秦皇岛市近63年自然降水资源变化特征

利用秦皇岛市1954—2016年逐日降水资料,运用线性趋势法、累计距平、方差分析等数理统计方法,分析了近63 a来秦皇岛市年、季、月自然降水总量与雨日的气候变化特征。结果表明:秦皇岛市年降水量总体呈减少趋势,气候倾向率-15.5 mm/10 a;夏、秋季降水量呈减少趋势,春季呈增加趋势,冬季变化不明显;1月、2月降水变化趋势不明显,7月—10月呈减少趋势,2月—4月、11月—12月呈增多趋势。年雨日明显减少,平均每10 a减少3.05 d,雨日的减少主要表现为小雨日数的减少。年降水强度变化不大,夏、春季降水强度呈增加趋势,秋季呈减小趋势,冬季变化不大。由上可知,年降水量和雨日的同步减少是秦皇岛市近63 a降水变化的明显特征,因此,秦皇岛市自然降水资源呈减少趋势,夏、秋两季变干明显。     

三江源地区空中云水资源人工增雨潜力及其对生态环境影响评估

2011年中国气象局人工影响天气中心提出了CWR-PEP增雨潜力评估方法,文章应用该评估方法对2017～2019年青海省三江源地区人工增雨潜力作了评估,得出:2017～2019年青海省三江源地区人工增雨(雪)共增加降水62.18～93.26亿m~3。其中,飞机增雨作业增加降水51.00～76.51亿m~3,地面增雨作业增加降水11.18～16.75亿m~3,增雨(雪)作业补充了三江源地区水资源短缺,使扎陵湖和鄂陵湖水体面积增加,牧草覆盖度提高,江河源径流量增加。该方法对空中水资源科学合理开发提供了依据,对今后人工增雨潜力评估工作具有一定意义。     

秦皇岛地区干旱趋势分析及人工增雨条件

通过分析秦皇岛地区水资源及人均占有率、气候干旱化之现状及秦皇岛地区降水的特点,发现秦皇岛降水有明显日变化特征（凌晨1～2时和傍晚17～18时降水量较大）。从化学制剂的选择、碘化银成核环境确定、积云增雨的高度判断三个方面提出了人工增雨作业条件,在作业实践中取得了良好效果。     

秦皇岛降水酸碱性及其对环境的影响

由秦皇岛市降水pH值和大气环境数据,分析降水酸碱度的变化、酸雨和强碱性降水的分布、较强碱性降水对环境的影响。结果显示:2006—2018年,降水酸碱性的变化趋势是pH值逐渐增大,13 a间发生酸雨过程158次,且呈明显减少趋势;pH值7的降水共发生152次,pH值7.5的降水发生45次,碱性降水呈显著增多趋势;较强碱性降水对蔬菜生长和产量影响较大,会降低作物的抗病力,增加枯萎率和烂根率,使蔬菜产量减少。     

东部农业区春季干旱变化特征分析及成因初探

利用50多年青海省东部农业区的12站气象资料及青藏高原季风指数研究表明:春季干旱指数SPI变化倾向率为-0.33/10a,呈略减少趋势,减少的趋势不显著;春季东部农业区区域性轻旱、中旱、重旱、特旱分别出现12、5、4、0次,共出现21次,未出现特旱。出现干旱(包括轻旱、中旱和重旱)的几率为38.9%;春季出现过4次明显的区域性大旱,平均每13.5年发生1次,21世纪初以来我省东部农业区出现大旱的几率明显减少;近50年,春季高原季风指数以2.68gmp/a速率增加,增加趋势显著;东部农业区的干旱指数SPI与同期、前期高原季风指数的相关分析表明,高原夏季风越强,东部农业区的降水就越多,干旱指数越小,不易出现旱情;春季干旱指数SPI与同期5月北大西洋—欧洲区极涡强度指数、冬季赤道中东太平洋200hPa纬向风指数成反比,5月北大西洋—欧洲区极涡强度指数、冬季赤道中东太平洋200hPa纬向风指数越强,春季干旱指数SPI越小,春季降水量则偏少,容易发生干旱;与5月多变量ENSO指数、5月北太平洋遥相关指数、春季印度洋暖池面积成正比,这些指数较强,则春季高原指数越大,春季降水量较多,不容易发生干旱。     

