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1.
乌鲁木齐河流域参考作物蒸散量时空变化特征   总被引:5,自引:0,他引:5  
根据乌鲁木齐河流域5个气象站近30a的地面气象观测资料.应用1998年FAO最新推荐的Penman-Monteith公式计算了各月参考作物蒸散量ETo,在此基础上,分析了ETo的月际和年际变化特征,并探讨了各气候要素和海拔高度与ETo的相关关系。结果表明,乌鲁木齐河流域ETo空间变化较大。从山前冲洪积平原的人工绿洲区到高寒地带的乌鲁木齐河源头ETo多年平均值呈明显递减趋势,平均垂直递减率为17.3mm.(100m)-1;30a来,流域各站的年参考作物蒸散量ETo均呈递减趋势,递减速率为-0.05mm.a-1~-5.21mm.a-1;ETo与平均气温、平均最高气温、平均最低气温、空气相对湿度、风速、日照时数、降水量和小型蒸发皿蒸发量均具有较好的相关性;造成近30a乌鲁木齐河流域参考作物蒸散量呈递减趋势的气候原因是:气温、空气相对湿度升高和降水增多以及风速、日照时数减小等气候变化综合作用的结果。  相似文献   

2.
近30年安徽省地表干湿时空变化及对农业影响   总被引:5,自引:2,他引:5       下载免费PDF全文
采用FAO Penman-Monteith模型, 并利用安徽省辐射观测资料对其净辐射项进行修正, 计算近30年安徽省的参考作物蒸散量。用此计算值和相应时段的降水量计算干燥度 (Ia), 并进行了基于干燥度指标不同时间尺度的区域地表干湿状况变化分析。分析表明:1971—2000年安徽省年干燥度平均值Ia=1的等值线为湿润区和半湿润区的分界线, 该分界线与1000 mm的年雨量线有很好的一致性, 同时也具有清晰的农业意义。20世纪70—90年代Ia=1的等值线南北波动, 其波动区域正是安徽省江淮分水岭易旱区。在此基础上分析了半湿润区、波动区域和湿润区降水量、参考作物蒸散量和干燥度年代际、年际和半年际的变化趋势及变异率以及逐月干旱频率及其对农业的影响。  相似文献   

3.
参考作物蒸散模型对比分析及评价   总被引:1,自引:0,他引:1  
利用山东省6个气象台站45 a(1960-2004年)的逐日气象资料并选用7种参考作物蒸散模型,分别计算了上述各地的参考作物蒸散,对模型结果进行时空分布对比分析;进而以FAO推荐的Penman-Monteith模型为对照,利用最小一乘法对其余6种模型进行优化并对优化前后的模型进行时空比较.结果表明:Makkink模型在6个台站的时空分布模拟效果均最好,Mass-transfer模型在7-8月明显偏低,Net Radiation模型各站全年基本都偏高;根据不同月份的相对偏差情况,采用最小一乘法进行分月优化,优化后的模型预测月参考作物蒸散标准误差小于5 mm,平均相对误差小于8.5%,台站的年参考作物蒸散相对误差也基本小于10%,说明这些含参数较少的模型经优化后基本上可用,当资料缺损时不失为Penman-Monteith模型的替代模型.  相似文献   

4.
蒸散量是内陆水循环的重要环节,探索西北干旱半干旱区气候因素对蒸散量的影响,有助于深入研究内陆水循环对气候变化的响应。本文利用玛纳斯河流域1964—2010年6个气象台站的日气温、风速、相对湿度等气候资料,通过Penman-Monteith公式估算玛纳斯河流域的参考作物蒸散量(RET),利用回归分析、Mann-Kendall等方法分析研究参考作物蒸散量的时空变化特征。结果表明:(1)玛纳斯河流域参考作物蒸散量空间差异明显,除石河子外南部绿洲区参考作物蒸散量均大于北部绿洲边缘区,季节变化趋势也较北部明显。从季节上来看,玛纳斯河流域参考作物蒸散量季节变化差异显著,夏季是参考作物蒸散量变化的主要贡献者,其次是秋季大于春季,冬季的变化最小。(2)南部绿洲区平均风速的减小是参考作物蒸散量减少的主要原因,北部绿洲边缘区相对湿度的增加是参考作物蒸散量减少的主要原因。  相似文献   

