This paper presents the trend analysis of temperature in Gombe State using Mann-Kendall trend test. The annual average of Maximum and Minimum Temperature data was obtained from the Nigerian Meteorological Agency (NIMET), Gombe State. In order to determine the nature of the trend and significance level, Mann-Kendall trend test and Sen's estimate were employed. From this study, it was found out that Maximum and Average temperature exhibit positive Kendall's Z value which indicates an upward trend and also imply increasing trend over time. The Test statistic ( ) for maximum and average temperatures are 4.38 and 4.43 respectively. This indicates that there is a significant increase in the trend at 5% level of significance since (p-values (0.0001) <0.05). However, the Z value for minimum temperature (1.59) shows a positive trend but not significant at 5% significant level since the p-value is greater than the significant level (p-value (0.107)>0.05). It can be inferred from both Mann-Kendall and Sen's Slope that there is the tendency of increment in

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The need to understand the role of statistical methods for the forecasting of climatological parameters cannot be trivialized. This study gives an in depth review on the different variations of the Mann-Kendall (M-K) trend test and how they can be applied, regression techniques (Simple and Multiple), the Angstrom-Prescott model for solar radiation, etc. The study then goes ahead to apply some of them with data obtained from the Nigerian Meteorological Agency (NiMet), and applying tools like the python programming language and Wolfram Mathematica. Results show that the maximum ambient temperature for Calabar is increasing (Z = 2.52) significantly after the calculated p-value <0.05 (significant level). The seasonal M-K test was also applied for the dry and wet seasons and both were found to be increasing (Z = 3.23 and Z = 4.04 respectively) after their calculated p-values <0.05. The relationship between refractivity and other meteorological parameters relating to it was discerned using partial differential equations giving the gradient of each with refractivity; this was compared with results from the correlation matrix to show that the water vapor contents of the atmosphere contributes significantly to the variation of refractivity. Multiple linear regression has also been adopted to give an accurate model for the prediction of refractivity in the region after the residual error between the calculated refractivity and predicted refractivity was minimal.

Trend analysis of meteorological parameters (temperature, pressure, and relative humidity) as well as calculated refractivity, equivalent potential temperature (EPT) for a pseudo-adiabatic process, and field strength in Calabar, Southern Nigeria has been analyzed using Mann-Kendall trend test and Sen's slope estimator. Data of the meteorological parameters were obtained from the Nigerian Meteorological Agency (NiMet) in Calabar for 14 years (2005 -2018). Results show that the maximum and average temperature, atmospheric pressure, refractivity, EPT and field strength all exhibited a positive Kendall Z value with 2.52, 0.33, 3.83, 0.77, 0.44 and 3.18 respectively which indicated an increasing trend over time, with only maximum temperature, atmospheric pressure and field strength showing a significant increase at 5% (0.05) level of significance, since their calculated p-values (0.012, 0.0001, and 0.001) were less than 0.05. The relative humidity and minimum ambient temperature showed a decrease in trend over time as they both had a negative Kendall Z values (-0.11 and -1.09 respectively), however, together with the average ambient temperature and refractivity, their trend wasn't significant 5% level of significance since their calculated p-values were all more than 0.05. Linear regression, correlation and partial differentiation showed that relative humidity has the most effect on the changes in seasonal refractivity and an indirect relationship with field strength variability. The relationship between EPT and refractivity has been discovered to be very strong and positive. Descriptive statistics has been used to portray the seasonal and annual trend of all parameters.

Studies have been made to understand the fluctuations of temperature in regions around the world because of an ever changing variation due mostly to man’s anthropogenic activities. This study is focused on analysing the temperature variations in Calabar, Southern Nigeria for 20 years (1998 – 2018) using the Mann-Kendall trend test and Sen’s slope estimator. Results from the Mann-Kendall test shows that the annual trends of the maximum and average ambient temperature are both increasing after showing positive Kendall Z-values (1.04 and 0.10 respectively). The minimum ambient temperature annual trend was observed to be decreasing after having a negative Kendall Z-value (-0.32); the estimations from Sen’s slope agreed with these results. The p-values were calculated to be 0.745, 0.299, and 0.922 for the minimum, maximum, and average ambient temperature trend respectively; these values were all found to be less than all significant levels used 0.1% (0.001), 1% (0.01), 5% (0.05), and 10% (0.1). This shows that the trends were not increasing or decreasing significantly, hence there is “no significant trend”. This may be due to the almost unchanging weather condition in the region arising from its closeness to the Atlantic Ocean.

General evaluation of the world's and Africa's solar energy situation. Discussion on the current energy situation, variables, and applications in Nigeria. An in-depth look at the solar photovoltaic mathematical model and its key components. Estimating the potential amount of energy generated in different regions of Nigeria; using solar radiation data.

The intensity of solar energy that is received by a particular location is affected by most meteorological conditions including, the solar irradiance received by the location, precipitation, extreme heat as a result of the surface or ambient temperature, etc. We obtain the monthly global solar irradiation and ambient temperature for the three (3) eco-climatic zones in the south of Nigeria (17 locations) for 12 years (2005 - 2016) from the Photovoltaic Geographical Information System (PVGIS) Satellite. The goal of this study is to understand how regional meteorological conditions affect radiation and temperature reception. Monthly and annual trends were plotted and compared for both variables in each region to show the similarity or dichotomy in their trends. The Mann-Kendall (M-K) trend test has been adopted to reveal that the changes in the variations on an annual basis, and results showed that the trend were not significant for both variables. Box plots have been used to give a better description of the data, and compared to show similarities and differences. Finally, we adopted the Gaussian (normal) distribution to show, understand and compare the data distribution. Linear regression plots for each zone shows that the relationship between the solar irradiation and temperature is high. Results show that the climate and vegetation of a region contributes majorly to the variation of radiation and temperature. Inhomogeneityof data or results for locations in the same zones may be attributed to local meteorological conditions. The results obtained here will prove vital in decision making relating to the adoption of solar energy technologies in the region. Results show that the climate and vegetation of a region contributes majorly to the variation of radiation and temperature. Inhomogeneity of data or results for locations in the same zones may be attributed to local meteorological conditions.

Creating innovative ways for the identification of trends is a very vital part of atmospheric studies. Different climatic locations present their unique variations, calling for the dynamism of trend analysis. In addition to the widely adopted Mann-Kendall (MK) trend test, the new Şen’s innovative trend analysis (ITA) method has been applied to analyze the trends of refractivity related (atmosphere pressure –AP, vapour pressure – VP, ambient temperature – T) and equivalent potential temperature – EPT related parameters (mixing ratio of air – R, absolute temperature at the lifting condensation level – TL, potential temperature – PT). This analysis was perfomed using 40 years’ data (1981 – 2020) from 4 stations from each climatic zone of Nigeria (Calabar – Tropical monsoon, Ibadan – Tropical Savannah, Kano – Warm semiarid climate, and Kukawa – Warm desert climate). The MK trend test identified monotonic (entirely increasing or decreasing) trends for specific parameters across the climatic locations; the Şen’s ITA method was important in the identification of trends even for parameters that showed non-monotonic variations. Other comparisons between both methods were outlined and explained; correlation heat maps were used to show the relationship between all parameters for each climatic location, describing the effect of climate on the variations of these parameters. The low, medium and high values revealed from the Şen’s ITA method can be informative for telecom and renewable energy applications, guiding engineers and system designers to understand the trends within range of values for a particular climatic parameter.