This paper presents exergetic sustainability evaluation of a Recirculating Aquaculture System (RAS). Some environmental and sustainability aspects of the RAS are investigated in terms of exergetic sustainability parameters. In this regard, the exergetic parameters, such as exergetic efficiency, waste exergy ratio, exergy recoverability ratio, exergy destruction ratio, environmental impact factor, and exergetic sustainability index are studied. The results show that increasing waste exergy ratio increases the exergetic efficiency and decreases exergetic sustainability index. However, the environmental impact of the RAS increases as the waste exergy ratio increases. Thus, it can be said that, the RAS requires much more improvement because of the higher environmental impact factor and lower exergetic sustainability index, resulting from the heat gained from the environment, the back water from the components in the system, the increasing quantity of the unused waste, and the high capacity of the pumps based on the fish production capacity of the system.

Ocean stores energy in the form of currents, waves, tides, heat and salinity that can help to alleviate worldwide demand for power and the global climate change threat. Exergy analysis can be applied to evaluate the work potential (extractable) that a resource contains. This paper focuses on the exergy content that can be extracted from ocean reservoirs and provides a review of existing the technology installed for harvesting ocean energy.

A comprehensive thermodynamic modelling is reported of a trigeneration system for cooling, heating, electricity generation and hot water production. This trigeneration system consists of a gas turbine cycle, an organic Rankine cycle (ORC), a single-effect absorption chiller and a domestic water heater. Energy and exergy analyses, environmental impact assessments and related parametric studies are carried out, and parameters that measure environmental impact and sustainability are evaluated. The exergy efficiency of the trigeneration system is found to be higher than that of typical combined heat and power systems or gas turbine cycles. The results also indicate that carbon dioxide emissions for the trigeneration system are less than for the aforementioned systems. The exergy results show that combustion chamber has the largest exergy destruction of the cycle components, due to the irreversible nature of its chemical reactions and the high temperature difference between the working fluid and flame temperature. The parametric investigations show that the compressor pressure ratio, the gas turbine inlet temperature and the gas turbine isentropic efficiency significantly affect the exergy efficiency and environmental impact of the trigeneration system. Also, increasing the turbine inlet temperature decreases the cost of environmental impact, primarily by reducing the combustion chamber mass flow rate.

Growing energy demands and the desire to reduce pollution have increased interest in and research on unconventional power plant technologies. Geothermal power plant technology is an important area being explored as a renewable and environmentally benign alternative to fossil fuel technologies. Geothermal power plants have sources of emissions associated with use, including the use of evaporation ponds. An example of a geothermal power generation unit that utilizes an evaporation pond to manage spent geothermal fluids during its operation is the Cerro Prieto I plant in Mexico. A theoretical model is developed to retrofit the plant with geothermal fluid re-injection. Energy and exergy analyses are performed for the standard plant, using the evaporation pond, as well as a hypothetical system utilizing fluid re-injection. The plant without re-injection is found to have an energy efficiency of 12.6% and an exergy efficiency of 47.5%. With re-injection the energy efficiency is 16.5% and the exergy efficiency is 51.5%. The greatest loss in the standard system is through direct discharge of the geothermal fluids to the evaporation pond.

In this paper, a comprehensive thermodynamic analysis of Organic Rankine Cycle (ORC) using different working fluids driven by renewable/waste low-grade heat sources is conducted, and the performance and environmental characteristics of cycle, especially the potential CO₂ emission, are investigated. The comparative evaluation of cycle using a combined energy and exergy analysis is performed by varying certain system operating parameters such as efficiencies, mass flow rate, cycle irreversibility and heat input at various temperatures and pressures. Moreover the toxicity, flammability, ODP and GWP of different working fluids besides utilizing renewable heat sources are studied as a safety and environmental assessment. The results from this analysis provide valuable insight into selection of the most suitable fluids for power generating applications using low-temperature heat sources..

