Correlation of Global Warming Potential and Atmospheric Life Times of Halocarbons

Author(s):  
Suman Kumar Sharma

Sustainability of life form on the earth is a major concern of every nation, which stems from the continued global warming trend, which has become a major policy, political, and economic issue. Global warming is the most important challenge thrown by the human activities largely due to rapid pace of industrialization in the twenty first century. The impact is likely to extend to next few centuries and unless controlled there would be irrevocable damage to the life form on this planet. Human made halocarbons have a high global warming potential, and some still have the potential to cause damage to the ozone layer as well if released to the atmosphere. The implications of global warming have far-reaching effects beyond the imagination of common person. Rise in global temperature, rise in sea level, food shortages, large scale spread of diseases & infections, catastrophic economic consequences and colossal loss of bio-diversity are some of the major implications of global warming trend. Although many methods are in vogue for comparison of impact of global warming of different compounds, yet the concept of Global warming potential with reference to Carbon dioxide is the simplest one and is widely used. An endeavor has been made in this paper to correlate and develop empirical relations of global warming potential and atmospheric lifetimes of Halocarbons. A new parameter Glife has been evolved for this purpose.

1993 ◽  
Vol 69 (3) ◽  
pp. 290-293 ◽  
Author(s):  
Brian J. Stocks

The looming possibility of global warming raises legitimate concerns for the future of the forest resource in Canada. While evidence of a global warming trend is not conclusive at this time, governments would be wise to anticipate, and begin planning for, such an eventuality. The forest fire business is likely to be affected both early and dramatically by any trend toward warmer and drier conditions in Canada, and fire managers should be aware that the future will likely require new and innovative thinking in forest fire management. This paper summarizes research activities currently underway to assess the impact of global warming on forest fires, and speculates on future fire management problems and strategies.


2008 ◽  
Vol 21 (22) ◽  
pp. 6052-6059 ◽  
Author(s):  
B. Timbal ◽  
P. Hope ◽  
S. Charles

Abstract The consistency between rainfall projections obtained from direct climate model output and statistical downscaling is evaluated. Results are averaged across an area large enough to overcome the difference in spatial scale between these two types of projections and thus make the comparison meaningful. Undertaking the comparison using a suite of state-of-the-art coupled climate models for two forcing scenarios presents a unique opportunity to test whether statistical linkages established between large-scale predictors and local rainfall under current climate remain valid in future climatic conditions. The study focuses on the southwest corner of Western Australia, a region that has experienced recent winter rainfall declines and for which climate models project, with great consistency, further winter rainfall reductions due to global warming. Results show that as a first approximation the magnitude of the modeled rainfall decline in this region is linearly related to the model global warming (a reduction of about 9% per degree), thus linking future rainfall declines to future emission paths. Two statistical downscaling techniques are used to investigate the influence of the choice of technique on projection consistency. In addition, one of the techniques was assessed using different large-scale forcings, to investigate the impact of large-scale predictor selection. Downscaled and direct model projections are consistent across the large number of models and two scenarios considered; that is, there is no tendency for either to be biased; and only a small hint that large rainfall declines are reduced in downscaled projections. Among the two techniques, a nonhomogeneous hidden Markov model provides greater consistency with climate models than an analog approach. Differences were due to the choice of the optimal combination of predictors. Thus statistically downscaled projections require careful choice of large-scale predictors in order to be consistent with physically based rainfall projections. In particular it was noted that a relative humidity moisture predictor, rather than specific humidity, was needed for downscaled projections to be consistent with direct model output projections.


2007 ◽  
Vol 4 (2) ◽  
pp. 1059-1092 ◽  
Author(s):  
S. Lehuger ◽  
B. Gabrielle ◽  
E. Larmanou ◽  
P. Laville ◽  
P. Cellier ◽  
...  

