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1.
宁夏植被覆盖动态变化及与气候因子的关系   总被引:5,自引:1,他引:4  
杜灵通  田庆久 《中国沙漠》2012,32(5):1479-1485
利用1999-2009年的SPOT-VGT NDVI数据,计算出宁夏近11 a来的植被覆盖度,对其变化特征进行了研究,结合同期气象观测资料,从空间上分析了植被覆盖度与区域气候因子之间的关系。结果表明,南部六盘山区和北部引黄灌区植被覆盖度高,而中部干旱带等地区的植被覆盖度较低,但中部干旱带却有较高的绝对变化率;从时间变化来看,近11 a来宁夏大部分地区的植被覆盖度在逐年增加。植被覆盖度的变化与气候因子有关,除引黄灌区和六盘山林区外,中部干旱带等地的植被覆盖度与降水呈正相关,区域气候的干湿波动,影响了植被覆盖度的高低;在有灌溉保障条件的农业垦殖区,植被覆盖度还与气温呈正相关,即有效积温的增加,会促进农作物生长,从而导致区域植被的覆盖度提高。  相似文献   

2.
长江三角洲城市带扩展对区域温度变化的影响   总被引:24,自引:1,他引:23  
利用DMSP/OLS 夜间灯光数据、土地利用统计数据和气象站常规观测资料, 结合NOAA/AVHRR、MODIS 反演的月地表温度数据, 定量考察了长江三角洲城市群热岛增温效应对区域温度气候趋势的贡献, 结果表明: ① 1992-2003 年长江三角洲城市化经历了一个快速的空间扩展过程, 宁镇扬、苏锡常、上海大城市区、杭州湾4 个城市群构成了一个“之” 字形城市带, 城市群之间出现城市化连片趋势, 城市带区域内1961-2005 年年平均气温增温 速率为0.28~0.44 oC/10a, 显著高于非城市带区域。② 城市热岛效应对区域平均温度的影响以夏秋季最强, 春季次之, 冬季最弱。③ 长江三角洲城市带热岛强度和城市总人口对数呈线性正相关关系。④ 城市带增温效应使得区域的年平均气温在1961-2005 年间增加了0.072 oC, 其中1991-2005 年间增温幅度为0.047 oC; 年最高气温升高了0.162 oC, 其中1991-2005 年间 增温幅度为0.083 oC, 表明1991-2005 年间长江三角洲城市带的空间扩展正在改变区域温度变化趋势, 且这种增温趋势显著。  相似文献   

3.
Based on non-radiance-calibrated DMSP/OLS nighttime light imagery from 1992 to 2003, urban land area statistical data, meteorological data and land surface temperature data retrieved by MODIS and NOAA/AVHRR data, the influence of urbanization on regional cli-matic trend of temperature in the Yangtze River Delta (YRD) was analyzed. Conclusions are as follows: 1) There is a significant urbanization process from 1992 to 2003 in the YRD. Four city clusters of Nanjing–Zhenjiang–Yangzhou, Suzhou–Wuxi–Changzhou, Shanghai and Hangzhou Bay form a zigzag city belt. The increase rate of annual mean air temperature in city-belt is 0.28–0.44℃/10a from 1991 to 2005, which is far larger than that of non-city-belt. 2) The urban heat island (UHI) effect on regional mean air temperature in different seasons is summer>autumn>spring>winter. 3) The UHI intensity and the urban total population logarithm are creditably correlated. 4) The UHI effect made the regional annual mean air temperature increased 0.072℃ from 1961 to 2005, of which 0.047℃ from 1991 to 2005, and the annual maximum air temperature increased 0.162℃, of which 0.083℃ from 1991 to 2005. All these indicating that the urban expansion in the YRD from 1991 to 2005 may be regarded as a serious climate signal.  相似文献   

