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根据三峡水库坝区周边气候考察气象站1992-2004年和宜昌站1952-2004年的逐日气温资料,先用差值法将短期考察资料延长,再通过对比、回归等方法,客观分析了气温随时间和地形的变化规律,结果表明：1）三峡坝区具有冬暖、夏热等特点,是湖北的夏热和冬暖中心之一,不同高度气温年或日变化具有相同位相。2）平均气温、最高和最低气温、极端最低气温、气温日较差等指标随高度升高而递减,极端最低气温日数随高度升高而递增。3）水体对库周气温具有白天降温、夜间增温的效应,增温幅度比降温幅度大,增温幅度夏季大于冬季,降温幅度夏季小于冬季。4）三峡坝区20世纪90年代之前年平均气温呈波动变化,之后有显著上升趋势;水库蓄水以后对水域周围地区有降温效应。 相似文献
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陈丹 《沙漠与绿洲气象(新疆气象)》2020,14(4):94-99
采用一元线性回归分析和基于Matlab的Mann-kendal气候突变检验和morlet小波分析等方法，开展沙雅气象站50年常规气象要素和极端天气指数研究分析。结果显示：(1)气温增温趋势明显，最低气温上升对气温增温贡献大。(2)降水量变化趋势不明显，在20世纪80年代强度变化大。(3)历年日照时数显著下降，有高频振荡周期。(4)风速下降显著，春季风速下降速率最快；全年主导风向为东北风，除此之外夏季还多出现北风，秋冬季节多出现偏西风。(5)夜间最低气温增温明显，且增温速率高于白天，极端低温日数减少，沙雅县气温呈上升趋势；降水日数和各量级降水日数趋势变化不明显。 相似文献
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《内蒙古气象》2018,(6)
利用毕节市8个国家气象站1970-2015年的气温资料,分析探讨毕节市平均气温、年极端高温、年极端低温、寒冷日数、炎热日数以及近46a温度变化的特征。结果表明:毕节市近46a年平均气温呈显著升高趋势,其中秋季增温最显著,夏季增温最弱;极端气温分布体现毕节市独特的山地气候特征,极端最低气温主要分布在海拔较高的威宁、大方,极端最高气温则是分布在海拔较低的金沙等地,且随着增温趋势显著,毕节寒冷日数显著减少,炎热日数无明显变化。在突变分析中发现毕节市在年和春、秋季节气温显著升高,突变大多发生在2000年以后,在夏、冬季节气温也呈现升高趋势,但升温幅度较春、秋季节弱。 相似文献
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吉林省2006年夏季总的天气特点是一早、三多、三少、一高、两低，即雨季开始早；前夏（6月）降水多，雷暴日数多，局地暴雨多；仲夏（7月）降水少，前夏日照时数少，极端最高气温≥30℃日数少；后夏气温高；前夏（6月）和7月下旬气温低。部分地方出现了局地或区域性洪涝或内涝，部分县（市）发生了水稻障碍型冷害。 相似文献
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兰州最高最低气温的非对称变化 总被引：1，自引：1，他引：1
分析了兰州1932～2002年年平均气温、年平均最高和最低气温及年平均气温日较差的气候变化特征。分析表明：1932年以来，4个气温要素的线性增温率依次为每10年0．14℃、0．06℃、0．38℃、-0．32℃。兰州20世纪40年代最高气温对增暖的贡献大，80年代最低气温对增暖的贡献大，而90年代的异常偏暖表现为最高和最低气温的同时上升。另外，在40年代各季平均最高和最低气温均呈相反的趋势，表现为最高气温的上升和最低气温的下降；在1950～1970年间最高和最低气温的变化趋势和幅度非常接近，但维持时间各季略有不同；80年代以来，最低和最高气温均在上升，但最低气温的增温率明显高于最高气温的增温率。 相似文献
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中国地区黑碳气溶胶直接辐射效应的数值模拟研究 总被引：1，自引：1，他引：0
利用意大利国际理论物理研究中心（ICTP）提供的2000年各月气溶胶资料（包括人类活动和生物质燃烧所产生的气溶胶）,使用并行版本区域气候模式RegCM3,研究了黑碳气溶胶对中国区域气候的影响。结果表明,引入黑碳气溶胶后,冬、夏季中国大部分地区大气顶出现了正辐射强迫,其分布与垂直负荷分布基本相似。在仅考虑黑碳气溶胶的直接辐射效应时,中国大部分地区冬、夏季地面气温呈下降趋势,降温的高值区均位于中国东南部,冬季最大降温幅度约为0．9℃,夏季最大降幅约为2．4℃,夏季降温幅度明显大于冬季。相对于温度变化,黑碳气溶胶引起的降水变化较为复杂,无论是冬季还是夏季,降水量减小的区域均大于增加区。冬季降水量最大减幅约为20mm,夏季降水量最大减幅超过100mm,夏季降水量减幅明显大于冬季。冬、夏季仅西北和华南部分地区降水量有所增加。冬季中国大部分地区痕量降水和弱降水日数呈增加趋势;夏季黄河以北中国北方地区痕量降水和弱降水日数也是以增加为主。 相似文献
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利用饶平1961—2010年气温资料,通过线性拟合、M-K突变分析、小波分析等方法,对饶平近50年气温变化进行特征分析。结果表明：近50年饶平气温显著上升,增温速率为0.017 6℃/年,在1995年发生增温性突变,突变前后平均上升0.7℃。近50年秋冬季增温速率明显大于春夏季;冬季在20世纪80年代末发生突变,其他季节都在20世纪90年代发生突变;秋冬季突变前后增温大于春夏季。气候变暖对饶平极端气温及高温（低温）日数的影响：高温日数在1994年发生增加性突变,近50年来呈显著增加趋势,其中进入21世纪以来高温日数明显增多;低温日数在1983年发生减少性突变,极端最低气温呈显著上升趋势。小波分析得出饶平年平均气温在不同时段存在准6、13、20、28年年际变化周期。 相似文献
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选用1958—2009年聊城市3个国家气象站逐月极端最高气温和极端最低气温资料,采用累积距平、趋势系数方法,分析了聊城地区极端最高、最低气温变化的特征,得出：52a来聊城年极端最高气温变化趋势分为一个升温阶段和一个降温阶段,总体呈下降趋势,趋势系数为-0.3383。年极端最低气温变化趋势分为3个降温阶段和2个升温阶段,总体呈上升趋势,趋势系数为0.1849。极值年较差在减小;各季极端最高、极端最低气温呈非对称性变化。秋季各地极端最高气温增温幅度超过极端最低气温。春、夏、冬季极端最低气温增温而极端最高气温降温,且该特点在夏季表现得更突出;月极端气温变化范围在减小,极端温度变化趋于缓和,特别是进入21世纪,月极端最低和最高气温较20世纪90年代平均分别上升了1.6℃,1.1℃。 相似文献
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D. W. Sanders 《Climatic change》1986,9(1-2):187-194
Under natural conditions, balanced ecological systems develop in which the soil is protected by a cover of different plants. When man modifies the environment, in his attempts to produce more food, fiber and fuel, the ecological system is changed.This often results in the soil being exposed to the processes of accelerated water erosion. In this way, millions of hectares of land, particularly in the semi arid areas are now eroding.This paper stresses that the most important principle in controlling water erosion is to develop a new balanced system which is not only productive but which is also stable.Water erosion control schemes should therefore be based on the selection and introduction of correct land use.Examples are given of the types of measures that may be needed for cultivated, grazing and forestry lands.In some cases, a change in land use may also have to be supported by the construction of physical conservation measures. Some common examples of such measures are briefly described. 相似文献
