TIME SERIES ANALYSIS MODELLING ON RAINFALL

Title Page

CHAPTER ONE

CHAPTER TWO

CHAPTER THREE

METHODOLOGY

CHAPTER FOUR

DATA PRESENTATION AND ANALYSIS

CHAPTER FIVE

SUMMARY, CONCLUSION AND RECOMMENDATIONS

Rainfall dynamics have been used as representative in the study of climate change and variability (Kusangaya et al., 2014; Mohammed et al., 2015), particularly in drier areas. Besides rainfall variability, temperature fluctuation and increased manifestation of extreme weather events such as heavy storms, droughts and floods were mentioned as basic features of climate variability (Ogungbenro and Morakinyo 2014; Suleiman and Ifabiyi 2015). Although variability is an inherent behaviour of climate, the increase fluctuation of climatic variables particularly rainfall is becoming a major concern and is associated to motivated rise in greenhouse gas (GHG) concentrations and the changes in land uses (Warburton et al., 2005; Reason 2007), which consequently intensified global warming and the hydrological cycle (Huntington 2006; Pachauri et al., 2014). In the semi-arid region of Nigeria due to its sensitivity to minor climatic changes, rainfall irregularities was found to aggravate the already existing environmental deprivation and water scarcity (Ogungbenro and Morakinyo 2014; Balogun et al., 2016). Consequently, there is increasing fear of food insecurity, human health challenges and slowing down of environmental flow (Balogun et al., 2016) and of course conflict over available natural resources particularly the water(Roma 2008; Audu 2013; Umar and Ankidawa 2016) Thus, the study area is prone to extreme weather events largely due to rainfall variability, and therefore farming and water supply in the area is subjected to the tyranny of climate variability, particularly the rainfall irregularities. Considering the importance of rainfall to agriculture and water supply in particular and to all aspects of human existence in Jigawa, the need to understand the nature and pattern of rainfall irregularities from trends and variations of the rainfall series has arisen.

There is now scientific consensus that global climate is changing (Kandnji, Verchot and Mackensen, 2006). Observation shows that as climate changes, changes are occurring in the amount, intensity, frequency and type of precipitation. These aspects of precipitation generally exhibit large natural variability, and El Nino and changes in atmospheric circulation patterns such as the North Atlantic Oscillation have a substantial influence, Mcilveen, (1992), Udo, et al., (2002) & Ryan, (2005). Pronounce long-term trends from 1990 to 2005 have been observed in precipitation amount in some places. Significantly wetter in eastern North and south American, Northern Europe and central Asia, but drier in Sahel, southern Africa, The Mediterranean and southern Asia (Trenbert et al. 2007). Africa is already a continent under pressure from climate stresses and is highly vulnerable to the impacts of climate change. Floods and droughts can occur in the same area within months of each other (UNFCCC, 2007). Climate change is a serious threat to poverty eradication and sustainable development in Nigeria. This is because the country has a large rural population directly depending on climate sensitive economic and development sector and natural resources for their subsistence and livelihood, Oladipo, (2008) & Osang et al (2013). Generally, the study of weather and climatic elements of a region is vital for sustainable development of agriculture, and planning. Particularly, rainfall and temperature temporal are deemed necessary as such can indirectly furnish the ―health‖ status of an environment. Extreme weather events that can lead to drought and prolonged heat spell, flooding etc  can assess through the statistical analysis of a regions temporal rainfall region. Rainfall variability is of climatologic interests, because it allows an evaluation of the magnitude of the departure of an individual year from the long-term mean and thus the frequency of extreme event persistence in departure patterns, trends in climate series, spatial pattern of variability and comparison with departure series for other climate indices. Climate is therefore the enduring regime of the atmosphere. To specify climate, the day to day values of weather elements are collected and averaged over a suitable period or time scale. The idea behind the ―average‖ weather‖ is that, a long term series of observation of weather element would produce an average (Normal) value to which each element would always tend to return, Lamb (1968), & Osang et al (2013). Normal climate is the arithmetic average of climatic element such as temperature, rainfall, wind, relative humidity etc, over a prescribed 30year interval. The 30year interval was selected by international agreement, base on the recommendation of the international meteorological conference in warsaw in 1933. This period is long enough to filter out the short term inter-annual fluctuations and anomalies, but sufficiently short so as to be use to reflect longer term climatic trends, (www.aos.wisc.edu|nsco|normals.html). This variability can be used therefore to calculate rainfall probabilities and the likely occurrence of period of rainfall shortage often referred to as drought or excess rainfall often referred to as flood. The degree to which rainfall amounts vary across an area or through time is an important characteristic of the climate of an area. The subject area in meteorology or climatology is called ‖rainfall variability‖. There are two types (or components) of rainfall variability, areal and temporal. The study of the latter is important in understanding climate change. The variation of rainfall amounts at various locations across a region for a specific time interval is termed Areal variability (time does not vary). While the variation of rainfall amounts at a given location across a time interval is temporal variability (area does not vary), Osang et al (2013) & Trenbert et al. (2007).

