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1.
Kuwait experienced severe land degradation over the last 30 years due to different factors. This is reflected in soil loss, crusting, salinization, oil contamination, and vegetation cover deterioration. The recent surface deposits are considered as the local source of sand and dust storms, which have acute environmental hazards on the public health, the State’s economy, and the life quality. They are classified into two main categories: desert and coastal deposits. The distribution of the areas affected by deflation processes and those affected by depositional processes revealed that the northern desert of Kuwait is receiving intense sand supply, but on the other hand, the southern desert of Kuwait has a lower frequency of sand deposits. This study is based on visual comparison between the records of the 1980s and recent field surveys during 2001–2011, as they are the available sources of the relevant information to the scope of the study, to investigate the impact of the anthropogenic activities, the significant role of the aeolian processes, soil type, and climatic conditions on the land degradation, and subsequently the severe loss of vegetation and surfacial cover. A detailed sedimentomorphic map, scale 1:100,000, was prepared for the State of Kuwait based on the topographic map of Kuwait (scales 1:50,000, 1:100,000, and 1:250,000) and photomaps (scale 1:29,000), which were created as per the delineated information from the aerial photos (scale 1:29,000, years 1990, 2001) along with spectral and spatial resolution data of the Radarsat, Landsat-7, IRS-1D (Indian Remote Sensing), ERS, TM, SPOT-4, Advanced Space-borne Thermal Emission and Reflection, and IKANOS data in raw format for Kuwait images for the available years (1989, 1994, and 2000–2004), keeping in view of the terrain in Kuwait and the objective of the study.  相似文献   

2.
The Alxa Plateau has one of the highest frequencies of dust events in China and one of the greatest contributions to East Asian dust. We compiled climate and dust storm data for the Alxa Plateau based on observational data from ten meteorological stations from 1960 to 2005. Our analysis showed that Guaizihu and Minqin dust centers had >26 days per year with dust storms versus 7–13 days for other desert and Gobi regions on the plateau. Variations in dust storm frequency during the study period showed that dust storms increased during the 1960s (until 1972), decreased until the late 1990s, and then increased slightly until 2002. About 75.6% of dust storms occurred in March, April, May, June, and July. Between 78.2 and 88.1% of the dust storms occurred during the daytime and 28.9% of the dust storms occurred between 13:00 and 16:00. The mean durations of dust storms in the Alxa Plateau ranged from 715 to 3,462 min. The annual number of minutes of dust storms averaged >1,800 min in the western Alxa Plateau. Dust storm frequency was inversely related to duration: the longer the average duration, the lower the frequency of such storms.  相似文献   

3.
Satellite images from 2000 to 2010 were used to identify major dust trajectories within seven major deserts in the world. The fallen dust from these trajectories were collected and analyzed. The fallen dust rates tend to be lower downwind. The average samples of the world's fallen dust are negatively skewed trimodal with dominancy of silt size fractions (61 %). Most of the fallen dust within major dust trajectories is fining downwind. The fallen dust from the eastern zones (Taklimakan, Gobi, and Australian deserts) are characterized by higher percentages of feldspars and clay minerals, low carbonate content, and grain surface area in comparison to the Western zones (Sahara and Arabian deserts). The Western Sahara Desert dust is differentiated by the highest depositional rates and average quartz percentage (66 %). The dust samples in this zone contain low carbonates and grain surface area compared to dust from the Eastern Sahara Desert. The dust samples within Northern Arabia and Ethiopian-south Arabia zones show the highest average of carbonate amounts and grain surface area.  相似文献   

4.
Analysis of 20-year time series of water levels in the northeastern Gulf of Mexico has revealed that meteotsunamis are ubiquitous in this region. On average, 1–3 meteotsunamis with wave heights >0.5 m occur each year in this area. The probability of meteotsunami occurrence is highest during March–April and June–August. Meteotsunamis in the northeastern Gulf of Mexico can be triggered by winter and summer extra-tropical storms and by tropical cyclones. In northwestern Florida most of the events are triggered by winter storms, while in west and southwest Florida they appear both in winter and summer. Atmospheric pressure and wind anomalies (periods <6 h) associated with the passage of squalls originated the majority of the observed meteotsunami events. The most intense meteotsunamigenic periods took place during El Niño periods (1997–1998, 2009–2010 and 2015–2016). Meteotsunamis were also active in 2005, a year characterized by exceptionally intense tropical cyclone activity. Meteotsunami incidence varied yearly and at periods between 2 and 5 years. Results from cross-wavelet analysis suggested that El Niño and meteotsunami activity are correlated at annual and longer-period bands.  相似文献   

