The objective of this project was to investigate the complex fracture of ice and understand its role within larger ice sheet simulations and global climate change. This objective was achieved by developing novel physics based models for ice, novel numerical tools to enable the modeling of the physics and by collaboration with the ice community experts. Fracture of ice is important in several fields of which the most visible and certainly the most significant is global warming. This has recently received international attention due to the collapse of some significant ice shelves. Ice fracture, however, is also important in other areas including oil and gas exploration and production within ice-infested waters, materials science research and length scales in ice, and microbiology. At the present time, ice fracture is not explicitly considered within ice sheet models due in part to large computational costs associated with the accurate modeling of this complex phenomena. However, fracture not only plays an extremely important role in regional behavior but also influences ice dynamics over much larger zones in ways that are currently not well understood. Dramatic illustrations of fracture-induced phenomena most notably include the recent collapse of ice shelves in Antarctica (e.g. partial collapse of the Wilkins shelf in March of 2008 and the diminishing extent of the Larsen B shelf from 1998 to 2002).

关键词：大气；气候变化；全球变暖

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This project was an initial effort to investigate the feasibility of an instrument combining real-time atmospheric particle composition measurements using an ATOFMS (Atmospheric Time-Of-Flight Mass Spectrometer) such as those performed by Prathers group at the University of California, San Diego (UCSD) with multi-wavelength scattering measurements of the type investigated by Sorensen et al., of Kansas State University (KSU). In this Phase I effort we proposed to investigate near-angle scattering and the possibility of integration of a multi-wavelength scattering instrument into the UCSD ATOFMS. After an initial optical design and calculations, we discovered issues with the theory of measurement and with mechanical integration. Evidence emerged that the method of multi-wavelength scattering is only efficacious for spherical particles, while most atmospheric particles are non-spherical fractal aggregates. We also determined that the integration of the detector into existing ATOFMS instruments would be severely limited by volume constraints, and additional volume would require prohibitive additional pumping compared with the existing ATOFMS systems. Based on this evidence, we decided not to pursue a Phase II effort.

关键词：大气；空气治理；空气污染

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The United Nations Intergovernmental Panel on Climate Change (IPCC) has stated that the warming of the climate system is unequivocal, as is now evident from observed increases in global average air and ocean temperatures, widespread melting of snow and ice and rising global average sea level. In the coming decades, it is expected that these changes will result in regional climate impacts, including, but not limited to, permafrost thawing, increased tropical cyclone intensity, shifting tropical storm tracks, and an increase in the frequency of heat waves and heavy precipitation. As a result of these findings, concern is growing both in the United States and abroad (47) that these changes will have serious adverse impacts on transportation and civil infrastructure systems unless agencies take proactive steps to mitigate these issues.

关键词：大气；气候变化；空气质量

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We have updated the Atmospheric Boundary Layer Environment (ABLE) model to use multicore/multinode parallelization via the Message Passing Interface (MPI). The model source code has been rewritten to use the Battlefield Environment Division Modeling Framework (BMF), an object-oriented framework developed to facilitate implementation of new technologies and algorithms. BMF is documented in this report.

关键词：大气；空气污染；空气治理模型

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Soils are a source of oxides of nitrogen (NO(sub x) = nitric oxide and nitrogen dioxide), precursors for the production of ozone (O(sub 3)), an air pollutant in the troposphere. Production of nitric oxide (NO) occurs through soil microbial processes using ammonium from nitrogen fertilizer and manure inputs or soil mineral nitrogen (N). Emissions of NO(sub x) were measured in almond, alfalfa, tomato, wheat, and silage corn cropping systems during summer months to obtain estimates of NO(sub x) emissions that could potentially be used in regional models predicting O(sub 3) in the San Joaquin Valley. The lowest average NO(sub x) fluxes (40 g NO(sub x)-N ha(sup -1) h(sup -1)) were measured. These high NOx flux events are difficult to predict.