4.
长江三角洲气温变化特征及城市化影响   总被引:16,自引:3,他引:13  
基于长江三角洲国家基本/基准站历史气象资料和区域人口资料,分析了1959~2005年和1981~2005年期间长江三角洲气温的年和季节变化特征,气温变化在大城市、中等城市和小城镇站之间的差异,以及城市化效应对气温的增温率和增温贡献率。结果表明,过去47年和25年期间,长江三角洲年均气温、年均最高和最低气温都显著增加,增温率都是冬季和春季较高,夏季最低。大城市站增温率明显高于小城镇和中等城市站,城市化效应对大城市气温基本上都是增温作用,其中对平均最低气温的增温率及贡献率最大,对平均最高气温都最小。长江三角洲气温变化趋势和增温率、城市化效应的增温率及增温贡献率与其他地区具有较好的一致性。  相似文献   

5.
Annual freezing and thawing index of 7 meteorological stations along the Qing- hai-Xizang Railway were calculated based on daily maximum and minimum temperature records for 1966-2004. Trends of annual freezing and thawing index were analyzed using the Mann-Kendall test and a simple linear regression method. The results show that: 1) The mean annual freezing indices range from 95 to 2300℃·d and the mean annual thawing indices range from 630 to 3250℃·d. The mean annual freezing index of the 7 stations exhibited decreasing trends with decreasing rate of -16.6- -59.1 ℃·d/10a. The mean annual thawing index of these 7 stations showed increasing trends with the related decreasing rate is 19.83-45.6℃·d/10a. 2) The MK trend test indicated the significant decreasing trends (significant at 〈 0.05 significant level) in the annual freezing index for most stations except for Golmud. The significant increasing trends can be observed in the annual thawing index for 4 stations except Golmud and Tuotuohe. Golmud was the only station with no trends in both annual freezing and annual thawing index.  相似文献   

6.
近50年新疆天山奎屯河流域冰川变化及其对水资源的影响   总被引:5,自引:0,他引:5  
张慧  李忠勤  牟建新  何海迪 《地理科学》2017,37(11):1771-1777
基于地形图、遥感影像、气象与水文资料,对气候变化背景下奎屯河流域近50 a冰川变化及其对水资源的影响进行了研究。结果表明:1964~2015年该流域冰川面积减小了约65.4 km2,冰储量亏损了约4.39 km3,且2000年后冰川消融与退缩加快。消融期内正积温增大带来的冰川物质支出(消融)高于源自年内降水的冰川物质收入(积累)是造成该流域冰川消融与退缩的主要原因。1964~2010年该流域径流年际变化总体呈上升趋势,1993年后径流增加趋势显著,且周期性丰枯变化发生了改变。52 a间该流域冰储量亏损引发的水资源损失量达39.5×108m3,年均亏损量约占多年平均径流量的12%,且20世纪80年代后冰川融水在径流中所占比重增大。  相似文献   

7.
全球平均气温未来情景的降尺度分析   总被引:2,自引:0,他引:2  
如何提高全球气候模拟数据的分辨率,以满足全球、区域乃至局地陆地生态系统全球变化响应的定量分析,是当今全球气候变化研究的核心内容之一。在全球尺度上,本文利用全球气象观测站点的气候数据和DEM 数据,对全球年平均气温与纬度和海拔高程之间相关性进行回归分析,建立全球气候降尺度空间模拟的统计转移函数,并与高精度曲面建模(HASM)方法进行集成,从而实现IPCC GCM HadCM3 的模拟数据从3.75° × 2.5°到 0.125° × 0.125°的降尺度处理。研究结果表明,在3 种气候情景的T1-T4 时段内,格陵兰岛平均气温在0℃以下的区域和南极洲平均气温在-35℃以下的区域均呈逐渐缩减趋势,赤道至南北回归线之间的平均气温大于40℃以上的区域呈逐渐增加趋势。其中,A1Fi 情景的平均气温上升速度最快,A2 情景次之,B2 情景的平均气温上升速度最慢。构建降尺度方法有效地将IPCC GCMs的粗分辨率的气候情景数据降尺度转换成高分辨率的气候数据,并克服和弥补了目前IPCC GCMs的模拟数据因分辨率低而不能对区域乃至局地气候变化的细节及趋势进行刻画的缺陷。  相似文献   