5.
Dust storms loads analyses—Iraq   总被引：1，自引：1，他引：0  
The dust storms that blow over Iraq were studied from December 2008 to March 2009. The total number of studied dust storms was eight; during each dust storm, samples were collected from the cities of Baghdad, Ramadi, Kut, Basra, Najaf, Karbala, Hilla and Tikrit. The climatic elements with the dust storms types were studied. The results of dust storms analyses reflect their increase in average toward the southwestern direction (average suspended, rising, regional dust storms were 8, 10, 15 days/year, respectively). The average means annual rainfall (in mm), evaporation (in mm), temperature (in °C), and relative humidity percentage indicate that there were remarkable variations in values, with increase of the number of days/years of the dust storms reflecting the effect of the regional climatic change. The results of particle size analyses indicate the texture of most samples range from sandy clayey silt (75%) and clayey sandy silt (25%), and the average dominant grain size have a direct relationship with trajectories of dust storms. Quartz grains were 15% rounded and 85% sub-rounded. Moreover, the dust samples were analyzed and identified by using XRD analyses and Polaroid microscope. The results reflect the following minerals according to their average relative dominant, quartz 58.6%, feldspars 17.3%, and calcite 15.4%, with small amount of gypsum 5.5%. The clay minerals (chlorite, illite, montmorillonite, palygorskite, and kaolinite) were recognized. The analyses of heavy minerals percentages by using the microscope were performed. The results of pollen distribution, in descending order, were Chenopodiaceous, Graminea, Pine, Artemisia, Palmae, Olea, and Typha (reaching 79%, 69%, 63%, 53%, 17%, 9%, and 7% of the counted pollen grains, respectively). The results of microorganisms (i.e., isolated bacteria and fungi), in descending order, were the gram-positive Bacillus species (42.9%), Aspergillus species plus Candida albicans (13.8%), and (8.4%), the gram-negative rods, Escherichia coli (9.5%), the gram-positive Cocci streptococcus pneumonia (6.7%), then the gram-negative rod Enterobacter cloacae (4.3%), Staphylococcus epidermidis, and Staphylococcus (3.9%) and (1.9%). The remaining Gram-negative microorganisms were Pseudomonas aeruginosa (2.7%). Regarding the viral etiology, there is no viral isolate among the work results. The allergens commonly associated with dust storms include fungal spores, plant and grass pollens, and organic detritus represent agricultural area pollen grains.  相似文献   

6.
Sand and dust storms are causing hazards and problems in aviation as well as the dangers and distresses they cause on living things. The low meteorological visibility, the presence of strong winds with gust, and the transport of dust and sand particles by the wind are dangerous on landing and departure of aircrafts, and even on planes that are parked. The main aim of the study is to examine the meteorological conditions causing the dust storm that took place in the Arabian Peninsula on February 28, 2009, and to determine the source of dust caused dust storm, sand storm, blown sand, and blown dust at the airports. Within the scope of the study, aviation routine weather report (METAR) and aviation selected special weather report (SPECI) reports have been assessed at many airports over Arabian Peninsula (AP), the northern part of the AP and North Africa. As model outputs; NCEP–DOE Reanalysis 2 data, BSC–DREAM8B, and HYSPLIT model were used. In the satellite images; METEOSAT MSG dust RGB images, MODIS, and Kalpana-1 data were used. According to obtained results, dust storms were detected in Bahrain, Kuwait, Saudi Arabia, and United Arab Emirates (UAE). At Al-Ahsa Airport in Saudi Arabia, the lowest visibility measured on February 28, 2009, dropping to 200 m, which was dominated by blowing sand. The source region of the dust observed at Dubai Airport in UAE is the eastern regions of the Rub’al Khali Desert located between Saudi Arabia, Oman, and UAE.  相似文献   