5.
参考作物蒸散量的多种计算方法及其结果的比较   总被引:54,自引:3,他引:51       下载免费PDF全文
分别用 FAO Penman- Monteith公式 (模型 1 )、FAO Penman 修正式 (模型 2 )和国内Penman修正式 (模型 3)计算了泰安和西峰两地的参考作物蒸散量 ,对 3种方法的计算结果进行了比较 .模型 1得到的参考作物蒸散量大于后 2种模型 ,导致不同模型计算偏差的原因是 3种模型各自选用了不同的辐射项和动力项计算式 ,且计算偏差随季节和地理条件而变 .建议计算区域参考作物蒸散量用模型 1 ,计算单站逐日参考作物蒸散量 3种模型都可用 .  相似文献   

6.
北疆地区参考作物蒸散量时空变化特征   总被引:1,自引:0,他引:1  
为明确北疆地区在全球气候变暖背景下合理的灌溉制度,利用北疆地区22个气象站49 a(1962~2010年)的逐日气象资料,运用Penman-Monteith公式计算北疆地区1962~2010年的参考作物蒸散量ET0(reference crop evapotranspiration),并用Mann-Kendall方法对其进行突变检验,基于Arc GIS9.3空间分析功能模块对北疆参考作物蒸散量进行了空间变化分析。结果表明:研究区域的ET0在1983年发生向下突变,ET0在时间分布上整体呈下降趋势,主要受该地区相对湿度和风速的影响;ET0从北疆的东北部和西南部向中间逐渐升高,东南部和西部表现略高,具有明显的区域差异;4~10月ET0对全年ET0的分布具有显著影响。  相似文献   

7.
基于修正的Penman-Monteith(P-M)模型,利用1980~2020年黄河源区的气象台站观测数据和陆-气间水热交换观测试验数据,计算出该区域的陆面参考蒸散量,分析了黄河源区蒸散量的时空演变特征,探讨了影响黄河源区蒸散量变化的原因。结果表明:(1)修正的P-M模型能较准确地估算黄河源区的参考蒸散量,与实际观测的相关系数在0.85以上。(2)黄河源区的蒸散量总体呈上升趋势,但在20世纪80年代中期和90年代中期均呈显著减少趋势;近年来,中部和西部地区的蒸散量呈减少趋势,而东部地区的蒸散量呈增加趋势。(3)黄河源区年蒸散量呈自东向西减小的分布特征,东、中、西部地区分别为473.5~516.0mm、437.6~473.5mm和386.3~437.6mm;四季蒸散量差异明显,夏季最大,春季和秋季次之,冬季最小。(4)黄河源区蒸散量随温度、风速和日照时数的增加而增大,随相对湿度和降水量的增大而减小。   相似文献   

8.
根据南京地区粳稻、籼稻两个品种水稻分别在干旱、水层条件下的逐时、逐日蒸散量观测资料,采用Penman-Monteith模型(以下简称PM模型)对水稻蒸散量进行模拟,并对比模拟蒸散值与观测蒸散值。通过计算,对PM模型的可靠性进行验证。结果表明:(1)水层条件下PM模型的精度比干旱条件下高。(2)模拟值乘以作物系数后,与蒸散实际测量值更加接近。(3)通过敏感性分析可知,使用PM模型进行蒸散量模拟时,方程中各个因子取值的准确性对模拟结果的精确度有较大影响,计算时要合理确定各个因子值。(4)水层条件下稻田的蒸散量明显大于干旱条件下的蒸散量。  相似文献   

9.
几种蒸散计算方法在怀来地区的适用性研究   总被引:3,自引:0,他引:3  
王晓晨  朱忠礼  季辰  施生锦 《气象》2016,42(11):1395-1401
作物蒸散量即为植株蒸腾与棵间蒸发之和,准确地测定作物实际蒸散量,对研究农作物节水种植技术、加强水资源管理和制定合理的灌溉计划具有十分重要的意义。文章应用2013年生长季(5-10月)自动称重式蒸渗仪实测河北怀来地区夏玉米的蒸散量,从月、日两个时间尺度评价Penman-Monteith(FAO P-M)、Hargreaves、Priestley-Taylor三种基于参考作物蒸散量计算实际蒸散的方法在怀来地区的适用性,结果表明:(1)三种方法计算的夏玉米月、日实际蒸散相对于蒸渗仪实测结果均存在一定偏差,FAO P-M方法与Hargreaves方法表现较好,准确度相差不大,Priestley-Taylor方法准确性最差;(2)影响实际蒸散计算结果的主要气象因子为太阳净辐射和温度,Hargreaves方法计算结果在怀来地区可信度较高;(3)Hargreaves方法所需参数较少,在计算量方面占有很大的优势,在怀来地区适用性最好。  相似文献   

