Radiative Transfer in Absorbing Aerosols and Snow Grains: Theory and Experiment

该项目是首席研究员对冰的辐射传输特性的长期研究的发展，并将注意力转向光的吸收和散射，因为黑碳（烟灰）和各种大小，形状和成分的尘埃颗粒污染了冰粒和雪粒。 实验室实验，数值模拟和理论方法相结合，将适用于这项调查，这将部分取决于几何光子跟踪方法，以更好地确定在可见光和红外波长的污染冰的辐射散射特性。 将进行系统的分析，以提高物理理解和洞察力的计算效率的方法，推导雪量（即能量反射率）的辐射传输模型表示单一和多个雪层，包括雪颗粒大小和形状的各种组合，黑碳/尘雪混合物，以及太阳辐射入射角的实际变化。这项工作的智力价值涉及到提供一个坚实的理论和模型-减少与大气和积雪条件变化相关的气候系统强迫的不确定性的基础。 更广泛的影响将来自于通过改进模型预测和相关的敏感地区水资源管理的改进，包括但不限于冰川山脉和极地地区，以及通过研究生和本科生教育，提高预测积雪快速变化的能力。

This project is an evolution of the Principal Investigator's longstanding research on radiative transfer properties of ice, and turns attention to the absorption and scattering of light as altered by contamination of ice particles and snow grains by black carbon (soot) and dust particles of various sizes, shapes and composition. A combination of laboratory experimentation, numerical simulations and theoretical approaches will be applied to this investigation, which will in-part hinge on a geometric photon tracing method to better determine radiative scattering properties of contaminated ice at both visible and infrared wavelengths. A systematic analysis will be undertaken to improve physical understanding and insight into computationally efficient methodologies deriving snow albedo (i.e. energy reflectance) from a radiative transfer model representing both single and multiple snow layers that include a variety of combinations of snow grain size and shape, black carbon/dust-snow mixtures, and realistic variations of the incident angle of solar radiation.The intellectual merit of this work relates to providing a firm theoretical and model-based foundation for reducing uncertainties in climate system forcing associated with changing atmospheric and snowpack conditions. Broader impacts will derive from improved ability to anticipate rapid changes in snowcover via improved model predictions and associated improvements in water resource management in sensitive areas, including but not limited to glaciated mountains and polar regions, as well as through student education at both graduate and undergraduate levels.