5,000.00 3,000.00





This study examines the effect of Atlantic Sea Surface Temperature on rainfall in some selected coastal stations in Nigeria for a period of 10 years (1991 – 2000). Correlation between rainfall and Atlantic SST of  the coastal stations and to determine the trend of Atlantic SST and rainfall of the coastal stations over the 10 years period (1991 – 2000) were determined. Sea Surface Temperature and monthly rainfall data were used for this study. The Atlantic SST covers 10 years spanning between 1991 – 2000 was made available by the European Centre for Medium Weather Forecasting (ECMWF) and the rainfall data for Ikeja and Calabar  used for this study were collected from Nigerian Meteorological Agency (NIMET) and Ondo (Okitipupa) State was made available By Climate Research Unit (CRU). Statistical analysis which include mean, standard deviation, trend analysis and correlation analysis were carried out. The rainfall and SST data were standardized to reduce problems inherent in the analysis of rainfall: the highly diverse means and variances and the randomness of the convective process reflected in individual station. The result showed that Atlantic SST has a little role to play in determining the rainfall of the coastal states. The trend of Atlantic SST was found to be increasing while the rainfall trend in Ikeja and Okitipupa was decreasing and that of Calabar was increasing. The correlation coefficient (R2) of Atlantic SST against Ikeja is 0.119 while that of Atlantic SST against Okitipupa is 0.018 and that of Atlantic SST against Calabar is 0.014. This result which shows that there is no significant correlation between the Atlantic SST and the coastal stations and that Atlantic SST has little or no effect on Rainfall in these coastal stations.













I dedicate this Project work to God the Almighty and to the benefit of Mankind, for giving me the privilege and opportunity to complete this research work.





                My gratitude goes to God for his grace, mercies, protection, provision and love that saw me through the course of my 5 years programme in FUTA. All glory and adoration to be unto him alone.


                My special thanks goes to my father Mr. Wilson Adebayo who lead me in the way of education and also my variable mother Mrs. Wilson Gbeminiyi for her support. This will not be completed without extending my sincere thanks to my Grandmother for her immense contribution to my success in the area of finance and motherly care.


                My undiluted gratitude goes to my able supervisor, an academic titan, astute researcher, DR. A.Akinbobola for taking time off his tight schedule to proofread and mend my shortcomings during the course of this project work.


                I also appreciate and acknowledge DR. K.P Menang for his contributions and the knowledge imparted in me. I will also like to record a special thanks to my Head of  Department, DR M.I Oladapo and also appreciate the contributions of all lecturers in the Department of Marine Science and Technology.


                I will also like to thank the Nigerian Meteorological agency (NIMET), Climate Research Unit (CRU) and European Centre for Medium and Weather Forecasting (ECMWF) for dishing out their data.


                Finally, to my entire course mates and well-wishers, for making my program in FUTA a pleasant experience and fun filled, I say thank you so much.


God bless you all.









Table of Contents

COVER PAGE……………………………………………………………………………………………..i


ABSTRACT                      iii

DEDICATION                   iv

ACKNOWLEDGEMENTS                 v

TABLE OF CONTENTS                     vi

LIST OF FIGURES       viii

LIST OF TABLES          x


INTRODUCTION           1

1.1                 BACKGROUND OF STUDY           1

1.2                  AIM AND OBJECTIVES                   2

1.2.1              AIM:             2

1.2.2             OBJECTIVES:                 2

1.3                  STUDY AREA                 3

1.3.1              LOCATION                        3


2.0                  LITERATURE REVIEW                      7


3.0                  METHODOLOGY         10



3.2.1              STANDARDIZED ANOMALIES FOR RAINFALL                10

3.2.2              SEA SURFACE TEMPERATURE  11

CHAPTER FOUR          12

4.0                 RESULTS AND DISCUSSION        12


5.1                  SUMMARY                       34

5.2                 CONCLUSION                34

5.3                  RECOMMENDATION 35




























Fig 1: Map of Nigeria showing Lagos, Calabar & Ondo the coastal stations used for this study

Fig 2: Map of Nigeria showing the three coastal states used for this study

Fig.3: Showing the location where the SST data was acquired along the Nigeria coast

