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Talal Al-Awadhi

Bio: Talal Al-Awadhi is an academic researcher from Sultan Qaboos University. The author has contributed to research in topics: Land use & Geology. The author has an hindex of 9, co-authored 35 publications receiving 242 citations.

Papers
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Journal ArticleDOI
TL;DR: In this article, cellular automata (CA)-Markov and geospatial techniques were utilized to assess and project urban growth and land cover changes in Nizwa city, Al Dakhliyah governorate, Oman.

163 citations

Journal ArticleDOI
08 Dec 2020
TL;DR: The directional pattern of CO VID-19 cases has moved from northeast to northwest and southwest, with the total impacted region increasing over time, and the results indicate that the rate of COVID-19 infections is higher in the most populated areas.
Abstract: Coronavirus disease (COVID-19), caused by acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is a worldwide challenge effecting millions of people in more than 210 countries, including the Sultanate of Oman (Oman). Spatiotemporal analysis was adopted to explore the spatial patterns of the spread of COVID-19 during the period from 29th April to 30th June 2020. Our assessment was made using five geospatial techniques within a Geographical Information System (GIS) context, including a weighted mean centre (WMC), standard deviational ellipses, Moran’s I autocorrelation coefficient, Getis-Ord General-G high/low clustering, and Getis-Ord $$G_{i}^{*}$$ statistic. The Moran’s I-/G- statistics proved that COVID-19 cases in datasets (numbers of cases) were clustered throughout the study period. The Moran’s I and Z scores were above the 2.25 threshold (a confidence level above 95%), ranging from 2274 cases on 29th April to 40,070 cases on 30th June 2020. The results of $$G_{i}^{*}$$ showed varying rates of infections, with a large spatial variability between the different wilayats (district). The epidemic situation in some wilayats, such as Mutrah, As-Seeb, and Bowsher in the Muscat Governorate, was more severe, with Z score higher than 5, and the current transmission still presents an increasing trend. This study indicated that the directional pattern of COVID-19 cases has moved from northeast to northwest and southwest, with the total impacted region increasing over time. Also, the results indicate that the rate of COVID-19 infections is higher in the most populated areas. The findings of this paper provide a solid basis for future study by investigating the most resolute hotspots in more detail and may help decision-makers identify targeted zones for alleviation plans.

44 citations

Journal ArticleDOI
TL;DR: In this paper, the spatial and temporal changes of daily temperature extremes are investigated over Egypt using a standard set of 23 indices, and the results demonstrate that the frequency, intensity, and persistence of warm extremes increased significantly over the study period, with a clear spatial gradient from southeast to northwest.

39 citations

Journal ArticleDOI
TL;DR: In this paper, the authors investigated changes in air quality conditions during the restricted COVID-19 lockdown period in 2020 across 21 metropolitan areas in the Middle East and how these relate to surface urban heat island (SUHI) characteristics.

37 citations

Journal ArticleDOI
TL;DR: In this article, the spatial and temporal variability of drought in Oman was assessed for the period 1979-2014 using the Standardized Precipitation Index (SPI) and the standardized precipitation evapotranspiration index (SPEI) at both seasonal (3 months) and annual (12 months) timescales.

25 citations


Cited by
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Book ChapterDOI
01 Jan 1974
TL;DR: The ultimate source of water for plants is precipitation; rain falling upon soil penetrates it at a rate depending upon the physical properties of that particular soil; snow and hail do the same after melting as discussed by the authors.
Abstract: The ultimate source of water for plants is precipitation; rain falling upon soil penetrates it at a rate depending upon the physical properties of that particular soil; snow and hail do the same after melting. If the rate of rainfall or the rate of production of water by melting exceeds the infiltration rate, then surface runoff occurs and the excess water drains into streams and eventually reaches the sea. That water which penetrates the soil replenishes the soil reservoir and when this is filled to capacity (see chapter 3) the surplus drains through into the aquifers. These are strata such as sand or chalk which can hold substantial quantities of recoverable water. Water held in the soil reservoir is drawn into plant roots and up their stems to be evaporated from the leaves back into the atmosphere, where it rejoins water evaporated from the sea, lakes and rivers and from the surface of wet soil. This so-called hydrological cycle (figure 1.2) depends for its continuance upon energy derived from the sun’s radiation and as will be shown in later chapters its rate is governed largely by meteorological factors.