7.
Human-driven dynamics of land cover types in the Tarim Basin are able to affect potential dust source regions and provide particles for dust storms. Analyses about dynamics of potential dust source regions are useful for understanding the effects of human activities on the fragile ecosystem in the extremely arid zone and also provide scientific evidence for the rational land development in the future. This paper therefore selected the Tarim Basin, NW China, as a representative study area to reveal spatiotemporal dynamics of land cover and their impacts on potential dust source regions. The results showed that farmland, desert and forest increased by 28.63, 0.64 and 29.27%, while grassland decreased by 10.29% during 1990–2010. The largest reclamation, grassland loss and desertification were 639.17 × 103, 2350.42 × 103 and 1605.86 × 103 ha during 1995–2000. The relationship between reclamation and grassland loss was a positive correlation, while a highly positive correlation was 0.993 between the desertification and grassland loss at different stages. The most serious dust source region was the desertification during 1990–2010 (1614.58 thousand ha), and the serious region was stable desert (40,631.21 thousand ha). The area of the medium and low dust source region was 499.08 × 103 and 2667.27 × 103 ha. Dramatic reclamation resulted in the desertification by destroying natural vegetation and breaking the balance of water allocation in various regions.  相似文献   

8.
The Goldsworthy Chalk Stones, 14 roughly shaped balls of chalk, each approximately 2 m in diameter, were installed in June 2002. Initial assessments by the artist, Andy Goldsworthy, and the Strange Partners commissioning team concluded that they would last for about 2 years. The balls’ disintegration has been measured as part of an ongoing scientific monitoring programme designed to assess their durability and to study controls on rates of chalk weathering. Preliminary assessment of the first 3 years of data shows that 76% of the total mass loss occurred during year 1, 19% during year 2 and 5% during year 3. This might reflect the fact that winter rainfall amounts decreased substantially over the period of study. The west facing sides of the balls have tended to show greater mass loss than those facing east, which might also be a function of exposure to rain. Judging from their present slow rates of weathering, the balls will last for over 200 years but an exceptionally cold wet winter might cause sudden and massive breakdown. Three models of chalk mass weathering are presented. The ongoing scientific monitoring programme will focus experimental work on four key research themes: process, lithology, environment and stress history.  相似文献   

9.
Heavy aeolian deposition is one of the most threatening natural hazards to oases in arid areas. How an oasis affects aeolian deposition is tightly related to the local ecological environments. To examine the effects of oasis on aeolian deposition under different weather conditions, monthly aeolian deposition from April 2008 to March 2009 and additional samples during dust storms in April and May 2008 were collected at four sites along the Qira oasis. The monthly ADRs (aeolian deposition rates) varied greatly with seasons and sites, ranging from 19.4 to 421.2 g/m2/month and averaging 198.8 g/m2/month. Aeolian deposition in the oasis was composed dominantly of sand and silt. Based on the variations of ADRs from the four sites, it can be found that the oasis exhibits two different effects on aeolian deposition under different weather conditions. During dust storms, the oasis demonstrates a significantly shielding effect due to the obstruction of the oasis-protection systems, resulting in most aeolian particles being deposited at the windward side of the oasis. While during non-dust storm periods with weak winds, the oasis exhibits an “attracting” effect on aeolian deposition, leading to a higher ADR inside the oasis. Owing to the annual ADR is dominated by the non-dust storm ADR in Qira, the oasis seems to become an important aeolian deposition area caused by the “attracting” effect of the oasis.  相似文献   

