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1.
近五十年来广西海岛的气候变化与气象灾害特征分析   总被引:1,自引:0,他引:1  
利用涠洲岛气象站自建站至2010年的气象观测资料,分析总结近五十年来广西海岛的气候特征、气候变化规律与气象灾害特征。分析结果表明,随着全球变暖广西海岛的气候发生了明显变化,气温显著升高,特别是90年代后期以来,升温更加显著,冬季对气候变暖的贡献最大;年降水量呈增多趋势,主要来自夏季降水量增多的贡献,从80年代开始降水量增加趋势明显;广西海岛主要的气象灾害发生的频率和强度出现明显变化,台风影响个数略有减少,大风日数呈减少趋势,暴雨、旱涝灾害有所增加,极端天气气候事件造成的灾害损失呈增大趋势。  相似文献   

2.
通过对鹤壁市43 a夏玉米生育期间气象要素线性趋势以及其不同年代的均值、变异系数(C·V)、距平变化分析,揭示了在全球气候变暖背景下鹤壁市夏玉米生育期间气候条件的变化规律:活动积温和降水量分别在1993年和1977年前后发生气候突变,降水量由增加趋势转变为减少趋势,活动积温由减少趋势转变为增加趋势;全生育期间及各生育期的活动积温均呈缓慢增多趋势;播种期和苗期发生初夏旱几率高于全省平均水平,影响到玉米的适时播种和出苗;全生育期间日照时数的年际变化与各生育期间的日照时数变化趋势均呈现出随年份逐渐减少趋势,但仍属气候正常振动.  相似文献   

3.
 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。  相似文献   

4.
宁夏气温、降水、蒸发的变化及其对气候变暖的响应   总被引:38,自引:0,他引:38  
本文对近40多a来宁夏气温、降水、小型蒸发皿蒸发量的变化进行了分析,结果表明:宁夏年平均气温具有明显的年代际变化特征,1986年附近发生了一次明显气候跃变,跃变后增温最明显的是冬季;秋季降水量的年代际变化特征较明显,在1978年发生转折,此前宁夏处于多雨时段,其后处于降水偏少的气候背景之中;宁夏小型蒸发皿蒸发量近40 a来存在下降趋势,下降趋势最明显的季节是夏季,最明显的区域是宁南山区;近年来宁夏蒸发量的减少与太阳辐射的减弱及水汽压的增加有关,宁南山区蒸发明显下降,与低云量的减少有关;宁夏平均气温对中国区域气候变暖响应明显,当中国区域平均气温增加1℃(各季及年),宁夏春季平均气温约升高1.1℃,夏、秋、冬季及年平均气温约升高1.3℃;宁夏春季降水量与中国区域同期降水量有密切联系;在全球气候变暖的大背景下,宁夏秋季降水有下降趋势,冬季降水存在上升趋势;宁夏气候有变干的趋势。  相似文献   

5.
湖南气候对全球气候变化的响应   总被引:4,自引:0,他引:4       下载免费PDF全文
利用湖南省96个台站1960—2010年逐日气象观测资料,在进行均一性检验和订正的基础上对湖南省气候变化事实进行检测分析。结果表明:湖南气候与全球气候变化一致,呈现以变暖为主要特征的变化,且变暖存在季节、地域上的差异,冬、春、秋气温变暖趋势显著,增暖幅度最大的区域在湘北地区;对气候变暖响应敏感的要素主要是与平均气温、冬季气温相关密切的要素,如季平均气温、年平均最低气温、活动积温等;湖南气温在突变时间上具有较好的时间逻辑关系;湖南降水量无显著趋势变化,但极端降水增加,地域性差异明显,湖南东部地区降水量呈现明显增加趋势,日降水量大于等于100 mm的日数呈显著增加趋势;湖南日照时数、风速、相对湿度均呈现显著减少的变化趋势。  相似文献   

