Remote sensing of Arctic aerosols: analysis of intensive parameters

气溶胶是一种大气颗粒，其大小从一微米的一小部分(1/1000000米)到几十微米不等。它们的浓度可能会有很大(广泛)的变化，它们的大小、形状和化学成分也会有很大(强烈)的变化。地面太阳光度测量是测量平均气溶胶效应的主要技术；一种是全天跟踪太阳，测量仪器和太阳之间的气溶胶造成的衰减。气溶胶(特别是细微的、亚微米的气溶胶)在污染事件期间对健康有重大影响。它们对辐射和云层特性的影响是重要的气候变化因素。北极地区的气候变化比南部地区更为严重，气溶胶在促成这些变化方面发挥了重要作用。因此，重要的是要充分了解气溶胶，特别是北极气溶胶的物理性质。 我的长期目标是根据可测量的光学变化更好地了解气溶胶行为。例如，在掌握影响测量的基本环境和仪器物理之前，无法理解某些特定的气溶胶光学厚度光谱形状、天空辐射角度变化的变化或气溶胶高度属性的激光雷达(脉冲激光)测量的变化的意义。这一目标有利地伴随着涉及使用光学数据评估气溶胶动力学模型的项目；我们的经验是，模型评估过程不可避免地加强了一个人对该模型声称要模拟的气溶胶现象和测量本身的物理理解。 研究建议的短期目标是更好地理解二阶(密集)气溶胶光学参数的可测量物理。这具体意味着使用光谱技术来提取精细和粗略模式的有效半径值，以及提取单次散射反照率(对气溶胶吸收敏感)。

Aerosols are atmospheric particles whose size ranges from a small fraction of a micrometer (1/ 1000000 of a meter) to tens of micrometers. They can exhibit large (extensive) variations in concentration and significant (intensive) variations in their size, shape and chemical composition. Ground-based sunphotometry is the predominant technique for measuring average aerosol effects; one tracks the sun all day and measures the attenuation caused by the aerosols between the instrument and the sun. Aerosols (notably fine, sub-micron aerosols) have significant health impacts during pollution events. Their effect on radiation as well as on cloud properties represent important climate change factors. Climatic changes in the Arctic are more severe than in southern regions and aerosols play a major role in contributing to these changes. It is accordingly important that the physical properties of aerosols and Arctic aerosols in particular be well understood. My long term objective is to better understand aerosol behavior in terms of measurable optical variations. The significance, for example, of some specific aerosol optical depth (AOD) spectral shape, a change in the angular variation of sky radiance, or variations in lidar (pulsed laser) measurements of aerosol altitude properties, cannot be understood until one has a grasp of the essential environmental and instrumental physics influencing the measurement. This objective is advantageously accompanied by projects involving the evaluation of aerosol dynamics models using optical data; our experience has been that the process of model evaluation inevitably enhances one's physical understanding of both the aerosol phenomena which the model purports to simulate and the measurements themselves. The short term objective of the research proposal is to better understand the measurable physics of second order (intensive) aerosol optical parameters. This specifically means the employment of spectral techniques to extract fine and coarse mode effective radius values and the extraction of single scattering albedo (sensitive to aerosol absorption).