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1.
Drought and human adjustment in Saudi Arabia 总被引：1，自引：0，他引：1
Abdulla Ahmed Al-Taher 《GeoJournal》1994,33(4):411-422
Drought is one of the natural hazards which causes death and damage for property particularly in drylands of the world. Drought as a natural hazard tends to limit and disrupt human activities. On the other hand, man has tried to adjust his living conditions to this hazard. The adjustment to drought is different from one country to another. Adjustment to drought is affected by culture, income, and by the political system in the country. In the case of Saudi Arabia adjustment to drought hazard is usually the work of both individuals, and government. The Saudi Arabian government has spent large sums of money to reduce impact of drought hazard. 相似文献
2.
Artificial groundwater recharge to a semi-arid basin: case study of Mujib aquifer,Jordan 总被引：1，自引：1，他引：0
Mujib watershed is an important groundwater basin which is considered a major source for drinking and irrigation water in
Jordan. Increased dependence on groundwater needs improved aquifer management with respect to understanding deeply recharge
and discharge issues, planning rates withdrawal, and facing water quality problems arising from industrial and agricultural
contamination. The efficient management of this source depends on reliable estimates of the recharge to groundwater and is
needed in order to protect Mujib basin from depletion. Artificial groundwater recharge was investigated in this study as one
of the important options to face water scarcity and to improve groundwater storage in the aquifer. A groundwater model based
on the MODFLOW program, calibrated under both steady- and unsteady-state conditions, was used to investigate different groundwater
management scenarios that aim at protecting the Mujib basin. The scenarios include variations of abstraction levels combined
with different artificial groundwater recharge quantities. The possibilities of artificial groundwater recharge from existing
and proposed dams as well as reclaimed municipal wastewater were investigated. Artificial recharge options considered in this
study are mainly through injecting water directly to the aquifer and through infiltration from reservoir. Three scenarios
were performed to predict the aquifer system response under different artificial recharge options (low, moderate, and high)
which then compared with no action (recharge) scenario. The best scenario that provides a good recovery for the groundwater
table and that can be feasible is founded to be by reducing current abstraction rates by 20% and implementing the moderate
artificial recharge rates of 26 million(M)m3/year. The model constructed in this study helps decision makers and planners in selecting optimum management schemes suitable
for such arid and semi-arid regions. 相似文献
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4.
2004年春季沙尘天气对和田市空气质量的影响 总被引：2，自引：0，他引：2
利用沙尘暴监测网数据、常规气象资料以及MICAPS系统环流形势资料,对和田市2004年春季沙尘天气产生的污染进行了详细的对比分析。研究结果表明：和田市春季污染相当严重,主要以沙尘污染为主。整个春季79％时间API（环境污染指数）指数均达到500,且45％时间可吸入颗粒物PM10在TSP巾的浓度比例达50％。不同天气系统对和田市空气的污染贡献不同。从东路影响和田市的天气系统、高压底部型地面系统和浮尘天气所造成空气污染相当严重。其余天气系统和天气现象所产生的污染较小。 相似文献
5.
Development of groundwater modeling for the Azraq Basin, Jordan 总被引：2，自引：1，他引：1
The three-dimensional groundwater flow model MODFLOW was applied to simulate water level change in the complex multi-aquifer
systems (the Upper and Middle Aquifers) of the Azraq basin. The model was calibrated by matching observed and simulated drawdown
for steady and transient states over the period 1970–1992. Drawdown data for the period 1993–1997 were used to test the model's
ability to predict the response of the aquifers. The model performed well in representing the water level contours of the
Upper and Middle Aquifers for steady state calibration. Agreement between the observed and simulated drawdowns was obtained
for transient state calibration. To predict the aquifer system responses for the period of 1997–2025, four different pumping
schemes (scenarios) have been investigated. The first scenario (present pumping rate) reveals that there will be approximately
a 25 m drop in the water level at the well-field area in 2025. However, the worst scenario (pumping rate at 1.5 times the
present rate) reveals an approximate 39 m drop in the water level at the well-field area in 2025. The safe yield for the Upper
Aquifer System was found to be about 25 million cubic meters (MCM) yearly.
Received: 24 June 1999 · Accepted: 30 November 1999 相似文献
6.
This paper is a sequel to an earlier article of the same title. The two formal analytical solutions of the Ideal Resonance Problem developed respectively by Garfinkel and Jupp are here compared, atsecond-order in the appropriate small parameter, with numerical integrations; the second-order circulation solution for Jupp's theory being presented for the first time. It transpires that throughout most of the deep resonance regime the second-mentioned solution provides greater accuracy. In addition, it is demonstrated that the first solution is not appropriate when general initial values of the variables are prescribed. 相似文献
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Rebecca E. Eager Sethu Raman Teddy R. Holt Douglas Westphal Jeffrey Reid Jason Nachamkin Ming Liu Abdulla Al Mandoos 《Pure and Applied Geophysics》2007,164(8-9):1747-1764
A statistical evaluation of the Coupled Ocean/Atmosphere Mesoscale Prediction System (COAMPS®) was performed over the Arabian Gulf region for the period, 1 August to 5 October, 2004. Verification skill scores of bias and root-mean-square error were estimated for surface variables and for vertical profiles to investigate any diurnal variations. The model predictions of boundary-layer heights are compared with the observations at Abu Dhabi, United Arab Emirates. The Middle East presents challenges to numerical weather prediction due to complex land-ocean-land mesoscale processes. An independent data set of surface measurements from 50 stations in the UAE was available from the Department of Water Resources Studies, Abu Dhabi for model verification. The results indicate a diurnal variation in the model errors. The errors are small considering the magnitudes of the observed variables. Errors in the coastal region can be attributed to the differences in the timing of the onset of sea and land breeze circulations in the simulations as compared to the observations. Errors are relatively smaller in the offshore locations. 相似文献
9.
喀纳斯自然保护区地衣生态地理分布的研究 总被引：1，自引：0，他引：1
根据1985年以来实地考察的基础上,对保护区自然地理条件和地衣生长发育的地理背景进行了分析,对地衣植被的生态地理分布规律进行了初步探讨.并对地衣植被进行了生态分类. 相似文献
10.
Calcite and quartz veins in the gabbroic and dunite rocks of the Semial ophiolite (UAE) were selected for fluid inclusion analysis. The inclusions contain both aqueous low-salinity and hydrocarbon-dominated fluids. Mi-crothermometry data indicate that the aqueous fluids contain 0.22 to 1.45 equivalent wt% NaCl and occasionally contain traces of hydrocarbons. Homogenization to liquid occurred between 91 and 152℃. Modeling based on these fluid inclusion observations indicates that the trapping conditions of t... 相似文献