Fig 4: Annual variation of Sea Surface Temperature at 0000hrs

Fig 5: Annual variation of Sea Surface Temperature at 0600hrs

Fig 6: Annual variation of Sea Surface Temperature at 1200hrs

Fig 7: Annual variation of Sea Surface Temperature at 1800hrs

Fig 8: Monthly variation of Sea Surface Temperature at 0000hrs

Fig 9: Monthly variation of Sea Surface Temperature at 0600hrs

Fig 10: Monthly variation of Sea Surface Temperature at 1200hrs

Fig 11: Monthly variation of Sea Surface Temperature at 1800hrs

Fig 12: Over all monthly variation of Atlantic Sea Surface Temperature

Fig 13: Annual variation of Sea Surface Temperature over the decade (1991-2000)

Fig 14: Annual rainfall variation of Calabar over a decade (1991 – 2000)

Fig 15: Annual rainfall variation of Ikeja over a decade (1991 – 2000)

Fig 16: Annual variation of rainfall (mm) of Okitipupa over a decade (1991-2000)

Fig 17: Monthly variation of rainfall (mm) of Calabar

Fig 18: Monthly variation of rainfall (mm) of Ikeja

Fig 19: Monthly variation of rainfall (mm) of Okitipupa

Fig 20: Atlantic Sea Surface Temperature trend over the 10 years

Fig 21: Rainfall trend of Ikeja (1991 – 2000)

Fig 22: Rainfall trend of Calabar (1991 – 2000)

Fig 23: Rainfall trend of Okitipupa (1991-2000)

Fig 24: Standardized anomaly graph of Atlantic Sea Surface Temperature

Fig 25: Standardized rainfall anomaly graph of Calabar

Fig 26: Standardized rainfall anomaly of Ikeja

Fig 27: Standardized rainfall anomaly of Okitipupa

Fig 28: Relationship between Atlantic Sea Surface Temperature & rainfall in Ikeja

Fig 29: Relationship between Atlantic Sea Surface Temperature & rainfall in Calabar

Fig 30: Relationship between Atlantic Sea Surface Temperature & rainfall in Okitipupa





















Table 1.0: Showing above, below and within normal rainfall years

Table 2.0: Showing the correlation co efficient (R2) of Atlantic SST over the coastal stations

Table 3.0: Showing monthly average for Sea Surface Temperature


























1.1            BACKGROUND OF STUDY


The Oceans play an important role in the climate system owing in part to their large heat-storage capacity. The Oceans’ thermal inertia is communicated to the atmosphere via turbulent and radiative energy exchange at the sea surface. These energy fluxes in turn depend on a single oceanic quantity, the sea surface temperature (SST), as well as several atmospheric parameters including wind speed, air temperature, humidity, and cloudiness. SSTs thus play a key role in regulating climate and its variability. In particular, slow variations in SST provide a source of potential predictability for climate fluctuations on timescales of seasons and longer.


SST, which is the temperature of the water at the ocean surface, is an important attribute of the world’s oceans. The primary cause of rising sea surface temperature levels worldwide is climate warming due largely to excessive amounts of greenhouse gases being released into the atmosphere. The surface temperature of the world’s ocean varies with latitude, with the warmest waters generally near the equator and the coldest waters in the Arctic and Antarctic regions. As the ocean absorbs more heat, SSTs Sea will increase and the ocean circulation patterns that transport warm and cold water around the globe may change. Warm sea surface temperatures are known to be a cause of tropical cyclogenesis, cyclogenesis which is the development and strengthening of a tropical cyclone in the atmosphere, it involves the development of a warm-core cyclone due to significant convection in a favorable atmospheric environment over the earths’ ocean. Also coastal sea surface temperature can cause offshore winds to generate upwelling of nutrient-rich water towards the ocean surface, which can significantly cool or warm nearby landmasses.


Sea Surface Temperature (SST) plays a key role in the control of climate due to the processes in the control of climate due to the processes of evaporation, precipitation and atmospheric heating. Anomalies in the atmospheric variables are often associated to Sea Surface Temperature Anomalies (SSTA), at least a monthly or seasonal time scale. Due to the high inertia of the sea, SSTA is a reliable variable to be used as a climatic predictor.


