Download or read book Optical Properties and Radiative Forcing of Southern African Biomass Burning Aerosol written by Brian Indrek Magi and published by . This book was released on 2006 with total page 360 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Radiative Properties and Direct Effect of Southern African Biomass Burning Aerosols written by Steven John Abel and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Global Biomass Burning written by Joel S. Levine and published by MIT Press. This book was released on 1991 with total page 612 pages. Available in PDF, EPUB and Kindle. Book excerpt: This comprehensive volume is the first to consider biomass burning as a global phenomenon and to assess its impact on the atmosphere, on climate, and on the biosphere itself.
Download or read book Optical Closure for an Aerosol Column written by Ulrich Schumann and published by . This book was released on 2001 with total page 15 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Determination of the Single Scattering Albedo and Direct Radiative Forcing of Biomass Burning Aerosol with Data from the MODIS moderate Resolution Imaging Spectroradiometer Satellite Instrument written by Li Zhu and published by . This book was released on 2013 with total page 382 pages. Available in PDF, EPUB and Kindle. Book excerpt: Biomass burning aerosols absorb and scatter solar radiation and therefore affect the energy balance of the Earth-atmosphere system. The single scattering albedo (SSA), the ratio of the scattering coefficient to the extinction coefficient, is an important parameter to describe the optical properties of aerosols and to determine the effect of aerosols on the energy balance of the planet and climate. Aerosol effects on radiation also depend strongly on surface albedo. Large uncertainties remain in current estimates of radiative impacts of biomass burning aerosols, due largely to the lack of reliable measurements of aerosol and surface properties. In this work we investigate how satellite measurements can be used to estimate the direct radiative forcing of biomass burning aerosols. We developed a method using the critical reflectance technique to retrieve SSA from the Moderate Resolution Imaging Spectroradiometer (MODIS) observed reflectance at the top of the atmosphere (TOA). We evaluated MODIS retrieved SSAs with AErosol RObotic NETwork (AERONET) retrievals and found good agreements within the published uncertainty of the AERONET retrievals. We then developed an algorithm, the MODIS Enhanced Vegetation Albedo (MEVA), to improve the representations of spectral variations of vegetation surface albedo based on MODIS observations at the discrete 0.67, 0.86, 0.47, 0.55, 1.24, 1.64, and 2.12 μm channels. This algorithm is validated using laboratory measurements of the different vegetation types from the Amazon region, data from the Johns Hopkins University (JHU) spectral library, and data from the U.S. Geological Survey (USGS) digital spectral library. We show that the MEVA method can improve the accuracy of flux and aerosol forcing calculations at the TOA compared to more traditional interpolated approaches. Lastly, we combine the MODIS retrieved biomass burning aerosol SSA and the surface albedo spectrum determined from the MEVA technique to calculate TOA flux and aerosol direct radiative forcing over the Amazon region and compare it with Clouds and the Earth's Radiant Energy System (CERES) satellite results. The results show that MODIS based forcing calculations present similar averaged results compared to CERES, but MODIS shows greater spatial variation of aerosol forcing than CERES. Possible reasons for these differences are explored and discussed in this work. Potential future research based on these results is discussed as well.
Download or read book Modeling the Spectral Optical Properties of Ammonium Sulfate and Biomass Burning Aerosols written by and published by . This book was released on 2001 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The importance of including the global and regional radiative effects of aerosols in climate models has increasingly been realized. Accurate modeling of solar radiative forcing due to aerosols from anthropogenic sulfate and biomass burning emissions requires adequate spectral resolution and treatment of spatial and temporal variability. The variation of aerosol spectral optical properties with local relative humidity and dry aerosol composition must be considered. Because the cost of directly including Mie calculations within a climate model is prohibitive, parameterizations from offline calculations must be used. Starting from a log-normal size distribution of dry ammonium sulfate, we developed optical properties for tropospheric sulfate aerosol at 15 relative humidities up to 99 percent. The resulting aerosol size distributions were then used to calculate bulk optical properties at wavelengths between 0.175[micro]m and 4[micro]m. Finally, functional fits of optical properties were made for each of 12 wavelength bands as a function of relative humidity. Significant variations in optical properties occurred across the total solar spectrum. Relative increases in specific extinction and asymmetry factor with increasing relative humidity became larger at longer wavelengths. Significant variation in single-scattering albedo was found only in the longest near-IR band. This is also the band with the lowest albedo. A similar treatment was done for aerosols from biomass burning. In this case, size distributions were taken as having two carbonaceous size modes and a larger dust mode. The two carbonaceous modes were considered to be humidity dependent. Equilibrium size distributions and compositions were calculated for 15 relative humidities and five black carbon fractions. Mie calculations and Chandrasekhar averages of optical properties were done for each of the resulting 75 cases. Finally, fits were made for each of 12 spectral bands as functions of relative humidity and black carbon fraction.
