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1.
基于社会经济学模型对中国未来不同社会经济发展情景下土地利用变化的预测资料,利用区域气候模式RegCM3,重点研究了南水北调工程建成后,对中国北方13个省(区)范围内农田、农林混作区和草地等进行大面积灌溉所产生的区域气候效应。结果显示:大面积农业灌溉对中国区域气候影响明显,主要受灌区及其邻近地区土壤湿度、近地层空气湿度、总云量、潜热通量、降水量等均呈增加趋势,地表温度、感热通量及500 hPa位势高度将降低。灌溉后受灌区土壤湿度的增加,不仅使受灌区气候环境发生变化,还通过动量、热量及水汽交换对邻近地区气候产生影响。 相似文献
2.
E. Annette Hernandez Venkatesh Uddameri Sreeram Singaraju 《Environmental Earth Sciences》2014,71(6):2687-2699
Energy requirements constitute a significant cost in groundwater production and can also add to a large carbon footprint when fossil fuels are used for power. Wind-enabled water production is advantageous as it minimizes air pollution impacts associated with groundwater production and relies on a renewable resource. Also, as groundwater extraction represents a deferrable load (i.e., it can be carried out when energy demands within an area are low), it provides a convenient way to overcome the intermittency issue associated with wind power production. Multiple turbine wind farms are needed to generate large quantities of power needed for large-scale groundwater production. Turbines must be optimally located in these farms to ensure proper propagation of kinetic energy throughout the system. By the same token, well placement must reconcile the competing objectives of minimizing interferences between production wells while ensuring the drawdowns at the property boundary are within acceptable limits. A combined simulation–optimization based model is developed in this study to optimize the combined wind energy and water production systems. The wind farm layout optimization model is solved using a re-sampling strategy, while the well field configuration is obtained using the simulated annealing technique. The utility of the developed model is to study wind-enabled water production in San Patricio County, TX. Sensitivity analysis indicated that identifying optimal placement of turbines is vital to extract maximum wind power. The variability of the wind speeds has a critical impact on the amount of water that can be produced. Innovative technologies such as variable flow pumping devices and aquifer storage recovery must be used to smooth out wind variability. While total groundwater extraction is less sensitive to uncertainty in hydrogeological parameters, improper estimation of aquifer transmissivity and storage characteristics can affect the feasibility of wind-driven groundwater production. 相似文献
3.
The same model previously used to deduce an acceptable first order picture of the present zonally averaged macroclimate is now solved for the climatic response to the “glacial” surface boundary conditions that prevailed at 18,000 BP in the northern hemisphere. The equilibrium solution obtained gives the distributions with latitude of the mean temperature, wind, humidity, precipitation, evaporation, heat balance, transient baroclinic eddy statistics (i.e., kinetic energy of the meridional wind and meridional flux of heat, momentum, and water vapor), and the energy integrals. In general terms, the solution shows the glacial atmosphere to be colder and drier than at present, with an intensified polar front, stronger mean zonal and poloidal winds, more intense transient baroclinic eddies (storms) transporting heat, momentum and water vapor poleward at higher rates, and reduced precipitation and evaporation. Also evident is an equatorward shift of the climatic zones (as delineated by the mean surface zonal winds, the poloidal motion, and the difference between mean evaporation and precipitation), particularly in higher latitudes. Other properties of the solution, such as the effect of zonal wind changes on the length of the day, are discussed. 相似文献
4.
河套干旱地区夏季边界层结构特征观测分析 总被引：2，自引：0，他引：2
利用2013年夏季7月爱尔达K/LLX802J型机动式边界层风廓线雷达获取的三维风场资料和银川站高空气象探测资料,对河套干旱地区夏季边界层日变化特征进行了分析.结果表明:爱尔达K/LLX802J型机动式风廓线雷达能较好的反映并分辨出夏季河套干旱地区边界层内大气湍流和风场的演变过程.夏季7月河套干旱地区边界层高度白天平均为2127.2 m,夜间平均为1760.7 m,白天边界层高度比夜间平均高366.5 m.河套干旱区夏季地表非绝热加热对边界层的影响主要集中在800 m以下,800~2000 m高度边界层则主要受昼夜交替和大尺度天气系统的影响.夏季7月河套干旱地区边界层风速在300 m以下随高度增加而增大,离地500 m以下边界层易在北京时间07:00-11:00和18:00-21:00时段发生风速切变;300 m以下边界层白天盛行西南偏南风、夜间盛行南风,300~2000 m高度边界层白天和夜间均盛行东南风;离地300 m以下边界层易在夜间21:00-23:00时出现风向切变.夏季7月白天河套干旱地区边界层大气垂直速度在300 m高度以下随高度增加而增大,由0.3 m·s-1增大到0.6 m·s-1,夜间边界层大气垂直速度在200 m高度以下随高度增大而增大;300 m高度以上边界层大气垂直速度无论昼夜随高度变化均较小. 相似文献
5.
