Lagrangian Balloon for Atmospheric Research

该补助金支持设计，建造和测试用于大气探测的气球，该气球具有主动浮力控制，使其能够随风移动。 通过忠实地跟踪空气运动，它提供了一个所谓的拉格朗日参考系，用于测量温度，压力，湿度，臭氧和其他痕量气体。 需要这些测量来观测气团在高层大气中经历光化学和云物理过程时的历史。 例如，缺乏极地平流层云形成的重要细节，因为这些云形成的空气团的温度历史没有足够的准确性。 此外，热带地区空气团运动的不确定性掩盖了水蒸气进入平流层的机制，使预测臭氧层将如何应对气候变化的努力难以进行。 拉格朗日气球是“南瓜”设计，直径9米，配备了内部伺服机构，以改变其体积，以响应垂直空气运动相对于气球。 浮力不断调整，以尽量减少垂直空气运动，使气球跟踪空气的相对速度保持尽可能接近零。 气球可以携带用于测量相对于气球的垂直空气速度的仪器的轻型有效载荷，热力学变量，以及用于与地面通信的卫星调制解调器。 来自马萨诸塞州大学和史密斯学院皮卡工程项目的学生将参与该项目。

This grant supports the design, construction, and testing of a balloon for atmospheric sounding that has an active buoyancy control to enable it to move with the wind. By faithfully tracking the air motions, it provides a so-called Lagrangian frame of reference for measurements of temperature, pressure, humidity, ozone, and other trace gases. These measurements are needed to observe the histories of air parcels as they undergo photochemical and cloud physical processes in the high atmosphere. For example, important details in the formation of polar stratospheric clouds are lacking because the temperature histories of the air parcels in which these clouds form are not known with sufficient accuracy. Moreover, uncertainties in air parcel motion in the tropics mask the mechanism by which water vapor enters the stratosphere, confounding attempts to predict how the ozone layer will respond to climate change. The Lagrangian balloon is of "pumpkin" design, nine meters in diameter, equipped with an interior servomechanism to change its volume in response to vertical air motions relative to the balloon. The buoyancy is continually adjusted to minimize the vertical air motion, so that the balloon tracks the air with a relative velocity held as near to zero as possible. The balloon can carry a light payload of instruments for measuring the vertical air velocity relative to the balloon, thermodynamic variables, and a satellite modem for communicating with the ground. Students from the University of Massachusetts and the Picker Engineering Program at Smith College will participate in the project.