Insights into increasing land subsidence along Nigeria’s Gulf coast

Abstract Land subsidence is a threat to environmental sustainability and can pose greater dangers with a proportionate rise in bordering sea levels. Nigerian low-lying coastal region and the various economic activities around the coast are vulnerable to rising sea level because of global warming. However, no existing study has examined sea-level rise combined with land subsidence. This study reviews available literature on land subsidence and consequential relative sea-level rise along Nigerian coastlines and identifies research gaps. Subsidence occurs, at least, in four Nigerian coastal cities – Lagos, Port Harcourt, Uyo, and Warri. The highest observed subsidence (up to 520 mm/year) is found in the Harcourt area, which is likely due to continued groundwater pumping and oil and gas extraction.