The water resource and its change of mountainous area are very important to the oasis economic system and ecosystem in the arid areas of northwest China. Accurately understanding the water transfer and circulation process among vegetation, soil, and atmosphere over different hydrological units in mountainous areas such as snow and ice, cold desert, forest and grassland is the basic scientific issue of water research in cold and arid regions, which is also the basis of water resource delicacy management and regulation. There are many research results on the hydrological function of different land covers in mountain areas, basin hydrological processes, however, there are only very limited studies on the water internal recycle at basin scale. The quantitative study on the mechanism of water internal recycle is still at the starting stage, which faces many challenges. The key project “Study on water internal recycle processes and mechanism in typical mountain areas of inland basins, Northwest China” funded by National Natural Science Foundation of China will select the Aksu River and Shule River Basin, which have better observation basis, as study area. The internal mechanism of moisture transfer and exchange process of different land cover and atmosphere, the internal mechanism of water cycle in the basin, and water transfer paths in atmosphere will be studied through enhancing runoff plot experiments on different land cover, analyzing the mechanism of water vapor transfer and exchange between different land covers in the watershed by isotope tracing on the water vapor flux of vegetation water, soil moisture and atmospheric moisture, improving the algorithms of remote sensing inversion and ground verification on land surface evapotranspiration on different land cover, and analyzing the water vapor flux from reanalysis data, and the coupling modeling of regional climate model and land surface process model. At last, the effect of different land cover in hydrological process of mountain area, and the impact of land cover on downstream oasis will be systematically analyzed. 相似文献
6.
1979-2016年我国东北地区空中水汽状况及变化趋势分析 总被引：1，自引：1，他引：0
水汽是形成云和降水的物质基础,与全球水分循环和能量平衡密切相关,对天气和气候具有重要影响。基于NCEP/NCAR月值再分析资料,综合分析我国东北地区上空不同高度层位比湿的气候学特征和长期趋势变化,同时分析了整层积分水汽通量的季节变化。结果表明：东北地区空中水汽集中分布于500 hPa以下,1979年至20世纪末低层比湿呈增加趋势,2000年后转为缓慢下降,但2012年以来波动回升。此外,东北地区比湿及水汽通量季节差异明显,夏季水汽含量最多,冬季最少,秋季多于春季;东北地区水汽含量最大值出现于7月,最低值出现在每年12月至次年1月。水汽来源受东亚季风系统影响明显,夏季水汽源地主要为南海,渤海和黄海对东北地区夏季水汽也有一定贡献;其他季节水汽主要来源于西风带输送。 相似文献
7.
中国北方土壤风蚀问题研究的进展与趋势 总被引：70，自引：0，他引：70
土壤风蚀是中国北方土地退化的主要原因之一。国内土壤风蚀的研究工作相对比较薄弱，所取得的进展主要包括区域性的土壤风蚀分布地带性规律和不同时间尺度的准周期性规律，描述性的风蚀强度分级与危害评价，单因子风蚀过程的风洞实验，农田风蚀防治等方面。今后的研究趋势主要表现在土壤风蚀的物理本质、影响因素及发展动态的综合研究，土壤理化性质与表面性质对抗蚀性的影响及其与风蚀的反馈关系，土壤风蚀的基本过程及防治原理，土壤风蚀预报方程与数字模拟，土壤风蚀影响评价模型，土壤风蚀与土地利用以及全球变化的关系，各种观测与实验设备的研究等方面。 相似文献
8.
