Climate change and trend analysis of temperature: the case of Addis Ababa, Ethiopia

Abstract

Background This paper presents the trend analysis of temperature and the effect of climate variation in the city of Addis Ababa, Ethiopia. The paper seeks to provide up-to-date information for the better management of climate change in the city. The analysis is based on the temperature difference in the city over two stations—Bole and Entoto. The overall purpose of this study is to investigate the possible trend of temperature variation as well as the effect of climate change in the study area. Method The Mann-Kendall (MK) trend test and Sen's slope estimate were employed to find the nature of the temperature trend and significance level in the city. Results It was found that the MK2/MK3 statistic (Z) value for minimum, maximum and average temperatures for Bole station are 6.21/5.99, 2.49/2.6, and 6.09/6.14 respectively. The positive Kendall's Z value shows an upward trend and implies an increasing trend over time. This indicates a significant increase in the trend at a 5% level of significance since the significance level (alpha) is greater than the computed p-value (0.05 > p-values (0.0001)). Whereas for Entoto station, the MK1 statistic (Z) results are 1.64 for minimum, while the MK2/MK3 static (Z) are 0.71/0.65 for the maximum, and 0.17/1.04 for average temperature, and this positive value shows an indicator of an increasing trend. However, the increase is not significant at the 5% significant level since the computed p-value is larger than the significant level (alpha = 0.05). Conclusions There is a tendency of temperature increments in Bole station. This could be due to the influence of climate change which can lead to weather extremes in the capital city. Therefore, the study recommends that the variability of temperature needs further monitoring technique, and there is a need to consider the increasing temperature trend to minimize its effects on human health.

Hydro-Meteorological Trends in an Austrian Low-Mountain Catchment

“…Additionally, the Theil-Sen robust estimate was computed [45,46] to evaluate the magnitude of the trend. This approach has been successfully used to assess climate developments in numerous earlier studies (e.g., [47][48][49][50]) and was therefore applied in the current study.…”

Trend Analysis of Climatic and Hydrological Parameters in Ajora-Woybo Watershed, Omo-Gibe River Basin, Ethiopia

“…Generally, CV is used to classify the degree of variability of events into three: low (CV < 20), moderate (20 < CV < 30), and high (CV > 30). Higher CV shows more variation in parameters and vice versa (Alemu & Dioha, 2020;Bayable et al, 2021) Correlation analysis between climate and river discharge Pearson correlation coe cients (r) was calculated for the degree of the linear relation between climate variables (rainfall and temperature) with river discharge. Moreover, the correlation between climate variables and runoff helps us to estimate their relationships.…”

“…Abegaz, 2020;Alemu & Dioha, 2020;Belihu et al, 2018;Gedefaw et al, 2019;Mubialiwo et al, 2020). It is also used to determine whether a set of data values is increasing or decreasing over time, and whether the trend is statistically signi cant in either direction.…”

Sea surface temperature trend analysis by Mann-Kendall test and sen’s slope estimator: a study of the Hai Phong coastal area (Vietnam) for the period 1995-2020

“…This method computes the linear rate of the slope and the intercept, as shown in Sen's approach (Sen, 1968). The combining of MK test and Sen's pitch is widely documented in various literature, as a powerful trend test for practical analysis of seasonal and annual trends, and is preferred over other tests because of its applicability to data time series that do not follow a statistical distribution (Duan et al, 2019;Gao et al, 2019;Dong et al, 2019, Alemu andDioha, 2020). Thus, this study has employed the MK trend test and Sen's slope estimate to understand the SST trend and significance level in the Hai Phong coastal area.…”