10.
Street dust from 29 locations, in some of the busiest parts of north and south Kolkata, was analysed for heavy metal composition. The decreasing order of average metal concentrations (mg kg?1) found was Mn (390) > Pb (380) > Zn (300) > As (96) > Cu (61) > Cr (40) > Co (13) > Ag (2.1). The heavy metal composition of the Kolkata dust was compared with reported data for other cities. Enrichment factors of Pb and As were high. Multivariate statistical analysis of the heavy metals and analysis of lead isotopic ratios of the dust revealed a predominant anthropogenic influence in the contamination. The range of lead isotopic ratios found in the dust was between 0.8789 and 0.8998 with a mean Pb concentration of 383 mg kg?1. The three Pb isotope plots of street dust, diesel and rainwater clustered linearly, while coal did not fit into this trend. The highest 207/206 lead isotopic ratio obtained was from diesel with a mean value of 0.9015, followed by the rainwater sample. The application of the binary mixing model showed that about 66.86% of lead contamination in the street dust was sourced from the atmosphere. The two components extracted by the principal component analysis explained 64.34% of the total variance. Vehicular and industrial emissions appeared to be an important contributor to the accumulation of heavy metals in the dust. The health risk assessment study of the dust indicated carcinogenic risk associated with As and Cr.  相似文献   

11.
Road traffic accidents pose serious threats to human lives and often cause premature deaths, disabilities, and socioeconomic impacts. The objective of this study is to analyze the fatal road traffic accidents in Bangladesh by performing a space–time characterization of fatality rates involving an innovative newspaper-based method in concert with gridded population data to construct a road traffic fatality database. Kernel density estimation, temporal data plots and space–time pattern mining tools that combine the Getis-Ord Gi* statistic with the Mann–Kendall test are used to describe spatio-temporal hotspots/coldspots and trends. Results show different patterns between the urban and rural areas of Bangladesh and higher rates of road traffic accidents occur in the metropolitan regions (Dhaka) and in a northern region centered on Sirajganj area. Most of the road traffic accidents took place in between 9:00 and 12:00 pm while the accident rates remain low between 12:00 and 3:00 am. Spacetime analysis results reveal a core region of persistently high rates along with four smaller regions with high and intensifying rates. The output of this study could be useful to reduce road traffic fatalities, injuries, increase awareness, and adopt necessary interventions for public safety through integrating both the local, regional, and central level decision makers of public transportation policy and issues in Bangladesh. The approach has potential to be translated to other developing countries.  相似文献   

12.
Landslides frequently occur during large earthquakes and storms in Taiwan, supplying large volumes of sediment to downslope areas. When coupled with the intense northeast monsoon over Taiwan in the dry winter season, this can lead to high concentrations of airborne particulates that are hazardous to human health. Air quality monitoring stations near unvegetated riverbanks recorded high concentrations of particulate matter less than 10 μm (PM10) after Typhoon Morakot in 2009. The objective of this study was, therefore, to analyze the effects on air quality of sediment caused by the typhoon. A deflation module was simulated, and the resulting estimates were compared with observed data from the Taitung monitoring station for 2004 and 2005. The relationship of dust flux to average atmospheric dust concentration was analyzed for October to December 2001–2010. Analysis showed that the 2001–2008 data are highly correlated (0.78) with the average concentration. The intercept of 28.07 represented the background concentration with no dust emission, from October to December of 2001–2008. Based on the dust flux potential in 2009, the average yearly PM10 concentration would be 37.98 µg/m3; however, the measured concentration was 61.67 µg/m3 from October to December. This suggests the strong influence of dust re-suspended from unvegetated riverbanks by Typhoon Morakot.  相似文献   