8.
张静  吴洁  秦公伟  冯俊霄  郑博  赵文博 《地理科学》2020,40(10):1742-1752
运用GIS空间分析,研究了秦巴山区1960—2015年地表太阳辐射的时空动态。结果表明:① 秦巴山区地表太阳辐射量年平均值为4 482.77 MJ/m2,呈现由南向东北、西北递增的态势;年际变异系数为8.85%,呈现由西南向东北递减的态势。② 地表太阳辐射量年际变化呈明显下降趋势,年平均递减率为?10.17 MJ/m2,1970—1992年下降尤为明显;空间上呈现西北局部不显著的微增和东部普遍显著性的减少。③ 年内地表太阳辐射量呈单峰型,最大值在7月,最小值在12月,空间上由南向西北、东北递增;7月年递减率为?0.49 MJ/m2,以西南剑阁县、北川县和东南保康县递减明显;12月年递减率为?0.715 MJ/m2,以汉滨区递减最快;④ 结合降水量和≥10℃积温,将秦巴山区分为5个农业气候区。秦巴山区地表太阳辐射量呈“北高南低的纬向变化,高纬东西分异”,年内递减区表现为“夏季纬向变化,冬季涡旋状”的空间差异。因此,区域内部地表太阳辐射量空间差异大,利用光能资源助力农业扶贫,应体现区域差异。  相似文献   

9.
根据腾格里沙漠周边地区9个气象站点1960-2012年逐月平均气温、平均最高气温、平均最低气温、降水量、平均相对湿度、日照时数和平均风速的观测资料,利用线性回归、滑动平均和Mann-Kendall突变检验分析了该区1960-2012年气候变化特征。结果表明:1960-2012年,腾格里沙漠周边地区年平均气温以0.34 ℃/10a的速率呈显著上升的趋势,并于1989年发生显著突变;从季节变化来看,冬季升温幅度最大,达0.52 ℃/10a;年平均最高、最低气温均呈显著上升的趋势,但是年平均最低气温的升温速率0.44 ℃/10a明显大于最高气温升温速率0.25 ℃/10a,增暖的不对称性导致年平均气温日较差以0.18 ℃/10a的速率显著减小。年降水量以1.08 mm/10a的速率增加,但变化趋势不显著,四季降水量均有不同程度的增加;湿润指数的变化亦不显著,年、春季、夏季和秋季湿润指数均有减小趋势,冬季湿润指数有增加趋势;年、季平均风速皆呈显著减小的趋势,年平均风速减小的速率为0.15 m·s-1·(10a)-1,日照时数以5.6 h/10a的速率呈不显著的增加趋势,各季节日照时数有不同的变化趋势,春季和夏季日照时数呈增加趋势,而秋季和冬季的日照时数呈减小趋势。  相似文献   

10.
王景才  郭佳香  徐蛟  李帆 《地理科学》2017,37(4):611-619
选取1960~2014年淮河上中游流域19个气象站点的月降水量、气温和日照时数等数据,采用气候倾向率、Mann-Kendall、Morlet小波和相关系数法,对流域年和四季降水、气温和日照时数的变化趋势、多时间尺度演变特征以及相关性进行了研究。结果表明:① 降水在年和四季线性变化趋势不显著;气温除夏季不显著外,年和春、秋、冬季变暖趋势显著;日照时数除春季不显著外,年和夏、秋、冬季节变短趋势显著;② 降水、气温、日照时数在年和四季分别表现出多个时间尺度的相对丰枯、冷暖和长短交替特征;第一主周期尺度及其相应的平均变化周期在年和四季有的较接近有的相差较大,第一主要平均周期介于2~10 a之间;③ 气温的复相关系数均小于降水和日照时数;除冬季气温复相关系数较小外,其他季节各要素均较大。降水-日照的偏相关系数绝对值在年和四季均最大。降水-日照时数、降水-气温大部分情况呈反相关系,冬季气温和日照时数在主周期尺度28 a下呈同相变化。  相似文献   

