Simulation of potential impact of air pollution from the proposed coal mining sites in Mui Basin, Kitui County

The potential for air pollutants transport, dispersion patterns and impacts within and around the Mui basin, Kitui County is simulated. The spatial-temporal distribution of air pollutants from the proposed coal mines was investigated using Hybrid Single Particle Lagrangian Integrated Trajectories (HYSPLIT) and dispersion analyses. The spatial distribution of wind patterns was investigated using wind rose to explain the observed air pollution distribution. The analysis was carried out for the dry and wet seasons of the study area namely: December, January, February (DJF), March, April, May (MAM), June, July, August (JJA) and September, October, November (SON) seasons. From the analysis, the season during which the exposure levels would pose much health threat was established based on frequency of winds blowing in certain direction and speed. By spatial analysis of the proximity of proposed mines and direction of dominant winds, areas most prone to pollution were delineated. The results showed that winds over the area were generally low and southerly. The residents to the northern and northwestern sectors would be at most at risk should the mining commence. Due to low wind speeds during January and the onset of JJA season, residents and workers at the mine would be affected adversely. The results may contribute to the design of effective control strategies to reduce impact of emitted pollutants

Simulated Impacts of Climate Change on Surface Water Yields over the Sondu Basin in Kenya

Potential impacts of climate change on surface water yields over the Sondu River basin in the western region of Kenya were analysed using the Soil and Water Assessment Tool (SWAT) model with climate input data obtained from the fourth generation coupled Ocean-Atmosphere European Community Hamburg Model (ECHAM4) using the Providing Regional Climates for Impacts Studies (PRECIS) model. Daily time step regional climate scenarios at a spatial grid resolution of 0.44Ëš over the Eastern Africa region were matched to the Sondu river basin and used to calibrate and validate the SWAT model.Analysis of historical and projected rainfall over the basin strongly indicated that the climate of the area will significantly change with wetter climates being experienced by 2030 and beyond. Projected monthly rainfall distribution shows increasing trends in the relatively dry DJF and SON seasons while showing decreasing trends in the relatively wet MAM and JJA seasons. Potential changes in water yields resulting from climate change were computed by comparing simulated yields under climate change scenarios with those simulated under baseline conditions. There was evidence of substantial increases in water yields ranging between 88% and 110% of the baseline yields by 2030 and 2050 respectively. Although simulated water yields are subject to further verification from observed values, this study has provided useful information about potential changes in water yields as a result of climate change over the Sondu River basin and in similar basins in this region

Consistent phenological shifts in the making of a biodiversity hotspot: the Cape flora

Background The best documented survival responses of organisms to past climate change on short (glacial-interglacial) timescales are distributional shifts. Despite ample evidence on such timescales for local adaptations of populations at specific sites, the long-term impacts of such changes on evolutionary significant units in response to past climatic change have been little documented. Here we use phylogenies to reconstruct changes in distribution and flowering ecology of the Cape flora - South Africa's biodiversity hotspot - through a period of past (Neogene and Quaternary) changes in the seasonality of rainfall over a timescale of several million years. Results Forty-three distributional and phenological shifts consistent with past climatic change occur across the flora, and a comparable number of clades underwent adaptive changes in their flowering phenology (9 clades; half of the clades investigated) as underwent distributional shifts (12 clades; two thirds of the clades investigated). Of extant Cape angiosperm species, 14-41% have been contributed by lineages that show distributional shifts consistent with past climate change, yet a similar proportion (14-55%) arose from lineages that shifted flowering phenology. Conclusions Adaptive changes in ecology at the scale we uncover in the Cape and consistent with past climatic change have not been documented for other floras. Shifts in climate tolerance appear to have been more important in this flora than is currently appreciated, and lineages that underwent such shifts went on to contribute a high proportion of the flora's extant species diversity. That shifts in phenology, on an evolutionary timescale and on such a scale, have not yet been detected for other floras is likely a result of the method used; shifts in flowering phenology cannot be detected in the fossil record

Extinction Risk and Diversification Are Linked in a Plant Biodiversity Hotspot

Plant extinction risks in the Cape, South Africa differ from those for vertebrates worldwide, with young and fast-evolving plant lineages marching towards extinction at the fastest rate, but independently of human effects

Detailed Analysis of Solar Ultraviolet-radiation - A Preliminary Investigation On Data Collected At Rome (la-sapienza-university)

The importance of solar ultraviolet radiation and its impact on human health is well known by the scientific community. Variations of the ozone layer can influence the UV radiation reaching the Earth's surface, especially at short wavelengths. Thus, it is important to study any possible ozone fluctuations. At the Physics Department, University of Pome, a Brewer spectrophotometer MKIV is located and is used to measure total ozone and UV flux in the 290-325 nm region with a resolution of 0.5 nm. Measurements of damaging ultraviolet radiation (DUV), defined as the incident radiation weighted against an action spectrum which relates the sensitivity of the human body to UV radiation, are also processed. This work is a preliminary investigation on the spectral solar UV radiation measurements performed at Rome during the years 1992/1993

Synoptic-scale fluctuations of total ozone in the atmosphere

A model, based on ozone-concentration tendency equation, is developed to study synoptic ozone-column variations. The application is referred to a middle-latitude site and to an atmospheric layer extending from the surface up to about 35-km altitude. Photochemical effects at the considered location for synoptic time scales are considered negligible. The data input consists of umkehr ozone profile, total ozone (obtained by Brewer No. 067, located at Rome) and horizontal wind at various levels. Analysis of several cases indicates that meridional advection is the main factor responsible for the observed synoptic-scale ozone fluctuations

An Investigation of A Possible Dependence of Brewer Number 67s Total-ozone Measurements On Some Atmospheric Parameters, Together With A Presentation of A Peculiar Synoptic Ozone Case At Rome

Brewer total ozone data (January-December 1992) measured at the Physics Department, Pome University > (41.9 degrees North, 12.5 degrees East) are analysed for dependence on Brewer internal temperature and some meteorological parameters. Non-parametric correlation analysis reveals the independence of total ozone from the internal Brewer temperature. Attention is focused on a peculiar case to show, by means of vertical wind velocity profile, the possible effects of lower stratospheric vertical advection on ozone fluctuations

Coupled Climate-Economy-Biosphere (CoCEB) model - Part 2: Deforestation control and investment in carbon capture and storage technologies

International audienceThis study uses the global climate-economy-biosphere (CoCEB) model developed in Part 1 to investigate economic aspects of deforestation control and carbon sequestration in forests, as well as the efficiency of carbon capture and storage (CCS) technologies as policy measures for climate change mitigation. We assume - as in Part 1 - that replacement of one technology with another occurs in terms of a logistic law, so that the same law also governs the dynamics of reduction in carbon dioxide emission using CCS technologies. In order to take into account the effect of deforestation control, a slightly more complex description of the carbon cycle than in Part 1 is needed. Consequently, we add a biomass equation into the CoCEB model and analyze the ensuing feedbacks and their effects on per capita gross domestic product (GDP) growth. Integrating biomass into the CoCEB and applying deforestation control as well as CCS technologies has the following results: (i) low investment in CCS contributes to reducing industrial carbon emissions and to increasing GDP, but further investment leads to a smaller reduction in emissions, as well as in the incremental GDP growth; and (ii) enhanced deforestation control contributes to a reduction in both deforestation emissions and in atmospheric carbon dioxide concentration, thus reducing the impacts of climate change and contributing to a slight appreciation of GDP growth. This effect is however very small compared to that of low-carbon technologies or CCS. We also find that the result in (i) is very sensitive to the formulation of CCS costs, while to the contrary, the results for deforestation control are less sensitive