1961—2010年黄河流域蒸发皿蒸发量变化及影响因子分析

利用黄河流域内61个气象站逐月观测资料,使用Mann-Kendall非参数检验方法对1961—2010年黄河流域小型蒸发皿蒸发量变化趋势进行了分析,并用SVD和多元回归方法检测影响蒸发量变化的因子。结果表明,黄河流域年蒸发皿蒸发量在1961—2010年显著下降,四季中夏季的下降趋势最显著,年和春、夏季蒸发量均在1979年发生突变。上、中、下游的年蒸发量变化率分别为-2.38 mm/a、-2.35 mm/a、-8.35 mm/a,下游下降幅度较大。空间变化分布上,年和春、夏季蒸发皿蒸发量均在黄河流域河源地区、河套地区西部及北部、河南北部有显著下降趋势,在河套地区东部呈显著上升趋势。利用SVD分析发现蒸发量的空间变化与不同因子作用有着显著关联,通过对不同区域内各影响因子的多元回归分析发现流域内蒸发量上升的地区主要是由气温上升所引起,而下降的地区则与风速减小有关。     

湘江流域蒸发皿蒸发量的变化趋势及原因分析

利用1960-2006年湘江流域内44个气象观测站蒸发皿观测资料,采用气候倾向率、相关系数分析法,以及反距离权重插值来分析湘江流域蒸发皿蒸发量的时空变化特征及其影响因子。结果表明：湘江流域年蒸发皿蒸发量在47年间以21.29 mm/10a速率显著减少,通过了90%信度检验;且有75%的站点蒸发皿蒸发量下降趋势显著。从季节变化来看,蒸发皿蒸发量的下降趋势主要在夏季,以15.58 mm /10a的速率显著下降,并通过了99%信度检验。从空间分布来看,湘江流域蒸发皿蒸发量自西南向东北逐渐减少,且下游地区减少趋势最显著。流域饱和差的减小及风速的显著下降导致大部分站点蒸发皿蒸发量呈下降趋势。     

1961-2010年黄河流域蒸发皿蒸发量变化及影响因子分析北大核心CSCD

利用黄河流域内61个气象站逐月观测资料,使用Mann-Kendall非参数检验方法对1961—2010年黄河流域小型蒸发皿蒸发量变化趋势进行了分析,并用SVD和多元回归方法检测影响蒸发量变化的因子。结果表明,黄河流域年蒸发皿蒸发量在1961—2010年显著下降,四季中夏季的下降趋势最显著,年和春、夏季蒸发量均在1979年发生突变。上、中、下游的年蒸发量变化率分别为-2.38 mm/a、-2.35 mm/a、-8.35 mm/a,下游下降幅度较大。空间变化分布上,年和春、夏季蒸发皿蒸发量均在黄河流域河源地区、河套地区西部及北部、河南北部有显著下降趋势,在河套地区东部呈显著上升趋势。利用SVD分析发现蒸发量的空间变化与不同因子作用有着显著关联,通过对不同区域内各影响因子的多元回归分析发现流域内蒸发量上升的地区主要是由气温上升所引起,而下降的地区则与风速减小有关。     

1971-2010年黑龙江省蒸发量气候变化特征

利用1971-2010年黑龙江省63个气象站地面气象观测数据,应用气候趋势系数、气候倾向率等方法分析黑龙江省蒸发皿蒸发量和实际蒸发量的时空演变特征。结果表明：近40 a来,黑龙江省蒸发皿蒸发量总体呈下降趋势,气候倾向率达-62.7 mm/10 a,春季和夏季下降显著。从空间分布看,全省蒸发皿蒸发量呈下降趋势,但局部地区与气候变化趋势并不完全同步。在影响蒸发皿蒸发量的气象因子中,风速和气温日较差是影响其下降的关键因素。黑龙江省大部分地区年实际蒸发量占蒸发皿蒸发量的30 %,实际蒸发量呈微弱上升趋势,但不显著。实际蒸发量与降水、日照时数和气温日较差显著相关,日较差是影响其变化的首要原因。     

河北邢台地区蒸发皿蒸发量的变化特征及影响因素

采用线性倾向估计、累积距平曲线、滑动T检验和完全相关系数法,分析了1972～2011年邢台地区蒸发皿蒸发量的变化特征及其影响因素。结果表明:邢台地区年及4季蒸发量呈现显著下降趋势,其中春季蒸发量的下降趋势最为明显,其次为夏季,年蒸发量的下降主要源于春季、夏季的贡献,年蒸发量在1983年发生突变,之后明显下降。邢台地区年蒸发量与日照时数、平均风速、气温日较差呈正相关,与降水量、相对湿度呈负相关。平均风速、气温日较差和日照时数下降是邢台地区蒸发量减少的主要原因。     

东疆地区蒸发量变化趋势及气象影响因子研究

对东疆地区1961-2001年小型蒸发皿蒸发量及其相关气象影响因子进行了分析,结果表明,东疆地区蒸发量呈显著下降趋势,蒸发量1970年代至1980年代初期的增多和1980年代中期至21世纪初的减少是突变现象;6种气象因子对蒸发的决定程度相对湿度>水汽压>气温>风速>日照时数>净地表辐射,风速与日照时数、相对湿度与水汽压、气温与水汽压、气温与相对湿度的协同作用对蒸发量的决定作用很大.相对湿度的显著增加是导致东疆地区蒸发量逐年减少的重要原因.     