11.
The spatial distribution patterns of climatic changes in Yakutia are considered. For 26 meteorological stations of Yakutia we calculated the linear trend coefficients of climatic characteristics: air temperature (mean annual, January and July temperatures) and the mean annual amount of atmospheric precipitation from 1966 to 2016. Maps of climate change trends were compiled from linear trend coefficients. A spatial analysis of the zonal (regional) peculiarities of the climate of Yakutia has been carried out. An increase in air temperature was established for the 50-year period under consideration. It was found that the annual values of the air temperature trend are positive and, on average, a characteristic trend change interval is 0.3 to 0.6 °C/10 yr. Most of the meteorological stations recorded trends of air temperature with maximum values in winter and minimum values in summer. It was determined that the values of the trends in annual precipitation show different directions, and positive trends occur on more than 70% of the territory of Yakutia. Their maximum corresponds to the mountain-taiga regions of Southern Yakutia. Negative trends in precipitation with values of up to–15 mm/10 yr. are observed in tundra landscapes. The findings show that different regions of Yakutia respond differently to climate change. The trend of an increase in mean annual temperature is largely due to the rise in temperatures during the winter months. The rise in air temperature in Yakutia may be part of global warming. Over the last 50 years there has been an increase in the amount of precipitation in Yakutia as a whole.  相似文献   

12.
长江三角洲城市带扩展对区域温度变化的影响   总被引:7,自引:0,他引:7  
Based on non-radiance-calibrated DMSP/OLS nighttime light imagery from 1992 to 2003, urban land area statistical data, meteorological data and land surface temperature data retrieved by MODIS and NOAA/AVHRR data, the influence of urbanization on regional cli- matic trend of temperature in the Yangtze River Delta (YRD) was analyzed. Conclusions are as follows: 1) There is a significant urbanization process from 1992 to 2003 in the YRD. Four city clusters of Nanjing–Zhenjiang–Yangzhou, Suzhou–Wuxi–Changzhou, Shanghai and Hangzhou Bay form a zigzag city belt. The increase rate of annual mean air temperature in city-belt is 0.28–0.44℃/10a from 1991 to 2005, which is far larger than that of non-city-belt. 2) The urban heat island (UHI) effect on regional mean air temperature in different seasons is summer>autumn>spring>winter. 3) The UHI intensity and the urban total population logarithm are creditably correlated. 4) The UHI effect made the regional annual mean air temperature increased 0.072℃ from 1961 to 2005, of which 0.047℃ from 1991 to 2005, and the annual maximum air temperature increased 0.162℃, of which 0.083℃ from 1991 to 2005. All these indicating that the urban expansion in the YRD from 1991 to 2005 may be regarded as a serious climate signal.  相似文献   

13.
峡谷暖区农业地形气候垂直分层及其农业发展战略   总被引:8,自引:2,他引:6  
罗宏  杨志峰 《地理研究》1999,18(4):407-412
以鄂西南峡谷暖区为例,选取适当的农业地形气候垂直分层指标,运用主成分分析方法对峡谷暖区地形气候进行了垂直分层,以及利用层次分析法对各中垂直农业气候层的农业发展战略进行了决策分析,结果表明,峡谷暖区可划分为三个垂直农业气候层,即温热层、温暖层和温和层。且实行以种植为主,农、林、牧、副、渔并演的方针是峡谷暖区发展农业生产的重要战备措施。  相似文献   

14.
Annual freezing and thawing index of 7 meteorological stations along the Qing-hai-Xizang Railway were calculated based on daily maximum and minimum temperature records for 1966?2004. Trends of annual freezing and thawing index were analyzed using the Mann-Kendall test and a simple linear regression method. The results show that: 1) The mean annual freezing indices range from 95 to 2300℃·d and the mean annual thawing indi-ces range from 630 to 3250℃·d. The mean annual freezing index of the 7 stations exhibited decreasing trends with decreasing rate of ?16.6– ?59.1℃·d /10a. The mean annual thawing index of these 7 stations showed increasing trends with the related decreasing rate is 19.83–45.6℃·d /10a. 2) The MK trend test indicated the significant decreasing trends (sig-nificant at < 0.05 significant level) in the annual freezing index for most stations except for Golmud. The significant increasing trends can be observed in the annual thawing index for 4 stations except Golmud and Tuotuohe. Golmud was the only station with no trends in both annual freezing and annual thawing index.  相似文献   