6.
根据生产实践,影响广东冬种生产的主要气象灾害为寒害、干旱、低温阴雨。从程度和频度两个方面分析气候变暖前后1961—1996年与1997—2015年两个时段广东冬种生产季气象灾害变化特征。结果表明,1997年以来(气候变暖后),(1)寒害、低温阴雨均呈明显减弱趋势,为冬种生产提供了更为有利的气候条件;(2)寒害偏重发生频率明显减弱,广东大部分地区处在频率 < 30%的区域;(3)干旱偏重发生频率增加,其中频率>30%的区域有所增加,主要分布在粤北、潮汕、茂名和湛江等地区;(4)低温阴雨偏重发生频率明显减弱,广东大部分地区处在频率 < 30%的区域。   相似文献   

7.
1961—2006年云南可利用降水量演变特征   总被引:3,自引:0,他引:3       下载免费PDF全文
利用云南122个测站1961—2006年逐月降水量、气温观测资料,依据高桥浩一郎的陆面实际蒸散发经验公式,计算了云南可利用降水量,分析了全球气候变暖背景下云南可利用降水量的变化特征,获得了一些有意义的结果:1)近50年来云南可利用降水量在春季增加,而其余季节减少,特别是夏季可利用降水量明显减少,导致云南年可利用降水量明显减少。2)云南可利用降水量除冬季年代际变化不明显,年际变化明显外,其余季节及年可利用降水量都存在明显的年代际及年际变化。3)从区域趋势变化看,云南大部可利用降水量在冬、春季以增加为主;夏季以减少为主;秋季东部减少,西部增加;全年可利用降水量东部、南部以减少为主,其余地区以增加为主。4)年可利用降水量在全球气候偏暖年以偏少为主,而在偏冷年则以偏多为主。  相似文献   

8.
利用CMIP5耦合模式RCP2.6、RCP4.5和RCP8.5情景预估结果,以1890一1900年为基准气候,确定了2℃全球变暖时间、对应时期青藏高原平均气候和极端气候事件变化幅度,多模式集合平均结果表明:RCP2.6、RCP4.5和RCP8.5情景下2℃全球变暖分别发生在2063年、2040年和2036年;对应着2℃全球变暖,三种情景下青藏高原平均气温分别升高2.99℃、3.22℃和3.28℃,均超过全球2℃的升温水平;年降水量亦增加,分别增加8.35%、7.16%和7.63%。受气温升高和降水量增多影响,RCP4.5情景下霜冻日数、冰封日数减少,暖夜日数、暖昼日数增多;RCP4.5情景下中雨日数、强降水量、降水强度均增加,持续干期天数减少。从各地平均气候和极端气候事件变化结果来看,柴达木盆地是青藏高原气候变化的敏感区。  相似文献   

9.
近50年西江径流量变化与气候变暖关系   总被引:4,自引:6,他引:4  
利用西江流域年径流量资料、全球及西江流域历年气温和雨量资料,从气候变化角度出发,分析得出近50年西江实测径流量变化与气候变暖无直接关系,与流域的降水量变化关系明显.  相似文献   

10.
选取乌鲁木齐自建站到2007年的平均气温、最高气温、最低气温、降水量等年值资料,用SNHT方法进行均一性检验及订正,并采用气候趋势系数进行订正前后的气候趋势对比分析发现,乌鲁木齐平均气温、最低气温、最高气温在1975年,降水量分别在1958年和1975年因迁站而引起了资料的非均一性变化,其中降水量对台站的搬迁变化更加敏感。平均气温值长期变化订正后比订正前增加趋势更加明显,变暖幅度比订正前增大了1/3,比同期中国平均增温速率明显偏大,比全球或半球同期平均增温速率也明显偏大。降水量值长期变化订正后比订正前的增加趋势有所减弱,增加幅度比订正前减少了近一半,用西郊机场近几年的资料进行对比,也验证了这种结果。  相似文献   

