control, increasing the engineering reduction, narrowing the difference between the pollution reduction engineering ability and the actual pollution reduction effect, and strengthening the supervisory and administrative effect of both the approval of the front end and the running of the middle end.

POLICY RELEVANCE

China is on the way to realize industrialization and urbanization. The climate-friendly environmental protection strategy is particularly important for rapidly developing countries such as China, because it can address air pollution and climate change issues at the same time in a more economically efficient manner. This paper selects three key industries to evaluate current pollutant control policy synergy effect from the ‘11th Five-Year Plan’ to the ‘12th Five-Year Plan’ period in order to give more sense to policy makers during 13th Five-Year Plan. The estimate of this study shows that the control of pollutants can generally have synergic control effects on GHG emissions and give detailed measures for 13th Five-Year Plan.  相似文献   


6.
Coupled Model Simulations of Climate Changes in the 20th Century and Beyond   总被引:10,自引:1,他引:9  
Several scenario experiments of the IPCC 4th Assessment Report (AR4) are performed by version g1.0 of a Flexible coupled Ocean-Atmosphere-Land System Model (FGOALS) developed at the Institute of Atmospheric Physics, Chinese Academy of Sciences (IAP/CAS), including the "Climate of the 20th century experiment", "CO2 1% increase per year to doubling experiment" and two separate IPCC greenhouse gases emission scenarios AIB and B1 experiments. To distinguish between the different impacts of natural variations and human activities on the climate change, three-member ensemble runs are performed for each scenario experiment. The coupled model simulations show: (1) from 1900 to 2000, the global mean temper- ature increases about 0.5℃ and the major increase occurs during the later half of the 20th century, which is in consistent with the observations that highlights the coupled model's ability to reproduce the climate changes since the industrial revolution; (2) the global mean surface air temperature increases about 1.6℃ in the CO2 doubling experiment and 1.5℃ and 2.4℃ in the A1B and B1 scenarios, respectively. The global warming is indicated by not only the changes of the surface temperature and precipitation but also the temperature increase in the deep ocean. The thermal expansion of the sea water would induce the rise of the global mean sea level. Both the control run and the 20th century climate change run are carried out again with version g1.1 of FGOALS, in which the cold biases in the high latitudes were removed. They are then compared with those from version g1.0 of FGOALS in order to distinguish the effect of the model biases on the simulation of global warming.  相似文献   

7.
对1997年11月24日和1997年11月27日两次江西大暴雨过程的T106物理量预报场进行了分析,得到T106物理量场对稳定切变的暴雨形势有较好的预报能力等一些有意义的结果。  相似文献   

8.
利用WRF模式对2012年8月17~18日四川出现的一次大暴雨过程进行模式模拟和诊断分析,并通过对地形敏感性试验讨论川西高原至川东过渡带陡峭地形对此次暴雨的影响。结果表明,WRF基本成功模拟出2012年8月中旬四川中部大暴雨过程,对环流形式预报与实况较为一致。此次过程水汽来源台风低压及副高外围携带的水汽。川中云团发展阶段对应四川中部多个站出现强降水,该对流云团发展是引发本次降水的重要因素,而对流层中低层高温高湿环境对对流云团发展提供有力的环境。地形敏感性试验表明,陡峭地形高度与降水强度呈正比,通过影响陡峭地形周边物理量特征场分布从而影响暴雨区降水强度;相对湿度的影响小于温度对降水强度的影响作用。  相似文献   

9.
Flood risks of deltaic areas increase because of population growth, economic development, land subsidence and climatic changes such as sea-level rise. In this study, we analyze trends in flood exposure by combining spatially explicit historical, present, and future land-use data with detailed information on the maximum flood inundation in the Netherlands. We show that the total amount of urban area that can potentially become inundated due to floods from the sea or main rivers has increased six-fold during the 20th century, and may double again during the 21st century. Moreover, these developments took, and probably will take, place in areas with progressively higher potential inundation depths. Potential flood damage has increased exponentially over the 20th century (16 times) and is expected to continue to increase exponentially (∼ten-fold by 2100 with respect to 2000) assuming a high economic growth scenario. Flood damages increase more moderately (two- to three-fold by 2100 with respect to 2000) assuming a low growth scenario. The capacity to deal with catastrophic flood losses - expressed as the ratio damage/GDP - will, however, decrease slightly in the low growth scenario (by about 20%). This trend deviates from the historical trend of the 20th century, which shows an increasing capacity to cope with flood damage (almost doubling). Under the high growth scenario the capacity to deal with such losses eventually increases slightly (by about 25%). These findings illustrate that, despite higher projections of potential flood damage, high economic growth scenarios may not necessarily be worse than low growth scenarios in terms of the impact of floods.  相似文献   