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区域水资源配置中供水预测计算方法研究 总被引：1，自引：1，他引：0
供水预测是区域水资源配置中的重要组成部分,供水预测结果直接决定着水资源配置结果。由于常规的预测方法不能适应区域的实际情况,因此在考虑水质和水权条件下,定义了可供水量概念,并结合区域实际情况,提出以可供水量预测为基础的供水预测的实际计算步骤和方法及遇到实际问题的解决方法。由该方法对新郑市供水进行预测,预测结果符合实际,可为新郑市水资源配置及水系规划提供参考依据。 相似文献
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This paper explores the sensitivity of the benefits of alternative water allocation schemes and of project evaluation to global warming. If global warming shifts the mean of annual water supplies, there could be large impacts on the expected values of alternative water allocation schemes. The first section of the paper explores how well alternative schemes (such as market mechanisms, prior rights, or percentage flows) perform if the distribution of flows changes. In a case study of the Colorado River, market mechanisms and flow guarantees result in smaller impacts than rules which allocate inefficient percentages of flows to heterogeneous users. The second part of the paper explores the effect of a gradually changing distribution of flows on project evaluations. Project evaluation is sensitive to predicted future changes in mean flows. Project evaluation is not sensitive to changes in the variance of future flows unless the variance increase is large and the benefit measure is highly curvilinear. Because basin-specific changes in runoff from global warming are currently uncertain and much delayed, most project analyses will be unaffected by global warming. The most important response by water managers to climate change may simply be to closely monitor runoff and incorporate flexible rules in order to adapt their behavior to observed changes. 相似文献
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利用欧洲数值预报中心(ECMWF)发布的第一代全球分辨率ERA-Interim再分析数据,分析了1979～2014年天山山区水汽含量和云水含量的空间分布特征。结果显示：(1)水汽含量的高值中心出现在伊犁河谷地区,中心值域在10—11kg m-2之间,低值区位于天山中部的巴音布鲁克附近,中心值域在5—6kg m-2之间;夏季水汽含量最丰富,在8—11kg m-2之间。(2)云液水含量的高值区出现在博格达山北坡,而云冰水含量的高值区在西天山海拔较高的托木尔峰地区,低值区均在伊犁河谷等海拔低的地区;夏季云液水含量、云冰水含量均呈减少趋势,云冰水含量较云液水减少的更为明显,下降速率为0.28kg kg-1/10a;(3)垂直分布上,云液水含量在600hpa左右的高空出现高值区,中心最大值为10kg kg-1;云冰水含量的高值区则出现在500hpa左右的高空,为11kg kg-1;在对流层大气中云冰水含量值远大于云液水,且云冰水发展的高度较云液水更高。 相似文献
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Island wakes in shallow water are investigated using the Regional Ocean Modeling System (ROMS). In contrast to deep water where bottom stress can be neglected in island wakes, shallow water implies that inhomogeneity in the bottom stress plays an important role in the wake vorticity generation. A series of numerical experiments are conducted to investigate wake formation and evolution in shallow water. It is found that the vertical structures of shallow-water and deep-water wakes are significantly different because of the presence of a density frontal jet, which results from the interaction between stratification and bottom topography. The frontal jet reaches its maximum within the bottom boundary layer over the shelf, giving rise to vorticity. The potential vorticity (PV) balance analysis reveals that frictional and diapycnal processes play different roles in the PV anomalies. With the absence of lateral stress (i.e., a sea mountain case), the surface vorticity becomes much weaker than that in the presence of an island. 相似文献