10.
参考作物蒸散量是表征气候干湿程度、植被耗水量、生产潜力及水资源供需平衡的重要指标之一。以海口和敦煌两个气候相差较大的站点为例,利用Irmark-Allen、Hargreaves、Jensen-Haise 3种基于温度的ET 0计算方法,计算了 2013 2015 年两个站点的参考作物蒸散量,以FAO98 Penman-Monteith方法计算所得结果为标准,依据相关系数(R)及其显著性(P)、均方根误差(RMSE)和平均偏差(MBE)等量化指标,分别对3种方法计算结果在两个站点月和日序列的适用性进行评价,并对这3种方法进行本地化修正优化和检验。结果表明:本地化前,Irmark-Allen方法在海口的计算与Penman-Monteith的偏差最小且相关性好( R =0.97, P <0.01,RMSE=0.38 mm/d,MBE=-0.01 mm/d),其他两种方法均高估。3种基于温度的ET 0方法在敦煌都有很大的误差,其中Irmark-Allen方法在夏季偏低,在冬季偏高;Hargreaves方法整体偏高;Jensen-Haise方法在冬季不适用,出现无效负值,而在其他时段偏高。本地化后,3种基于温度的ET 0方法在两个地区都得到明显改善,其中Jensen-Haise方法在海口效果最好( R =0.96, P< 0.01,RMSE=0.61 mm/d,MBE=0.003 mm/d),在敦煌效果也是最好的( R =0.96, P <0.01,RMSE=0.69 mm/d, MBE=-0.02 mm/d)。  相似文献   

11.
The spatial and temporal variations of daily maximum temperature(Tmax), daily minimum temperature(Tmin), daily maximum precipitation(Pmax) and daily maximum wind speed(WSmax) were examined in China using Mann-Kendall test and linear regression method. The results indicated that for China as a whole, Tmax, Tmin and Pmax had significant increasing trends at rates of 0.15℃ per decade, 0.45℃ per decade and 0.58 mm per decade,respectively, while WSmax had decreased significantly at 1.18 m·s~(-1) per decade during 1959—2014. In all regions of China, Tmin increased and WSmax decreased significantly. Spatially, Tmax increased significantly at most of the stations in South China(SC), northwestern North China(NC), northeastern Northeast China(NEC), eastern Northwest China(NWC) and eastern Southwest China(SWC), and the increasing trends were significant in NC, SC, NWC and SWC on the regional average. Tmin increased significantly at most of the stations in China, with notable increase in NEC, northern and southeastern NC and northwestern and eastern NWC. Pmax showed no significant trend at most of the stations in China, and on the regional average it decreased significantly in NC but increased in SC, NWC and the mid-lower Yangtze River valley(YR). WSmax decreased significantly at the vast majority of stations in China, with remarkable decrease in northern NC, northern and central YR, central and southern SC and in parts of central NEC and western NWC. With global climate change and rapidly economic development, China has become more vulnerable to climatic extremes and meteorological disasters, so more strategies of mitigation and/or adaptation of climatic extremes,such as environmentally-friendly and low-cost energy production systems and the enhancement of engineering defense measures are necessary for government and social publics.  相似文献   

12.
正While China’s Air Pollution Prevention and Control Action Plan on particulate matter since 2013 has reduced sulfate significantly, aerosol ammonium nitrate remains high in East China. As the high nitrate abundances are strongly linked with ammonia, reducing ammonia emissions is becoming increasingly important to improve the air quality of China. Although satellite data provide evidence of substantial increases in atmospheric ammonia concentrations over major agricultural regions, long-term surface observation of ammonia concentrations are sparse. In addition, there is still no consensus on  相似文献   

13.
Observed daily precipitation data from the National Meteorological Observatory in Hainan province and daily data from the National Centers for Environmental Prediction/National Center for Atmospheric Research (NCEP/NCAR) reanalysis-2 dataset from 1981 to 2014 are used to analyze the relationship between Hainan extreme heavy rainfall processes in autumn (referred to as EHRPs) and 10–30 d low-frequency circulation. Based on the key low-frequency signals and the NCEP Climate Forecast System Version 2 (CFSv2) model forecasting products, a dynamical-statistical method is established for the extended-range forecast of EHRPs. The results suggest that EHRPs have a close relationship with the 10–30 d low-frequency oscillation of 850 hPa zonal wind over Hainan Island and to its north, and that they basically occur during the trough phase of the low-frequency oscillation of zonal wind. The latitudinal propagation of the low-frequency wave train in the middle-high latitudes and the meridional propagation of the low-frequency wave train along the coast of East Asia contribute to the ‘north high (cold), south low (warm)’ pattern near Hainan Island, which results in the zonal wind over Hainan Island and to its north reaching its trough, consequently leading to EHRPs. Considering the link between low-frequency circulation and EHRPs, a low-frequency wave train index (LWTI) is defined and adopted to forecast EHRPs by using NCEP CFSv2 forecasting products. EHRPs are predicted to occur during peak phases of LWTI with value larger than 1 for three or more consecutive forecast days. Hindcast experiments for EHRPs in 2015–2016 indicate that EHRPs can be predicted 8–24 d in advance, with an average period of validity of 16.7 d.  相似文献   