人工增雨指挥系统构建与研究

为增加有效降水,降低干旱和雾霾等环境污染的影响,保护生态环境安全,研制了以提高开发空中水资源能力为主要目的、基于GIS技术的人工增雨作业决策指挥系统,依托新一代多普勒天气雷达、Micaps数据资料和自动站数据库,应用Microsoft C#语言开发了增雨作业预警和指挥功能、指挥信息和作业信息收集互传功能、增雨效果评估功能、常规业务管理功能,构建了功能较为完善的业务系统。     

近44年秦皇岛市各等级降水日数的时空分布

利用1970—2013年秦皇岛市5个测站逐日降水资料,采用距平百分率、线性趋势法分析了近44 a秦皇岛市不同等级降水日数的时空分布特征和变化规律。结果表明:在时间分布上,秦皇岛市年总雨日数和各等级降水日数均呈减少趋势,暴雨日数减少趋势最不明显。在空间分布上,秦皇岛市年总雨日数和不同等级降水日数自北向南,呈现"多—少—多"的分布特征,北部山区青龙和南部沿海昌黎为多雨日中心,各站年总雨日数和小雨日均呈显著减少趋势。     

秦皇岛湿润生态环境变化

利用线性倾向分析、滑动平均和计算干燥度等方法对秦皇岛市1954-2005年降水、气温、相对湿度、蒸发量、干燥度等变化进行分析研究，结果表明：近50年秦皇岛地区气温逐渐升高，降水减少，气候干燥度普遍增大，生态环境呈干旱化趋势，南部干旱化进程较北部大，90年代后干旱化趋势增大。     

乌兰县近35年气候变化及对生态环境的可能影响分析

利用乌兰气象观测站1981~2015年气温、降水资料,运用气候诊断分析方法,分析近35年来乌兰气温、降水变化特征。结果表明:1981~2015年间乌兰气温存在变暖趋势,年气候倾向率为0.363℃/10a;春、夏、秋、冬四个季节的气候倾向率为0.3℃/10a(秋季)~0.5℃/10a(春季)。春季增温最为明显,冬季和夏季增温较为明显,秋季增温较缓;年平均气温在1996~1997年间发生突变。年降水量主要集中在5~9月份,此时降水量(172.0mm)占年降水量(194.1mm)的88.61%,其余月份的降水量(22.1mm)仅占年降水量的11.39%。1982~1985年、1990~2003年出现降水连续偏少年份,2004~2012年为降水持续偏多年份。从20世纪80年代起,乌兰降水呈现出增多趋势,但突变检验表明:降水虽有增加趋势,但未发生突变性增加。平均气温的增加趋势,在一定程度上能够有效扩大农作物种植面积,延长农作物生长季节,增加农作物品种和产量,提高农作物品质,但也可能会增加干旱、洪涝、冰雹、雷电、雪灾等农牧业气象灾害出现机率。     

2018年玉树隆宝滩湿地恢复型人工增雨作业效果分析

基于2018年青海省玉树州隆宝滩湿地恢复型人工增雨作业情况,利用双比分析统计检验和雷达物理检验方法,对两次增雨作业效果进行了分析,结果表明:(1)作业前雷达回波强度有减弱趋势,随着作业的进行,试验区内雷达回波又出现增强趋势。(2)利用双比分析方法对逐3h降水量的统计分析,2次增雨作业过程的平均作业效果为每3h增加降水量0.35mm,相对增加降水量22.8%。     

宁夏近51年气候变化特征分析

利用宁夏10个气象站1960-2010年日气温和降水资料,对宁夏气温和降水的时空变化特征进行了分析.结果显示:①宁夏整体呈现暖干化趋势,但存在区域间差异.②近51年来宁夏年平均气温呈上升趋势,冬季升温幅度大,秋季升温幅度最小.③年平均降水量总体呈现减小趋势,春季微弱增加,冬季降水量显著增加,夏季降水微弱减少,秋季降水减少明显.④通过Kriging空间差值法分析表明,年平均气温总体呈现由西南向西北递增的趋势,中、北部增温较明显;平均年总降水量总体呈现由西南向西北递减的规律,中、北部降水量减小最为明显.     