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利用23.8GHz和31.65GHz双频地基微波辐射计观测资料,结合卫星云图、雷达、探空和自记雨量计等资料分析了2005年4月在河南新乡观测的不同云系影响时大气垂直积分含水量(V)和云中液态含水量(L)的演变特征,对4月8日低槽云系影响时V、L的特征进行了分析。结果表明:双频辐射计对空中水汽和液态水反映灵敏,不同天气背景时对应有不同的V、L值分布。云液水含量L的变化与云量的增减有关。降水开始之前,水汽含量V值有明显波动,液态水含量L值也有明显增加,一般增大到0.4mm时即出现降水。这些现象对降水开始有指示意义,可预测云系正处于降水产生的阶段,可应用于人工增雨作业。此外,根据微波辐射计观测资料分析了大气水汽、云液水和地面降水之间的定量关系,云中液态水仅占汽态水的8.7‰左右,落回地面的降水占空中水汽量的18%左右。 相似文献
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This article reviews the recent developments in the functional chain from climate models to climate scenarios, through hydrology all the way to water resources management, design and policy making. Although climate models, such as Global Circulation Models (GCMs) continue to evolve, their outputs remain crude and often even inappropriate to watershed-scale hydrological analyses. The bridging techniques are evolving, though. Many families of regionalization technologies are under progress in parallel. Perhaps the most important advances are in the field of regional weather patterns, such as ENSO (El Niño-Southern Oscillation), NAO (North Atlantic Oscillation) and many more. The gap from hydrology to water resources development is by far not that wide. The traditional and contemporary practices are well in place. In climate change studies, the bottleneck is not in this link itself but in the climatic input. The tendency seems to be towards integrated water resources assessments, where climate is only one among many changes that are expected to occur, such as demography, land cover and land use, economy, technologies, and so forth. In such a pragmatic setting a risk–analytic interpretation of those scenarios is often called for. The above-outlined continuum from climate to water is a topic where the physically based modelers, the empiricists and the pragmatists should not get restricted to their own way of thinking. The issues should develop hand in hand. Perhaps the greatest challenge is to incorporate and respect the pragmatic policy-related component to the two other branches. For this purpose, it is helpful to reverse the direction of thinking from time to time to start—instead of climate models—from practical needs and think how the climate scenarios and models help really in the difficult task of designing better water structures, outline better policies and formulate better operational rules in the water field. 相似文献
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John J. Boland 《Climatic change》1997,37(1):157-176
There has been substantial analysis of the possible impact of climate change on water supply, especially with respect to runoff and river flows. Less attention has been given to urban water use. Little is known of the suitability of various water use forecasting models for predicting climate impacts or of the best procedures for assessing this issue. This paper will: (1) demonstrate the feasibility of a scenario approach to describing possible changes in climate, (2) evaluate the IWR-MAIN model as a source of plausible water use forecasts given uncertain future climate, (3) test the effectiveness of conservation and pricing interventions in reversing the postulated effects of climate change, and (4) assess the significance of climate change for future urban water management. Other possible responses to climate change, such as supply augmentation, are not explicitly considered. Using data for the Washington (DC) metropolitan area, the study reveals problems with IWR-MAIN version 5.1 when used for this purpose, but results in a reasonable assessment of the possible water use consequences of climate change. Variation in future water use due to climate uncertainty was found to be moderate compared to other uncertain influences, and well within reach of feasible policy interventions. 相似文献