13.
Daniali  Mohamad  Karimi  Neamat 《Natural Hazards》2019,97(1):259-281

Dust storms are yet quite frequent in various parts of the world, particularly ancient Mesopotamia (approximately corresponding to most parts of Iraq as well as certain surrounding regions toward its north). To add to the ongoing difficulty, monitoring dust patterns has been proven to be a rather difficult endeavor given the absence of reliable ground-based monitoring stations in the corresponding area. Additionally, western provinces of Iran, especially Khuzestan in the southwest of Iran, have been severely affected by dust storms carried by the westerly winds, blown through neighboring countries in ancient Mesopotamia. This study proceeds to employ aerosol optical depth (AOD), extracted from the MODerate-resolution Imaging Spectroradiometer onboard the Terra spacecraft, to assess spatial dust variations between 2001 and 2017 over the Khuzestan province and ancient Mesopotamia. The variations were also correlated with the temporal dust changes in the Khuzestan province. Frequency of occurrence for AOD?>?1 was used to identify and categorize major dust sources in the aforementioned regions. The findings were indicative of an increasing trend in the annual AODs of the Khuzestan province, which eventually led to a significant increase from 2008 toward the end of 2012, but decreased again in the following years. Correspondingly, the entire time period (2001–2017) was further divided into three sub-periods: the first time period spanning from 2001 to 2007, followed by the second from 2008 to 2012 and finally a third time period from 2013 to 2017. Dust source identification was speculative of numerous dust spots in Iraq, Syria, Kuwait and also the southern parts of Khuzestan province which have become more active in recent years. Additionally, a large active dust spot was pinpointed between the northwest Iraq and eastern Syria border which has become extremely active during the second time period, possibly due to a severe drought in the Fertile Crescent.

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14.
This paper examines the theory and supporting evidence for links between desertification, drought and dust storms with a particular focus on studies undertaken in and around the Gobi Desert. Overgrazing of rangeland by pastoralists has been the most commonly cited cause of desertification in global drylands for more than 30 years, but the evidence supporting this link is not always convincing. Nonetheless, overgrazing, desertification and dust storms are frequently connected, regardless. Drought is another well-known and important driver of vegetation cover change. Distinguishing between vegetation cover adversely affected by drought and that reduced by grazing is imperative for policy makers because identifying the incorrect driver of vegetation change risks the development of inappropriate policy.  相似文献   

15.
The increased numbers of vehicles using roads in the world today are cause of traffic-related problems, and in this respect, road traffic accidents are an important topic relating to public health. Especially on the road connecting two border provinces, traffic accidents are increasing substantially in parallel with the quantity of transport facilities. By determining areas where traffic accidents result in deaths or injuries, accident prevention strategies can be developed. This study applies the spatial statistics techniques using Geographical Information Systems (GIS) to determine the intensity of traffic accidents (hot-spot regions) over 45 km of main routes in Rize Province, Turkey. Traffic accidents recorded in data spanning 5 years are combined with a geographical dataset for evaluation using hot spot statistical analysis. Unlike other studies, this study used hot spot analysis based on network spatial weights (an innovative review in the methods of determining traffic accident hot spots: “novel application of GIScience”) to identify black spots for traffic safety. To perform the analysis using Hot Spot Analysis: Getis-Ord Gi*, a generated network dataset and the spatial weights of the road data are used to generate network spatial weights. Then, Kernel Density method is used to define traffic accident black spots. Finally, these two methods are compared each other with visually.  相似文献   

16.
Trends of shoreline changes need a scientific study as erosion affects the coastal ecosystem and environment. This study focuses on the trends of shoreline changes along the Van Island, Gulf of Mannar, during the period from 2000 to 2016 using the Digital Shoreline Analysis System model of a tool in Arc Map. Shorelines were extracted from the Landsat OLI and ETM+ satellite data from the years 2000, 2005, 2010 and 2015 and short-term changes obtained by TSS with the help of GPS. The rates of changes were calculated by the standard method of end point rate based on 157 transects lines and baseline. The average value of EPR observed was ?5.03 m/year during the study period. Statistics of EPR further calculated the average long-time intervals during the period of 15 years and also short-term changes. It is noted that the study area of Van Island’s degradation is very rapid. The analysis shows that the surveyed years from 2015 to 2016 record the highest erosion and retreat of shoreline changes in December 2014 to May2015 than in May2015 to December 2015. Based on the predicted EPR value of ?125 m/year of erosion in the next 25 years, it is concluded that the Van Island will vanish.  相似文献   