Atmospheric carbon dioxide plays an important role in climate change on the geological time scale. To combate the climatic change and risk of global warming, and to save the planet, it is urgent to reduce and stabilize the concentrations of carbon dioxide (CO₂) and other greenhouse gases (GHGs) in the earth's atmosphere. This review has mainly studied the possible strategies of carbon sequestration by natural and engineering techniques, and off-setting the GHGs emissions, especially focusing on the long-term storage of carbon in oceans, soils, vegetation, geologic formations, industrial materials, and engineered construction works. Carbon can be sequestrated by absorption of carbon dioxide via physicochemical process and biological pump by phytoplankton, by application of iron nutrients in oceans, and engineering techniques for direct injection in oceans by enhanced dilution by CO₂ hydrate particles from the moving ship hydrate discharge. The photosynthesis by terrestrial plants, largest carbon sinks, can augment the carbon sequestration by (1) the increase of forest growth on existing and unmanaged all available lands in the tropical and other regions, (2) the increase of forest or grassland in arid and semiarid regions, desert, semi desert and savanna areas, (3) afforestation of marginal agricultural land, (4) development of forestry or grassland in degraded mining areas, (5) cultivating urban and residential turf grass, (6) preserving forestry in polar region, (7) soil restoration and soil management practices for regenerative agriculture, grassland and pastureland, (8) agroforestry practices and growing energy crops on spare lands. The artificial engineered techniques can be used for carbon sequestration by energy-efficient and energy-capturing building construction, geopolymer cement, capture and storage of industrial carbon emissions, engineered underground geological sequestration along with mineral carbonation of CO₂ (e.g., in deep ocean, geological strata, declining oil field, saline aquifer, and unminable coal seam), and construction of landfills and safe-guard wetlands. Engineering techniques are expensive and have leakage risks. In comparison, natural biotic techniques are cost-effective processes and have numerous ancillary benefits. Although all the possible strategies for the carbon sequestration are implemented, it would be difficult to reduce the concentrations of GHGs from atmosphere and mitigate the effects of climatic change, unless the viable strategies are adopted in anthropogenic activities for (1) the lowering of CO₂ emissions from energy, fossil fuel combustion, process industry, degrading soil cultivation, land-use change, deforestation, biomass burning, draining of wetlands etc, (2) reducing the global energy use, (3) off-setting CO₂ emissions and (4) developing low or no-carbon fuel from bio-diesel and renewable energies of solar, wind and hydraulic power.

Increasing concentration of green house gases in the atmosphere has already resulted in chaotic weather systems that will have major effects on the coastal ecosystem, and drought and salinity will escalate. Of all the green house gases, the major culprits being CO₂ and methane. To bring down the CO₂ levels in the atmosphere, spreading of green cover seems to be one of the biological remedies to mitigate the threatening effects of global warming. Photosynthetically four kinds of plants can be recognized such as C3, C4, CAM and C3-C4 intermediates plants, of which C4 is an efficient fixer of atmospheric CO₂. In addition, attempts are being made to introduce C4 genes into C3 plants (C3 plants harboring photosynthetic genes such as Phospho-enolpyruvate carboxylase (PEPCase) and pyruvate orthophosphate dikinase (PPdK)) to make them more adoptable to drought, salinity and high temperature the major environmental effects of global warming. Exploitation of the coastal regions for cultivation of many types of seaweeds as vegetables for human consumption, Phytoplankton enrichment both in saline waters of oceanic environment and fresh water will lead to further CO₂ depletion in the atmosphere. CAM plants in particular to some extent can take care of respired out CO₂ at night.