黑河流域陆地—大气相互作用研究的几点思考 总被引：4，自引：2，他引：2
陆地和大气之间是相互作用、相互影响的,不仅陆面分布与地表过程对大气变化有着响应过程,而且陆面物理过程、地表特征分布对大气过程也有着重要影响。我国西北地区地形分布极不均匀,是水资源变化和气候变化的敏感区与脆弱地区。这里,由于海拔高度起伏造就了以水为主线的上游山区冰雪、冻土—中游森林、绿洲—下游戈壁荒漠的多个自然景观带共存的内陆河流域,是开展陆—气相互作用研究的理想场所。文章集中黑河流域水循环过程、冰雪/冻土与大气相互作用、降水异质性、人类活动影响以及尺度等问题,阐述了流域研究现状以及研究热点,指出发挥各学科优势,将大尺度的大气过程与中间尺度和小尺度的陆面水文/生态过程结合,建立流域尺度大气—水文—生态过程真正的双向耦合模式,不仅研究气候变化对陆面水文、生态的影响,同时探讨陆面小尺度过程对大气的反馈机理,探索流域尺度的水循环过程和驱动机理,为水资源合理利用提供理论基础。 相似文献
9.
10.
众多研究表明黄河源区受气候变化影响,土壤活动层逐渐下降。土壤温、湿度是陆面过程及地球系统中的重要物理量,它们通过影响地表能量和物质交换而影响大气环流和降水等。利用WRF（Weather Research and Forecasting）模式,选取2个典型年分别设计了2个控制试验和2个敏感性试验来探讨土壤初始状况变化对区域水循环的影响,通过再循环降水率定量描述不同气候背景下陆面对黄河源区水循环的影响,并尝试从环流角度进一步分析土壤初始状况改变对源区水循环影响的物理机制。结果表明：陆面对水循环的影响受大尺度环流背景场影响较大,较弱的环流背景下再循环降水率较强环流背景大5%左右。土壤初始状况对水循环要素有一定程度的影响。土壤初始温度升高/降低,水汽通量增多/减少,后期降水增大/减小。不同环流背景下,土壤记忆时间不同,在弱的环流背景下,土壤记忆时间要长,初始状况扰动可持续1～2个月。 相似文献
11.
The terrestrial water cycle is the mutual transformation of surface and near-surface water, which controls the supply of fresh water resources. It is affected by human activities, solar radiation and gravity, as well as climate and environmental conditions. Inter-basin water transfer, irrigation, crop cultivation and harvesting, exploitation of groundwater water and other human activities lead to the change of spatial and temporal distribution of soil moisture, the underground water level, surface albedo, surface evaporation, as well as water and energy exchange between land surface and atmosphere. Human water use generates important feedback on the climate and changes the processes of the terrestrial water cycle significantly. The spatial and temporal distribution of precipitation in China is uneven. In addition, human activities further exacerbate the fragility of water resources and the contradiction between supply and demand, posing a serious challenge to the sustainable development of social economy. Therefore, understanding the laws and mechanisms of terrestrial water cycle change is very important for water resources utilization and human sustainable development. From the perspective of climate change and human activities, this paper summarized the impact of human activities on terrestrial water cycle and the progress of climate feedback research. It is urgent to consider the evolution of terrestrial water cycle and its climate under the dual impact of natural and human activities, and develop the large-scale land surface hydrological models and climate models with human water use, crop planting and irrigation, lateral groundwater flow. From the perspective of a fully coupled system, we need quantitatively to assess the climate feedback of human water use and its impact on the terrestrial water cycle process, and to explore its mechanism. We need to distinguish the contribution of human water activities and global climate change to the evolution of terrestrial water cycle in the context of climate change, and to propose water resources management strategies to address climate change. 相似文献
12.
LIU Shu-hua~ 《地球科学进展》2004,(Z1)
Based on the existing Land Surface Physical Process Models(Deardorff, Dickinson, LIU, Noilhan, Seller, ZHAO), a Comprehensive Land Surface Physical Process Model (CLSPPM) is developed by considering the different physical processes of the earth‘s surface-vegetation-atmosphere system more completely. Compared with SiB and BATS, which are famous for their detailed parameterizations of physical variables, this simplified model is more convenient and saves much more computation time. Though simple, the feas... 相似文献
13.