HISTORICAL AND ESTIMATED GROUND WATER LEVELS NEAR WINNIPEG,CANADA, AND THEIR SENSITIVITY TO CLIMATIC VARIABILITY1

ABSTRACT: Long term well hydrographs and estimated ground water levels derived from hydroclimatic and biological data were used to evaluate trends within the Upper Carbonate Aquifer (UCA) near Winnipeg, Canada, during the 20th Century. Ground water records from instruments have been kept since the early 1960s and are derived from piezometers in the overlying sediments and in open boreholes in the UCA. Some boreholes extend into an underlying Paleozoic carbonate sequence. Shallow well hydrographs show no obvious long term trends but do exhibit variations on the order of three to four years that are correlated with changes in annual temperature and precipitation at lags up to 24 months. Trends observed in deeper wells appear to be largely related to ground water usage patterns and show little correlation with climate over the past 35 years. Stepwise multiple regression modeled average annual hydraulic head in the shallow wells as a function of regional temperature, precipitation, and tree ring variables. Estimated hydraulic heads had a slightly greater range prior to the 1960s, most prominently during an interval of lowered ground water levels between 1930 and 1942. Regression results demonstrate that moisture sensitive tree ring data are viable predictors of past ground water levels and may be useful for studies of aquifers in regions that lack long, high quality precipitation records.     

A SENSITIVITY ANALYSIS OF THE PALMER HYDROLOGIC DROUGHT INDEX1

ABSTRACT: The sensitivity of the Palmer Hydrologic Drought Index to departures from average temperature and precipitation conditions is examined. A time series of zero index values was calculated and then one monthly temperature or precipitation value was perturbed. The resulting time series shows the effects on the index of one anomalous value. Independent series were calculated for temperature anomalies of plus and minus 1, 3, 5, and 10F and for precipitation anomalies of 25, 50, 75, 125, 150, and 200 percent of normal for each calendar month for Colorado, Indiana, Nevada, New York, Oklahoma, South Carolina, South Dakota, Washington, and Wisconsin. Analysis of the time series showed that the period of time required for the index to reflect actual rather than artificial initial conditions could be more than four years. It was also found that the effects of temperature anomalies are insignificant compared to the effects of precipitation anomalies. In some cases, one anomalous precipitation value could result in established wet or dry spells that last for up to two years. Although not examined in detail, the time series suggest that distributions of index values may be asymmetrical and possibly bimodal.     

秦皇岛地区气候资源及农业气候资源特征分析

利用近50 a秦皇岛气象资料,对该地区气候资源及农业气候资源特征进行了分析总结。结果表明:秦皇岛地区年降水量650～700 mm左右,呈减少趋势。全年80%保证率的降水量为425 mm,存在供需矛盾。蒸发量较降水量明显偏多,直接决定了该地区土壤在自然状态下绝大部分时段处于干旱状态。年平均气温10℃左右,呈上升趋势。平均年太阳辐射总量为5 154 MJ/m2,太阳辐射资源较丰富。秦皇岛地区农时较长,气温稳定通过10℃期间历时192 d,可以实行短生育期作物一年二熟或套作二熟。     

PRECIPITATION CHANGES FROM 1956 TO 1996 ON THE WALNUT GULCH EXPERIMENTAL WATERSHED1

ABSTRACT: The climate of Southern Arizona is dominated by summer precipitation, which accounts for over 60 percent of the annual total. Summer and non‐summer precipitation data from the USDA‐ARS Walnut Gulch Experimental Watershed are analyzed to identify trends in precipitation characteristics from 1956 to 1996. During this period, annual precipitation increased. The annual precipitation increase can be attributed to an increase in precipitation during non‐summer months, and is paralleled by an increase in the proportion of annual precipitation contributed during non‐summer months. This finding is consistent with previously reported increases in non‐summer precipitation in the southwestern United States. Detailed event data were analyzed to provide insight into the characteristics of precipitation events during this time period. Precipitation event data were characterized based on the number of events, event precipitation amount, 30‐minute event intensity, and event duration. The trend in non‐summer precipitation appears to be a result of increased event frequency since the number of events increased during nonsummer months, although the average amount per event, average event intensity, and average event duration did not. During the summer “monsoon” season, the frequency of recorded precipitation events increased but the average precipitation amount per event decreased. Knowledge of precipitation trends and the characteristics of events that make up a precipitation time series is a critical first step in understanding and managing water resources in semiarid ecosystems.     

