Collaborative Research: Parameterization of Gas Flux at High Wind Speed

氧气和氮气的海气交换速率将在高到极端风速(20-60m/S)下测量。根据这些数据，可以对气体交换过程和通量速率的参数进行物理理解。定制的跟随水的拉格朗日花车将在2008年至2009年期间被空中部署到飓风中。将使用两种不同的商用氧传感器和定制的气体总张力传感器的组合，从O2和N2的混合层预算以及垂直速度和气体浓度的涡旋协方差来测量通量。浮标还将测量温度和盐度、表面波谱、表面波破碎率和气泡特性。额外的EM-APEX浮标剖面将提供模拟天然气收支混合部分所需的温度、盐度和速度的深度-时间分布。风力和压力数据将由运行中的飞机遥感和滴落探测仪数据提供。通量测量技术将在2006年和2007年SOLAS-DOGEE计划的两次北大西洋巡航期间与其他方法进行比较。建模和数据分析将侧重于理解气泡介导的气体传输的物理学，并将利用这一理解来制定高风速下气体传输速率的新参数。高风速下气体交换率参数的不确定性导致直接计算的全球海洋二氧化碳净吸收的不确定度高达70%。这项工作的目的是通过改进参数化来减少这些不确定性。该项目开发的气体传感器将投入商业使用。它们将专门设计用于自动平台，如花车、滑翔机、水面漂浮器和自动水下机器人。目前招收的一名研究生将通过完成博士论文获得资助。本科生将在暑假期间参加罗德岛大学和华盛顿大学的课程。

The rate of air-sea exchange of O2 and N2 will be measured at high to extreme wind speeds (20-60 m/s). A physical understanding of the gas exchange processes and parameterizations of the flux rates will be developed from this data. Custom-built water-following Lagrangian floats will be air-deployed into hurricanes during 2008 and 2009. Fluxes will be measured from the mixed layer budgets of O2 and N2 and from the eddy-covariance of vertical velocity and gas concentration using a combination of two different commercial oxygen sensors and custom-built total gas tension sensors. The floats will also measure temperature and salinity, surface wave spectra, surface wave breaking rates and bubble properties. Additional profiling EM-APEX floats will provide the depth-time profiles of temperature, salinity and velocity necessary to model the mixing component of the gas budgets. Wind and pressure data will be provided by operational aircraft remote sensing and drop sonde data. The flux measurement techniques will be compared with other methods during two North Atlantic cruises of the SOLAS-DOGEE program during 2006 and 2007. Modeling and data analysis will focus on understanding the physics of bubble-mediated gas transfer and will use this understanding to formulate new parameterizations of gas transfer rates at high wind speeds.Broader Impacts.Gas exchange across the air-sea interface is a key component of the global carbon budget. Uncertainties in the parameterizations for gas exchange rate at high wind speeds lead to uncertainties of up to 70% in the directly computed net global CO2 uptake by the ocean. This work aims to reduce these uncertainties by improving the parameterizations. The gas sensors developed by this project will be commercially available. They will be specifically designed for use on autonomous platforms such as floats, gliders, surface drifters and autonomous underwater vehicles. One currently enrolled graduate student will be supported through the completion of his Ph.D thesis. Undergraduates will participate during the summers at both the University of Rhode island and the University of Washington.