Two new bimetallic complexes, [Cp*2Yb]2(μ-1,3-(2,2‘-bipyridyl)-5-tBu-C6H3) (1) and [Cp*2Yb]2(μ-1,4-(2,2‘-bipyridyl)-C6H4) (2), and their corresponding two-electron oxidation products [1]2+ and [2]2+ have been synthesized with the aim of determining the impact of the bridging ligand geometry on the electronic and magnetic properties of these materials. Electrochemistry, optical spectroscopy, and bulk susceptibility measurements all support a ground-state electronic configuration of the type [(f)13-(πa*)1-(πb*)1-(f)13]. Density functional theory calculations on the uncomplexed bridging ligands as doubly reduced species also indicate that the diradical electronic configuration is the lowest lying for both meta- and para-bis(bipyridyl) systems. The electrochemical and optical spectroscopic data indicate that the electronic coupling between the metal centers mediated by the diradical bridges is weak, as evidenced by the small separation of the metal-based redox couples and the similarity of the f−f transitions of the associated dicationic complexes ([1]2+ and [2]2+) relative to those of the monometallic [Cp*2Yb(bpy)]+ analogue. The magnetic susceptibility data show no evidence for exchange coupling between the paramagnetic metal centers in the neutral complexes, but do indicate weak exchange coupling between YbIII and ligand radical spins on each of the effectively independent halves of the bimetallic complexes. These findings are in contrast to those reported recently for CoIII/II dioxolene bimetallic complexes bridged by these same bis(bipyridyl) ligands. The difference is attributed in part to the dominant singlet diradical character of the bridging ligands in the ytterbocene complexes. These experimental and theoretical results are consistent with expectations for organic diradical spin orientations for meta versus para substituents across a phenylene linker, but this effect does not induce significant longer-range superexchange or electronic interactions between the metal centers in these systems.

Charcoal is the main cooking source of energy used by millions of households in Somalia and has been described as "black gold" because of the revenue it produces. The objective of this study was to understand the extent of land cover change, given the widely reported charcoal trade in the South of Somalia. Land cover change analysis was done using remotely data from Landsat imagery. Different images covering all districts in Lower Jubba from 1993/95, 2000 and 2014 were analysed and compared. A survey was conducted in Lower Jubba to determine the divers of deforestation and degradation in the region. Results showed a 50% reduction in forest cover and a 17% reduction in woodlands between 1993/95 and 2014. Results from the survey showed charcoal production as a maladaptive response to climate extremes. If business continues as usual with deforestation, the entire area could completely be deforested in the future. Results from this study can be useful in the development of strategies for reforestation, environmental management and sustainable development for this region.

Somalia has faced severe challenges linked to climate variability, which has been exacerbated by conflict and limited governance that persisted for decades. Today climate extremes such as floods, drought, and coastal marine severe systems among others are always associated with the destruction of property and livelihoods; losses of lives lost, migrations, and resource based conflicts among many other miseries. Intergovernmental Panel on Climate Change (IPCC) has shown that climate change is real and requires sound knowledge of local future climate change scenarios. The study attempted to provide projected rainfall and temperature change scenarios over Lower Jubba, Somalia. This was done using the downscaled Coordinated Regional Downscaling Experiment (CORDEX) RCMs data. The simulated temperature and rainfall data derived from the CORDEX RCMs ensemble were compared with the observed data. The study focused on the IPCC projected periods of 2030, 2050 and 2070 benchmarks. Analysis of the projected rainfall indicated a decreasing trend in rainfall leading up to 2030 followed by an increase in rainfall with the 2050 and 2070 scenarios. In the case of temperature, the projections from all the models showed increase in minimum and maximum temperatures in all seasons and sub periods, like being observed by temperature projection over other parts of the world. The 2030, 2050 and 2070 projected rainfall and temperature change scenarios show that Somalia future development and livelihoods will in future face increased threats of climate extremes unless effective climate smart adaptation systems form integral components of national development strategies.

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Climate is changing at an alarming rate threatening the critical pillars for environmental, social and economic development. Signals of climate change seems to be quite real for many African communities. Somalia, is one the countries of the GHA that has faced unique climate variability and climate change challenges, within severe conflict environment and lack of a stable government for many years. The objective of this study was to understand the past and present rainfall and temperature patterns over Lower Jubba. Rainfall data used extended from 1981-2015, while those of temperature 1981-2012. The study for rainfall concentrated within the two main rainfall seasons namely Gu and Deyr. Temperature data were however analysed for all the four seasons, June to August, December to February, September to November, and March to May. The data were subjected to various trend analysis methods that included time series plots of the graph of the specific rainfall and temperature observations. Two statistical approaches namely linear regression and Man-Kendal non-parametric statistics were employed in testing the significance of the slope of the rainfall and temperature time series for specific seasons. Evidences from tend analyses showed increasing trends in both minimum and maximum temperatures at all locations and all seasons, which is consistent with patterns that have been delineated in many parts of the Greater Horn of Africa. IPCC among many other past studies have linked global temperature increase worldwide to climate change induced global warming. Due to limitation in the length of temperature data used in this study, it be would be difficult to attribute the observed trends in temperature records entirely to climate change. The results from rainfall showed that most of the trends observed were not statistically significant. Few significant trends that were delineated at some locations were not spatially consistent over large areas. The most dominant characteristics of rainfall time series were high degree of interannual variability with recurrences in high/low value extremes that are often associated with floods/droughts. Some of these extremes occurred during El Nino /La Nina years. Results are consistent with those from some past studies in the region. The results from the study can be used in the planning and risk management of all climate sensitive socioeconomic development activities in Somalia, especially in the development of strategy for sustainable community livelihoods and development in Lower Jubba.