Abstract. Nitrous oxide, carbon dioxide and methane are the main biogenic greenhouse gases (GHG) contributing to the global warming potential (GWP) of agro-ecosystems. Evaluating the impact of agriculture on climate thus requires a capacity to predict the net exchanges of these gases in an integrated manner, as related to environmental conditions and crop management. Here, we used two year-round data sets from two intensively-monitored cropping systems in northern France to test the ability of the biophysical crop model CERES-EGC to simulate GHG exchanges at the plot-scale. The experiments involved maize and rapeseed crops on a loam and rendzina soils, respectively. The model was subsequently extrapolated to predict CO2 and N2O fluxes over an entire crop rotation. Indirect emissions (IE) arising from the production of agricultural inputs and from cropping operations were also added to the final GWP. One experimental site (involving a wheat-maize-barley rotation on a loamy soil) was a net source of GHG with a GWP of 350 kg CO2-C eq ha−1 yr−1, of which 75% were due to IE and 25% to direct N2O emissions. The other site (involving an oilseed rape-wheat-barley rotation on a rendzina) was a net sink of GHG for –250 kg CO2-C eq ha−1 yr−1, mainly due to a higher predicted C sequestration potential and C return from crops. Such modelling approach makes it possible to test various agronomic management scenarios, in order to design productive agro-ecosystems with low global warming impact.


Energies ◽  
2019 ◽  
Vol 13 (1) ◽  
pp. 80 ◽  
Author(s):  
Ricardo Ramírez-Villegas ◽  
Ola Eriksson ◽  
Thomas Olofsson

The aim of this study is to assess how the use of fossil and nuclear power in different renovation scenarios affects the environmental impacts of a multi-family dwelling in Sweden, and how changes in the electricity production with different energy carriers affect the environmental impact. In line with the Paris Agreement, the European Union has set an agenda to reduce greenhouse gas emissions by means of energy efficiency in buildings. It is estimated that by the year 2050, 80% of Europe’s population will be living in buildings that already exist. This means it is important for the European Union to renovate buildings to improve energy efficiency. In this study, eight renovation scenarios, using six different Northern European electricity mixes, were analyzed using the standard of the European Committee for Standardization for life cycle assessment of buildings. This study covers all life cycle steps from cradle to grave. The renovation scenarios include combinations of photovoltaics, geothermal heat pumps, heat recovery ventilation, and improvement of the building envelope. The results show that while in some electricity mixes a reduction in the global warming potential can be achieved, it can be at the expense of an increase in radioactive waste production, and, in mixes with a high share of fossil fuels, the global warming potential of the scenarios increases with time, compared with that of the original building. It also shows that in most electricity mixes, scenarios that reduce the active heat demand of the building end up in reducing both the global warming potential and radioactive waste, making them less sensitive to changes in the energy system.


2020 ◽  
Author(s):  
Pedro M. Sousa ◽  
Alexandre M. Ramos ◽  
Ricardo M. Trigo ◽  
Christoph C. Raible ◽  
Martina Messmer ◽  
...  

<p>Moisture transport and Atmospheric Rivers (ARs) over the Northeastern Atlantic are a very relevant process for the inter-annual variability of precipitation over Western Europe. Based on a long-term transient simulation (850-2100CE) from the CESM model, we have showed that moisture transport towards Western Europe (using the vertically integrated horizontal water vapor transport, IVT) has been increasing significantly since pre-industrial period, in a clear association with the global warming trend. Both current and projected changes (using RCP 8.5) significantly exceed the range given by inter-annual to inter-decadal internal/external variability observed during the last millennium.</p><p>We have checked the emergence of the temperature, IVT and precipitation signals in Iberia and the UK, showing that while the first two have now clearly emerged from the pre-warming state, precipitation series are still slightly below that threshold. Nevertheless, projections clearly show an increase in rainfall at higher latitudes (i in phase with a warmer and moister atmosphere); and a decrease at lower latitudes decoupled from the overall increase in moisture availability. Additionally we have explored the role played by large-scale circulation and atmospheric dynamics for these contrasting projections. Overall, results show that a poleward migration of moisture corridors and ARs explain a significant fraction of these projected trends. Based on the Clausius–Clapeyron relation we have separated the thermodynamical from dynamical changes. We also show how that a significant increase in subtropical anticyclonic activity over Iberia is responsible for: i) dynamical circulation changes; ii) a shortening of the wet season; iii) to less efficient precipitation regimes in the region. These results highlight the urge to adapt to a drying trend in Mediterranean-type climates, as a consequence of Global Warming.</p><p> </p><p>The financial support for this work was possible through the following FCT project: HOLMODRIVE - North Atlantic Atmospheric Patterns influence on Western Iberia Climate: From the Lateglacial to the Present [PTDC/CTA-GEO/29029/2017]</p>


