Browsing by Subject "CO2"
Now showing 1 - 7 of 7
Results Per Page
Sort Options
Item Open Access A Review of the Massachusetts Regulated Waste Disposal Industries Focusing on Transportation Emissions(2020-04-20) Wood, StefanieTransportation of regulated waste generates significant greenhouse gas (GHG) emissions. Reductions in the number of disposal locations in Massachusetts due to industry consolidation force wastes to be transported farther for proper handling, increasing vehicular emissions. Previous studies of freight emissions have focused on mitigating GHG emissions through technological modifications of vehicles, use of alternative fuels, and maximizing the efficiency of transportation routes through hub siting. This study tracks changes in CO2 emissions by focusing on changes in destination locations. By calculating distances and CO2 emissions from generation to disposal locations over a ten-year period, trends caused by disposal industry contraction are identified. This information is critical for planning how regulated wastes can and will be managed in the future to minimize CO2 emissions (a GHG mitigation priority) balanced against land use concerns.Item Open Access Analyze China's CO2 Emission Pattern and Forecast Its Future Emission(2009-08-28T13:47:02Z) Sun, XiaojingGreenhouse gas emission from China is projected to exceed that from the U.S. according to the widely cited paper Forecasting the Path of China’s CO2 Emissions Using Province Level Information, published by Professor Auffhammer and Carson from UC Berkeley. This conclusion has important implications on international relations and strategies in combating global climate change. The current work examines the statistical basis of this projection. The results suggest that the conclusion is potentially flawed for the following two reasons. First, the model proposed by Auffhammer and Carson assumes a common relationship between CO2 emission and GDP growth for all 30 provinces over the study period. Second, the preferred models in Auffhammer and Carson’s work failed to properly address time dependence in data. The two structural errors in the models will potentially lead to biased predictions because the models’ incorrectly handled data and model error. The current study developed models that corrected the two model error structure issues in UC Berkeley’s paper. These models result in different CO2 emission trajectory from the ones predicted by Auffhammer and Carson.Item Open Access Economics of Direct Air Capture of Carbon Dioxide(2020-04-20) Laska, Caryn; Cortes, VeronicaThis Masters Project was designed to review Direct Air Capture (DAC) technology’s current positioning in the market and to pinpoint necessary augmentations to economics and policy that must take place in order to improve that positioning. The underlying problem DAC was designed to solve was climate change, which by economists' standards is considered an externality and not a challenge that directly impacts society’s buying/selling behaviors. We recommend, with this paper, various ways the equation could hypothetically change for which the DAC solution becomes relevant. While the underpinning of our thesis is that improving environmental outcomes by capturing more CO2 emissions is advantageous for our planet’s future, the critical reason for defining market conditions that demand DAC technologies is that concerns of climate change simply aren’t enough to encourage the advancement of the space. Our approach to researching this question is to conduct literature reviews, interviews, and to analyze data sets to determine best fit solutions for stimulating demand for DAC technologies in the market. Through our research, we concluded a number of market scenarios and assumptions that would help the take-off of this technology but the most resounding impact on the space will come from policy solutions.Item Open Access Emission Trajectories of BC Compared to CO2 and SO2 Based on Global Country-level Emission Inventories(2016-04-29) Ru, MuyeBlack carbon (BC), as an essential component of particulate matters causing air pollution, has been recently recognized as the second largest contributor to global warming. The emission trajectory of BC with increase of income and the determinants of it are studied in this project, with analysis in different sectors and regions. It shows that BC developed a unique pattern of emission trajectories dominated by the mixture of fuel switch in residential sector and