Description
ABSTRACT
The information on the variability of rainfall is very essential for general planning. Rainfall data in three stations (A, B and C); Institute of Agricultural Research (IAR), Nigerian College of Aviation Technology (NCAT) and Federal College of Education (FCE), were statistically analysed in assessing the spatial distribution of rainfall within southern Kaduna. Weekly rainfall data analysis observed in the stations simply depicts that weeks 33 and 34 (both in August) have the highest amount of rainfall with station B having the least overall mean weekly rainfall. Monthly rainfall data analysis reveals the month of August receiving the highest amount of rainfall while annual rainfall analysis revealed that, despite their proximity, IAR and Aviation have different years of maximum and minimum rainfall amounts received during the period of the study. They show greater similarity than when compared with the FCE weather station. This situation may be attributed to their proximity. The analysis of variance however confirms that there is no significant difference among the rainfall data of the weather stations.
TABLE OF CONTENTS
COVER PAGE
TITLE PAGE
APPROVAL PAGE
DEDICATION
ACKNOWELDGEMENT
ABSTRACT
CHAPTER ONE
1.0 INTRODUCTION
- BACKGROUND OF THE PROJECT
- PROBLEM STATEMENT
- AIM OF THE STUDY
- SCOPE OF THE STUDY
- SIGNIFICANCE OF THE STUDY
- PROJECT ORGANISATION
CHAPTER TWO
LITERATURE REVIEW
- REVIEW OF AVERAGE WEATHER IN KADUNA
- REVIEW OF THE STUDY
- THE EFFECTS OF WEATHER ON AGRICULTURE
CHAPTER THREE
METHODOLOGY
- STUDY AREA
- SOURCE OF DATA
- METHODS OF ANALYSIS
CHAPTER FOUR
- RESULT ANALYSIS
- ANALYSIS OF RAINFALL DATA IN THE DIFFERENT WEATHER STATIONS
- RAINFALL VARIATION ANALYSIS FOR THE THREE STATIONS
CHAPTER FIVE
CONCLUSION, RECOMMENDATION AND REFERENCES
- CONCLUSION
- RECOMMENDATION
- REFERENCES
CHAPTER ONE
1.0 INTRODUCTION
1.1 BACKGROUND OF THE STUDY
Rainfall is an important aspect in both climatic and geomorphologic studies. Amount of rainfall in a given region is influenced by many factors; among them are relief, wind and direction (relative to coastal orientation) and distance from the ocean. For instance, where humid air masses move across a region are forced to rise over highlands/plateau tend to bring about instability resulting in heavy rainfall (Ayoade, 1983).
The geographical location of Nigeria, its topographical variations and latitudinal extent dictate the behaviour of the climatic types and its characteristics in the region. Rainfall in Nigeria is the most variable climatic element both in its spatial and temporal distribution as a real precipitations which is the average depth of precipitation over a specific area calculated on timescales on a storm, seasonal, or annual basis vary from place to place in the country. Recent short-term climatic variability and most particularly rainfall fluctuations are becoming increasingly of concern to the government and the people. This is because rainfall variability determines the planning horizons of agriculture, water resources and many government and judicial processes. (Ayoade, 1983; Olaniran and Summer, 1989).
Various aspects of the rainfall of Nigeria have been studied based on daily, weekly, monthly and annual rainfall values. These include the onset, advance, retreat, normality, trends and periodicities of rainfall (Ilesanmi (1972); Kowal (1972); Ayoade (1983); Adefolalu (1986);; Oladipo (1989); Olaniran and Summer (1989); Anyandike (1993); Folorunsho (1997); Yusuf (1999); Sawa (2002); Yusuf and Atteh (2009)). These knowledge of variability, annual rainfall trends and periodicities have helped in predicting future incidents and probability of rainfall in Nigeria.