In the last decade, the energy sector has suffered several changes related not only with the decrease of conventional hydrocarbons reserves, i.e. oil and associated natural gas, but also and especially with restrictions imposed by mechanisms in the scope of sustainable environment. The energy dependency is one of the major problems that all countries must deal nowadays, and all the international energy bodies agree that it will be impossible, to the most part of the countries, to become energetically independent. Some international entities advised either governmental parties, as well as, other energy players to develop strategies in different fields in order to reduce external dependency. Additionally, the sustainable energy plan developed by the European Commission is closely related to sustainable environment and consequently to all policies involved in reducing the greenhouse gases effect. In this perspective, and knowing that nowadays it is not yet possible to displace fossil fuels from the energy scenario, it is pertinent to apply new technologies, such as CCS (carbon capture and storage) technologies. One of the current main objectives in CCS technologies deals specifically with CO₂ geological storage/sequestration, mostly in depleted oil and gas reservoirs, saline aquifers and in unminable coal seams, the later taking into account the so-called hydrocarbons (CBM) enhanced production.
This paper deals with the study of different coal samples in what concerns their storage and gas circulation capacities. In fact, both processes are highly dependent on physical and chemical properties of coal, which are intimately related to its genetic conditions. As a matter of fact, to understand the mechanisms involved in coal formation process, it is crucial to study in detail the deposition environmental conditions, as well as, the incarbonization process. Moreover, the coal organic components evolution is also directly related to both deposition conditions and the incarbonization process. In terms of petrographic parameters and besides the inorganic components (mineral matter content), the organic compounds of coal correspond to three quite different maceral groups (vitrinite, inertinite and liptinite) and the incarbonization stage, or rank, can be determined by the mean random vitrinite reflectance. All these parameters strongly influence the storage and the gas circulation capacities of a coal, since they can change the pore sizes, as well as, the porous structure organization and therefore the internal surface area.

Storage of CO₂ as hydrates in sub-seabed sediments has been pointed out as an alternative solution for the geological storage of CO₂, particularly suitable for offshore areas where large ocean depths and low temperatures are reached at short distance from the onshore. This is the case for Portugal, where the continental shelf can be as narrow as 10 km. This paper presents the works conducted to identify the CO₂ Hydrates Stability Zone, i.e. the areas where CO₂ hydrates may form and remain stable, in the deep offshore of Portugal. The methodology adopted involved building maps of geothermal gradient, temperature of water, detailed bathymetry and conversion to hydrostatic pressure, and maps of sediment thickness. These maps were integrated in a GIS environment and a Fortran code was implemented to compute the thickness of the Hydrate Stability Zone, based on the pressure and the temperature conditions on the sub-seabed sediments. Preferential areas, where further studies should be conducted, were defined based on thickness and thickness variation of the Stability Zone, depth of the water column and distance from the main harbours.

Since carbonates are at a lower energy state than free CO₂, storage through carbonation of silicate rocks is thermodynamically favoured and proceeds spontaneously by releasing heat. In an in-situ CO₂ injection site, the heat released in these exothermic reactions can be exploited in a geothermal plant, effectively contributing towards the economic viability of the storage process.
Our calculations suggest the possibility of generating up to about 65 TWh of electrical energy while capturing permanently about 1Gton CO₂ per 1 km3 of peridotite or basalt rock. That broadly corresponds to exploring an electric power plant having up to 150 MW gross output during a period of 50 years.
These results show that geothermal energy and CO₂ storage, often portrayed as conflicting uses of the subsurface, can actually work together, enhancing the economic feasibility of each other in case mafic and/or ultramafic rock formations are used as reservoirs.

The world’s surface is clustered according to the centennial evolution of near surface temperature, using a continuous piecewise trend methodology applied to the GISS surface temperature data for the last 100 years. A spatial distribution of the timing of onset of local warming, alongside with the local decadal trends are presented and discussed. Time series of temperature, obtained by averaging only regions with the same temperature low frequency behaviour, are also presented and discussed. The world's globe surface is divided into 5 clusters defined by the surface trend temperature behaviour: (1) first and last period of warming having an cooling period in between (59% of the Earth surface), (2) later warming after a continuous cooling period (11% of the Earth surface), (3) later cooling after an initial warming period (9% of the Earth surface), (4) continuous warming (7.5% of the Earth surface) and (5) first and last periods of cooling having an warming period in between (5.4% of the Earth surface).

