Rainfall Projection Using Different Emission Scenarios for Two Climatic Normals in the Niger Delta Region of Nigeria (2016-2045 and 2045-2075)

This study projected rainfall using for two emission scenarios (A2-high emission and B2-low emission) and for four seasons (DJF, MAM, JJA and SON). The projection reveals that Yenagoa and Port Harcourt are areas that will have an increase in rainfall amounts of more than 10mm under A2 scenario in DJF within the first climate normal (2016-2045) and the increase is further expected to step up to above 12mm within the next climate normal (2045-2075) while under the B2 scenario the projection reveal a decline in rainfall amounts within Benin, Ogoja, Owerri, Ondo and Umudike within the first climate normal (2016-2045) while Ondo is projected to experience a decline within the next climate normal (2045-2075) in DJF. In MAM in both the first and second climate normals under the two emission scenarios (A2, B2), there is constant, steady, and significant increase in rainfall amounts over the region. More specifically, Warri, Calabar, Port Harcourt, Uyo and Yenagoa is projected to experience an increase in rainfall amounts of more than 20mm under the A2 scenario in the first and second climate normals while on the other hand, under the B2 scenario the projection reveal that an increase in rainfall amounts of more than 10mm will affect Warri, Calabar, Port Harcourt, Uyo, Owerri and Yenagoa in the second climate normals while all the cities are also affected except Owerri in the first climate normal. Generally, under emission scenarios, A2 and B2 only cities like Ikom, Ondo and Umudike are projected to have extremely low increase in rainfall amount within the MAM season of the climate normals. The Statistical Downscaling Model developed revealed increase in rainfall amounts within the projected period in the two climate normals with higher increase under A2 scenario than B2. The study recommends that it is necessary to develop a local climate management system in preparedness for climate change. Effort should be made to initiate and maintain the B2 scenario, intensification of public awareness campaign on coping and adaptation strategies to climate change

Keywords: Rainfall projection; Climate normal; Emission scenarios; Niger delta region