2018 ◽  
Author(s):  
Brett McPherson ◽  
Mihray Sharip ◽  
Terry Grimmond

Background. Sustainable purchasing can reduce greenhouse gas (GHG) emissions at healthcare facilities (HCF). A previous study found that converting from disposable to reusable sharps containers (DSC, RSC) reduced sharps waste stream GHG by 84% but, in finding transport distances impacted significantly on GHG outcomes, recommended further studies where transport distances are large. This case-study examines the impact on GHG of nation-wide transport distances when a large US health system converted from DSC to RSC. Methods. The study examined the alternate use of DSC and RSC at a large US university hospital where: the source of polymer was distant from the RSC manufacturing plant; both manufacturing plants were over 3,000 km from the HCF; and the RSC disposal plant was considerably further from the HCF than was the DSC disposal plant. Using a “cradle to grave” life cycle assessment (LCA) tool we calculated annual GHG emissions (CO2, CH4, N2O) in metric tonnes of carbon dioxide equivalents (MTCO2eq) to assess the impact on global warming potential (GWP) of each container system. Primary energy input data was used wherever possible and region-specific impact conversions used to calculate GWP of each activity over a 12-month period. Unit process GHG were collated into Manufacture, Transport, Washing, and Treatment & disposal. Emission totals were workload-normalized and analysed using CHI2 test with P ≤0.05 and rate ratios at 95% CL. Results. The hospital reduced its annual GWP by 168 MTCO2eq (-64.5%; p < 0.001), and annually eliminated 50.2 tonnes of plastic DSC and 8.1 tonnes of cardboard from the sharps waste stream. Of the plastic eliminated, 31.8 tonnes were diverted from landfill and 18.4 from incineration. Discussion. Unlike GHG reduction strategies dependent on changes in staff behaviour (waste segregation, recycling, turning off lights, car-pooling, etc), purchasing strategies can enable immediate, sustainable and institution-wide GHG reductions to be achieved. Medical waste containers contribute significantly to the supply chain carbon footprint and, although non-sharp medical waste volumes have decreased significantly with avid segregation, sharps wastes have increased, and can account for 50% of total medical waste volume. Thus converting from DSC to RSC can assist reduce the GWP footprint of the medical waste stream. This study confirmed that large transport distances between polymer manufacturer and container manufacturer; container manufacturer and user; and/or between user and processing facilities, can significantly impact the GWP of sharps containment systems. However, even with large transport distances, we found that a large university health system significantly reduced the GWP of their sharps waste stream by converting from DSC to RSC.


2018 ◽  
Author(s):  
Brett McPherson ◽  
Mihray Sharip ◽  
Terry Grimmond

Background. Sustainable purchasing can reduce greenhouse gas (GHG) emissions at healthcare facilities (HCF). A previous study found that converting from disposable to reusable sharps containers (DSC, RSC) reduced sharps waste stream GHG by 84% but, in finding transport distances impacted significantly on GHG outcomes, recommended further studies where transport distances are large. This case-study examines the impact on GHG of nation-wide transport distances when a large US health system converted from DSC to RSC. Methods. The study examined the alternate use of DSC and RSC at a large US university hospital where: the source of polymer was distant from the RSC manufacturing plant; both manufacturing plants were over 3,000 km from the HCF; and the RSC disposal plant was considerably further from the HCF than was the DSC disposal plant. Using a “cradle to grave” life cycle assessment (LCA) tool we calculated annual GHG emissions (CO2, CH4, N2O) in metric tonnes of carbon dioxide equivalents (MTCO2eq) to assess the impact on global warming potential (GWP) of each container system. Primary energy input data was used wherever possible and region-specific impact conversions used to calculate GWP of each activity over a 12-month period. Unit process GHG were collated into Manufacture, Transport, Washing, and Treatment & disposal. Emission totals were workload-normalized and analysed using CHI2 test with P ≤0.05 and rate ratios at 95% CL. Results. The hospital reduced its annual GWP by 168 MTCO2eq (-64.5%; p < 0.001), and annually eliminated 50.2 tonnes of plastic DSC and 8.1 tonnes of cardboard from the sharps waste stream. Of the plastic eliminated, 31.8 tonnes were diverted from landfill and 18.4 from incineration. Discussion. Unlike GHG reduction strategies dependent on changes in staff behaviour (waste segregation, recycling, turning off lights, car-pooling, etc), purchasing strategies can enable immediate, sustainable and institution-wide GHG reductions to be achieved. Medical waste containers contribute significantly to the supply chain carbon footprint and, although non-sharp medical waste volumes have decreased significantly with avid segregation, sharps wastes have increased, and can account for 50% of total medical waste volume. Thus converting from DSC to RSC can assist reduce the GWP footprint of the medical waste stream. This study confirmed that large transport distances between polymer manufacturer and container manufacturer; container manufacturer and user; and/or between user and processing facilities, can significantly impact the GWP of sharps containment systems. However, even with large transport distances, we found that a large university health system significantly reduced the GWP of their sharps waste stream by converting from DSC to RSC.