demand growth in transportation sector. This contrasts the typical understanding of Environmental Kuznets Curve (EKC) trajectories for air pollutants and greenhouse gases, which have been heavily studied in the forms of SO2 and CO2 respectively. Based on the same inventory, emission trajectories with income for CO2, SO2, and BC are compared, with CO2 and SO2 fitted with quadratic EKC. Based on the depicted emission trajectories of countries in power, industrial, residential, and transportation sectors, analysis are led on the effectiveness of regulation, influences of natural resources, and the relationship with different developmental patterns.Item Open Access Expanding the Life Cycle Analysis Boundaries for Corn-based Ethanol to Include Land-Use Change: Implications for Greenhouse Gas Emissions(2007-08-27T13:59:13Z) Bolcar, KathleenCurrent life cycle analyses of corn-based ethanol assume that CO2 fluxes from soils are negligible. This paper asks if it is necessary to include this flux for corn grown on lands previously enrolled in the Conservation Reserve Program. The analysis shows that CO2 fluxes from soils is indeed an important variable to consider when determining the overall impact of corn-based ethanol on greenhouse gas emissions.Item Open Access Inorganic carbon speciation and fluxes in the Congo River(Geophysical Research Letters, 2013-02-16) Wang, ZA; Bienvenu, DJ; Mann, PJ; Hoering, KA; Poulsen, JR; Spencer, RGM; Holmes, RMSeasonal variations in inorganic carbon chemistry and associated fluxes from the Congo River were investigated at Brazzaville-Kinshasa. Small seasonal variation in dissolved inorganic carbon (DIC) was found in contrast with discharge-correlated changes in pH, total alkalinity (TA), carbonate species, and dissolved organic carbon (DOC). DIC was almost always greater than TA due to the importance of CO2*, the sum of dissolved CO2 and carbonic acid, as a result of low pH. Organic acids in DOC contributed 11-61% of TA and had a strong titration effect on water pH and carbonate speciation. The CO2* and bicarbonate fluxes accounted for ~57% and 43% of the DIC flux, respectively. Congo River surface water released CO2 at a rate of ~109 mol m-2 yr-1. The basin-wide DIC yield was ~8.84 × 104 mol km-2 yr-1. The discharge normalized DIC flux to the ocean amounted to 3.11 × 1011 mol yr-1. The DOC titration effect on the inorganic carbon system may also be important on a global scale for regulating carbon fluxes in rivers. Key Points The carbonate chemistry near the Congo River mouth is comprehensively studied Organic acids have a titration effect on the inorganic carbon system Surface CO2 and inorganic carbon fluxes to the ocean are characterized ©2013. American Geophysical Union. All Rights Reserved.Item Open Access Stratigraphic and Earth System approaches to defining the Anthropocene(Earth's Future, 2016-08-01) Steffen, W; Leinfelder, R; Zalasiewicz, J; Waters, CN; Williams, M; Summerhayes, C; Barnosky, AD; Cearreta, A; Crutzen, P; Edgeworth, M; Ellis, EC; Fairchild, IJ; Galuszka, A; Grinevald, J; Haywood, A; Ivar do Sul, J; Jeandel, C; McNeill, JR; Odada, E; Oreskes, N; Revkin, A; Richter, DDB; Syvitski, J; Vidas, D; Wagreich, M; Wing, SL; Wolfe, AP; Schellnhuber, HJ© 2016 The Authors. Stratigraphy provides insights into the evolution and dynamics of the Earth System over its long history. With recent developments in Earth System science, changes in Earth System dynamics can now be observed directly and projected into the near future. An integration of the two approaches provides powerful insights into the nature and significance of contemporary changes to Earth. From both perspectives, the Earth has been pushed out of the Holocene Epoch by human activities, with the mid-20th century a strong candidate for the start date of the Anthropocene, the proposed new epoch in Earth history. Here we explore two contrasting scenarios for the future of the Anthropocene, recognizing that the Earth System has already undergone a substantial transition away from the Holocene state. A rapid shift of societies toward the UN Sustainable Development Goals could stabilize the Earth System in a state with more intense interglacial conditions than in the late Quaternary climate regime and with little further biospheric change. In contrast, a continuation of the present Anthropocene trajectory of growing human pressures will likely lead to biotic impoverishment and a much warmer climate with a significant loss of polar ice.