11.
潮白河流域为北京主要供水源,其水资源量对北京用水保障至关重要,因此开展该流域在全球1.5℃和2.0℃升温下的径流预估研究具有现实意义。利用1961—2001年WATCH数据对SWAT水文模型进行率定和验证,在此基础上,应用第五次耦合模式比较计划(CMIP5)中5个全球气候模式在典型浓度路径(RCP4.5、RCP6.0和RCP8.5)下预估的全球1.5℃和2.0℃升温下的数据驱动SWAT模型,开展了潮白河流域气温、降水及径流量的变化预估研究,并量化评估由气候模式和RCPs导致的水文效应的不确定性。结果表明:(1) SWAT模型基本能较好地模拟潮白河流域的月径流特征,应用该模型进行气候变化对径流量的影响评估是可行的。(2)在全球1.5℃和2.0℃升温下,潮白河流域年平均温度较基准期(1976—2005年)分别增加1.5℃和2.2℃,年平均降水量也增加4.9%和7.0%。预估的年径流量在全球1.5℃升温下总体略有增加,盛夏和秋初的径流量占全年的比例也有所增加;在全球2.0℃升温下,年径流量增幅达30%以上,但夏季径流量占全年的比例明显减少。(3)在全球2.0℃升温下,潮白河流域极端丰水流量明显增加,洪涝发生风险增大。(4)未来气温、降水量和径流量的预估都存在一定的不确定性,在全球2.0℃升温下不确定性更大;相对而言,径流量的不确定性要远大于降水量的不确定性;无论是全球1.5℃升温下还是2.0℃升温下,预估不确定性主要来源于全球气候模式。  相似文献   

12.
Using a set of numerical experiments from 39 CMIP5 climate models, we project the emergence time for 4°C global warming with respect to pre-industrial levels and associated climate changes under the RCP8.5 greenhouse gas concentration scenario. Results show that, according to the 39 models, the median year in which 4°C global warming will occur is 2084. Based on the median results of models that project a 4°C global warming by 2100, land areas will generally exhibit stronger warming than the oceans annually and seasonally, and the strongest enhancement occurs in the Arctic, with the exception of the summer season. Change signals for temperature go outside its natural internal variabilities globally, and the signal-to-noise ratio averages 9.6 for the annual mean and ranges from 6.3 to 7.2 for the seasonal mean over the globe, with the greatest values appearing at low latitudes because of low noise. Decreased precipitation generally occurs in the subtropics, whilst increased precipitation mainly appears at high latitudes. The precipitation changes in most of the high latitudes are greater than the background variability, and the global mean signal-to-noise ratio is 0.5 and ranges from 0.2 to 0.4 for the annual and seasonal means, respectively. Attention should be paid to limiting global warming to 1.5°C, in which case temperature and precipitation will experience a far more moderate change than the natural internal variability. Large inter-model disagreement appears at high latitudes for temperature changes and at mid and low latitudes for precipitation changes. Overall, the inter-model consistency is better for temperature than for precipitation.  相似文献   

13.
Using a set of numerical experiments from 39 CMIP5 climate models, we project the emergence time for 4?C global warming with respect to pre-industrial levels and associated climate changes under the RCP8.5 greenhouse gas concentration scenario. Results show that, according to the 39 models, the median year in which 4?C global warming will occur is 2084.Based on the median results of models that project a 4?C global warming by 2100, land areas will generally exhibit stronger warming than the oceans annually and seasonally, and the strongest enhancement occurs in the Arctic, with the exception of the summer season. Change signals for temperature go outside its natural internal variabilities globally, and the signal-tonoise ratio averages 9.6 for the annual mean and ranges from 6.3 to 7.2 for the seasonal mean over the globe, with the greatest values appearing at low latitudes because of low noise. Decreased precipitation generally occurs in the subtropics, whilst increased precipitation mainly appears at high latitudes. The precipitation changes in most of the high latitudes are greater than the background variability, and the global mean signal-to-noise ratio is 0.5 and ranges from 0.2 to 0.4 for the annual and seasonal means, respectively. Attention should be paid to limiting global warming to 1.5?C, in which case temperature and precipitation will experience a far more moderate change than the natural internal variability. Large inter-model disagreement appears at high latitudes for temperature changes and at mid and low latitudes for precipitation changes. Overall, the intermodel consistency is better for temperature than for precipitation.  相似文献   