For example, Ilesanmi (1972) observed in southern Nigeria that at the onset and end of rainy season, the rains are in the form of heavy showers of short duration, staring with a maximum intensity of upto 75mm/hour and more, declining the intensity after about 30 minutes when the storm gives way to a steady downpour with a lower intensity of about 12.5mm/hour and less.
The amount of rainfall has also been shown to be at variance with intensity. For instance, Ayoade (1983) found that rainfall intensity is not associated with amount or number of raindrop size. The intensity and time period of the rainfall event determines the amount of rainfall in an area at a time and the average amount of rainfall in an area over years sums up to the mean annual rainfall of the area. Also with the spread of rainfall characteristics, the productivity of the area may be determined.
The nature of rainfall over northern Nigeria is highly variable and the variability includes rainfall amount, time and duration, intensities and spatial coverage. Adejuwon et al (1989) demonstrated that variabilities are observed in amounts and spatial coverage; in fact it is also eminent in the seasonal characteristics in term of onset and end of rainy season occurrence of cloud burst or long dry spell. The fact is that, for a particular period, the rainfall may be above average at a place and below average at another. Similar observations have been made by Oladipo (1989) and Sawa (2002).
The great deal of research into rainfall variability has emphasized the spatial characterization on different temporal scale and the “meso-scale” has received considerable attention. It is however noted that there is still some gaps between stochastic description of temporal and spatial variation of rainfall and also the understanding of physical mechanism that cover this variability at smaller scale in areal precipitation analysis. Understanding of the amount of rainfall and how it varies from point to point within smaller areas therefore becomes imperative.
In this study an attempt is made to provide more information on the spatial distribution of rainfall amount in southern Kaduna, by establishing the spatial distribution of weather stations in the city, collecting rainfall data from the different weather stations, analysing the rainfall amounts for the different weather stations and assessing their spatial distribution.
1.2 PROBLEM STATEMENT
Growing season can be defined as the period of the year during which rainfall distribution characteristics are suitable for crop germination, establishment, and full development. It is the period of the year categorized as the rainy or wet season, the length of which varies spatially, temporally, and with crop type.
In a typical tropical country like Nigeria, rain falls in different months of the year at different places, as the rain belt appears to follow the relative northward and southward movements of the sun. In this tropical situation of a marked seasonal rainfall regime, variability of the onset and retreat of rain is highly significant, and its estimation and prediction are necessary. A delay of 1 or 2 weeks in the onset is sufficient to destroy the hopes of a normal harvest. A false start of planting, encouraged by a false start of rainfall, may be followed by prolonged dry spells whose duration of 2 weeks or more may be critical to plant germination and/or growth. For instance, in 1973, the onset was earlier in Nigeria, which encouraged early planting and animal migration. However, this was a false onset, resulting in both crop and animal loss. Also, according to Odumodu (1983), greater variability is experienced at the onset and retreat of rainfall than in the mid-season. Particularly notorious in this regard is the onset, as it is usually foreshadowed by a succession of isolated showers of uncertain intensity accompanied by dry periods of varying duration.
1.3 AIM OF THE STUDY
The main aim of this work is to provide more information on the spatial distribution of rainfall amount in southern Nigeria, by establishing the spatial distribution of weather stations in the city, collecting rainfall data from the different weather stations from southern Kaduna.
1.4 SCOPE OF THE STUDY
This study examines the length of the growing season in Nigeria using the daily rainfall data of southern Kaduna. The data were collected from the archives of the Nigerian Meteorological Services, southern Kaduna. The length of the growing season was determined using the cumulative percentage mean rainfall and daily rainfall probability methods.
1.5 SIGNIFICANCE OF THE STUDY
As a student of this institution, this study made me to understand how variation of rainfall seasons affects farmers and their harvest. This study also exposes me to the effect of dry season on crops.
1.6 PROJECT ORGANISATION
The work is organized as follows: chapter one discuses the introductory part of the work, chapter two presents the literature review of the study, chapter three describes the methods applied, chapter four discusses the results of the work, chapter five summarizes the research outcomes and the recommendations.
Reviews
There are no reviews yet.