Remote sensing and analysis of 2nd order, Arctic-aerosol parameters

气溶胶通常被定义为大气颗粒，其尺寸范围从一微米的一小部分到几十微米。它们源自多种气溶胶排放过程：森林火灾、风吹沙漠、气体至颗粒转化、火山爆发和海浪过程是一些主要的天然气溶胶来源，而城市和工业过程导致的化石燃料燃烧是最重要的人为来源。气溶胶至少就其光学效应而言，可以大致分为双峰、细模和粗模分量（半径大约是亚微米和超微米）。在接下来的五年里，我们将继续研究双模态参数的特性，如精细模式和粗糙模式气溶胶光学厚度（基本上与气溶胶的柱浓度成比例的参数）以及作为气溶胶种类的函数的精细和粗糙模式有效半径（平均柱半径）。本DG应用背景下的拟议研究将侧重于从表面和柱状光学仪器中提取折射率信息（作为气溶胶散射特性的重要驱动因素的真实的部分和作为气溶胶吸收特性的主要驱动因素的复杂部分）的风险更高。这些活动将被细分为三个研究项目：（一）一个为期2年的博士后领导的研究检索的折射率的真实的和复杂的部分从表面光谱测量和光学性能推导出微物理和物种表面测量。(ii)一个光学检索分析，由一名博士生领导，对pdf项目的细模折射率结果的表面到柱的传播进行分析 (iii)由第二名博士生领导的并行粗模式分析（与第一名博士生密切合作）。北极的遥感研究在社会效益方面特别重要，因为众所周知，该地区会放大气候变化的影响（例如，如最近的IPCC报告所述）。气溶胶由于其直接（散射和吸收）效应和间接（气溶胶-云相互作用）效应，是气候变化动力学中最大的不确定性来源（同上）。更好地了解气溶胶光学物理参数，特别是密集参数，如平均尺寸和折射率，将有助于校准和改进北极气溶胶模型的气溶胶动力学包，从而导致辐射强迫和北极气候模型方面的重要后果。

Aerosols are commonly defined as atmospheric particles whose size ranges from a small fraction of a micrometer to tens of micrometers. They originate from a large variety of aerosol emission processes : forest fires, wind-blown deserts, gas to particle conversion, volcanic eruptions and ocean wave processes are some of the major natural aerosol sources while fossil fuel combustion due to urban and industrial processes is the most important anthropogenic source. Aerosols can, at least as far as their optical effects are concerned, be largely divided into bi-modal, fine and coarse mode components (roughly sub and super micrometer in radius).Over the next five years, we will continue to pursue research into the characterization of bi-modal parameters such as fine and coarse mode aerosol optical depth (a parameter which is basically proportional to the column concentration of aerosols) and fine and coarse mode effective radius (average columnar radius) as a function of aerosol species. The proposed research within the context of this DG application will be focused on the higher risk extraction of refractive index information (both the real part which is an important driver of aerosol scattering properties and complex parts which is the major driver of aerosol absorption properties) from both surface and columnar optical instruments. These activities are will be subdivided into three research projects : (i) a 2-year postdoc led study on the retrieval of real and complex parts of the refractive index from surface spectral measurements and optical properties deduced from microphysical and speciation surface measurements. (ii) an optical retrieval analysis, led by a PhD student, of surface to column propagation of the fine mode refractive index findings of the pdf project (iii) a parallel coarse mode analysis (in close collaboration with the first PhD student) led by a second PhD student.Remote sensing research in the Arctic is particularly relevant in a social benefit context since this region is known to magnify climate change effects (as described in the most recent IPCC report for example). Aerosols, by virtue of their direct (scattering and absorption) effects and indirect (aerosol cloud interaction) effects are the greatest source of uncertainty in climate change dynamics (ibid). A better understanding of aerosol opto-physical parameters, notably intensive parameters such as average size and refractive index will help to calibrate and improve the aerosol dynamics packages of Arctic-aerosol models and accordingly lead to important consequences in terms of radiative forcing and climate models of the Arctic.