In Jigawa State a total of 18 out of 27 Local Government Areas have been more effect, with Gwaram, Birnin Kudu, Kirikasamma, Hadejia and Gumel are the worst hit. Wide swaths of farmland have been washes away with a loosed of farmland, crops, settlement and amounting of billions of naira.

 Heavy rainfalls or rain are likely to cause flooding in the Senatorial zones that leads collapse of many settlements and farmland as result of an excessive in Jigawa State.

The aim of this research is to analyze data on annual rainfall for 2000 to 2020.

The data that will be adopted in this research is the annual rainfall for the three senatorial zone in Jigawa State from 2000 to 2020. The data will be collected from Jigawa State Agricultural Rural Development Authority (JARDA).

This Study have shown that, some parts of Nigeria have been experiencing increase in the amount of rainfall over the years especially of recent. There are periods of extreme rainfall and also periods of less rainfall, thus leaving many with the fear of experiencing flood or drought. Since most of the studies on the variable (rainfall), by researchers have shown how possibly one can delineate periods of likely occurrence of flood or drought, there may be a limited empirical literature connecting the variables in most parts of the country. This study is to fill the gap on the subject matter. The study is also significant in determining the projected values of annual rainfall to enable one have knowledge of the future.

Rainfall: Rainfall is a major component of the water cycle and is responsible for depositing most of the fresh water on the Earth. It provides suitable conditions for many types of ecosystems, as well as water for hydroelectric power plants and crop irrigation

Drought: a drought is a period of time when an area or region experiences below-normal precipitation. The lack of adequate precipitation, either rain or snow, can cause reduced soil moisture or groundwater, diminished stream flow, crop damage, and a general water shortage

Flood: A flood is an overflow of water that submerges land that is usually dry. Floods are an area of study in the discipline of hydrology. They are the most common and widespread natural severe weather event. Floods can look very different because flooding covers anything from a few inches of water to several feet.

Flooding: Flooding is an overflowing of water onto land that is normally dry. Floods can happen during heavy rains, when ocean waves come on shore, when snow melts quickly, or when dams or levees break. Damaging flooding may happen with only a few inches of water, or it may cover a house to the rooftop.

Modelling: the act, art, or profession of a person who models. the process of producing sculptured form with some plastic material, as clay. the technique of rendering the illusion of volume on a two-dimensional surface by shading. the treatment of volume, as the turning of a form, in sculpture.

Metrology: is defined by the International Bureau of Weights and Measures (BIPM) as "the science of measurement, embracing both experimental and theoretical determinations at any level of uncertainty in any field of science and technology". It establishes a common understanding of units, crucial to human activity.

Climate: is the average weather in a given area over a longer period of time. A description of a climate includes information on, e.g. the average temperature in different seasons, rainfall, and sunshine. Also a description of the (chance of) extremes is often included.