17.
Our main aim was to identify the impacts of natural (solar activity, geomagnetic disturbances) and man-made factors on suicides in northwestern Russia. Data on a total of 908 suicides in the town of Kirovsk (Murmansk oblast) were analyzed for the period from 1948 to 2010. The rates of suicides were analyzed with respect to seasons of the year. We have identified three maxima in the seasonal distribution of the number of suicides [March–May (P < 0.001), July (P = 0.006), October (P < 0.001)], which coincide with maxima in the distribution of the most intense (Ap > 150 nT) magnetic storms. Multi-taper method-spectrum analysis revealed periodicities (~9–10 and ~25 years) which may be related to the main cycles of solar activity. The periods of ~3.1–3.5 and ~2–2.3 years are probably the third and the fifth harmonics of 11-year solar cycle, respectively. These periods are correlating with similar periodic variations in geomagnetic aa-indexes and meteorological parameters. It was determined the statistically significant (r = 0.8; P = 0.005) relationship between suicide and Cu emissions from Cu–Ni smelters of Russian North for the period 1997–2009.  相似文献   

18.
In this research, the frequency of dust storms was prepared at 87 synoptic stations for the period of 1987–2013. These data were classified by means of Fuzzy c-means clustering algorithm. Satellite images of MODIS and brightness temperature index were also used for detection and tracking dust storm of 30 Jun 4 July 2008. The results indicated that Iran is classified in five clusters by the dust-storm-frequencies from which, cluster 5 is reclassified in three clusters because of its wide range. The maximum number of days with dust storms was observed in cluster 1 that includes only Zabol station with the frequency of 790 days with the duration 1987–2013. The minimum number of days with dust storms was observed in cluster 5-3 that includes the stations located in portions of North, Northwest, Northeast Iran and the higher elevations of the Zagros in western Iran. A case study about a severe dust storm in Iran using satellite images indicate that brightness temperature index (BTI) is a desired index for detection and monitoring of dust storms. The source of the investigated dust storms is Iraq and South of the Arabian Peninsula that had influenced the western half of Iran in several days. The frequency of dust storms increased markedly in the west, southwest of Iran and Persian Gulf around as main receptors from emerging dusty areas but it increased slightly in the eastern half of Iran.  相似文献   

19.

In this work, a dynamic GIS modeling approach is presented that incorporates: a) geoinformatic techniques, b) 55-year historical meteorological data, and c) field measurements, in order to estimate soil erosion risk in intensively cultivated regions. The proposed GIS-based modeling approach includes the estimation of soil erosion rates due to surface water flow under current and future climate change scenarios A2 and B1 for the years 2030 and 2050. The soil erosion was estimated using the Universal Soil Loss Equation (USLE). The proposed soil erosion model was validated using field measurements at different sites of the study area. The results show that an extended part of the study area is under intense erosion with the mean annual loss to be 4.85 t/ha year−1. Moreover, an increase in rainfall intensity, especially for scenario B1, can generate a significant increase (32.44 %) in soil loss for the year 2030 and a much more (50.77 %) for the year 2050 in comparison with the current conditions. Regarding the scenario A2, a slight decrease (1.85 %) in soil loss was observed for the year 2030, while for 2050 the results show an adequate increase (7.31 %) in comparison with the present. All these approaches were implemented at one of the most productive agricultural areas of Crete in Greece dominated by olive and citrus crops.

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20.
Kelman  I.  Gaillard  J. C.  Lewis  James  Mercer  Jessica 《Natural Hazards》2016,83(1):129-147
This paper calculated the embodied carbon in China export and its distribution in each industrial sector. The calculation results showed the total carbon emission of export experienced an increase before 2007 and then a decrease till 2010. The ratio of export embodied carbon accounting for the total carbon emission in China also increased from 31 % in 2002 to 52 % in 2007 and then declined to 40 % in 2010. As for distribution, the export embodied carbon emission of the following industries such as machinery and equipment manufacturing, metal products manufacturing industry, chemical industry, textile, clothing and leather products manufacturing industry ranked the highest. According to the calculation and analysis of the main driving factors of embodied carbon growth, we analyzed the structure effect, scale effect and technological effect’s influence on embodied carbon growth, respectively. We also calculated the trade competitiveness index of 17 export industries. Through research, we found that the products with strong international competitiveness belong to high-carbon-emission categories, which was the main reason of high carbon emission in China export. Finally, we proposed related policy suggestions to promote China’s export trade structural readjustment and optimization and China’s low carbon development in export.  相似文献   

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