14.
Based on the measurements obtained at 64 national meteorological stations in the Beijing–Tianjin–Hebei (BTH) region between 1970 and 2013, the potential evapotranspiration (ET0) in this region was estimated using the Penman–Monteith equation and its sensitivity to maximum temperature (Tmax), minimum temperature (Tmin), wind speed (Vw), net radiation (Rn) and water vapor pressure (Pwv) was analyzed, respectively. The results are shown as follows. (1) The climatic elements in the BTH region underwent significant changes in the study period. Vw and Rn decreased significantly, whereas Tmin, Tmax and Pwv increased considerably. (2) In the BTH region, ET0 also exhibited a significant decreasing trend, and the sensitivity of ET0 to the climatic elements exhibited seasonal characteristics. Of all the climatic elements, ET0 was most sensitive to Pwv in the fall and winter and Rn in the spring and summer. On the annual scale, ET0 was most sensitive to Pwv, followed by Rn, Vw, Tmax and Tmin. In addition, the sensitivity coefficient of ET0 with respect to Pwv had a negative value for all the areas, indicating that increases in Pwv can prevent ET0 from increasing. (3) The sensitivity of ET0 to Tmin and Tmax was significantly lower than its sensitivity to other climatic elements. However, increases in temperature can lead to changes in Pwv and Rn. The temperature should be considered the key intrinsic climatic element that has caused the "evaporation paradox" phenomenon in the BTH region.  相似文献   

15.
Storms that occur at the Bay of Bengal (BoB) are of a bimodal pattern, which is different from that of the other sea areas. By using the NCEP, SST and JTWC data, the causes of the bimodal pattern storm activity of the BoB are diagnosed and analyzed in this paper. The result shows that the seasonal variation of general atmosphere circulation in East Asia has a regulating and controlling impact on the BoB storm activity, and the “bimodal period” of the storm activity corresponds exactly to the seasonal conversion period of atmospheric circulation. The minor wind speed of shear spring and autumn contributed to the storm, which was a crucial factor for the generation and occurrence of the “bimodal pattern” storm activity in the BoB. The analysis on sea surface temperature (SST) shows that the SSTs of all the year around in the BoB area meet the conditions required for the generation of tropical cyclones (TCs). However, the SSTs in the central area of the bay are higher than that of the surrounding areas in spring and autumn, which facilitates the occurrence of a “two-peak” storm activity pattern. The genesis potential index (GPI) quantifies and reflects the environmental conditions for the generation of the BoB storms. For GPI, the intense low-level vortex disturbance in the troposphere and high-humidity atmosphere are the sufficient conditions for storms, while large maximum wind velocity of the ground vortex radius and small vertical wind shear are the necessary conditions of storms.  相似文献   

16.
正AIMS AND SCOPE Atmospheric and Oceanic Science Letters (AOSL) publishes short research letters on all disciplines of the atmosphere sciences and physical oceanography.  相似文献   

17.
《大气和海洋科学快报》2014,7(6):F0003-F0003
AIMS AND SCOPE
Atmospheric and Oceanic Science Letters (AOSL) publishes short research letters on all disciplines of the atmosphere sciences and physical oceanography. Contributions from all over the world are welcome.  相似文献   

18.
《大气和海洋科学快报》2014,(5):F0003-F0003
AIMS AND SCOPE Atmospheric and Oceanic Science Letters (AOSL) pub- lishes short research letters on all disciplines of the atmos- phere sciences and physical oceanography. Contributions from all over the world are welcome.  相似文献   

19.
20.
正Aims Scope Advances in Atmospheric Sciences(AAS)is an international journal on the dynamics,physics,and chemistry of the atmosphere and ocean with papers across the full range of the atmospheric sciences,co-published bimonthly by Science Press and Springer.The journal includes Articles,Note and Correspondence,and Letters.Contributions from all over the world are welcome.  相似文献   

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