15.
六盘山景观格局及与主要气候因子的关系   总被引:3,自引:1,他引:2  
以六盘山为研究区,根据野外植被调查资料、Landsat TM影像和气象数据,利用遥感影像分类方法、回归分析方法等,在研究区从南向北选取三条东西走向的等大、平行样区,系统研究景观格局与主要气候要素之间的关系。结果表明:六盘山地区年平均气温为0.8℃-7.0℃,主要受高程控制,气温直减率为0.51℃/100 m;降水量为599-770 mm,在水平方向上东南多、西北少;在垂直方向上,先随着海拔高度上升而增加,至最大降水高度(2502 m)后呈下降趋势。六盘山地区主要植被类型为暖温带落叶阔叶林,随着南至北降水量的逐步减少,植被类型有从森林经由灌丛草甸向草原过渡的趋势,北部草原成分逐渐增加。因此区域降水条件对西北干旱区的植被格局起到决定性作用。该结论有助于理解气候变化背景下生态系统的响应机理,可为区域生态建设提供理论依据。  相似文献   

16.
Based on the daily observation data of 824 meteorological stations during 1951- 2010 released by the National Meteorological Information Center, this paper evaluated the changes in the heat and moisture conditions of crop growth. An average value of ten years was used to analyze the spatio-temporal variation in the agricultural hydrothermal conditions within a 1 km2 grid. Next, the inter-annual changing trend was simulated by regression analysis of the agricultural hydrothermal conditions. The results showed that the contour lines for temperature and accumulated temperatures (the daily mean temperature ≥0°C) increased significantly in most parts of China, and that the temperature contour lines had all moved northwards over the past 60 years. At the same time, the annual precipitation showed a decreasing trend, though more than half of the meteorological stations did not pass the significance test. However, the mean temperatures in the hottest month and the coldest month exhibited a decreasing trend from 1951 to 2010. In addition, the 0°C contour line gradually moved from the Qinling Mountains and Huaihe River Basin to the Yellow River Basin. All these changes would have a significant impact on the distribution of crops and farming systems. Although the mechanisms influencing the interactive temperature and precipitation changes on crops were complex and hard to distinguish, the fact remained that these changes would directly cause corresponding changes in crop characteristics.  相似文献   

17.
In this study, the spatial distribution and changing trends of agricultural heat and precipitation resources in Northeast China were analyzed to explore the impacts of future climate changes on agroclimatic resources in the region. This research is based on the output meteorological data from the regional climate model system for Northeast China from 2005 to 2099, under low and high radiative forcing scenarios RCP4.5 (low emission scenario) and RCP8.5 (high emission scenario) as proposed in IPCC AR5. Model outputs under the baseline scenario, and RCP4.5 and RCP8.5 scenarios were assimilated with observed data from 91 meteorological stations in Northeast China from 1961 to 2010 to perform the analyses. The results indicate that: (1) The spatial distribution of temperature decreases from south to north, and the temperature is projected to increase in all regions, especially under a high emission scenario. The average annual temperature under the baseline scenario is 7.70°C, and the average annual temperatures under RCP4.5 and RCP8.5 are 9.67°C and 10.66°C, respectively. Other agricultural heat resources change in accordance with temperature changes. Specifically, the first day with temperatures ≥10°C arrives 3 to 4 d earlier, the first frost date is delayed by 2 to 6 d, and the duration of the growing season is lengthened by 4 to 10 d, and the accumulated temperature increases by 400 to 700°C·d. Water resources exhibit slight but not significant increases. (2) While the historical temperature increase rate is 0.35°C/10a, the rate of future temperature increase is the highest under the RCP8.5 scenario at 0.48°C/10a, compared to 0.19°C/10a under the RCP4.5 scenario. In the later part of this century, the trend of temperature increase is significantly faster under the RCP8.5 scenario than under the RCP4.5 scenario, with faster increases in the northern region. Other agricultural heat resources exhibit similar trends as temperature, but with different specific spatial distributions. Precipitation in the growing season generally shows an increasing but insignificant trend in the future, with relatively large yearly fluctuations. Precipitation in the eastern region is projected to increase, while a decrease is expected in the western region. The future climate in Northeast China will change towards higher temperature and humidity. The heat resource will increase globally, however its disparity with the change in precipitation may negatively affect agricultural activities.  相似文献   

