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921.
2021年“21·7”河南特大暴雨打破我国大陆小时气象观测纪录,该极端天气事件位列2021年中国十大天气气候事件第2位。已有研究使用气象地面站雨量观测资料对此次过程进行雨情分析和极值统计,但降水时空分布不均匀,单一来源资料存在不确定性。通过对比气象站和水文站雨量资料,分析两套业务观测系统记录“21·7”河南特大暴雨过程的异同,发现气象站和水文站雨量在时间和空间分布上具有很好的一致性,两者不同等级的累积降雨落区、逐日和逐时降雨演变趋势均一致性强,但累积雨量和雨强极值的空间分布和数值存在差异,两套资料在暴雨中心(过程雨量大于600 mm)的系统性偏差小于1%。气象站和水文站的融合资料呈现比单一资料更细致的降雨分布、更全面的演变特征。此外,基于融合资料发现累积雨量排名前3位的城市(郑州、鹤壁、新乡)均具有累积雨量大、小时雨强极强、强降雨集中、雨强突然增长的特征,鹤壁和新乡最强降雨时段分别比郑州晚26 h和28 h。 相似文献
922.
923.
基于卫星遥感数据和气象数据,采用距平分析、趋势分析、相关性分析等方法,分析了2000—2021年江西省植被生态质量时空变化特征,及其与气温、降水、日照等气候因子的关系。结果表明:1) 自2000年以来江西省植被生态质量整体改善明显,植被净初级生产力和生态质量指数呈明显上升趋势,年平均分别增加3.92 gC/m2和0.4,尤其2011年以后植被净初级生产力和生态质量指数处于较高水平,其中2018年最佳。2) 江西省植被生态指标低值区域位于城区周边,以及由长江和江西五大河流域的泥沙沉积形成的、以鄱阳湖为中心的冲积平原,中值区域位于中南部丘陵,高值区域分布于省境边陲山脉。3) 江西省植被生态指标与年降水量、年平均气温呈显著相关关系,与日照时数相关性不显著。与气候因子的相关性呈现地域差异,南部区域受气温影响较为明显,而中部盆地和东北区域受降水量影响更为明显。 相似文献
924.
思茅境内澜沧江径流变化量与云南气候变化的关系 总被引:2,自引:1,他引:2
以思茅澜沧江流域下游思茅境内水文站1960年1月~2001年12月的逐月径流量和云南的月雨量(气温)场格点资料为基础,用相关分析的方法,研究了思茅境内澜沧江流域的东西部径流量变化及其与云南气候变化的关系。结论为:思茅境内澜沧江下游流域的径流量变化与滇西南的降水量变化有显著的相关关系,其季节特征为春夏季较好,秋冬季次之;与元江河谷一带的气温变化也有显著的反相关关系,其中西部流域还与滇南的气温变化有显著的相关关系,其季节特征则为冬春季较好,夏秋季不显著。20世纪80年代以来,该流域的气温变化呈上升趋势,且西部升温的上升趋势更显著,气温上升对径流量的变化起减小的作用;20世纪90年代以来,该流域的东西部降水量变化出现了显著的差异,其东部的降水量明显增多,与此相一致,其东部径流量变化的增幅也明显大于其西部。 相似文献
925.
2004年我国天气气候特点 总被引:1,自引:0,他引:1
2004年,全国平均年降水量较常年偏少,且时空分布不均。春李至初夏,东北西部、内蒙古东部地区出现近50年来最严重的干旱;秋季,华南、长江中下游地区发生大范围的严重干旱。汛期,我国大江大河未发生大的流域性洪涝灾害,但局地性强降雨造成的暴雨洪涝和滑坡、泥石流等灾害比较频繁,四川、重庆、云南、河南、湖北、湖南等省市损失较重。全国年平均气温较常年明显偏高,但阶段性起伏变化较大,冬、春、秋季部分地区遭受低温冻害或雪灾,夏季南方出现持续高温天气。年内,有8个台风(热带风暴)登陆我国,其中台风“云娜”给浙江造成严重损失。雷雨大风、冰雹、雷击等局地强对流天气发生频繁。春季北方沙尘天气较上年同期增多。综合分析,2004年我国气候总体正常,气象灾害偏轻,属于偏好年景。 相似文献
926.