The Kuroshio Extension （KE） is the key area where the water heats the atmosphere in the northwestern Pacific Ocean in winter. Previous studies show that the active eddies in the KE area can affect sea surface temperature and thus sea surface winds. The present study reviewed the progress about the influences of the eddies on local atmosphere in recent years. Analysis and comparison were made especially for the achievements from shipboard sounding data, satellite observations and numerical experiments. Based on the geostrophic adaptation theory involved in atmospheric anomalies induced by the eddies, the following new scientific deductions were suggested: Air pressure adjustment mechanism dominated in the atmospheric response to eddies under the conditions of weaker wind speed over the eddies. The influence of eddies was often limited in the atmospheric boundary layer. On the other hand, vertical mixing mechanism played a major role in the response of the atmosphere to warm (cold) eddies when air moved faster over the eddies. Surface wind speed increased (decreased) over the warm (cold) water. Significant wind convergence took place downwind the warm water, and large amount of water vapor was transported also downwind from the warm water surface. The positive feedback between water vapor condensation and rising air forced by the surface convergence provided necessary conditions for the development of strong convection in atmosphere. These deductions will be conducive to further depicting the impact of oceanic eddies on the atmosphere quantitatively. 相似文献
14.
利用2015年夏季玛曲高寒草甸观测资料,从中选取7月10个连续完整的观测日,分析了近地层气象要素、地表辐射和能量传输以及CO2通量日变化特征。结果表明：夏季玛曲地区气温和比湿昼夜差异较大,最大温差为19.2 ℃,平均风速为2.7 m?s-1,风向以东风为主。晴天条件下向下短波辐射可达1 200 W?m-2左右,平均地表反照率为0.22,均大于藏北那曲地区。净辐射峰值可达850 W?m-2左右,陆-气间能量传输以潜热输送为主。10 d能量闭合度平均值为0.61,能量不平衡程度较大。夏季玛曲高寒草甸表现为“碳汇”,CO2通量平均值为-0.20 mg?m-2?s-1,晴天碳吸收最大速率为-14.05 mg?m-2?s-1,显著大于阴天,最大碳吸收时长为13 h,CO2密度平均值为530.7 mg?m-3。 相似文献
15.
Bharat M. Sule 《Journal of the Geological Society of India》2018,92(1):107-110
Wind energy is a popular from the non-conventional energy sources in the World. In India states like Tamil Nadu, Gujarat, Orissa, and Maharashtra are as regarded as superior areas with respect to this type energy. The installed capacity of wind in India till December 2010 was 13,056.37 MW, principally distributed throughout the Maharashtra, Tamil Nadu, Rajasthan, Karnataka, Andhra Pradesh, Gujarat, Kerala, Madhya Pradesh, West Bengal, etc. In Maharashtra, there are 38 wind farms and the 3655 wind machines are installed with the 3431.86MW capacity of power generation up to September 2013. In Satara district, 17 wind sites and also other some sites are discovered. At present there are 1636 wind turbines are installed with its capacity of power generation is 1122.61MW and the production of wind energy of 2183745.15KWh average per annum in Satara district.The main objectives of the present paper are to assess the scope of non-conventional energy resources especially the power generation from wind and to analyze the trend and distribution of the wind mills and wind farms in Satara district. It is find out the amount of recovered from the power generation comes around 12 years without subsidy and around 8 years with subsidy. The total life span of wind turbines is 25 years. It is very much clean and does not cause any problem to the environment as well as to the survival on the surface of the earth. Therefore, it is inferred that the generation of power from wind is not only cheaper and permanent energy source but also a non-polluting, freely available source. It is helpful for the development of economically and socially in a region especially in rural development. With these consequences the income level will increase and it will further help in minimising the social disparities. 相似文献
16.
