A dense cloud of dust swept across southern Afghanistan and Pakistan on December 20, 2011. When the Moderate Resolution Imaging Spectroradiometer (MODIS) took this image from the Terra satellite at 10:45 a.m., the dust was largely hemmed in by the Makran and Sulaiman Ranges in Pakistan with only a few wisps reaching south over the Arabian Sea. By the time Aqua MODIS flew over just three hours later, the storm had reached the coast. The dust storm continued on December 21.
The storm is being propelled by strong winds from the north. The winds picked up dust from dry lakebeds in the Hamun wetlands, on the border between Afghanistan and Iran. Concentrated plumes of dust rise from the pale wetlands to become a more diffuse cloud in the south and east. Dry lakebeds and wetlands are among the most common sources of dust in the world.
Dust storms can happen any time of the year in Afghanistan. On average, Afghanistan experiences blowing dust one to two days per month in the winter and six days per month at the height of the summer. Zabon, an Iranian city located near the border in the Hamun wetlands, reports 81 dust storms per year.
Blowing dust poses a hazard to transportation, as low visibility closes roads and airports. This particular storm prevented British Prime Minister David Cameron from visiting a British military base because the runway was closed for low visibility.
1. References
2. National Climate Data Center. (2008, August 20). Climate of Afghanistan. National Oceanic and Atmospheric Administration. Accessed December 21, 2011.
3. Prospero, J, Ginoux, P., Torres, O., Nicholson, S.E., and Gill, T.E. (2002, February). Environmental characterization of global sources of atmospheric soil dust identified with the Nimbus 7 Total Ozone Mapping Spectrometer (TOMS) absorbing aerosol product. Reviews of Geophysics, 40 (1).
4. Watt, N. (2011, December 20). Dust storm forces Cameron to abandon visit to Cam Bastion in Afghanistan. The Guardian. Accessed December 21, 2011.
NASA image courtesy Jeff Schmaltz, LANCE/EOSDIS MODIS Rapid Response Team at NASA GSFC. Caption by Holli Riebeek.
Instrument:
Terra - MODIS
توفان در افغانستان
گرد و غبار از بستر خشک دریاچه ی هامون بر خاست ، و ابری ضخیم را در جنوب و خاور افغانستان در آسمان گسترد .
توفان گرد و غبار در هر زمانی در افغانستان بر می خیزد . شواهد نشان از یک یا دو روز توفانی در ماه در فصل زمستان ، و شش روز در گرمترین روز های تابستان است .
شهر زابل در کناره ی دریاچه ی خشک هامون ، بر پایه ی گزارش ها، هر سا له حدود هشتاد و یک روز توفانی است .
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