Open Access Opinion Article
On reviewing the development of the research methodologies on climate change and sea level rise during the last two decades, it is observed that the assumed scenarios for apprehending the rise in global temperature are grounded on a lot of uncertainties. The real-time data varies from IPCC’s predictions. The gradual transition on the emission pathway scenarios from SRES (2000) till RCPs in AR5 of IPCC depicts the conceptual difference between the two concepts in scenarios. SRES represented detailed socio-economic-based scenarios, but RCPs are based on the capacity of a gas affecting the change in energy in the atmosphere due to GHG emissions known as Radiative Forcing. Considering the possible range of the radiative forcing values in 2100, AR5 of IPCC considers the four RCPs numbered as 2.6,4.5, 6.0 and 8.5 as per greenhouse gas concentration trajectories (not emissions). The present condition of melting of ice sheets at Antarctica and Greenland is quite high and it is understood that such melting will continue. Even in a situation, if the anthropogenic emission of GHGs is immediately stopped, the self-sustained melting will continue. Models so far being based on numerical and probabilistic approaches are expected to undergo abrupt change because of the current inconsistent ice sheet dynamics. Considering deep uncertainty in socio-political and economic changes amongst nations, the importance of usability of model hierarchy for the complex science of climate change is becoming unforecastable, in the prevalent ice dynamics during accelerated warming situations. In reality, the predictions are becoming less reliable. Possibility of the scenarios likely to be changed are apprehended during the advent of CMIP6 and the variations in contributing factors in the form of SSPs in the upcoming IPCC AR6, in 2022 and it is indicated that the research may take a new turn. A multidisciplinary approach to research with minimum uncertainty in a more precise and finer manner is the need of the day.
Open Access Original Research Article
Detailed geologic mapping and geochemical analysis of coal samples around Abocho area, northern Anambra Basin, Nigeria was conducted in order to assess the quality of the coals in the area. Proximate and ultimate analyses were carried out on coal samples from the Mamu Formation to determine its chemical characteristics. Physical analysis was also carried out on the coal samples to determine the specific gravity, density and hardness. Geochemical analysis was also carried out on the associated rocks in the study area (Abocho), particularly Shales and Clays to determine their major oxides composition. The area is composed of the Maastrichtian Mamu Formation overlain by the Ajali Sandstone of the same age both dipping between 16°E and 19°E. The geologic mapping of Abocho area revealed two mappable lithologic units: The Mamu Formation and the Ajali Sandstone. The Proximate analyses indicates that the coal contains an average 7.15%, 35.53%, 36.24% of moisture content, volatile matter and fixed carbon respectively. These burns to generate 4,339 kcal/kg calorific value with 20.80% ash yield. The result of the ultimate analysis shows 57.81% organic carbon, 4.15% hydrogen, 8.41% oxygen, 1.39% nitrogen and 0.3% Sulphur. The physical analysis revealed that, the coal has an average specific gravity of 1.5g/cm, average density of 1.4g/cm3 and average hardness of 1.2. These characteristics qualify the coal to be ranked as high volatile sub-bituminous to marginal lignite. The coal is thus, suitable for combustion, gasification, electric power generation and industrial uses. Geochemical results show that the Shale contains 60% Silica (SiO2) and 26%Alumina (Al2O3) constituting 86% of bulk chemical composition. The Clay contains 70% Silica (SiO2) and 25% Alumina (Al2O3), constituting 95% of bulk chemical composition. The occurrences of CaO, NaO and K2O which are the major component of feldspar in clay suggests the clay to be of granitic origin possibly from Oban massif, east of the Anambra Basin. It also suggests low feldspar content.
Open Access Original Research Article
Natural radioactivity exists in primordial formations such as rocks, soils, water and air where long lived radionuclides such as , , and their affiliates are found. This work was done to determine the specific activity of radionuclides, soil to cassava transfer factor and the effective dose due to consumption of radionuclide in cassava products in Ikot Ekpene Local Government Area, Akwa Ibom State. The specific activity of 40K, 238U and 232Th in soils and cassava in the study area was measured using gamma spectrometry. Mean specific activity in soils ranged from BDL to 153.46 ± 10. 99 Bq/Kg for 40K; BDL to 31. 22 ± 7.49 Bq/Kg for 238U and 1.03 ± 0.10 to 12.71 ± 1.24 Bq/Kg for 232Th. Mean specific activity of the radionuclides in cassava in all locations ranged from 119.86 ± 8.61 to 601.28 ± 43.23 Bq//Kg for 40K; below detectable limit (BDL) to 15. 89 ± 1.55 Bg/Kg for 238U and BDL to 15. 89 ± 1.55 Bq/kg for 232Th. Transfer factors ranged between 3.64 to 4.18 for 40K; 1.30 to 1.82 for 238U and 0.51 to 0.72 for 232Th. Effective ingestion dose due to the consumption of cassava from the area ranged between 0.99 mSv/yr to 1.08 mSv/yr and 2.68 mSv/yr to 29.16 mSv/yr for children and adult respectively. Most of the TF and effective ingestion dose results for this study were above the recommended value of unity which suggests that consumption of cassava from the studied area may pose radiological health.
Open Access Original Research Article
Urban growth in the context of sub-Saharan Africa generally introduces attendant effects. Some of these include land use conflicts, pressure on municipal services and the challenges of urban poverty. While these issues have received significant attention, an issue which seemed to have eluded geographical literature, at least in the context of Bamenda, centres on the extent to which urban expansion triggers land conflicts. This paper analyses the trend of urban expansion in Bamenda II, and explores the relationship between urban expansion and land conflicts. A total of 80 households were randomly sampled, complemented by participant observation and focus group discussions. The Pearson’s Correlation Coefficient revealed a positive correlation between urban expansion and land conflicts. It is therefore necessary for policy interventions to regulate the pace of urban expansion with a view to preserving the last vestiges of natural and agricultural space. Further conflicts could be avoided through a clear demarcation of boundaries, including the facilitation of the process of acquiring land titles. This will reduce the cases of land conflict and haphazard urban expansion.
Open Access Review Article
For years, Accra has been facing huge environmental challenges. Efficient policy frameworks coupled with prudent urban management are deemed as reasonable balance to environmental benefits. Research reveals urban areas in Ghana are confronted with the rapid loss of natural resources as urbanization increases. This synthesis report examines the ramifications of major issues faced by the Greater Accra region based on existing literature by (i) highlighting contemporary environmental problems in Accra (ii) probing into human-induced and natural factors that alterate environmental harmony in the study area (iii) discussing measures on safeguarding the environment through a sustainable approach in Accra, and (iv) presenting policy implications of environmental problems in Accra. Findings indicated urbanization, poverty and inappropriate urban planning systems influence environmental degradation in the study domain. Anthropogenic activities such as pollution and natural hazards like: flooding, drought and windstorms events have altered the physical properties of Accra. This paper reveals the assumption and execution of values to safeguard environmental resources in the Greater Accra Metropolitan Area.