18.
近50a来北方农牧交错带气温变化趋势及突变分析   总被引:12,自引:3,他引:9  
利用北方农牧交错带内及邻近的共46个气象站点1957—2007年的气温数据资料,运用Mann-Kendall非参数检验法、R/S分析法,对气温变化趋势及突变特征进行了分析。结果表明,近50a来北方农牧交错带年、季气温普遍升高,20世纪90年代以后气温上升趋势显著,达到了99%的信度水平,年平均气温增温速率约为0.32℃/10a,明显高于全国和全球的气温增长率,其中冬季增温尤为明显,对全年增温贡献率最大;Hurst指数分析表明,整个北方农牧交错带年、季气温在未来仍表现出上升趋势,冬季的增温持续性最强;北方农牧交错带年、季升温幅度在空间上表现出一定的区域差异性,其年平均气温在90年代初发生了升温突变。  相似文献   

19.
基于宁夏地区1978—2010年旱灾灾情要素年资料和23个气象站1971—2011年月平均气温和月降水量资料,运用Mann-Kendall趋势分析和突变检验方法,详细分析了该地区近33年旱灾灾情及近41年气候的时空变化特征,在此基础上,剖析了持续性旱灾产生的气候背景。结果表明:1978—2010年宁夏地区旱灾呈持续性加重趋势,受灾人口、农作物受灾面积和直接经济损失增速分别为28.78万人/10a、3.16万hm2/10a和8 504.04万元/10a。空间变化上,旱灾加重速度由中部向北、向南呈减慢趋势。1971—2011年宁夏地区气候总体呈暖干化趋势,年平均气温、平均最高气温和最低气温的升温率分别为0.42 ℃/10a、0.37 ℃/10a和0.50 ℃/10a,增暖表现为全年温度升高,年平均气温和平均最高气温于20世纪90年代早期发生了显著增暖突变;降水量呈减少趋势,但不显著。宁夏持续性旱灾是气温持续快速上升和降水量减少共同作用的结果,其中气温显著增高是该地区干旱灾害加剧的主要气候因素。  相似文献   

20.
南极长城站_1985_2008_和中山站_1989_2008_地面温度变化   总被引:2,自引:0,他引:2       下载免费PDF全文
利用长城站1985-2008年和中山站1989-2008年逐月气温资料,分析了两站短期气候特征及其变化趋势,评估了两站地面温度观测资料的代表性。结果表明,长城站和别林斯高晋站同期的年平均温度均为-2.1℃,温度趋势变化速率分别为0.27℃/10a.和0.33℃/10a,呈现出南极半岛具有明显的气候变暖趋势。中山站和戴维斯站的同期温度变化速率分别为0.12℃/10a.和0.07℃/10a,显示的气候变暖趋势不明显。两站温度变化趋势与邻近站相比基本相似,表明两站观测的温度资料具有南极乔治王岛和东南极沿岸区的代表性。长城站四季平均气温都呈上升趋势,且秋季增温速率最大,冬季次之,其它季节不明显。中山站春季和冬季具有降温趋势,秋季和夏季具有升温倾向,其中以秋季升温趋势和冬季降温趋势最为显著。  相似文献   

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