Changes in SST can alter marine ecosystem in several ways. For example, variations in ocean temperature can affect what species of plants and animals are present in a location, alter migration and breeding patterns, threaten sensitive ocean life such as corals, and change the frequency and intensity of harmful algae blooms.


Because the oceans continuously interact with the atmosphere, SST can also have profound effects on global climate. Based on increases in sea surface temperature, the amount of atmospheric water vapour over the oceans is estimated to have increased about 5 percent during the 20th century. This water vapour feeds weather systems that produce precipitation, increasing the risk of heavy rainfall and snow. Changes in sea surface temperature can also shift storm tracks, potentially contributing to droughts in some areas.


The importance of SST cannot be over overemphasized in the field of Marine Science and Technology; it has diverse uses ranging from forecasting of weather such as development of showers, thunderstorm, fog and rainfall amount. SST may also determine areas of fish catchment by fishing fleet.



1.2           AIM AND OBJECTIVES

1.2.1         AIM:

The aim of this study is to analyze the effect of the Atlantic Sea Surface Temperature on seasonal rainfall in some selected coastal cities in Nigeria from year 1991 to year 2000. This study seeks to investigate the relationship between SST and rainfall in some of coastal cities in Nigeria.

1.2.2         OBJECTIVES:

The objectives of this project are to:


  • To understand how the seasonal rainfall in three coastal cities in Nigeria have changed over a 10 years period.
  • To understand how Sea Surface Temperature along the coast of Nigeria has changed over a period of 10years.
  • To study the correlation between Sea Surface Temperature and seasonal rainfall in the three coastal cities in Nigeria.

1.3            STUDY AREA

1.3.1         LOCATION


Three coastal state in Nigeria was used for this study and they include; Lagos State, Cross river State and Ondo State.


Nigeria with latitude 9.08200 N and longitude 8.67530E, is a country in West Africa. Nigeria shares land borders with the Republic of Benin in the West, Chad and Cameroon in the East, and Niger in the north. Its coast lies on the gulf of guinea in the south and it borders Lake Chad to the northeast.


The total area of Nigeria is 923,768 km2, while 910,768 km2 accounts for land and 1300 km2 accounts for places covered with water. Nigeria’s total boundaries are 4047 km, the border with Benin is 773 km that with Cameroon is 1690 km, Chad’s is 87 km and Niger is 1,497 km. Nigeria’s coastline is 853 km, Nigeria is a tropical country featuring tropical type of climate where seasons are damp and very humid. The seasonal pattern of climatic conditions over Nigeria gives the rise to four seasons in the south and two in the north. Southern Nigeria: (i) The Long Rainy Season (ii) The Short Dry Season (iii) The Short Rainy Season (iv) The Long Dry Season, Northern Nigeria: (i) The Long Dry Season (ii) The Wet Season Nigeria. These climate types are distinguishable as one move from the southern part of Nigeria to the northern part of Nigeria through Nigeria’s middle belt.


Nigeria is a maritime state with a coastline of approximately 853km and lies between latitude 4010’ to 140N and longitude 2045’ to 805’E. The Nigerian coastline stretches from the western border with the Republic of Benin to the eastern border with the Cameroun Republic. SST was taken along the coastline of Nigeria.


Lagos State with Coordinates 6035’N (latitude) 3045’E (longitude) is a state located in the southwestern geopolitical zone of Nigeria. Lagos State is arguably the most economically important state of the country. On the North and East it is bounded by Ogun state. In the west it shares boundaries with the Republic of Benin, behind its southern borders lies the Atlantic Ocean and has a total area of 3,577 km2.


Ondo State with Coordinates 7010’N (latitude) 5005’E (longitude) is a state in Nigeria created on 3 February 1976 from the Western State. It originally included what is now called Ekiti State, which was split off in1996. Akure is the state’s capital, the total area of Ondo state is 15,500 km2.


Cross River State with Coordinates 5045’N (latitude) 8030’E (longitude). It is a state in South South Nigeria, bordering Cameroon to the east. Its capital is Calabar with the state having a total Area of 20,156 km2.