Download or read book Optical Properties of Aerosol Emitted from Indoor Biomass Burning Cookstoves written by Samuel Arthur Whidden and published by . This book was released on 2023 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Optical Properties of Biomass Burning Aerosols Measured During FLAME 4 written by Rudra Prasad Pokhrel and published by . This book was released on 2015 with total page 78 pages. Available in PDF, EPUB and Kindle. Book excerpt: Optical properties of biomass burning aerosol at three different wavelengths (405, 532, and 660 nm) have been measured during the Fourth Fire Lab at Missoula Experiment (FLAME-4), which took place at the Fire Science Laboratory in Missoula, Montana, in October and November, 2012. During the experiment, absorption and extinction coefficients of aerosol emissions from biomass burning were measured. A photo-acoustic absorption spectrometer (PAS) measured the absorption coefficient of dry and denuded aerosol while a cavity ring-down spectrometer (CRDS) measured the extinction coefficient of dry and denuded aerosol. During the experiment, a wide range of fuels that represent significant sources of biomass emissions from different parts of world were burned. Fuels included trees, grasses, shrubs and peat. Fuels were burned in two different ways namely stack burns which allowed for measurements during different phases of the burn (flaming vs. smoldering) and room burns which allowed for detailed measurements of well mixed smoke from all phases of the fire. Single scattering albedo (SSA) and absorption angstrom exponent (AAE) values for the biomass burning aerosols have been calculated are now represented. Eight fuels were combusted during 20 individual stack burns and 12 fuels were analyzed during 21 room burns. Parameterizations of SSA and AAE as functions of modified combustion efficiency (MCE) and a proxy for the ratio of black carbon to organic carbon mass (BC:OA proxy) have been developed. The BC:OA proxy is found to shown better correlation to both SSA and AAE than does MCE. Combined of the stack and room burn results (41 individual burns and 12 different fuels) show that the BC:OA proxy can explain 94% of the variability in SSA and 70 % of the variability in AAE while MCE can only explain 40 % and 54 % of the variability in SSA and AAE, respectively.
Download or read book A Plan for a Research Program on Aerosol Radiative Forcing and Climate Change written by Panel on Aerosol Radiative Forcing and Climate Change and published by National Academies Press. This book was released on 1996-05-01 with total page 180 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book recommends the initiation of an "integrated" research program to study the role of aerosols in the predicted global climate change. Current understanding suggest that, even now, aerosols, primarily from anthropogenic sources, may be reducing the rate of warming caused by greenhouse gas emissions. In addition to specific research recommendations, this book forcefully argues for two kinds of research program integration: integration of the individual laboratory, field, and theoretical research activities and an integrated management structure that involves all of the concerned federal agencies.
Download or read book Multiphase Environmental Chemistry in the Atmosphere written by Sherri W. Hunt and published by ACS Symposium. This book was released on 2019 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book highlights new cross-disciplinary advances in aerosol chemistry that involve more than one phase, for example, unique chemical processes occurring on gas-solid and liquid-solid interfaces.
Download or read book Aerosol Remote Sensing written by Jacqueline Lenoble and published by Springer Science & Business Media. This book was released on 2013-02-11 with total page 423 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book gives a much needed explanation of the basic physical principles of radiative transfer and remote sensing, and presents all the instruments and retrieval algorithms in a homogenous manner. The editors provide, for the first time, an easy path from theory to practical algorithms in one easily accessible volume, making the connection between theoretical radiative transfer and individual practical solutions to retrieve aerosol information from remote sensing, and providing the specifics and intercomparison of all current and historical retrieval methods.
Download or read book Radiative Forcing of Climate Change written by National Research Council and published by National Academies Press. This book was released on 2005-03-25 with total page 222 pages. Available in PDF, EPUB and Kindle. Book excerpt: Changes in climate are driven by natural and human-induced perturbations of the Earth's energy balance. These climate drivers or "forcings" include variations in greenhouse gases, aerosols, land use, and the amount of energy Earth receives from the Sun. Although climate throughout Earth's history has varied from "snowball" conditions with global ice cover to "hothouse" conditions when glaciers all but disappeared, the climate over the past 10,000 years has been remarkably stable and favorable to human civilization. Increasing evidence points to a large human impact on global climate over the past century. The report reviews current knowledge of climate forcings and recommends critical research needed to improve understanding. Whereas emphasis to date has been on how these climate forcings affect global mean temperature, the report finds that regional variation and climate impacts other than temperature deserve increased attention.
Download or read book An Introduction to Atmospheric Radiation written by K. N. Liou and published by Academic Press. This book was released on 2002-04-29 with total page 599 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fundamentals of radiation for atmospheric applications -- Solar radiation at the top of the atmosphere -- Absorption and scattering of solar radiation in the atmosphere -- Thermal infrared radiation transfer in the atmosphere -- Light scattering by atmospheric particulates -- Principles of radiative transfer in planetary atmospheres -- Application of radiative transfer principles to remote sensing -- Radiation and climate.
Download or read book Carbonaceous Aerosol written by András Gelencsér and published by Springer Science & Business Media. This book was released on 2007-09-28 with total page 357 pages. Available in PDF, EPUB and Kindle. Book excerpt: The concept of carbonaceous aerosol has only recently emerged from atmospheric pollution studies; even standard nomenclature and terminology are still unsettled. This monograph is the first to offer comprehensive coverage of the nature and atmospheric role of carbonaceous aerosol particles. Atmospheric chemists, physicists, meteorologists, and modellers will find this a thought-inspiring and sometimes provocative overview of all global phenomena affected by or related to carbonaceous aerosol.
Download or read book Cavity Ring down Spectroscopy and the Retrieval of Aerosol Optical Properties from Biomass Burning During Flame2 written by Laura E. Mack and published by . This book was released on 2008 with total page 294 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Journal of Geophysical Research written by and published by . This book was released on 2004 with total page 534 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Biomass Burning Aerosols from African Wildfires written by Huihui Wu and published by . This book was released on 2022 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