In the Iberian Peninsula (IP) the rise of temperatures during last decades has been noticeable, especially in spring and summer seasons. The aim of this study is to identify characteristic circulation types (CTs) conducive to the occurrence of warm extremes and to describe long-term changes both in circulation and in the percentage of associated extremes. A sample of 29 long station series of daily maximum (Tmax) and minimum (Tmin) temperature across the IP are considered for the study. Daily mean Sea Level Pressure reconstructions from the EMULATE project for the period 1850-2003 were classified into daily CTs using a simulated annealing clustering technique, separately for spring (MAM) and summer (JJA). The distinct CTs are examined for their tendency to give rise to daily temperature extremes at each specific location. Moreover, the existence of significant trends in the temporal frequency of the CTs is discussed, as well as their within type temporal variations in association to local extremes.

In both seasons, spring and summer, a warming signal has been detected in specific circulation types: especially in spring, an increasing incidence of high pressure conditions in the north of Iberia together with a warming of CTs indicating westerly and south-westerly flows explain the increase in warm days. In summer there is significant long-term positive trend in strong North Atlantic Anticyclone and Iberian thermal low-type patterns, but most of the warming has to be explained by within-type changes: the same CTs give rise to high temperatures more frequently, especially from around the 1970´s.

Short-term exposure to ozone is a public health concern worldwide. Tropospheric ozone is a secondary air pollutant, formed primarily through a complex series of photochemical reactions between nitrogen oxides and reactive hydrocarbons. Hot days with clear skies favour ozone production. Hence a warmer climate is likely to increase ozone ambient concentration and consequently the impact of ozone related health effects.

In this paper we present a statistical model that was developed using an additive mixed modelling approach to estimate daily ozone concentrations based on ground level climate variables, ozone precursors and synoptic atmosphere variables from the National Centre of Environmental Prediction. Two future scenarios (A2a and B2a) of daily ozone concentrations were obtained using the global circulation model (GCM) HadCM3 taking also into account local per capita ozone precursor’s emissions and population growth for each scenario.

This work is focused on the study of the total ozone column (TOC) trends over the Iberian Peninsula during the last 30 years (1979-2009). This analysis is carried out using satellite TOC data and it is divided into two sub-periods in order to detect changes in the ozone trend pattern: from 1979 to 1994 using the NASA Total Ozone Mapping Spectrometer (TOMS) and from 1995 to 2009 by means of the ESA Global Ozone Monitoring Experiment (GOME). The analysis of the long-term ozone trends is performed using annual mean time series derived from the average of the deseasonalized monthly TOC series. The results show that the ozone depletion was statically significant at the 95% confidence level during the first sub-period (1979-1994) in the entire region of study, with linear trends from -4.5 %/decade to -2.9 %/decade. These linear trends presented a clear dependence on latitude, being higher for the Northerner locations than for the Southerner. By contrast, the analysis of the second sub-period of study (1995-2009) presented positive ozone trends from +0.6 %/decade to +1.8 %/decade (only statically significant in four of nine locations of study), indicating that the ozone layer may be responding as expected to the controls on ozone-depleting substances imposed by the Montreal Protocol. Additionally, a seasonal trend analysis is performed using the average of the deseasonalized monthly values for each season of the year. The seasonal analysis showed that while the negative ozone trends during the first sub-period of study were statically significant in the springtime and summertime, the positive seasonal trends during the second sub-period did not show any statistically significance.

