Aerosol Particle Effects on Warm and Cold Cloud Formation

气溶胶颗粒对暖云和冷云形成的影响

• 批准号: 0436196
• 负责人: Paul DeMott
• 金额: $ 57.8万
• 依托单位: Colorado State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-12-01 至 2007-11-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0436196&HistoricalAwards=false
• 关键词: Aerosol; Particle; Effects; Warm; Cold

All cloud droplets and many ice crystals form on suspended particles in the atmosphere. This laboratory investigation will study key aspects of these "nucleation" processes. The study emphasizes the nucleating properties of organic material (including pure organic species and the organic material in soils) and mineral dust because they have not been studied extensively before and there is an increasing body of evidence that points to their importance in the atmosphere. Three different kinds of laboratory measurement will be made: water uptake on particles in subsaturated conditions, activity of particles as cloud-condensation nuclei (CCN), and ice nucleation of pure solution droplets or caused by undissolved particles. Samples of soil from regions that are significant sources of desert dust will be collected and re-suspended for these analyses. A key hypothesis to be tested is that the characteristics of dust from different arid regions of the world have similar characteristics and so might be represented by common parameterizations. Other objectives of this project will be to examine particles of known mixed composition and to develop and test parametric representations of the results. The expected result is new characterization of the nucleating properties of some key constituents of the atmospheric aerosol and the development of new ways of representing those characteristics that can be used in weather and climate models of those processes. This has potential to influence future forecasts of precipitation and representations of the important radiative properties of clouds in climate models.

所有云滴和许多冰晶在大气中的悬浮颗粒上形成。这项实验室研究将研究这些“成核”过程的关键方面。该研究强调了有机材料的成核特性（包括纯有机物物种和土壤中的有机材料）和矿物灰尘，因为在之前没有对它们进行广泛的研究，并且有越来越多的证据表明它们在大气中的重要性。将进行三种不同类型的实验室测量：在粉粒条件下颗粒上的水吸收，颗粒作为云构核（CCN）的活性以及纯溶液液滴的冰核或由未溶解的颗粒引起的。将收集来自重要的沙漠灰尘来源的土壤样品，并重新悬浮以进行这些分析。要测试的关键假设是，来自世界各个干旱地区的灰尘的特征具有相似的特征，因此可以用共同的参数化表示。该项目的其他目标将是检查已知混合成分的粒子，并开发和测试结果的参数表示。预期的结果是大气气溶胶某些关键成分的成核特性的新表征以及代表这些过程中可用于这些过程的这些特征的新方法的发展。这可能会影响气候模型中云的重要辐射特性的未来预测和对云的重要辐射特性的表示。