On the characteristics of sea breezes over Nigerian coastal region

Abstract

This paper describes the characteristics of sea breezes over the coastal region of Nigeria. While considerable attention has been paid to monsoon circulation over this coastal region, there is virtually no information in literature on sea breezes over the region. This study analyzed 5 years (1979–1983) data of hourly temperature and wind speed and direction from four coastal stations in Nigerian—Lagos, Warri, Port-Harcourt, and Calabar—in order to examine the characteristics of the sea breeze in the region. The results show that sea breeze usually started between 1000 and 1200 UTC, attained maximum strength of about 2–5 m s−1 in the afternoon around 1500–1600 UTC and subsided between 2000 and 2200 UTC. Consistent with maxima temperature contrast between land and sea, the maximum frequency of sea breeze occurs in February–May and September–November, with duration of about 11–13 h. The diurnal variation of wind vectors with time, portrayed by means of hodograph, shows that sea breeze rotates clockwise and anticlockwise over the region. We found that only the stations adjacent to bay demonstrate clockwise rotation during the day.