One study reports that the influence of negative radiative forcing due to emissions from on-road transport is much lower than for the power generation sector in both the United States and globally GWPs are a valuable tool to compare Hydraulic research paper radiative forcing of different gases but are not sufficient when thinking about fuel-switching scenarios.
Recently, Wigley concluded that coal-to-gas switching on a global scale would result in increased warming on a global scale in the short term, based on examining a set of scenarios with a climate model that included both the increased warming produced by CH4 losses from the natural gas fuel cycle and the additional cooling that occurs due to SO2 emissions and the sulfate aerosols they form as a result of burning coal 5.
The three curves within each frame follow the conventions outlined in Fig. This assumption deserves much further scrutiny. Much work needs to be done to determine actual emissions with certainty and to accurately characterize the site-to-site variability in emissions.
The production of sulfur aerosols as a result of coal combustion causes such negative impacts on human and ecosystem health that it is prudent to assume that policies will continue to be rapidly implemented in many, if not Hydraulic research paper, countries to reduce such emissions at a much faster pace than assumed by Wigley.
Methods Our approach of using TWPs to compare the cumulative radiative forcing of fuel-technology combinations is a straightforward extension of the calculation of GWP, which is given by Eq.
Little work appears to have been done to evaluate fuel-switching in on-road transportation with methods that consider the implications of all climate forcing emissions, including sulfur aerosols and black carbon, although the effect of short-lived climate forcers on individual transport sectors has been studied 16 TWPs provide a transparent, policy-relevant analytical approach to examine the time-dependent climate influence of different fuel-technology choices.
While CH4 leakage from natural gas infrastructure and use remains uncertain, it appears that current leakage rates are higher than previously thought.
Specific challenges include confirming the primary sources of emissions and determining drivers of variance in leakage rates. Significant progress appears possible given the economic benefits of capturing and selling lost natural gas and the availability of proven technologies.
We label as Technology-1 the alternative that combusts natural gas and has CO2 emissions E1,CO2 and CH4 emissions from the production, processing, storage, delivery, and use of the fuel: If LREF is the percent of gross natural gas produced that is currently emitted to the atmosphere over the relevant fuel cycle e.
When leak rates are less than the y-intercept, a fuel switch scenario would result in net climate benefits beginning immediately. Because CH4 initially has a much higher effect on radiative forcing than CO2, maintaining low rates of CH4 leakage is critical to maximizing the climate benefits of natural gas fuel-technology pathways.
We emphasize that our calculations assume an average leakage rate for the entire U. Considering streams of emissions is more reflective of real-world scenarios that involve activities that occur over multiyear time frames.
Ensuring a high degree of confidence in the climate benefits of natural gas fuel-switching pathways will require better data than are available today. For A and B, the maximum leakage is the sum of losses from the well through the distribution system plus losses from the CNG vehicle itself well-to-wheels ; for C, the maximum leakage is from the well through the transmission system where most power plants receive their fuel.
Increasingly, this will also be the case globally.
However, given limited current evidence, it is likely that leakage at individual natural gas well sites is high enough, when combined with leakage from downstream operations, to make the total leakage exceed the 3.
This implies that our approach, which considers CO2 and CH4 emissions alone, provides a reasonable first-order estimate of changes in radiative forcing from fuel-switching scenarios for the on-road transport sector.
Accounting for the lower SO2 from U. Improved Science and Data Are Needed. Greater direct involvement of the scientific community could help improve estimates of CH4 leakage and identify approaches that enable independent validation of industry-reported emissions.
This means that by the projected sulfur emissions from the U. Plotting the entire curve enables one to see the GWP values for all time horizons.Methane Emissions: from blind spot to spotlight. The environmental impact of methane emissions – which come from a wide range of natural and anthropogenic sources – has received growing attention.
AWARDS Hans Albert Einstein Award Congratulations to Thanos Papanicolaou, Ph.D., mi-centre.com, Chief Editor of the Journal of Hydraulic Engineering, for receiving Hans Albert Einstein Award.
Paper SPE Nov. Print. 10 Hydraulic Fracturing Goes to Court, supra at note 8. 11 Hydraulic Fracturing Research Study, supra at note 7.
Writing final research paper fracking Katie Schlagenhaft English Laura Moran 2 December Fracking in Pennsylvania Hydraulic fracturing, also known as fracking, is damaging our watersheds and for some of us, fracking sites are in our own backyards.
Impact Factor. Research paper. Article. Experimental validation of the admittance matrix method on a Y-system.
Through-water terrestrial laser scanning in hydraulic scale models: proof .Download