14.
全球变暖影响着以流域径流要素为主导的水文水资源系统的变化。长江流域未来水资源量的时空分布对长江大保护与长江经济带的发展意义重大。为探究全球升温1.5℃和2.0℃对长江流域径流变化的影响,使用基于偏差校正的气候模式集合数据驱动两参数月水量平衡模型,比较两种升温情景下径流量的响应差异。结果表明:基于偏差校正的气候模式集合数据可以较好地代表长江流域历史时期(1976—2005年)的年平均降水和年平均蒸散发情势。两参数月水量平衡模型与参数区域化方法相结合能较好地模拟长江流域各子流域的月径流量。升温1.5℃时,无论是年径流量还是季节径流量均呈上升趋势,与历史时期相比,50%以上三级子流域的增幅超过5%;升温2.0℃时,增幅超过8%。这表明升温2.0℃情景下长江流域水资源量将进一步增加。相对于历史时期,升温1.5℃与2.0℃情景下长江流域北部降水量增幅较大;径流量增幅分布格局基本与降水量一致。汉江流域是全流域径流量增幅最显著的区域。  相似文献   

15.
1.5和2℃升温阈值下中国温度和降水变化的预估   总被引:1,自引:0,他引:1  
基于CMIP5耦合气候模式模拟结果对1.5和2℃升温阈值时中国温度和降水变化的分析表明,1.5℃升温阈值时,中国年平均升温由南向北加强且在青藏高原地区有所放大,季节尺度上升温的空间分布与其类似,就区域平均而言,RCP2.6、RCP4.5和RCP8.5情景下中国年平均气温分别升高1.83、1.75和1.88℃,气温的季节变幅以冬季升高最为显著;除华南和西南地区外中国大部分地区年平均降水量增多,降水的季节差异明显,以夏季降水的分布模态与年平均降水量的分布最为相似,区域平均的年降水量分别增加5.03%、2.82%和3.27%,季节尺度上以冬季降水增幅最大。2℃升温阈值时,RCP4.5和RCP8.5情景下中国年平均温度的空间分布与1.5℃升温阈值基本一致,中国年平均气温分别升高2.49和2.54℃,季节尺度上气温的变化以秋、冬季增幅最大;中国范围内年平均降水量基本表现为增多趋势,其中,西北和长江中下游部分地区表现为明显的季节差异,区域平均的年降水量分别增加6.26%和5.86%。与1.5℃升温阈值相比较,2℃升温阈值时中国年平均温度在RCP4.5和RCP8.5情景下分别升高0.74和0.76℃,降水则分别增加3.44%和2.59%,空间上温度升高以东北、西北和青藏高原最为显著,降水则在东北、华北、青藏高原和华南地区增加最为明显。   相似文献   

16.
Created are the grid datasets of monthly mean and annual mean temperature as well of monthly, seasonal, and annual values of the total precipitation with the resolution of 25 km for the period of 1936–2011. The obtained datasets characterize the real picture of the spatial distribution of temperature and precipitation on the territory of Georgia; therefore, they are used for working out geoinformative maps of temperature and precipitation variations. Revealed are the areas and centers with different intensity of warming and cooling. It is found that the annual temperature and total annual precipitation averaged for the territory do not vary considerably under conditions of the global warming.  相似文献   

