United States federal law requires that construction sites obtain planning permissions to conduct earth moving and clearing of areas, so that plans to control dust emissions while the work is being carried out are specified. The most frequent dust control violations occur at new residential housing developments in urban areas. Most governmental Environmental Protection Agencies, including the United States Environmental Protection Agency (EPA) mandate that facilities that generate fugitive dust, minimize or mitigate the production of dust in their operation. Tarps and netting are often used to reduce the amount of dust released from construction sites. Recently, initiatives such as Project-Dust have been established to directly study dust in the Middle East. The amount of pollutants in the air has surpassed more than 50 times the normal level several times in a year. In the Khuzestan Province, it has led to the severe increase of air pollution. In Iran, the dust is already affecting more than 5 million people directly, and has emerged as a serious government issue in recent years. As a multi-factor phenomenon, there is not yet a clear consensus on the sources or potential solutions to the problem. Recently, because of climate change and the escalating process of desertification, the problem has worsened dramatically. Middle Eastĭust in the Middle East has been a historic phenomenon. Saharan dust, in particular, can be transported and deposited as far as the Caribbean and the Amazon basin, and may affect air temperatures, cause ocean cooling, and alter rainfall amounts. This airborne dust is considered an aerosol and once in the atmosphere, it can produce strong local radiative forcing. ĭust in the atmosphere is produced by saltation and abrasive sandblasting of sand-sized grains, and it is transported through the troposphere. One-third of the global land area is covered by dust-producing surfaces, made up of hyper-arid regions like the Sahara which covers 0.9 billion hectares, and drylands which occupy 5.2 billion hectares. This includes areas where grazing, ploughing, vehicle use, and other human behaviors have further destabilized the land, though not all source areas have been largely affected by anthropogenic impacts. Atmospheric or wind-borne fugitive dust, also known as aeolian dust, comes from arid and dry regions where high velocity winds are able to remove mostly silt-sized material, deflating susceptible surfaces.
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