Measurements of Total Water on the Gulfstream-V for Deep Convective Clouds and Chemistry (DC3)

上对流层/下平流层(UTLS)区域水汽、臭氧、气溶胶和卷云的综合影响强烈地调制了地球气候系统的辐射强迫。这一区域的组成不仅受到化学过程的影响，而且还受到动力过程的影响，如跨对流层顶交换和源自地球表面的对流输送。将于2012年5月至6月进行的深对流云和化学(DC3)实地活动将支持研究大陆中纬度雷暴系统对UTLS组成和化学在三个区域(即，科罗拉多州东北部、俄克拉何马州和得克萨斯州西部以及阿拉巴马州北部)，具有不同的背景化学和特征风暴行为。该奖项将支持对现有的基于可调谐半导体激光的仪器--科罗拉多大学闭路激光湿度计--的改装，以便在DC3期间在NSF/NCAR GV研究飞机上测量总水(可从中得出冷凝液体和冰水含量)。将与恩布里-里德尔航空大学的一名顾问合作，设计和建造一个专门针对GV上选定采样位置的新入口，以实现对大范围云粒(10-400微米)的准确采样。这项研究的智力优势在于提供了对中纬度对流云系上游高空间分辨率的总水量的精确和准确的测量，这反过来将使研究人员能够描述切变驱动雷暴和气质型雷暴的不同输送特性，以及它们在云生命周期中演变的微物理特性。以及在活跃对流停止后的12-48小时期间，不同地区和不同时间的砧板辐射环境是如何不同的。更广泛的影响将包括研究生培训和公众宣传，但最终将延伸到更好地了解对大气臭氧的控制以及与气候评估和政策制定的相关联系。

Combined influences of water vapor, ozone, aerosols and cirrus clouds in the upper-troposphere/lower-stratosphere (UTLS) region serve to strongly modulate radiative forcing of the earth's climate system. The composition of this region is affected not only by chemical processes, but also by dynamical ones such as cross-tropopause exchange and convective transports originating near the earth's surface. The Deep Convective Clouds and Chemistry (DC3) field campaign, to be conducted May-June 2012, will support study of the contrasting impacts of continental midlatitude thunderstorm systems on UTLS composition and chemistry within three regions (viz. northeastern Colorado, western Oklahoma and Texas, and northern Alabama) characterized by differing background chemistry and characteristic storm behavior. This award will support adaptation of an existing tunable diode laser-based instrument, the University of Colorado closed-path laser hygrometer, to make measurements of total water (from which condensed liquid and ice water contents may be derived) aboard the NSF/NCAR GV research aircraft during DC3. A new inlet specific to the selected sampling location aboard the GV will be designed and built in collaboration with a consultant from Embry-Riddle Aeronautical University to enable accurate sampling of a wide range of cloud particle sizes (10-400 micrometers).The intellectual merit of this research rests on provision of precise and accurate measurements of total water at high spatial resolution within the upper reaches of midlatitude convective cloud systems, which will in-turn allow investigators to describe differing transport properties of shear-driven vs. airmass-type thunderstorms, their attendant evolving microphysical properties over cloud lifecycles, and how anvil radiative environments differ from region to region and with time during the interval 12-48 hours after cessation of active convection. Broader impacts will include graduate student training and public outreach, but will ultimately extend to improved understanding of controls on atmospheric ozone and associated links to climate assessment and policy formulation.