10.
Tornadoes have occurred in the territory of the Czech Republic throughout history. Although their frequency and intensity are not as high as in the USA, they can cause severe damage as well. That is why a systematic effort to document individual occurrences of this dangerous meteorological phenomenon as far as possible back into the past began in the 1990s. The aim of this investigation is to extend the first European catalogue of tornadoes originally published by Wegener [Wegener A., 1917. Wind-und Wasserhosen in Europe], by the addition of these cases from the Czech Republic.This paper adds further to Setvák, Šálek and Munzar [Setvák M., Šálek M., Munzar J., 2003. Tornadoes within the Czech Republic—from medieval chronicles to the internet society. Atmos. Res. 67–68, 589–605], who reported the earliest documented tornado in the land of the Czech Republic which occurred in AD 1119 in Prague. In so doing, it presents recently discovered tornado cases from the 16th to the early 20th centuries, found in a variety of historical sources since the last ECSS conference held in Prague in 2002. In particular we will focus on the case from Jablonec nad Nisou (northern Bohemia) in 1925, which was probably the first case in the Czech Republic with accompanying photographic documentation of damage caused by a tornado.  相似文献   

11.
Breakup and freezeup dates for the Red River at Winnipeg, Manitoba, Canada, were compiled from archival sources for the period from 1815 to the beginning of published data in 1908. Median 19th C dates of freezeup and break-up were 12 and 10 days earlier and later respectively than during the 20th C, and the average ‘ice-in’ season was nearly three weeks longer. Correlation of breakup and freezeup dates with spring and fall temperatures suggests that both seasons were about 25 °C cooler in the 19th C than in the 20th. The change appears to have occurred rapidly at the end of the 19th C.  相似文献   

12.
十一运会期间雷电灾害风险评估   总被引:1,自引:0,他引:1  
朱桂林  李永果  李燕 《气象科技》2010,38(Z1):93-96
对1959—2008年10月山东各地雷电日数进行了分析,以山东的地貌特征、雷电发生的频率、人口密度和十一运会赛事场馆所在区域为评价因子,采用模糊数学方法分别计算出不同区域的孕灾环境敏感度、灾害发生的危险性和城市脆弱性3种指数,建立了山东地区十一运会期间雷电灾害风险评估模型,并在此基础上客观地划分等级,最后得到了山东地区十一运会期间雷电灾害的风险分级及其区划。  相似文献   

13.
Abstract

Trends in Canadian temperature and precipitation during the 20th century are analyzed using recently updated and adjusted station data. Six elements, maximum, minimum and mean temperatures along with diurnal temperature range (DTR), precipitation totals and ratio of snowfall to total precipitation are investigated. Anomalies from the 1961–1990 reference period were first obtained at individual stations, and were then used to generate gridded datasets for subsequent trend analyses. Trends were computed for 1900–1998 for southern Canada (south of 60°N), and separately for 1950–1998 for the entire country, due to insufficient data in the high arctic prior to the 1950s.

From 1900–1998, the annual mean temperature has increased between 0.5 and 1.5°C in the south. The warming is greater in minimum temperature than in maximum temperature in the first half of the century, resulting in a decrease of DTR. The greatest warming occurred in the west, with statistically significant increases mostly seen during spring and summer periods. Annual precipitation has also increased from 5% to 35% in southern Canada over the same period. In general, the ratio of snowfall to total precipitation has been increasing due mostly to the increase in winter precipitation which generally falls as snow and an increase of ratio in autumn. Negative trends were identified in some southern regions during spring. From 1950–1998, the pattern of temperature change is distinct: warming in the south and west and cooling in the northeast, with similar magnitudes in both maximum and minimum temperatures. This pattern is mostly evident in winter and spring. Across Canada, precipitation has increased by 5% to 35%, with significant negative trends found in southern regions during winter. Overall, the ratio of snowfall to total precipitation has increased, with significant negative trends occurring mostly in southern Canada during spring.

Indices of abnormal climate conditions are also examined. These indices were defined as areas of Canada for 1950–1998, or southern Canada for 1900–1998, with temperature or precipitation anomalies above the 66th or below the 34th percentiles in their relevant time series. These confirmed the above findings and showed that climate has been becoming gradually wetter and warmer in southern Canada throughout the entire century, and in all of Canada during the latter half of the century.  相似文献   

14.
基于《气象与环境学报》创刊25周年之际,从期刊栏目设置、编辑工作、出版发行、办刊成绩、编辑质量、编排标准和期刊影响因子、网络传播及编辑现代化建设等方面进行了全面回顾;据29种大气科学(气象学)期刊被引统计数据表明:《气象与环境学报》2008年影响因子为1.313,排序为第11名;并展望了未来期刊发展方向,按照“核心期刊”的发展思路,要进一步提高办刊质量,以适应目前文化体制改革方向,更好地发展与创新。  相似文献   

