NASA Technical Reports Server (Ntrs) 20040111417: Global and Regional Decreases in Tropospheric Oxidants from Photochemical Effects of aerosols by NASA Technical Reports Server (Ntrs); published by
NASA Technical Reports Server (Ntrs) 20040111417: Global and Regional Decreases in Tropospheric Oxidants from Photochemical Effects of aerosols by NASA Technical Reports Server (Ntrs); published by
NASA Technical Reports Server (Ntrs) 19980211658: Pulmonary Deposition of aerosols in Microgravity by NASA Technical Reports Server (Ntrs); published by
NASA Technical Reports Server (Ntrs) 19980211658: Pulmonary Deposition of aerosols in Microgravity by NASA Technical Reports Server (Ntrs); published by
NASA Technical Reports Server (Ntrs) 20010083955: a Chronology of Annual-Mean Effective Radii of Stratospheric aerosols from Volcanic Eruptions During the Twentieth Century as Derived from Ground-Based Spectral Extinc...
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NASA Technical Reports Server (Ntrs) 20010083955: a Chronology of Annual-Mean Effective Radii of Stratospheric aerosols from Volcanic Eruptions During the Twentieth Century as Derived from Ground-Based Spectral Extinction Measurements by NASA Technical Reports Server (Ntrs); published by
aerosols emitted by landscape fires affect many climatic processes. Here, we combined an aerosol-climate model and a coupled climate-carbon model to study the carbon cycle and climate effects caused by fire-emitted ae...
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aerosols emitted by landscape fires affect many climatic processes. Here, we combined an aerosol-climate model and a coupled climate-carbon model to study the carbon cycle and climate effects caused by fire-emitted aerosols (FEA) forcing at the top of the atmosphere and at the surface. This forcing ('best guess' present-day values of -0.10 and -1.3 W m(-2) at the top of the atmosphere and surface, respectively) had a predominant cooling influence that altered regional land carbon stocks on decadal timescales by modifying vegetation productivity and soil-litter decomposition. Changes in regional land and ocean carbon stocks became much stronger for FEA forcing acting on multi-century timescales;this occurred because carbon stocks responded to the forcing itself on such timescales and also due to gradual effects on the climate (e.g. through increased sea ice cover) that further affected the carbon cycle. Carbon increases and decreases in different regions partly offset each other, so that absolute changes in global land, atmosphere, and ocean stocks were all < 2 Pg C after 30 years of FEA forcing and < 6 Pg C after more than 1000 years of FEA forcing. FEA-caused changes in land carbon storage did not substantially modify the magnitude of FEA emissions, suggesting there is no consequential regional-scale positive feedback loop between these two elements. However, we found indications that the FEA-caused cooling from frequently-burning regions in Africa and Australia increased land carbon stocks in eastern South America and equatorial Asia, respectively. This suggests the potential for remote carbon cycle effects from regions emitting large amounts of fire aerosols.
aerosols are found in a wide diversity of contexts and applications, including the atmosphere, pharmaceutics, and industry. aerosols are dispersions of particles in a gas, and the coupling of the two phases results in...
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aerosols are found in a wide diversity of contexts and applications, including the atmosphere, pharmaceutics, and industry. aerosols are dispersions of particles in a gas, and the coupling of the two phases results in highly dynamic systems where chemical and physical properties like size, composition, phase, and refractive index change rapidly in response to environmental perturbations. Aerosol particles span a wide range of sizes from 1 nm to tens of micrometres or from small molecular clusters that may more closely resemble gas phase molecules to large particles that can have similar qualities to bulk materials. However, even large particles with finite volumes exhibit distinct properties from the bulk condensed phase, due in part to their higher surface-to-volume ratio and their ability to easily access supersaturated solute states inaccessible in the bulk. aerosols represent a major challenge for study because of the facile coupling between the particle and gas, the small amounts of sample available for analysis, and the sheer breadth of operative processes. Time scales of aerosol processes can be as short as nanoseconds or as long as years. Despite their very different impacts and applications, fundamental chemical physics processes serve as a common theme that underpins our understanding of aerosols. This perspective article discusses challenges in the study of aerosols and highlights recent chemical physics advancements that have enabled improved understanding of these complex systems. (c) 2017 Author(s).
NASA Technical Reports Server (Ntrs) 19970020060: First Estimates of the Radiative Forcing of aerosols Generated from Biomass Burning Using Satellite Data by NASA Technical Reports Server (Ntrs); published by
NASA Technical Reports Server (Ntrs) 19970020060: First Estimates of the Radiative Forcing of aerosols Generated from Biomass Burning Using Satellite Data by NASA Technical Reports Server (Ntrs); published by
NASA Technical Reports Server (Ntrs) 20030014604: Raman Lidar Profiling of aerosols Over the Central US; Diurnal Variability and Comparisons with the Gocart Model by NASA Technical Reports Server (Ntrs); published by
NASA Technical Reports Server (Ntrs) 20030014604: Raman Lidar Profiling of aerosols Over the Central US; Diurnal Variability and Comparisons with the Gocart Model by NASA Technical Reports Server (Ntrs); published by
NASA Technical Reports Server (Ntrs) 19860001988: Generating aerosols for Laser Velocimeter Seeding by NASA Technical Reports Server (Ntrs); published by
NASA Technical Reports Server (Ntrs) 19860001988: Generating aerosols for Laser Velocimeter Seeding by NASA Technical Reports Server (Ntrs); published by
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