An Investigation on Effects of Harmattan Dust (aerosols) on Horizontal Visibility Deterioration over Bauchi, North- eastern Nigeria
سال انتشار: 1393
نوع سند: مقاله ژورنالی
زبان: انگلیسی
مشاهده: 340
فایل این مقاله در 6 صفحه با فرمت PDF قابل دریافت می باشد
- صدور گواهی نمایه سازی
- من نویسنده این مقاله هستم
استخراج به نرم افزارهای پژوهشی:
شناسه ملی سند علمی:
JR_IJEE-6-2_003
تاریخ نمایه سازی: 7 آذر 1394
چکیده مقاله:
In this paper, the effects of harmattan dust (aerosols) on visibility deterioration over Bauchi, a town in North-eastern Nigeria was investigated. The data of visibility readings for a period of ten (10) years were obtained by human identification of target objects and landmarks, most especially hills and buildings at known distances in a full 360 degrees circle around the observation point. The annual cycles of visibility in Bauchi for daily and monthly averages for ten years (1998-2007) were obtained. This enabled us to determine atmospheric extinction coefficient (βext.), which results in the scattering and absorption due to dust particles by using the Koschmieder relationship for the study area. Bauchi recorded a maximum visibility value of about 35000.0m in April/May 2005. The minimum visibility value of nearly zero was recorded on November/December 2000. However, during the months of June-September, the maximum atmospheric extinction coefficient value of 0.230 was recorded in 2007 and the minimum atmospheric extinction coefficient value of 0.164 was recorded in 1999. For the months of harmattan season (November to February), the maximum atmospheric extinction coefficient value of 0.689 was recorded in 2000/2001 and the minimum atmospheric extinction coefficient value of 0.270 was recorded in 2005/2006.
کلیدواژه ها:
نویسندگان
F.O Anjorin
Department of Science Laboratory Technology, University of Jos. Plateau State. Nigeria
E.U Utah
Department of Physics, University of Uyo, Uyo. Akwa Ibom State. Nigeria
D Buba
Department of PRE- ND, Federal Polytechnic, Bauchi. Bauchi State. Nigeria