15.
Changes of Air–sea Coupling in the North Atlantic over the 20th Century   总被引:1,自引:0,他引:1  
Changes of air–sea coupling in the North Atlantic Ocean over the 20 th century are investigated using reanalysis data,climate model simulations, and observational data. It is found that the ocean-to-atmosphere feedback over the North Atlantic is significantly intensified in the second half of the 20 th century. This coupled feedback is characterized by the association between the summer North Atlantic Horseshoe(NAH) SST anomalies and the following winter North Atlantic Oscillation(NAO). The intensification is likely associated with the enhancement of the North Atlantic storm tracks as well as the NAH SST anomalies. Our study also reveals that most IPCC AR4 climate models fail to capture the observed NAO/NAH coupled feedback.  相似文献   

16.
In our paper we analyze the influence of climatic changes on annual price fluctuations (harvest year) of agricultural products in Germany during the 16th century price revolution. The price series under analysis are from Nuremberg, Cologne, Augsburg, and Munich. The prices are compared with quarterly climatic indices for Germany, which cover the observation period 1500-1599. The main finding is that the length of the vegetation period is an important factor in determining grain price fluctuations. During the climatic deterioration in the 16th century, there is some evidence that the impact of climate (and therefore of supply fluctuations) on grain price fluctuations increases.  相似文献   

17.
This work was focused on the assessment of changes occurring in crop production and climate during the 20th century in Argentina. The study was carried out for nine sites located in the Pampas region that are representative of contrasting environments. We have considered the four main crops cultivated in this area (wheat, maize, sunflower and soybean). Historical climatic data and crop production related variables (yield, planted area, harvested area) were analyzed and, by means of crop simulation models, we quantified the impact of climate on crop yields. Changes occurring in climate during the three last decades of the 20th century were characterized by important increases in precipitation especially between October and March, decreases in maximum temperature and solar radiation in particular during spring and summer and increases in minimum temperature during almost all of the year. These changes contributed to increases in yields, especially in summer crops and in the semiarid zone, mostly due to increases in precipitation, although changes in temperature and radiation also affected crop yields but to a lesser extent. Comparing the period 1950–1970 with 1971–1999, yields increases attributable to changes in climate were 38% in soybean, 18% in maize, 13% in wheat, and 12% in sunflower while mean observed yield increases were 110% for maize, 56% for wheat and 102% for sunflower.  相似文献   

18.
十一运会WRF RUC系统应用及典型个例评估   总被引:1,自引:0,他引:1  
第十一届全国运动会期间,山东省气象局引进了北京奥运气象科技成果"北京快速循环同化系统"(BJ-RUC),建立了山东区域的WRF-RUC系统,开发了十一运会精细化数值预报产品。文章介绍了该系统的业务运行方案和流程,并以十一运会开幕式保障服务过程为主,对WRF-RUC不同水平分辨率的站点预报结果、WRF-RUC模式场馆要素精细预报、模式不同起报时间的预报结果进行了检验评估,最后与山东省气象局业务运行的MM5、ARPS模式的预报结果进行了对比分析,评估结果对于预报员更好地使用数值模式产品具有很好的指导意义。  相似文献   

19.
哈密地区7·17暴雨天气过程分析   总被引:6,自引:0,他引:6  
对2007年7月16—19日哈密暴雨天气过程的分析表明:这次暴雨是伊朗副高北伸,里咸海长脊,与乌拉尔山高压脊反气旋型接通,推动中亚低涡东移进入新疆,在哈密滞留造成的。深厚的低值系统从低层到中层都表现为强的辐合上升运动,为暴雨产生提供很强的动力条件,有利于暴雨所需不稳定能量的储存,低层风场辐合及中高层强西南气流不断将水汽输送至暴雨区,为暴雨提供充足的水汽,冷暖、干湿空气的水平、垂直交换等在暴雨中激发大量不稳定能量的释放加强了对流,这都是暴雨产生的直接有利条件,欧洲数值预报产品、T213物理量场和FY-2红外云图进行暴雨天气预报具有较好的指导意义。  相似文献   

20.
对2006年7月17日锡林郭勒盟南部地区及苏尼特右旗的暴雨和大暴雨天气过程进行了天气诊断分析,结果表明:7月17日暴雨的产生是地面倒槽、高低空急流、切变线、副热带高压共同作用的结果。高空500hPa稳定的环流形势为大暴雨的酝酿提供了有利的环流背景,低层切变线、冷空气是暴雨产生的触发条件,而台风低压的滞留为暴雨区提供了源源不断的水汽和动力抬升条件。  相似文献   

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