Coordinated Airborne Studies in the Tropics (CAST)

全球鹰具有独特的研究能力，可以在对流层上层和平流层下层进行超长飞行，为推进大气科学提供了重要的新机遇。为了响应NERC/STFC/NASA的合作倡议，我们组建了一个经验丰富的英国团队，提议执行一项涵盖基础科学和技术发展的研究计划，通过与全球鹰合作，将从根本上提高我们未来的研究能力。热带对流层顶（TTL）是化学/气候相互作用的关键区域。在我们已经完成的工作的基础上，我们将与NASA的ATTREX项目合作，通过新的测量和分析来研究太平洋和东南亚的TTL。我们将讨论与大气成分、辐射和运输有关的基本问题。TTL控制水蒸气（一种至关重要的辐射气体）进入平流层的输送；我们将进一步了解亚可见卷云在水蒸气过程中的作用。TTL也是极短寿命卤素物种进入平流层的主要途径，这些物种在未来的平流层臭氧演变中具有很大的不确定性。我们将提高对这些气体的预算及其通过TTL的化学转化和输送的认识，包括对流输送到TTL的作用以及随后从TTL输送到平流层下层的路线。改善这些过程在全球化学/气候模式中的代表性是一个关键目标。为了研究这些过程，FAAM BAe-146将于2014年1月/ 2月部署在关岛。它将与“全球鹰”协调飞行，后者将在同一时期在西太平洋上空进行TTL测量。与ATTREX合作任务的所有阶段的详细参与将增强英国使用“全球鹰”进行未来研究的潜力，包括在任务规划和复杂实时数据分析方法方面的先进能力。利用一组互补的区域高分辨率模式、全球成分模式和全球卷云模式，将结合地面和气球对极短寿命卤素物种和臭氧的测量对飞机测量结果进行解释。我们将为有效载荷/任务-科学家界面开发和测试两种新仪器和新软件，它们非常适合“全球鹰”的能力。一种新的仪器将允许在TTL中量化亚微米和超微米大小的粒子的重要物理特性，从而提供有关云和辐射的新信息。利用对流层上层和平流层下层超长飞行的优势，研制新型短波红外光谱仪，遥感测量低层大气中的温室气体（CO2、CH4、H2O）和其他（CO）气体。这两种仪器都将在CAST进行飞行测试。除了解决这一呼吁的具体问题外，CAST还解决了技术主题的核心愿景：“让NERC社区内外的科学家、技术专家、计算机专家和工程师参与进来，认识到在许多情况下，只有通过发展新的伙伴关系，才能实现最具挑战性的技术创新”（http://www.nerc.ac.uk/research/themes/tap/documents/tap-technologies-2009.pdf）。CAST为NERC社区带来了机器学习方面的新技术专业知识，并加强了NERC科学家与赫特福德郡和天文技术中心技术小组之间的联系。

The unique research capability of the Global Hawk, with ultra-long flights possible in the upper troposphere and lower stratosphere, provides a major new opportunity to advance atmospheric science. In response to the NERC/STFC/NASA collaborative initiative, we have assembled an experienced UK team that proposes to execute a research programme covering fundamental science and technology development, which, by working with the Global Hawk, will radically enhance our future research capabilities.The Tropical Tropopause Layer (TTL) is a crucial region for chemistry/climate interactions. Building on work we have already done in this area , we will collaborate with NASA's ATTREX programme to study the TTL over the Pacific Ocean and South East Asia, with new measurements and analysis. We will address fundamental questions related to atmospheric composition, radiation and transport. The TTL controls the transport of water vapour, the crucial radiative gas, into the stratosphere; we will advance understanding of the role of sub-visible cirrus in water vapour processes. The TTL is also the main route by which very short-lived halogen species, which represent a large uncertainty in future stratospheric ozone evolution, enter the stratosphere. We will improve knowledge of the budgets of these gases and of their chemical transformation and transport through the TTL, including the role of convective transport into the TTL and the subsequent routes for transport from the TTL to the lower stratosphere. Improving representation of these processes in global chemistry/climate models is a key aim.In order to study these processes, The FAAM BAe-146 will be deployed in Guam in Jan/Feb 2014. It will fly coordinated flights with the Global Hawk which will make measurements in the same period in the TTL over the West Pacific. Detailed involvement in all phases of the collaborative missions with ATTREX will enhance the UK potential for future research using the Global Hawk, including advanced capability in mission planning and methodologies for complex, real-time data analysis. The aircraft measurements will be interpreted in conjunction with ground-based and balloon-based measurements of very short-lived halogen species and ozone, using a complementary group of regional high resolution models, global composition models and a global cirrus model.We will develop and test two new instruments and new software for the payload/mission-scientist interface, which are ideally suited for the capabilities of the Global Hawk. One new instrument will allow quantification in the TTL of the important physical properties of sub- and super-micron sized particles, allowing new information about clouds and radiation. We will develop a new short-wave IR spectrometer to measure greenhouse (CO2, CH4, and H2O) and other (CO) gases in the lower atmosphere by remote sensing, taking advantage of the very long flights in the upper troposphere and lower stratosphere. Both instruments will be flight-tested in CAST.As well as addressing the specifics of this call, CAST addresses the central vision of the Technology theme: "to engage scientists, technologists, computer specialists and engineers working both within the NERC community and outside it, identifying that in many cases it will only be through developing new partnerships that the most challenging innovations in technology can be enabled" (http://www.nerc.ac.uk/research/themes/tap/documents/tap-technologies-2009.pdf). CAST brings new technology expertise in machine learning into the NERC community and strengthens the links between NERC scientists and the technology groups at Hertfordshire and the Astronomy Technology Centre.