Atmospheric visibility trends in the Niger Delta Region Nigeria 1981-2012

Abstract

Atmospheric pollution has been serious in the Niger delta region, as the hub of oil production in Nigeria
due to the rapidly expanding economic and industrial activities which has significant impacts on
visibility. Visibility is a highly relevant factor indicating the level of air quality and inversely related to the
optical extinction coefficient caused by gas and particle phases. A 31 years Horizontal visibility data for
some coastal weather stations in the Niger delta region acquired from the Nigerian Meteorological
Agency (NIMET) Abuja Nigeria was analysed. In this study, atmospheric visibility trends for six Niger
delta cities (Akure, Warri, Owerri, Uyo, Calabar and Portharcourt) in Nigeria were evaluated for the period
1981-2012 using statistical techniques. It was observed that the yearly seasonal indices for the mean
visibilities for the stations, Warri, Owerri, Akure, Uyo, Calabar and Portharcourt are 2.056817, 1.523725,
0.988518,-3.87354, -0.08079, and -0.6144 km respectively. Akure, Owerri and Warri have experienced a
significant increase in visibility during the entire time series while for other three cities/stations Phc, Uyo
and Calabar shows decreasing visibility trends. The general dreadful conditions of visibility in these
cities were probably due to the excess aerosol loading, oil exploration and exploitation in the region
which leaves chunks of farmland, water bodies and the atmosphere severely polluted and degraded.
Therefore, an urgent targeted reduction of atmospheric pollution may be needed to better air quality in
the Niger delta region Nigeria.