The Thirty Years Trend Analysis of Harmattan Season Visibility and Temperature in Sahel Zone of Nigeria
Keywords:
Harmattan season, Sahel zone, Visibility, TemperatureAbstract
Climate anomalies have created short-duration climatic oscillations as against the normal cycle and this has posed and is still posing a threat to life and properties in Nigeria. A special climate change unit was created by Nigerian government in 2006 to address this problem. In this study, the meteorological data were obtained from National Oceanic Atmospheric Agency-National Climate Data Centre (NOAA-NCDC) for Sahel zone of Nigeria to analyse the long-term (1988-2017) trend and variability of visibility and temperature. The result reveals that visibility exhibited a decreasing trend while temperature shows an increasing trend over 30-years period. The 30-years seasonal mean visibility is 9.2±2.39, km while the corresponding temperature is 25.12±3.87oC respectively. Decade analysis revealed that the most obvious changes happen during the third decade. Standardize anomaly chart of visibility and temperature also reveal that changes in visibility and temperature are consistent over the study period. A simple regression analysis at p< 0.05 significant level were conducted with visibility as dependent and temperature as independent variables. The results show that the magnitude and nature of the relationship between temperature and visibility depend upon time. However, the trend line is consistently exponential. By dividing the data into ten years interval a much stronger and more significant relationship were obtained.
References
A. Oyem & A. Igbafe “Analysis of the atmospheric aerosol loading over Nigeria”, Environmental Research Journal 4 (2010) 145-156.
M. Balarabe, F. Tan, K. Abdullah & M. Nawawi “Temporal-spatial variability of seasonal aerosol index and visibility–A case study of
Nigeria”, Space Science and Communication (IconSpace), 2015 International Conference IEEE (2015) 459-464.
Atmospheric System Research (ASR) Funding Opportunity Number: DE-FOA-0001845 (2010) 1-22
A. C. Anuforom “Spatial distribution and temporal variability of Harmattan dust haze in sub-Sahel West Africa. Atmospheric Environment” 41 (2007) 9079-9090.
T. Chineke & I. Chiemeka “Harmattan Particulate Concentration and Health Impacts in Sub-Saharan Africa”, The African Review of Physics, (2010) 3-12.
S. Wolfgang & S. Brigitta “Meteorological causes of Harmattan dust in West Africa”, Geomophology 95 (2007) 412-428
M. Balarabe, K. Abdullah & M. Nawawi “Long-Term Trend and Seasonal Variability of Horizontal Visibility in Nigerian Troposphere”, Atmosphere 6 (2015) 1462-1486.
Y. J. Kaufman, D. Tanre & O Boucher “A satellite view of aerosols in the climate system”, Nature 419 (2002), 215223.
A. C. Anuforom, L. Akeh, P. Okeke & F. Opara "Inter-annual variability and long-term trend of UV-absorbing aerosols during
Harmattan season in sub-Saharan West Africa", Atmospheric Environment 41 (2007) 1550-1559.
K.O. Ogunjobi, A. Oluleye & V.O. Ajayi “A long-term record of aerosol index from TOMS observations and horizontal visibility in sub-Saharan West Africa”, International journal of remote sensing 33 (2012) 6076-6093.
Intergovernmental Panel on Climate Change IPCC United Nations Report, Nov. 1990, Geneva, Switzerland: WMO (1990).
C. B. Mabo “Temperature variation in northern Nigeria between 1970 and 2000”, J. Energy Environ 19 (2006) 80-88.
C. I. Ikhile “Impacts of Climate Variability and Change on the Hydrology and Water Resources of the Benin- Owena River Basin”, PhD Thesis, Unpublished. Benin City, Nigeria (2007) University of Benin,
E. Onyenechere “Climate change and spatial planning concerns in Nigeria: Remedial measures for more effective response”, Journal of Human Ecology 32 (2010) 137-148.
J. E. Imo & N. Ekpenyong “Extreme Climatic Variability in North-western Nigeria: An Analysis of Rainfall Trends and Patterns”, Journal of Geography and Geology 3 (2011) 51-62.
A. Karmalkar, C. Mcsweeney, M. New & G. Lizcano “UNDP climate change country profile for Nigeria”, Retrieved from http://countryprofile.geog.ox.ac.uk (2009)
A. L. Quijano, I. N. Sokolik & O.B. Toon “Influence of the aerosol vertical distribution on the retrievals of aerosol optical depth from satellite radiance measurements”, Geophysical Research Letters 27 (2000) 3457-3460.
IPCC, “Intergovernmental Panel on Climate Change, Global Climate Change and Rising Challenge of Sea”, Report of the Coastal Zone Management Subgroup, Supporting Document for IPCC - (1992a) Update Report
IPCC, “Intergovernmental Panel on Climate Change”, The Supplementary Report to the IPCC Impacts Assessment, WJ Target, In: Mc G, GW Sheldan, DC Griffith (Eds): Report prepared by IPCC Working Group II, Canberra: Australian Government Publishing Service (1992b).
N. M. Mahowald, C. S. Zender, C. Luo, D. Savoie, O. Torres & J. Del Corral “Understanding the 30year Barbados desert dust record", Journal of Geophysical Research: Atmospheres (19842012)”, 107 (2002) 7-16.
A. Goudie & N. Middleton “Saharan dust storms: nature and consequences", Earth-Science Reviews, 56 (2001) 179-204.
D. Junjun, X. Zhenyu, Z. Bingliang & D. Ke “Comparative study on long-term visibility trend and its affecting factors on both sides of the Taiwan”, Strait. Atmos. Res. 143 (2014) 266-278
R. L. Miller & I. Tegen Climate response to soil dust aerosols. Journal of Climate 11 (1998) 32473267.
A. Usman, K. O. Olaore & G. S. Ismaila, “Estimating visibility using some Meteorological data at Sokoto, Nigeria”. International Journal of Basic and Applied Sciences 1 (2013) 810-815
W. M. To “Association between energy use and poor visibility in Hong Kong SAR”, China Energy 68 (2014 ) 12-20