17.
《大气与海洋》2013,51(2):93-105
Abstract

Global warming due to increased greenhouse gases is believed to result in not only higher surface temperatures but also an acceleration of the hydrological cycle leading to increased precipitation. Although climate models consistently predict increases in global temperatures due to increasing greenhouse gases and the accompanying global warming, observations at the climatic timescales necessary to confirm the models are rare. Multidecadal studies at global and regional scales are necessary to determine whether the presently observed changes in temperature and precipitation are due to short‐term fluctuations or long‐term trends. In this study, we address this issue by examining changes in temperature and precipitation on Long Island, New York over a 74‐year time period (1931 to 2004) using a network of rain gauges and temperature measurements. The mean annual temperature on Long Island has increased at a rate of 0.05°C per decade, which is less than that of observed global values and is most likely due to the urban warming effects of New York City, not large‐scale climate change. The mean total annual precipitation has increased at a rate of 0.71 cm per decade during the study period, which is consistent with global observations. Intra‐annual temperature fluctuations are decreasing at a rate of 0.36% per decade, while precipitation variations are increasing at a rate of 0.91% per decade. Empirical orthogonal function analysis indicates that variations in temperature and precipitation on Long Island are dominated by island‐wide fluctuations that are directly related to the North Atlantic Oscillation, the Arctic Oscillation, and the El Niño Southern Oscillation.  相似文献   

18.
Trends in air temperature and precipitation data are investigated for linkages to global warming and climate change. After checking for serial correlation with trend-free pre-whitening procedure, the Mann–Kendall test is used to detect monotonic trends and the Mann–Whitney test is used for trend step change. The case study is Maharlo watershed, Southwestern Iran, representing a semi-arid environment. Data are for the 1951–2011 period, from four temperature sites and seven precipitation sites. A homogeneity test investigates regional similarity of the time series data. The results include mean annual, mean annual maximum and minimum and seasonal analysis of air temperature and precipitation data. Mean annual temperature results indicate an increasing trend, while a non-significant trend in precipitation is observed in all the stations. Furthermore, significant phase change was detected in mean annual air temperature trend of Shiraz station in 1977, indicating decreasing trend during 1951–1976 and increasing trend during 1977–2011. The annual precipitation analysis for Shiraz shows a non-significant decrease during 1951–1976 and 1977–2011. The result of homogeneity test reveals that the studied stations form one homogeneous region. While air temperature trends appear as regional linkage to global warming/global climate change, more definite outcome requires analysis of longer time series data on precipitation and air temperature.  相似文献   

19.
Because of the importance of the changes in the hydrologic cycle, accurate assessment of precipitation characteristics is essential to understand the impact of climate change due to global warming. This study investigates the changes in extreme precipitation with sub-daily and daily temporal scales. For a fine-scale climate change projection focusing on the Korean peninsula (20 km), we performed the dynamical downscaling of the global climate scenario covering the period 1971?C2100 (130-year) simulated by the Max-Planck-Institute global climate model, ECHAM5, using the latest version of the International Centre for Theoretical Physics (ICTP) regional climate model, RegCM3. While annual mean precipitation exhibits a pronounced interannual and interdecadal variability, with the increasing or decreasing trend repeated during a certain period, extreme precipitation with sub-daily and daily temporal scales estimated from the generalized extreme value distribution shows consistently increasing pattern. The return period of extreme precipitation is significantly reduced despite the decreased annual mean precipitation at the end of 21st century. The decreased relatively weak precipitation is responsible for the decreased total precipitation, so that the decreased total precipitation does not necessarily mean less heavy precipitation. Climate change projection based on the ECHAM5-RegCM3 model chain clearly shows the effect of global warming in increasing the intensity and frequency of extreme precipitation, even without significantly increased total precipitation, which implies an increased risk for flood hazards.  相似文献   

20.
Spatiotemporal regularities of changes in mean annual air temperature and annual precipitation amount values for the Belaya River basin were revealed on the basis of the analysis of statistical homogeneity of their long-term series. It is established that warming has occurred by now and the increase in precipitation amount is registered in the Belaya River basin. Revealed was the contribution of mean seasonal air temperature and precipitation changes to the changes in their mean long-term values.  相似文献   

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