Atmospheric Aerosols Their Optical Properties And Effects

Aerosol models have been developed for the lower atmosphere. These models are representative of conditions found in rural, urban, and maritime air masses. The changes in the aerosol properties with variations in the relative humidity are discussed. To describe the aerosol optical properties in the extreme of 100 percent relative humidity, several fog models are presented. For each model the coefficients for extinction, scattering, and absorption, the angular scattering distribution, and other optical parameters have been computed for wavelengths between 0.2 and 40 microns. These aerosol models are presented together with a review of their experimental basis. The optical properties of these models are discussed and some comparisons of the model with experimental measurements are presented.

This book provides the first comprehensive analysis of how aerosols form in the atmosphere through in situ processes as well as via transport from the surface (dust storms, seas spray, biogenic emissions, forest fires etc.). Such an analysis has been followed by the consideration of both observation data (various field observational experiments) and numerical modeling results to assess climate impacts of aerosols bearing in mind that these impacts are the most significant uncertainty in studying natural and anthropogenic causes of climate change.

The challenges faced by the atmospheric research community today are vast, complex, and multi-faceted. The book Urban Atmospheric Aerosols: Sources, Analysis, and Effects highlights important aspects concerning the chemical and optical properties, size distribution, sources, and potential health effects of fine urban air particles (PM2.5). The physical and chemical characterization of PM2.5, its source assignment, and the assessment of the magnitude and distribution of its emissions are crucial for establishing effective fine air particle regulations and assessing the associated risks to human health. This book brings together eight papers covering the main topics of the field and will be of interest to researchers who are interested in air quality in outdoor and indoor environments, air particle toxicity, and atmospheric chemistry, as well as global climate modelers.

This textbook aims to be a one stop shop for those interested in aerosols and their impact on the climate system. It starts with some fundamentals on atmospheric aerosols, atmospheric radiation and cloud physics, then goes into techniques used for in-situ and remote sensing measurements of aerosols, data assimilation, and discusses aerosol-radiation interactions, aerosol-cloud interactions and the multiple impacts of aerosols on the climate system. The book aims to engage those interested in aerosols and their impacts on the climate system: graduate and PhD students, but also post-doctorate fellows who are new to the field or would like to broaden their knowledge. The book includes exercises at the end of most chapters. Atmospheric aerosols are small (microscopic) particles in suspension in the atmosphere, which play multiple roles in the climate system. They interact with the energy budget through scattering and absorption of solar and terrestrial radiation. They also serve as cloud condensation and ice nuclei with impacts on the formation, evolution and properties of clouds. Finally aerosols also interact with some biogeochemical cycles. Anthropogenic emissions of aerosols are responsible for a cooling effect that has masked part of the warming due to the increased greenhouse effect since pre-industrial time. Natural aerosols also respond to climate changes as shown by observations of past climates and modelling of the future climate.

The book describes the morphological, physical and chemical properties of aerosols from various natural and anthropogenic sources to help the reader better understand the direct role of aerosol particles in scattering and absorbing short- and long-wave radiation.

The book is divided into two sections. The first section presents characterization of atmospheric aerosols and their impact on regional climate from East Asia to the Pacific. Ground-based, air-born, and satellite data were collected and analyzed. Detailed information about measurement techniques and atmospheric conditions were provided as well. In the second section, authors provide detailed information about the organic and inorganic constituents of atmospheric aerosols. They discuss the chemical and physical processes, temporal and spatial distribution, emissions, formation, and transportation of aerosol particles. In addition, new measurement techniques are introduced. This book hopes to serve as a useful resource to resolve some of the issues associated with the complex nature of the interaction between atmospheric aerosols and climatology.

This new text offers experienced students a comprehensive review of available techniques for the remote sensing of aerosols. These small particles influence both atmospheric visibility and the thermodynamics of the atmosphere. They are also of great importance in any consideration of climate change problems. Aerosols may also be responsible for the loss of harvests, human health problems and ecological disasters. Thus, this detailed study of aerosol properties on a global scale could not be more timely.