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.

Background: This retrospective study was aimed to examine the distribution of some physicochemical parameters and its health impact in selected drinking water sources of Ethiopia. The study used 983 water samples collected from different regions of the country, and have been tasted in the Environmental Health Laboratory, Ethiopian Public Health Institute, from 2003 to 2011. The samples were collected from eight regions plus two administrative cities of the country and classified based on the source type as spring, well, and tap water. Methods:The physicochemical parameter analysis was executed based on standard method. Microsoft Excel and IBM SPSS Statistical software were used for the statistical analysis of median and graph. Results:The median result indicates that some values are within the acceptable range (PH, magnesium, chloride and sodium from spring and tap water), but, there are some measured values in some regions which are out of the recommended limit, (total hardness and calcium in spring, tap and well water). On the other hand, very high Sodium and chloride concentration were recorded in spring, tap, and well water sources of the region such as Somali, Afar, and Oromia. Conclusions:Those water sources that do not conform to National Standard will result in public health problem in long time exposure. Therefore, the local water authority shall strengthen local water quality monitoring and control system as well as risk assessment and management mechanisms.

Poor air quality is a development challenge. Urbanization and industrial development along with increased populations have brought clear socio-economic benefits to Low-and Middle-Income Countries (LMICs) but can also bring disadvantages such as decreasing air quality. A lack of reliable air quality data in East African cities makes it difficult to understand air pollution exposure and to predict future air quality trends. This work documents urban air quality and air pollution exposure in the capital cities of Kampala (Uganda), Addis Ababa (Ethiopia) and Nairobi (Kenya). We build a situational awareness of air pollution through repeated static and dynamic mobile monitoring in a range of urban locations, including urban background, roadside (pavement and building), rural background, and bus station sites, alongside vehicle-based measurements including buses and motorcycle taxis. Data suggest that the measured particulate matter mass concentrations (PM2.5, PM10) in all studied cities was at high concentrations, and often hazardous to human health, as defined by WHO air quality guidelines. Overall, the poorest air quality was observed in Kampala, where mean daily PM2.5 and PM10 concentrations were significantly above the WHO limits at urban background locations by 122% and 69% and at roadside locations by 193% and 215%, respectively. Traffic is clearly a major contributor to East African urban air pollution; monitoring in Kampala and Addis Ababa, on motorcycle taxis, in buses and at bus stations indicated that drivers and commuters were exposed to poor air quality throughout their commute. Road-related air pollution can also impact indoor locations near roads. Using one exemplar building located within Nairobi’s Central Business District, it is shown that measured outdoor PM concentrations significantly correlate with the indoor air quality (r = 0.84). This link between roadside emissions and indoor air pollution within buildings located close to the road should be explored more fully. This study, through a series of case studies, provides clear evidence that roads and traffic need to be a focus for mitigation strategies to reduce air pollution exposure in East African cities.

The authors have withdrawn this preprint due to author disagreement.

Background: The city of Addis Ababa is under rapid development and there are enormous construction activities along with rapid urbanization, and industrialization. These anthropogenic actions combined with population growth rate are affecting the water demand of the city. The overall purpose of this study is to model water supply and demand of the city and to identify potential water management strategies that supports the sustainable development goal number six (SDG6)-clean water and sanitation. Methods: We employed the Water Evaluation and Planning system (WEAP) modelling framework to analyze different scenarios for water demand and supply. The scenarios include population growth, living standard, as well as other supply and demand strategies. Results: For the modelling period, the reference scenario shows unmet water demand increases by around 48%, from 208 to 307 million cubic meter in 2015 and 2030 respectively. High population growth rate and high living standard scenarios have a great negative impact on the water supply system. Conclusions: Satisfying the future water demand of Addis Ababa will depend on the measures which are taken today. The integrated water management practices such as reuse of water and the selected future scenarios are proposed to decrease and manage the unmet water demand of the city. Hence, future predicted scenarios which is the combination of the external factors (i.e. population growth rate and living standard) and water management strategies were considered. From the analyzed scenarios, optimistic future strategies will support the management of the existing water supply and demand system of the city. Similarly, in the integrated management strategies scenario, it was assumed that measures were taken at both the demand and supply side to improve the efficiency of water in the entire chain. Thus, if the water sector professionals and other concerned bodies consider the selected scenarios, it will go a long way to solve the water shortage problem in the city, and this will also help to promote sustainable water management.