Lisbon is the largest urban area in the Western European coast. Due to this geographical position, the Atlantic Ocean is an important source of particles and plays an important role in many atmospheric processes. The main objectives of this work were 1) to perform a chemical characterization of PM_2.5 sampled in Lisbon, 2) to identify the main sources of particles and to determine their contribution to this urban area and 3) to assess the impact of maritime air mass trajectories on the concentration and composition of respirable particles sampled in Lisbon. During 2007, PM_2.5 was collected on a daily basis in the centre of Lisbon with a Partisol sampler. The exposed teflon filters were measured by gravimetry and were cut into two parts: one was analysed by Instrumental Neutron Activation Analysis and the other by Ion Chromatography. Principal Component Analysis and Multilinear Regression Analysis were used to identify possible sources of PM_2.5 and to determine their mass contribution. Five main groups of sources were identified: secondary aerosols, traffic, a source of calcium, soil and sea. Four days backward trajectories, ending in Lisbon, at the starting sampling time were calculated with the Hysplit Model. Results showed that maritime transport scenarios were very frequent. These episodes were characterized by a significant decrease of anthropogenic aerosol concentrations and had a significant role on the air quality from this urban area.

— This project aims at the application of the KLIMA inversion algorithm, optimally suited for CO₂ retrieval and integrated into the ESA GPOD (Grid Processing On-Demand) operational environment, to processing Level-1 data acquired by the IASI instrument onboard the METOP-A satellite and at the retrieval of carbon dioxide columns for comparison and cross-validation with GOSAT TANSO-FTS Level-2 data. The activities included in this study are: the adaptation of the KLIMA algorithm for the retrieval of CO₂ column from IASI spectra; a sensitivity assessment and evaluation of the performances of the optimized KLIMA-IASI code for CO₂ retrieval; the integration of the KLIMA-IASI inversion code on the ESA GRID-based operational environment G-POD (Grid Processing On-Demand); the processing of IASI Level 1 data using the KLIMA-IASI/G-POD retrieval code and a final comparison and cross validation of KLIMA-IASI CO₂ products along with GOSAT/TANSO-FTS operational products. For the performance of the retrieval a target accuracy of 0.3% (1 ppmv out of 370 ppmv) on regional scales (1000 x 1000 km) at monthly intervals was assumed as reference value. The KLIMA-IASI retrieval code integration on G-POD has been completed and is now available for bulk processing of IASI data to be compared with TANSO-FTS measurement products for validation purposes. The consolidated version of the KLIMA-IASI code on G-POD will be then made available to all interested users.

The last ten years have seen a particularly intense increase in the degree of emphasis to climate issues as a whole and in the level of attention paid to climate change in particular. Finding practical, workable and cost-efficient solutions to the problems posed by Climate Change is now a world priority and one which links government and non-government organisations as well as the general public in a way not seen before. But even though climate change is a matter of great scientific relevance and of broad general interest, there are many problems related to its communication.

The understanding about the causes, consequences and means to tackle climate change is one of the most important challenges of modern times. Without a holistic understanding of the problem and its various ramifications, there can be no effective handling of the problem, nor can long-term solutions be sought. This paper outlines the need for better information, networking and technology transfer on climate change. It describes the International Climate Change Information Programme (IICIP), as well as its activities and projects, which ultimately aim to support the on-going efforts towards the search for solutions for the problems associated with climate change, an issue which is global in nature, but which needs to be supported by concrete regional and local efforts.

Based on experiences gained in the frame of the climate project CELA funded in the context of the European Commission ALFA III Programme, this paper focuses on networking and technology transfer in the field of climate change between Latin America and Europe to illustrate how higher education institutions (HEI) can contribute to sustainable socio-economic development in Latin America. The paper will provide evidence for the fact that, despite the fact that many Latin American states have given climate change adaptation a high priority, the same states often have neither the technology nor the resources needed in order to adapt successfully. Also, to cope with the many challenges climate change poses, the role of HEIs, especially in terms of research, consultancy and technology transfer as well as the capacity-building and qualification of human capital within the HEI and beyond, will be explored further. Finally, the paper will introduce a university-industry networking project which fosters the transnational transfer of climate change technology between Europe and Latin America and concludes by indicating some emerging themes which ought to be tackled to foster adaptation to climate change in this region.