626 citations

01 Apr 2013
TL;DR: It is found that wide areas of the world display a strong relationship between the number of hot days in the regions’ hottest month and preceding precipitation deficits, and effects of soil moisture-temperature coupling are geographically more widespread than commonly assumed.
Abstract: Global warming increases the occurrence probability of hot extremes, and improving the predictability of such events is thus becoming of critical importance. Hot extremes have been shown to be induced by surface moisture deficits in some regions. In this study, we assess whether such a relationship holds at the global scale. We find that wide areas of the world display a strong relationship between the number of hot days in the regions’ hottest month and preceding precipitation deficits. The occurrence probability of an above-average number of hot days is over 70% after precipitation deficits in most parts of South America as well as the Iberian Peninsula and Eastern Australia, and over 60% in most of North America and Eastern Europe, while it is below 30–40% after wet conditions in these regions. Using quantile regression analyses, we show that the impact of precipitation deficits on the number of hot days is asymmetric, i.e. extreme high numbers of hot days are most strongly influenced. This relationship also applies to the 2011 extreme event in Texas. These findings suggest that effects of soil moisture-temperature coupling are geographically more widespread than commonly assumed.

416 citations

01 Apr 2015
TL;DR: In this article, the most important frameworks of international regulation in Europe are described, and the interaction of such institutional setting with the scientific initiatives at the same level, and finaly assess how scientific results have been fed with some success into strategies to mitigate pollution levels.
Abstract: Environmental effects of reactive nitrogen (Nr) are a result of intense anthropogenic activities.1 Thy are evident in different parts of the world. Proper treatment is, inter alia, a scale issue. With individual countries in mostof Europe too small for comprehensive coverage of all effects, regulation of pollution in Europe co-emerged with political inegration in general. In this article, we describe the most important frameworks of international regulation in Europe. We als discuss the interaction of such institutional setting with the scientific initiatives at the samelevel, and finaly assess how scientific results have been fed with some success into strategies to mitigate pollution levels.

264 citations

01 Dec 2016
TL;DR: This article analyzed 900 years (1100-2012) of Mediterranean drought variability in the Old World Drought Atlas (OWDA), a spatiotemporal tree-ring reconstruction of the June-July-August self calibrating Palmer Drought Severity Index.
Abstract: Recent Mediterranean droughts have highlighted concerns that climate change may be contributing to observed drying trends, but natural climate variability in the region is still poorly understood. We analyze 900 years (1100-2012) of Mediterranean drought variability in the Old World Drought Atlas (OWDA), a spatiotemporal tree-ring reconstruction of the June-July-August self calibrating Palmer Drought Severity Index. In the Mediterranean, the OWDA is highly correlated with spring precipitation (April-June), the North Atlantic Oscillation (January-April), the Scandinavian Pattern (January-March), and the East Atlantic Pattern (April-June). Drought variability displays significant east-west coherence across the basin on multi-decadal to centennial time scales and north-south anti-phasing in the eastern Mediterranean, with a tendency for wet anomalies in the Black Sea region (e.g., Greece, Anatolia, the Balkans, etc) when coastal Libya, the southern Levant, and the Middle East are dry, possibly related to the North Atlantic Oscillation. Recent droughts are centered in the Western Mediterranean, Greece, and the Levant. Events of similar magnitude in the Western Mediterranean and Greece occur in the OWDA, but the recent 15-year drought in the Levant (1998-2012) is the driest in the record. Estimating uncertainties using a resampling approach, we conclude there is an 89% likelihood this drought is drier than any comparable period of the last 900 years and a 98% likelihood it is drier than the last 500 years. These results confirm the exceptional nature of this drought relative to natural variability in recent centuries, consistent with studies that have found evidence for anthropogenically forced drying in the region.

215 citations

Journal ArticleDOI
TL;DR: In this article, cellular automata (CA)-Markov and geospatial techniques were utilized to assess and project urban growth and land cover changes in Nizwa city, Al Dakhliyah governorate, Oman.

163 citations