关键词：大气；空气污染；空气治理

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The National Research Council convened a workshop on September 12-13, 2013, to review our current understanding and to discuss research needed to better understand proposed linkages. The workshop participants were encouraged to take a global perspective and consider the influence of the Arctic in the context of forcing from other components of the climate system, such as changes in the tropics, ocean circulation, and mid-latitude sea surface temperature.

关键词：大气；空气污染；空气治理；气候变化

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We are establishing a theoretical procedure to identify most potential candidates of CO2 solid sorbents from a large solid material databank to meet the DOE programmatic goal for energy conversion; To explore the optimal working conditions for the promised CO2 solid sorbents, especially from room to warm T ranges with optimal energy usage, used for both pre- and post-combustion capture technologies.

关键词：大气；温室气体；全球变暖

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A general outline of the ESPC coupled atmosphere/ocean/ice/wave/land prediction system is proposed for the Initial Operational Capability targeted for 2018. A description of how it will cycle at both FNMOC and NAVOCEANO is included, although the specifics of how the distributed job control will function are still to be determined as the system becomes more mature. A potential issue with regard to the transfer of model output between the two centers has been identified and must be addressed in the upcoming years.

关键词：大气；气候变化；空气治理

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Illinois Carbon Monoxide Screen for Intersection Modeling (COSIM) Version 3.0 is a Windows-based computer program currently used by the Illinois Department of Transportation (IDOT) to estimate worst-case carbon monoxide (CO) concentrations near signalized intersections in Illinois. Modeled results from COSIM are based on the U.S. Environmental Protection Agency's (EPA's) mobile source emission model, MOBILE6.2, and roadway dispersion model, CAL3QHC v 2.0. Emission factor (EF) tables derived from MOBILE6.2 are incorporated directly into COSIM's program coding. Recent regulatory changes in mobile source emissions modeling have prompted IDOT to update the EFs used in COSIM with EFs estimated using EPA's Motor Vehicle Emission Simulator (MOVES) mobile source emission model. This report documents the changes made to COSIM, Version 3.0, that allow IDOT to continue to use COSIM (Version 4.0) to estimate worst-case CO concentrations for proposed roadway projects with signalized intersections in 2013 and beyond.

关键词：大气；空气污染；空气质量检测

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The 2010 EPA emissions regulation for NOx is 0.2 g/bhr-hr, and the EPA has started to certify vehicles that can actually meet this regulation. Most manufacturers had initially opted instead to meet a Family Emission Limit (FEL) around 1.2-1.5 g/bhp-hr NOx with most of their vehicle emissions lying between the two standards. Currently the EPA has certified engines with both the Exhaust Gas Recirculation (EGR) and Selective Catalytic Reduction (SCR) technologies to meet the strict 0.2 g/bhr-hr NOx standard. While there is only one EGR system that has been certified by the EPA as meeting 2010 emissions regulations (Navistar, Inc.), there are several SCR systems that can meet this requirement (Cummins, Detroit Diesel, Volvo etc.). Moreover the SCR system in addition to meeting emissions regulations can result in a 3 to 5.5% increase in fuel efficiency. The SCR system typically uses a zeolite NOx adsorption catalyst that can selectively adsorb NOx molecules during lean burn operation and convert it to N2 and H2O with the injection of an urea water solution called Diesel Exhaust Fluid (DEF). It is the technology of choice for emissions control in Europe and several manufacturers have adopted this for the United States. SCR systems require tuning to work properly and systems can be tuned with either preexisting engine performance curves or with NOx/NH3 sensors. The use of NOx/NH3 sensors can provide closed loop control of the SCR system that can optimize the system for improved NOx reduction efficiencies and low NH3 slip. According to a recent review Reliable and accurate NOx sensors will be the key to the management of adsorption catalysts. The optimized use of SCR systems can increase the value for the customer with fuel and DEF savings (including reduced frequency and costs of the dealer servicing of the emissions system consumables) over the life of the vehicle helping defray the added cost of the system.

关键词：大气；废气排放；废气转化处理；大气污染

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