Analysis of trends in rainfall and water balance characteristics of Awka, Nigeria

Abstract

This paper analyses the trend in rainfall and water balance characteristics of Awka, Nigeria using the monthly rainfall data retrieved from the archives of the Nigeria Meteorological Agency in Lagos from 1976 to 2015. The tools employed for the study are linear regression analysis, cumulative sum (CUSUM) technique, Walter's cumulative index analysis and Thornthwaite's method. Rainfall was observed to have declined and generally below the climatological mean in the first decade, while from1988 to early 2000s, rainfall has maintained a steady rise. The length of rainy season has shown significant number of variations, but has recorded a general increase. The rainfall onset and cessation periods were predominantly March/April and October, respectively though significant changes in onset periods has been evident in the last 10 years with 6 out of the 10 having onset occurring in February. This study observed a reduction by one month in the periods of soil moisture utilization and increase by the same amount in the periods of soil moisture recharge. As a consequence, amount of water surplus has increased. However, this study provides explanation on the current state of rainfall in relation to climatic water budgeting for Awka and as such important for agricultural and water resource planning.

Climate-Driven Temporary Displacement of Women and Children in Anambra State, Nigeria: The Causes and Consequences

“…Notably, Akanwa and Ezeomedo [17] affirmed that additionally unpredictable weather conditions have aggravated the high precipitation levels in the area resulting in increased flooding and erosional problems traceable to variable timing and intensity of rainfall from the changing climate in Anambra State. Further, Nzoiwu et al [33] also reported about noticeable changes in climate causing a gradual shift in the rainy seasons such that the rainfall season has extended beyond June to September to the months of October and November. For the dry seasons, the months have extended from December to March.…”

“…Similarly, in 2013, Ogbaru LGA was flooded between the months of June and August causing a displacement of about 124, 859 people [25]. In 2018, about 9000 people from 1500 household were internally displaced from their homes in Ogabru LGA, and in 2020, about 5000 persons are displaced (homeless) in September during heavy storms and flooding in Ogabru LGA [33]. People could only access their homes using canoe, though movement to closer bigger cities, such as Onitsha town, can also be accessed via speed boats.…”

Assessment of Soil Moisture Storage In Nigeria Using Climatic Water Budgeting Approach

“…This will also enables us to determine the soil moisture seasons (Ritter, 2012). Soil moisture storage is very useful information for the determination of the onset and cessation of growing season (Chukwudi, Emma, Ifeanyi and Nwabueze, 2017;Ufoegbune, 2016;Ngetich and Mugendi, 2014;Umar, 2010, Rita, 2007Ati, Stigter, and Oladepo, 2001;Ati, 1996). When there is adequate moisture in the soil for crop growth, the growing season commences.…”