Spatial and temporal heterogeneity of air pollution in East Africa.

East Africa's air pollution levels are deteriorating due to anthropogenic and biomass burning emissions and unfavorable weather conditions. This study investigates the changes and influencing factors of air pollution in East Africa from 2001 to 2021. The study found that air pollution in the region is heterogeneous, with increasing trends observed in pollution hot spots (PHS) while it decreased in pollution cold spots (PCS). The analysis identified four major pollution periods: High Pollution period 1, Low Pollution period 1, High Pollution period 2, and Low Pollution period 2, which occur during Feb-Mar, Apr-May, Jun-Aug and Oct-Nov, respectively. The study also revealed that long range transport of pollutants to the study area is primarily influenced by distant sources from the eastern, western, southern, and northern part of the continent. The seasonal meteorological conditions, such as high sea level pressure in the upper latitudes, cold air masses from the northern hemisphere, dry vegetation, and a dry and less humid atmosphere from boreal winter, further impact the transport of pollutants. The concentrations of pollutants were found to be influenced by climate factors, such as temperature, precipitation, and wind patterns. The study identified different pollution patterns in different seasons, with some areas having minimal anthropogenic pollution due to high vegetation vigor and moderate precipitation. Using Ordinary Least Square (OLS) regression and Detrended Fluctuation Analysis (DFA), the study quantified the magnitude of spatial variation in air pollution. The OLS trends indicated that 66 % of pixels exhibited decreasing trends while 34 % showed increasing trends, and DFA results indicating that 36 %, 15 %, and 49 % of pixels exhibited anti-persistence, random, and persistence in air pollution, respectively. Areas in the region experiencing increasing or decreasing trends in air pollution, which can be used to prioritize interventions and resources for improving air quality, were also highlighted. It also identifies the driving forces behind air pollution trends, such as anthropogenic or biomass burning, which can inform policy decisions aimed at reducing air pollution emissions from these sources. The findings on the persistence, reversibility, and variability of air pollution can inform the development of long-term policies for improving air quality and protecting public health.

Ecological balance emerges in implementing the water-energy-food security nexus in well-developed countries in Africa.

Although many African countries have made significant progress towards universal access to water, energy, and food resources (WEF), assessing the ecological response to the increasing productivity of these resources is not well researched, which carries the risk of ecological deficit, resource degradation, and inefficient policy responses to resource management. This study seeks to assess the ecological sustainability response to the high increase demand for WEF resources in well-developed African countries. The study developed new measurement metrics for the WEF production system, including three indicators of ecological footprint (EF), ecological biocapacity (EBC), and eco-balance. The overall analysis considers data from four distinct types of water and energy use activities, and eight distinct types of food consumption, in nine African countries with the highest WEF nexus performance. An evaluation tool for the Water, Energy, Food and Ecological Balance (WEFEB) nexus index is proposed as one of the study's outcomes. Despite having 100% access to WEF resources related to the SDG targets. The results reveal the significant levels of imbalance and large ecological deficits existing in many of the concerned countries, especially North Africa, Mauritius, and South Africa, which need to rethink their economic models. Projecting a sustained increase in resource demand so that each country achieves at least 1700 m3/capita/year as the minimum amount of water needed, most countries would suffer from a steady increase in ecological imbalance. According to the results, managing the ecological imbalances with increasing demand for WEF resources in well-developed African countries may require well-designed policies to effectively reduce certain types of human demand that have a large ecological footprint.