2021 ◽  
Vol 8 ◽  
Author(s):  
María del Carmen Jiménez-Quiroz ◽  
Francisco Javier Barrón-Barraza ◽  
Rafael Cervantes-Duarte ◽  
René Funes-Rodríguez

This study presents an overview of bivalve assemblages in Bahia Magdalena (BM, México) and the possible impact of environmental variability on these populations, constantly stressed by fishing. This lagoon is responsible for a high proportion of harvest of regional bivalves. First, we list the bivalve species reported in public biogeographic databases. Based on eight commercially exploited species, we described the composition of the bivalve assemblage and its biological characteristics, the history of fishery, and environmental variability in the marine area adjacent to the lagoon (1970–2019) and the habitat of bivalves (2002–2020). Sources of data were public databases and published literature. The enlisted species (n = 184) belong to six orders, and most are small and infaunal, but the structure of the assemblage is unknown. The fisheries began at different times and focused on the most valuable resources. Almost all harvest of bivalves had wide variations because of intensive fishing and a weak regulation frame. After 2015, the main resources were the Pacific wing-oyster (a new resource since 2017) and the geoduck clam due to the declining abundance of other resources (e.g., pen shells, Pacific calico scallop). There was a warming trend in the region since the 1970's, but the strongest El Niño-Southern Oscillation (ENSO) phases caused the most notable changes before 2013; after that year, a combination of large-scale phenomena increased the temperature significantly. The trend of chlorophyll-a abundance negatively correlated with temperature, but there was an almost constant supply of particulate organic matter in the interior of Bahia Magdalena (BM). After 2015, the quality of lagoon water gradually deteriorated, and in 2017 and 2019, harmful algal blooms developed, but the impact was not fully assessed. The challenges faced by the fishery are multiple (institutional weakness and regional warming); however, permanent monitoring programs of environmental conditions and critical biological variables should be implemented to design scenarios that allow fishery sustainability.


Energies ◽  
2019 ◽  
Vol 12 (13) ◽  
pp. 2535 ◽  
Author(s):  
Rui Pacheco ◽  
Carla Silva

In Europe, ethanol is blended with gasoline fuel in 5 or 10% volume (E5 or E10). In USA the blend is 15% in volume (E15) and there are also pumps that provide E85. In Brazil, the conventional gasoline is E27 and there are pumps that offer E100, due to the growing market of flex fuel vehicles. Bioethanol production is usually by means of biological conversion of several biomass feedstocks (first generation sugar cane in Brazil, corn in the USA, sugar beet in Europe, or second-generation bagasse of sugarcane or lignocellulosic materials from crop wastes). The environmental sustainability of the bioethanol is usually measured by the global warming potential metric (GWP in CO2eq), 100 years time horizon. Reviewed values could range from 0.31 to 5.55 gCO2eq/LETOH. A biomass-to-ethanol industrial scenario was used to evaluate the impact of methodological choices on CO2eq: conventional versus dynamic Life Cycle Assessment; different impact assessment methods (TRACI, IPCC, ILCD, IMPACT, EDIP, and CML); electricity mix of the geographical region/country for different factory locations; differences in CO2eq factor for CH4 and N2O due to updates in Intergovernmental Panel on Climate Change (IPCC) reports (5 reports so far), different factory operational lifetimes and future improved productivities. Results showed that the electricity mix (factory location) and land use are the factors that have the greatest effect (up to 800% deviation). The use of the CO2 equivalency factors stated in different IPCC reports has the least influence (less than 3%). The consideration of the biogenic emissions (uptake at agricultural stage and release at the fermentation stage) and different allocation methods is also influential, and each can make values vary by 250%.


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