Sub-Saharan Africa's international migration constrains its sustainable development under climate change

Sub-Saharan Africa (SSA) is seen as a region of mass migration and population displacement caused by poverty, violent conflict, and environmental stress. However, empirical evidence is inconclusive regarding how SSA’s international migration progressed and reacted during its march to achieving the Sustainable Development Goals (SDGs). This article attempts to study the patterns and determinants of SSA’s international migration and the cause and effects on sustainable development by developing a Sustainability Index and regression models. We find that international migration was primarily intra-SSA to low-income but high-population-density countries. Along with increased sustainability scores, international migration declined, but emigration rose. Climate extremes tend to affect migration and emigration but not universally. Dry extremes propelled migration, whereas wet extremes had an adverse effect. Hot extremes had an increasing effect but were insignificant. SSA’s international migration was driven by food insecurity, low life expectancy, political instability and violence, high economic growth, unemployment, and urbanisation rates. The probability of emigration was mainly driven by high fertility. SSA’s international migration promoted asylum seeking to Europe with the diversification of origin countries and a motive for economic wellbeing. 1% more migration flow or 1% higher probability of emigration led to a 0.2% increase in asylum seekers from SSA to Europe. Large-scale international migration and recurrent emigration constrained SSA’s sustainable development in political stability, food security, and health, requiring adequate governance and institutions for better migration management and planning towards the SDGs. GRAPHICAL ABSTRACT: [Image: see text] SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s11625-022-01116-z

Evaluation of Economic Linkage between Urban Built-Up Areas in a Mid-Sized City of Uyo (Nigeria)

Urban growth has transformed many mid-sized cities into metropolitan areas. One of the effects of this growth is a change in urban growth patterns, which are directly linked with household income. Hence, this paper aims to assess the effect of different economic variables that trigger urban built-up patterns, using economic indicators such as city administrative taxes, a socio-economic survey of living standards, household income and satellite data. The regression model was used and adapted, and a case study is presented for the mid-sized city of Uyo in southeastern Nigeria. The result shows sparse built-up growth patterns with numerous adverse effects. Although, there is awareness of the impact of unregulated sparse built-up growth patterns in the literature, little attention has been given to this growth pattern in Africa. The results also show that increases in federal allocation (27%), investment tax (22%), direct tax (52%) and indirect tax (26%) have led to urban expansion into vegetative land and have a causal correlation with different built-up areas. Hence, medium and high-income earners migrate to suburban areas for bigger living space and a lack of basic social amenities affects the land value in suburban areas. They also assist in the provision of social amenities in the neighborhood

Scenarios of Solar Energy Use on the “Roof of the World” : Potentials and Environmental Benefits

Peripheral mountain areas in developing countries are often characterized by energy poverty but also by high solar energy potential. The Eastern Pamirs of Tajikistan are a prime example of this situation, with their lack of energy infrastructure, remoteness, pressure on local natural resources, and high incident radiation amounts. An integrative assessment of the potential for photovoltaic power generation is lacking for this region, as well as for many other mountain environments. We assessed the natural potential, feasibility, and likely effects of increased photovoltaic electricity generation, using climate data, biomass data, a spatial radiation model, and fieldwork- and literature-based scenarios of energy requirements and financial conditions. Results indicated that using a photovoltaic power plant to generate enough energy for boiling water is feasible in the study area within reasonable cost limits. This could significantly alleviate energy poverty, increase carbon sequestration by up to 1500 t/y, and reduce the loss of dwarf shrub stands by up to 2000 ha/y. Our results illustrate that the integrative approach presented in this article can be applied straightforwardly when some climatic measurements and field observations are available and that photovoltaic energy is an important renewable-energy resource for the sustainable development of peripheral high-mountain communities

Potential of Space-Borne Hyperspectral Data for Biomass Quantification in an Arid Environment : Advantages and Limitations

In spite of considerable efforts to monitor global vegetation, biomass quantification in drylands is still a major challenge due to low spectral resolution and considerable background effects. Hence, this study examines the potential of the space-borne hyperspectral Hyperion sensor compared to the multispectral Landsat OLI sensor in predicting dwarf shrub biomass in an arid region characterized by challenging conditions for satellite-based analysis: The Eastern Pamirs of Tajikistan. We calculated vegetation indices for all available wavelengths of both sensors, correlated these indices with field-mapped biomass while considering the multiple comparison problem, and assessed the predictive performance of single-variable linear models constructed with data from each of the sensors. Results showed an increased performance of the hyperspectral sensor and the particular suitability of indices capturing the short-wave infrared spectral region in dwarf shrub biomass prediction. Performance was considerably poorer in the area with less vegetation cover. Furthermore, spatial transferability of vegetation indices was not feasible in this region, underlining the importance of repeated model building. This study indicates that upcoming space-borne hyperspectral sensors increase the performance of biomass prediction in the world’s arid environments