以湄公河流域为研究区,采用区域气候模式RegCM3为模拟工具,以根系层土壤含水量为代表性指标,对A1B情景下未来研究区月尺度农业干旱进行了预估。基于地表能量平衡原理,系统分析了降水、蒸发、地表温度和根系层土壤含水量等农业干旱主要影响因素与区域气候模式模拟的大气环流、地表感热通量、地表潜热通量、地表净通量之间的联系和变化规律,从气陆间能量和水汽通量平衡角度,对农业干旱发生机理进行了识别。预估结果表明:从年内各月地表净通量和地表温度变化来看,未来春末(6月)和秋末(10月)湄公河流域温度增加明显,且土壤含水量减少也较为明显;同时,这两个时段蒸发旺盛和降水减少的趋势,有可能导致流域局部地区(尤其是非灌溉农业区)农业干旱的发生。 相似文献
17.
分析了中国西北地区上空的水汽汇聚过程———平流输送与辐合输送,为西北地区降水过程数值模拟的参数化提供依据.分析表明:中国西北大部分地区为负的水汽平流输送,从上风方向得到的水汽输入小于水汽输出,是水汽的净流失区;中国西北地区中部为大范围负的水汽辐合输送,当地的水汽由风场向外扩散,加剧了当地的水分流失,是水汽扩散区;在水汽净输送的年际变化中,中国西北地区小于华北地区,平流输送呈上升趋势,辐合输送下降,平流的相对贡献在增加;在与大气环流系统的关系中,中国西北地区水汽的平流输送主要受西风带影响,辐合输送与南亚夏季风有显著相关.变化趋势表明西风的作用在加强. 相似文献
18.
风浪在自然水体中广泛存在,是浮游生物生存环境的本质特征。在湖泊（特别是浅水湖泊）中,风浪过程广泛影响着水体的物理、化学特性,并直接和间接对浮游生物产生重要影响。综述了风浪对湖泊浮游动物、浮游植物和浮游细菌影响的相关研究。风浪对浮游生物的时空分布及其在塑造浮游生物系统的结构和功能中发挥了至关重要的作用:风浪条件在浮游生物的行为、营养盐吸收速率和通量、捕食及其生长、竞争和演替等方面均具有广泛且重要的影响,并显著影响着水体食物网的结构和功能,最终对湖泊生态系统的结构和功能产生潜在的影响。提出了未来研究的主要方向为进一步揭示全球气候变化条件下风浪在湖泊中的生态环境效应,为富营养湖泊的治理和管理提供新的认识和决策支持。 相似文献
19.
青藏高原西部陆面过程特征的模拟分析 总被引：15，自引：4，他引：11
利用1998年5月1日至9月18日狮泉河自动气象站(AWS)的观测资料作为强迫场,运用改进的陆面过程模式CoLM(Common Land Model),对青藏高原西部的陆面特征进行了模拟研究.结果表明,该模式能够较好地模拟出高原地区的陆面特征.在高原西部地表能量平衡过程中,感热通量占主要地位,潜热通量较小,但在高原西部的湿季,潜热通量也是不可忽略的.在5月及6月初表层土壤频繁的发生水分相变,使土壤在相变过程中不断地吸收和释放潜热.降水及土壤表层频繁的冻结-消融使地表有效通量(感热+潜热)发生变化.有效辐射中的感热、潜热的分配,即Bowen会发生变化,进一步影响到对大气的加热及大气水汽输送情况,大气状况的改变又反过来影响地表蒸散及土壤持水能力,使土壤水分状态和含量发生变化. 相似文献
20.
The influence of atmospheric forcing on the flow and heat transports in the lower Chesapeake Bay and the adjacent coastal ocean were studied by comparing nontidal sea level and sea surface temperature variations in this region with meteorological data for 1992. Northeasterly and southwesterly winds caused the greatest changes in mean sea level (greater than 0.25 m) throughout the year. Northeastely winds caused a more rapid response than southwesterly winds, causing sea-level rises in less than 6 h. Barometric pressure changes typically contributed approximately 10% to extreme sea-level variations and were less influential than wind stress in most cases. Wind forcing was also responsible for summer events in which the horizontal water temperature gradient between two near-surface locations in the vicinity of the bay mouth vanished. These zero-gradient events corresponded to inflows and outflows at the bay's entrance caused by northeasterly and southwesterly winds, respectively. Wind-induced advection outside the lower Chesapeake Bay was additionally responsible for extreme heat flux variations. Heat gains and losses during the spring and fall occurred in pulsating events related to wind direction but were probably not connected to lower bay processes. 相似文献