CHARACTERISTICS OF ENVIRONMENTAL AND CLIMATE CHANGE IN CHANGJIANG DELTA AND ITS POSSIBLE MECHANISM* 下载免费PDF全文
Characteristics of climate change in the Changjiang Delta were analyzed based on the annual mean meteorological data since 1961,including air temperature,maximum and minimum air temperature,precipitation,sunshine duration and visibility at 48 stations in that area(southern Jiangsu and northern Zhejiang),and its adjacent areas(northern Jiangsu,eastern Anhui and southern Zhejiang),together with the environmental data.The results indicate that it is getting warmer in the Changjiang Delta and cooler in adjacent areas,thus the Changjiang Delta becomes a big heat island,containing many little heat islands consisting of central cities,in which Shanghai City is the strongest heat island.The intensity of heat islands enhances as economic development goes up.From the year 1978.the beginning year of reform and opening policy,to the year 1997,the intensity of big heat island of Changjiang Delta has increased 0.5℃ and Shanghai heat island increased 0.8℃.However.since 1978 the constituents of SO2,NOx and TSP(total suspended particles)in the atmosphere,no matter whether in the Changjiang Delta or in the adjacent areas,have all increased,but pH values of precipitation decreased.In the meantime,both sunshine duration and visibility are also decreased,indicating that there exists a mechanism for climate cooling in these areas.Our analyses show that the mechanism for climate warming in the Changjiang Delta may be associated with heating increase caused by,economic development and increasing energy consumption.It is estimated that up to 1997 the intensity of warming caused by this mechanism in the Changjiang Delta has reached 0.8-0.9℃,about 4-4.5 times as large as the mean values before 1978.Since then,the increase rate has become 0. 035℃/a for the Changjiang Delta.It has reached 1.3℃ for Shanghai in 1997,about 12-13 times as large as the mean values before 1978.This is a rough estimation of increasing energy consumption rate caused by economic development. 相似文献
927.
闫敬华 《热带气象学报(英文版)》2000,6(2):162-171
In this paper, a newly established "South China Regional Short Range Climate Prediction Model System" is introduced and its performance is analyzed in real case simulation. It shows that the system has a good performance and suitable for short range climate modeling. The model simulates well the monthly mean, pentad mean and daily field, pentad mean and daily field and can depict more details than coarse resolution analyses. Weather systems and information can pass into and out of the model domain through lateral boundaries without notable damping. Almost all of the weather and climate changes can be reflected in the simulation, in which both the changing tendencies, amplitudes, speeds, and phases are consistent with the real cases. The simulated precipitation is much close to the observed one, both in the extent, position and in the intensity of rainfall. In addition, some smaller precipitation centers could also be reflected in the simulation. 相似文献
928.
Numerical simulations of anomalies of precipitation and surface air temperature in china in the summer of 1997 总被引:1,自引:0,他引:1
1.IntroductionStatisticalstudiesdemonstratedthatinEINinoyearstheprecipitationinsummerintheChangjiangRiverandHuaiheRiverBasinsisprobablyabovethenormalwhileitispossiblybelowthenormalinthenorthernChinaandtheHetao(theGreatBendoftheHuangheRiver)region.ThetemperatureinsummerisusuallylowerthannormalinEastAsia,especiallyinNortheastChina.Therewere6yearswithseverelowtemperaturesince1951,andtheyare1954,1957,1964,1972,1976and1983,whichareallrelatedtotheEINinoyears(seeHuangetal.,1989,1992;Xiangand… 相似文献
929.
国际技术协议通过促进技术的转让与升级,在发展中解决气候变化问题,因此受到越来越多的关注。根据"巴厘路线图"中的重要议题,在对国际技术协议进行简要介绍的基础上,评价了国际技术协议内在的价值与局限性。最后对国际技术协议的前景进行了展望,指出国际技术协议应当着眼于通过促进环境友好的先进技术由发达国家向发展中国家的转让,推动在应对气候变化领域内更深层次的南北合作,实现发展中国家的可持续发展,逐步解决气候变化问题。同时,为中国如何参与国际技术协议给出了建议。 相似文献
930.
The Stern Review on the Economics of Climate Change concluded that there can be “no doubt” the economic risks of business-as-usual (BAU) climate change are “very severe” [Stern, 2006. The Economics of Climate Change. HM Treasury, London, p. 188]. The total cost of climate change was estimated to be equivalent to a one-off, permanent 5–20% loss in global mean per-capita consumption today. And the marginal damage cost of a tonne of carbon emitted today was estimated to be around $312 [p. 344]. Both of these estimates are higher than most reported in the previous literature. Subsequently, a number of critiques have appeared, arguing that discounting is the principal explanation for this discrepancy. Discounting is important, but in this paper we emphasise that how one approaches the economics of risk and uncertainty, and how one attempts to model the very closely related issue of low-probability/high-damage scenarios (which we connect to the recent discussion of ‘dangerous’ climate change), can matter just as much. We demonstrate these arguments empirically, using the same models applied in the Stern Review. Together, the issues of risk and uncertainty on the one hand, and ‘dangerous’ climate change on the other, raise very strongly questions about the limits of a welfare-economic approach, where the loss of natural capital might be irreversible and impossible to compensate. Thus we also critically reflect on the state-of-the-art in integrated assessment modelling. There will always be an imperative to carry out integrated assessment modelling, bringing together scientific ‘fact’ and value judgement systematically. But we agree with those cautioning against a literal interpretation of current estimates. Ironically, the Stern Review is one of those voices. A fixation with cost-benefit analysis misses the point that arguments for stabilisation should, and are, built on broader foundations. 相似文献