This paper is based on the experiences gained by “The Small Developing Island Renewable Energy Knowledge and Technology Transfer Network (DIREKT)”, which is a cooperation scheme involving universities from Germany, Fiji, Mauritius, Barbados, and Trinidad and Tobago, with the aim of strengthening science and technology capacity in the field of renewable energy of a sample of ACP (Africa, Caribbean, Pacific) small island developing states, by means of technology transfer, information exchange and networking. Developing countries are especially vulnerable to problems associated with climate change and much can be gained by raising their capacity in the field of renewable energy, which is a key area. The project is funded by the ACP Science and Technology Programme, an EU programme for cooperation between the European Union and the ACP region (Africa, Caribbean, Pacific). This paper discusses the contribution that can be made by renewable energy as a tool in addressing the challenge of climate change on a global level. It shows the extent to which renewable energy systems are being used in order to satisfy current energy demands and which positive effects have been achieved with these measures. The paper also discusses some of the empirical evidence available and outlines some of the actions currently being taken in the Pacific region. Finally, it summarises some of the lessons learned from the Pacific region and lists some of the challenges and measures that need to be implemented in order to achieve a better integration between the use of renewable energy and climate change goals in the Pacific region.

Essaouira synclinal area is part of the semi-arid areas of Morocco that are subject to the impact of climatic and human pressures. In the case of this coastal area, which includes two main aquifers superimposed; the Plio-Quaternary and Turonian, the resulting vulnerability is compounded by the risk of infiltration navy. The Rainfall in the area does not exceed 300 mm year^-1, the average temperature hovers around 20 ° C, the piezometric map of Essaouira synclinal basin was made, different water samples have been collected from October 2009 after exceptional rainfall, all waters are sodium-chloride facies, interpretation of mineralization indicates power by the Ksob Wadi in the northeast and increasing levels of chlorides in the central part generated by the Essaouira diaper hidden. Excessive levels of nitrates have been identified, as well as chlorides after rains of winter 2009. The electrical conductivity and concentrations of ₁₈O and ₂H were measured, a local meteoric water line was determined according to the Atlantic origin of precipitation. The Essaouira Basin is more vulnerable to drought because its climate is entirely dependent on recharge meteoric waters.

This paper describes the methodology and results from the analysis of climate scenarios and their impact on hydrometeorological variables and the energy system in the Metropolitan Region of Santiago, Chile´s capital city. Data are reported for historical and future scenarios. Meteorological data were obtained from meteorological stations and water resources administration, and GCM climate projections were obtained from globally available sources (A2-worst case and B1-best case scenarios). For future scenarios, a standard, simple downscaling methodology based on the probability distribution of each variable was used. A special study on the impact on the energy system was carried out. Overall results indicate that in the near future (2045-2065 period) Santiago will be a dryer, hotter city, with a high number of days with extreme temperatures, increased drought during the winter and summer, and lower life quality indexes derived from climate change effects. In the energy sector a decrease in the hydropower electricity is expected as well as a change in patterns of consumption with a shift in the peak demand, which will impose a growing stress on the longitudinal transmission network of the country.

Global warming will have far-reaching consequences for agriculture that will disproportionately affect poor and marginalized groups who depend on agriculture for their livelihoods and have a lower capacity to adapt. Sustainable food security in a world of growing population and changing diets is a major challenge under climate change. A recent study estimates the annual costs of adapting to climate change in the agricultural sector to be over US$ 7¬ billion. Agriculture and related activities also contribute to global warming with agriculture estimated to account for about a third of global GHG emissions. This paper makes the case for heightened focus on agriculture if the triple challenge of adaptation, mitigation and food security are going to be achieved. It suggests four key areas for research and action: understanding trade-offs amongst adaptation, mitigation and food security; implementing accelerated adaptation strategies; enhanced climate risk management; trialling and testing agricultural mitigation options that don't compromise food security. In the conclusions we call for a new “green agriculture”.