POPC4OM: Understanding population controls on cloud-circulation coupling based on observationally-constrained modeling

信风区的积云场在地球气候系统中起着重要作用，持续覆盖着亚热带信风区的大部分地区。多年来，气候模式中涉及积云参数化的系统性偏差被发现通过云气候反馈对未来气候预测造成了重大的不确定性，但人们对云气候反馈的了解仍然很少。这反映了我们对积云场如何与大尺度环境和环流耦合的普遍缺乏了解。最近和即将在大西洋贸易风地区开展的实地活动旨在更深入地了解这一问题。2013年和2016年进行了两次NARVAL活动（下一代飞机遥感验证研究），而即将到来的EUREC 4A实地活动（阐明云-环流耦合在ClimAte中的作用）计划于2020年初进行。高空和远程研究飞机（HALO）通过有效和频繁地对偏远地区进行采样，在这些实地活动中发挥了关键作用。该项目旨在将NARVAL-II和EUREC 4A期间收集的积云及其环境的联合收割机HALO观测与高分辨率大涡模拟和概念积云总体建模相结合。第一个研究目标是创建大规模的强迫数据集，完全基于HALO下投式探空仪测量。第二个目标是评估这些过程模型对独立的HALO和中分辨率成像光谱仪云的测量，反映散装的属性和云人口的变化。第三个也是最后一个目标是使用这种协同作用的建模和测量，以获得更多的洞察力积云人口动态的控制在信风地区的云环流耦合。

Cumulus cloud fields in the Trade wind regions play an important role in Earth's climate system, persistently covering substantial areas of the subtropical Tradewind regions. Over the years systematic biases involving cumulus parameterizations in climate models have been found to cause significant uncertainty in future climate predictions, through cloud-climate feedbacks that are still poorly understood. This reflects our prevailing lack of understanding of how cumulus cloud fields are coupled to the larger-scale environment and circulation. Recent and upcoming field campaigns in the Atlantic Tradewind regions are designed to give more insight into this problem. Two NARVAL campaigns (Next-Generation Aircraft Remote Sensing for Validation Studies) took place in 2013 and 2016, while the upcoming EUREC4A field campaign (ElUcidating the Role of Clouds-Circulation Coupling in ClimAte) is scheduled to take place in early 2020. The High Altitude and LOng-range research aircraft (HALO) plays a key role in these field campaigns, by sampling remote areas effectively and frequently. This project aims to combine HALO observations of cumulus clouds and their environment as collected during NARVAL-II and EUREC4A with high-resolution Large-Eddy Simulations and conceptual cumulus cloud population modeling. The first research objective is to create large-scale forcing datasets that are exclusively based on HALO dropsonde measurements. The second objective is to evaluate these process models against independent HALO and MODIS cloud measurements, reflecting both bulk properties and cloud population variability. The third and final objective is to use this synergy of modeling and measurements to gain more insight into the control of cumulus population dynamics on the cloud-circulation coupling in the Tradewind regions.