逆“蒸发佯谬”现象个例分析

基于山西大同地区8个气象台站1981—2010年蒸发皿蒸发量及其相关气象要素逐月资料,采用线性倾向估计、累积距平和完全相关系数法,对大同地区逆"蒸发佯谬"现象的蒸发皿蒸发量变化特征及其主要气象影响因素进行分析研究。结果表明:从年变化来看,1981—2010年山西大同地区年蒸发皿蒸发量呈现不显著上升趋势,上升率为44.14 mm·(10 a)-1,这与当前大部分地区蒸发皿蒸发量所表现的"蒸发佯谬"现象相悖。夏、秋、冬季蒸发皿蒸发量均呈现上升趋势,而春季无明显变化趋势,其中夏季上升趋势显著且上升幅度最大。因此,夏季蒸发皿蒸发量对全年贡献最大。大同地区年蒸发皿蒸发量的年代际变化呈现增加趋势,而季节蒸发皿蒸发量的年代际变化特征不尽相同。其中,春季呈现出先减少、后增加的趋势,夏季呈现持续增加趋势,而秋季和冬季则表现出先增加、后减少的趋势。气温是引起大同地区逆"蒸发佯谬"现象的主要影响因素,而日照时数、日较差、降水量对该地区蒸发皿蒸发量变化的影响相对有限。     

青海黄南地区近54年蒸发量变化特征及其影响因子

利用青海省黄南地区近54a(1960—2013年)蒸发量、气温、降水量、日照时数、水汽压等资料,应用地理信息系统、数理统计、线性回归和Mann-Kendall检验等方法分析了黄南地区蒸发量的空间及时间变化趋势,并对黄南地区蒸发量变化特征及其影响因子进行了诊断研究。结果表明:黄南地区年平均蒸发量呈明显的下降趋势,20世纪60—70年代为蒸发量偏多阶段,80年代及后为偏少阶段;黄南地区蒸发量最大的季节是春季和夏季,各季蒸发量均呈减少趋势;黄南地区年蒸发量在1973年发生了由多到少的突变,春、夏、秋、冬季分别发在1973、1975、1976和1974年;分析影响蒸发量的相关因子,蒸发量与日照时数呈显著的正相关关系,与水汽压和降水量呈显著的负相关关系,日照时数的减小是蒸发量减少的主要影响因子。     

1961-2010年青海高原蒸发皿蒸发量变化及其对水资源的影响

利用1961-2010年青海省气象观测资料,分析了青海高原近50年蒸发皿蒸发量的时空分布特征和变化趋势,并采用偏相关及主成分分析法,探讨了青海高原蒸发皿蒸发量变化的气候成因及其对水资源的影响。结果表明：近50 a来青海高原蒸发皿蒸发量呈显著下降趋势,它是热力、水分、动力因子综合作用的结果,在三类因子中,动力及水分因子对蒸发皿蒸发量的影响较大,而热力因子相对较小;区域分析表明,影响东部农业区和柴达木盆地蒸发量的主导因子是平均风速和相对湿度,三江源区为相对湿度,而唐古拉山区为气温日较差。通过分析黄河上游可能蒸散量与地表水资源的关系发现,蒸散量对地表水资源的负效应十分显著,其中夏季蒸散量对于平均流量的影响最为显著,而秋季平均流量对蒸散量的响应最为敏感。     

海南岛蒸发量的变化特征及其影响因子分析

利用海南岛18个气象观测站1966—2001年逐日20cm口径小型蒸发皿蒸发量及气象要素资料,通过数理统计方法分析了海南岛年和四季的蒸发量变化特征及气象因子对蒸发量的影响。结果表明:从时间上看,海南岛年蒸发量变化呈波动式下降,蒸发量的减少主要出现在春季,冬季和夏季次之。从空间上看,年蒸发量呈东北少、西南多的分布,其大值区主要集中在西南部,小值区主要集中在东北部和中部地区。M-K检验说明年与春冬两季蒸发量的变化呈下降趋势且在1994年前后发生突变。影响蒸发量变化的因子中,日照时数和风速是造成蒸发量减小的主要因子,降水量的影响仅次于风速和日照时数,而气温不是造成海南岛蒸发量减小的主要因子,相对湿度可能是海南岛的蒸发量减小的影响因子。     

CHARACTERISTICS AND TRENDS OF CLIMATIC EXTREMES IN CHINA DURING 1959–2014

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.     

Revisiting the Concentration Observations and Source Apportionment of Atmospheric Ammonia

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     

LOW-FREQUENCY CIRCULATION AND EXTENDED-RANGE FORECAST IN CONNECTION WITH AUTUMN EXTREME HEAVY RAINFALL PROCESS IN HAINAN

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.     

AN ATTRIBUTION ANALYSIS OF CHANGES IN POTENTIAL EVAPOTRANSPIRATION IN THE BEIJING–TIANJIN–HEBEI REGION UNDER CLIMATE CHANGE

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.     

ANALYSIS OF “BIMODAL PATTERN” STORM ACTIVITY CHARACTERISTICS OF THE BAY OF BENGAL

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.     

Information for Authors

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

Information for Authors

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.     

Information for Authors

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.     

INFORMATION FOR AUTHORS

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.