1961—2008年新疆阿克苏地区降水、温度变化特征

利用阿克苏地区5个气象站1961—2008年的降水和温度资料,对近50 a来该地区气候变化及其趋势进行了分析。各气象站年降水量变化趋势基本一致,总体上都呈增加趋势。除库车县气象站年平均温度呈降低趋势外,其余呈上升趋势。总体上,阿克苏地区年降水量和年平均温度均呈上升趋势。     

Decreased Runoff Response to Precipitation,Little Missouri River Basin,Northern Great Plains,USA

High variability in precipitation and streamflow in the semiarid northern Great Plains causes large uncertainty in water availability. This uncertainty is compounded by potential effects of future climate change. We examined historical variability in annual and growing season precipitation, temperature, and streamflow within the Little Missouri River Basin and identified differences in the runoff response to precipitation for the period 1976‐2012 compared to 1939‐1975 (n = 37 years in both cases). Computed mean values for the second half of the record showed little change (<5%) in annual or growing season precipitation, but average annual runoff at the basin outlet decreased by 22%, with 66% of the reduction in flow occurring during the growing season. Our results show a statistically significant (p < 0.10) 27% decrease in the annual runoff response to precipitation (runoff ratio). Surface‐water withdrawals for various uses appear to account for <12% of the reduction in average annual flow volume, and we found no published or reported evidence of substantial flow reduction caused by groundwater pumping in this basin. Results of our analysis suggest that increases in monthly average maximum and minimum temperatures, including >1°C increases in January through March, are the dominant driver of the observed decrease in runoff response to precipitation in the Little Missouri River Basin.     

黄土高原植被类型变化和空间分布对气象因子变化的响应

利用基于GIS的黄土高原植被类型分布图,结合黄土高原地区标准气象站的气象因子资料,对黄土高原植被类型变化和空间分布对气象因子变化的响应关系进行了分析。结果显示:从东南到西北,年降水量、月平均最高气温、月平均最低气温逐渐减少,年平均气温、全年日照时数、全年最大蒸散量、平均风速逐渐增加,植被类型由东南湿润半湿润森林、半干旱森林草原往西北转变成轻干旱、重半干旱的温性草原、干旱的荒漠半荒漠植被。     

WATER BALANCE AT A LOW-LEVEL RADIOACTIVE-WASTE DISPOSAL SITE1

ABSTRACT: The water balance at a low-level radioactive-waste disposal site in northwestern Illinois was studied from July 1982 through June 1984. Continuous data collection allowed estimates to be made for each component of the water-balance equation independent of other components. The average annual precipitation was 948 millimeters. Average annual evapotranspiration was estimated at 637 millimeters, runoff was 160 millimeters, change in water storage in a waste-trench cover was 24 millimeters, and deep percolation was 208 millimeters. The magnitude of the difference between precipitation and all other components (81 millimeters per year) indicates that, in a similar environment, the water-budget method would be useful in estimating evapotranspiration, but questionable for estimation of other components. Precipitation depth and temporal distribution had a very strong effect on all other components of the water-balance equation. Due to the variability of precipitation from year to year, it appears that two years of data are inadequate for characterization of the long-term average water balance at the site.     

REGIONAL HYDROLOGIC RESPONSE OF LOBLOLLY PINE TO AIR TEMPERATURE AND PRECIPITATION CHANGES1

ABSTRACT: Large deviations in average annual air temperatures and total annual precipitation were observed across the southern United States during the last 50 years, and these fluctuations could become even larger during the next century. We used PnET-IIS, a monthly time-step forest process model that uses soil, vegetation, and climate inputs to assess the influence of changing climate on southern U.S. pine forest water use. After model predictions of historic drainage were validated, the potential influences of climate change on loblolly pine forest water use was assessed across the region using historic (1951 to 1984) monthly precipitation and air temperature which were modified by two general circulation models (GCMs). The GCMs predicted a 3.2°C to 7.2°C increase in average monthly air temperature, a -24 percent to + 31 percent change in monthly precipitation and a -1 percent to + 3 percent change in annual precipitation. As a comparison to the GCMs, a minimum climate change scenario using a constant 2°C increase in monthly air temperature and a 20 percent increase in monthly precipitation was run in conjunction with historic climate data. Predicted changes in forest water drainage were highly dependent on the GCM used. PnET-IIS predicted that along the northern range of loblolly pine, water yield would decrease with increasing leaf area, total evapotranspiration and soil water stress. However, across most of the southern U.S., PnET-IIS predicted decreased leaf area, total evapotranspiration, and soil water stress with an associated increase in water yield. Depending on the GCM and geographic location, predicted leaf area decreased to a point which would no longer sustain loblolly pine forests, and thus indicated a decrease in the southern most range of the species within the region. These results should be evaluated in relation to other changing environmental factors (i.e., CO₂ and O₃) which are not present in the current model.