Preserving a Comprehensive Vegetation Knowledge Base - An Evaluation of Four Historical Soviet Vegetation Maps of the Western Pamirs (Tajikistan)

Vanselow KA, Samimi C, Breckle S-W. Preserving a Comprehensive Vegetation Knowledge Base - An Evaluation of Four Historical Soviet Vegetation Maps of the Western Pamirs (Tajikistan). PLOS ONE. 2016;11(2): e0148930.We edited, redrew, and evaluated four unpublished historical vegetation maps of the Western Pamirs (Tajikistan) by the Soviet geobotanist Okmir E. Agakhanjanz. These maps cover an area of 5,188 km(2) and date from 1958 to 1960. The purpose of this article is to make the historic vegetation data available to the scientific community and thus preserve a hitherto non available and up to now neglected or forgotten data source with great potential for studies on vegetation and ecosystem response to global change. The original hand-drawn maps were scanned, georeferenced, and digitized and the corresponding land cover class was assigned to each polygon. The partly differing legends were harmonized and plant names updated. Furthermore, a digital elevation model and generalized additive models were used to calculate response curves of the land cover classes and to explore vegetation-topography relationships quantitatively. In total, 2,216 polygons belonging to 13 major land cover classes were included that are characterized by 252 different plant species. As such, the presented maps provide excellent comparison data for studies on vegetation and ecosystem change in an area that is deemed to be an important water tower in Central Asia

Adaptation as by-product: migration and environmental change in Nguith, Senegal

In the debate about the nexus between environmental change, climate and migration much attention has been given to a changing climate as a push factor for migration. A more recent strand of academic work focuses on migration as a means to enhance adaptation capacities and resilience. This article questions these intentional attributions and starts from the observation that migration is occurring regardless of environmental or climatic change and connects people and places through shared social and cultural identities and the flow of ideas and resources. Drawing on a case study of Nguith, a village in the Senegalese Sahel with a long and complex migration history, it is shown how migration and material and non-material remittances have led (in a way accidentally) to an increased independence from local agro-ecological conditions. Therefore, we investigate the social, cultural and historical background of the people of Nguith with regard to their mobility and trace the continents-traversing migration network and connected translocal spaces. Finally, we explain the cohesive forces of this community that perpetuate and reinforce migration and show the effects of migration on everyday life, economic development in the village and resulting land-use change

Data and methods in the environment-migration nexus: a scale perspective

The relationship between environment and migration has gained increased attention since the 1990s when the Intergovernmental Panel on Climate Change projected climate change to become a major driver of ­human migration. Evaluations of this relationship include both quantitative and qualitative assessments. This review article introduces the concept of scale to environment-migration research as an important methodological issue for the reliability of conclusions drawn. The review of case studies shows that scale issues are highly present in environment-migration research but rarely discussed. Several case studies base their results on data at very coarse resolutions that have undergone strong modifications and generalizations. We argue that scale-related shortcomings must be considered in all stages of environment-migration research

Measurements meet human observations : integrating distinctive ways of knowing in the Pamir Mountains of Tajikistan to assess local climate change

<jats:title>Abstract</jats:title><jats:p>In mountain environments dimensions of climate change are unclear because of limited availability of meteorological stations. However, there is a necessity to assess the scope of local climate change, as the livelihood and food systems of subsistence-based communities are already getting impacted. To provide more clarity about local climate trends in the Pamir Mountains of Tajikistan, this study integrates measured climate data with community observations in the villages of Savnob and Roshorv. Taking a transdisciplinary approach, both knowledge systems were considered as equally pertinent and mutually informed the research process. Statistical trends of temperature and snow cover were retrieved using downscaled ERA5 temperature data and the snow cover product MOD10A1. Local knowledge was gathered through community workshops and structured interviews and analysed using a consensus index. Results showed, that local communities perceived increasing temperatures in autumn and winter and decreasing amounts of snow and rain. Instrumental data records indicated an increase in summer temperatures and a shortening of the snow season in Savnob. As both knowledge systems entail their own strengths and limitations, an integrative assessment can broaden the understanding of local climate trends by (i) reducing existing uncertainties, (ii) providing new information, and (iii) introducing unforeseen perspectives. The presented study represents a time-efficient and global applicable approach for assessing local dimensions of climate change in data-deficient regions.</jats:p&gt