Development and Applications of Far Infrared Radiometry in Cold Atmospheres

寒冷大气中远红外辐射测量技术的发展与应用

• 批准号: RGPIN-2019-07256
• 负责人: Blanchet, JeanPierre
• 金额: $ 3.13万
• 依托单位: Université du Québec à Montréal
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2021
• 资助国家: 加拿大
• 起止时间: 2021-01-01 至 2022-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=739383
• 关键词: Development; Applications; Far; Infrared; Radiometry

The general aim of my research and for this proposal is to investigate the indirect effects of anthropogenic emission in the form of aerosols and precursor gases on the atmospheric water cycle at high latitudes. Central to this study is the observation of optically Thin Ice Clouds (TIC) and light precipitation (diamond dust), accounting for nearly 50% of the annual precipitation in the Arctic. Yet many of the occurrence of TIC are misreported as clear sky, since a ground observer sees stars during the polar night. Still, frequent light precipitations are reported as "trace", without a quantitative evaluation. As a result, TIC processes are still poorly represented in atmospheric models, leading to forecasting errors. It is now recognized that man-made aerosols can alter cloud and precipitation. The originality of my research is to fill an existing gap in cloud and light precipitation observation at high latitudes using a highly innovative method in the far infrared (FIR). These clouds, sensitive to aerosols via ice nucleation, can significantly modulate the amount of FIR (8-50µm) radiation escaping the Earth and affecting temperatures in the upper to mid troposphere and at the surface. Since FIR signature of clouds is very sensitive to their properties (crystals size and shape) and optical depth, these quantities can also be retrieved from ground-based and satellite observations. In this discovery program, theoretical calculations and measurements are used to show how the atmospheric far IR will provide valuable information for weather forecasting, data assimilation and climate simulations, about its water vapour content, the microphysical characteristics of ice clouds and common light precipitation. In this context, I am leading the "Thin Ice Clouds in the Far InfraRed Experiment" (TICFIRE) as a forthcoming satellite mission at the Canadian Space Agency (CSA). Endorsed by the Year of Polar Prediction program (YOPP, 2017-22), a World Meteorological Organisation initiative, in collaboration with the Canadian Space Agency (CSA) and Environment Canada (ECCC), with other universities and the industry (INO, LR Tech, Honeywell), I am leading new measurements in the mid and far IR range to advance our knowledge of TIC Polar clouds. This fall (2018), we have deployed the new Far IR Radiometer (FIRR-2), base on an innovative Canadian technology. The FIRR is a prototype for the future TICFIRE satellite and for a new ground-based instrument aimed to improve monitoring and weather prediction in Polar Regions. Under YOPP program, I am conducting innovative experiments and extended data analysis leading to operational applications of the FIRR and to study TIC microphysics and radiation interaction. Central to these measurements is the ability to evaluate accurately the size of ice crystals, here, my recent results have shown that for cold polar clouds and cirrus, the FIRR can outperform and complement other technologies.

我的研究和本提案的总体目标是调查高纬度地区气溶胶和前体气体形式的人为排放对大气水循环的间接影响。这项研究的核心是观测光学薄冰云（TIC）和轻降水（钻石尘），占北极年降水量的近50%。然而，许多TIC的发生被错误地报告为晴朗的天空，因为地面观察者在极夜看到星星。尽管如此，频繁的轻降水被报告为“微量”，没有定量评估。因此，TIC过程在大气模型中的代表性仍然很差，导致预测误差。现在人们认识到，人造气溶胶可以改变云和降水。我的研究的独创性是填补现有的空白云和光降水观测在高纬度地区使用一个高度创新的方法在远红外（FIR）。这些云通过冰成核对气溶胶敏感，可以显著调节逃离地球的FIR（8-50µm）辐射量，并影响对流层中上部和表面的温度。由于云的远红外特征对云的性质（晶体的大小和形状）和光学深度非常敏感，因此也可以从地面和卫星观测中检索这些量。在这一发现方案中，理论计算和测量被用来显示大气远红外将如何为天气预报、数据同化和气候模拟提供关于其水蒸气含量、冰云微物理特征和常见轻降水的宝贵信息。在这方面，我正在领导加拿大航天局（加空局）即将进行的一项卫星使命-“远红外实验中的薄冰云”。在世界气象组织极地预测年计划（YOPP，2017-22）的支持下，与加拿大航天局（CSA）和加拿大环境部（ECCC）合作，与其他大学和行业（INO，LR Tech，霍尼韦尔）合作，我正在领导中远红外范围的新测量，以提高我们对TIC极地云的认识。今年秋天（2018年），我们部署了基于加拿大创新技术的新型远红外辐射计（FIRR-2）。FIRR是未来TICFIRE卫星的原型，也是一种新的地面仪器，旨在改善极地地区的监测和天气预报。根据YOPP计划，我正在进行创新实验和扩展数据分析，导致FIRR的业务应用，并研究TIC微观物理和辐射相互作用。这些测量的核心是准确评估冰晶大小的能力，在这里，我最近的结果表明，对于寒冷的极地云和卷云，FIRR可以优于和补充其他技术。