Estimating methane (CH₄) emission rates using quantitative CH₄ retrievals from the Next Generation Airborne Visible/Infrared Imaging Spectrometer (AVIRIS-NG) requires the use of wind speeds. Model wind speeds have limited temporal and spatial resolution, meteorological station wind data are of variable quality and are often not available near observed plumes, and the use of ultrasonic anemometers co-located with methane sources is impractical for AVIRIS-NG flight campaigns with daily coverage of thousands of square kilometers. Given these limitations, this study focused on the use of the Twin Otter Doppler Wind Lidar (TODWL) to measure near surface winds and provide coincident measurements to CH₄ plumes observed with AVIRIS-NG. In a controlled release experiment, TODWL observed wind speed and direction agreed well with ultrasonic anemometer measurements and CH₄ emission rates derived from TODWL observations were more accurate than those using the ultrasonic anemometer or model winds during periods of stable winds. During periods exhibiting rapid shifts in wind speed and direction, estimating emission rates proved more challenging irrespective of the use of model, ultrasonic anemometer, or TODWL wind data. Overall, TODWL was able to provide reasonably accurate wind measurements and emission rate estimates despite the variable wind conditions and excessive flight level turbulence which impacted near surface measurement density. TODWL observed winds were also used to constrain CH₄ emissions at a refinery, landfill, wastewater facility, and dairy digester. At these sites, TODWL wind measurements agreed well with wind observations from nearby meteorological stations, and when combined with quantitative CH₄ plume imagery, yielded emission rate estimates that were similar to those obtained using model winds. This study demonstrates the utility of combining TODWL and AVIRIS-NG CH₄ measurements and emphasizes the potential benefits of integrating both instruments on a single aircraft for future deployments.

使用来自下一代机载可见光/红外成像光谱仪 (AVIRIS-NG) 的定量 CH ₄反演估算甲烷 (CH ₄ ) 排放率需要使用风速。模型风速的时间和空间分辨率有限，气象站风数据质量参差不齐，通常无法在观测到的羽流附近获得，并且使用超声波风速计与甲烷源共同定位对于每日覆盖的 AVIRIS-NG 飞行活动是不切实际的数千平方公里。鉴于这些限制，本研究侧重于使用双水母多普勒测风激光雷达 (TODWL) 来测量近地表风并为 CH ₄提供重合测量用 AVIRIS-NG 观察到的羽状物。在控释实验中，TODWL 观测到的风速和风向与超声波风速计测量结果非常吻合，并且从 TODWL 观测得出的CH ₄排放率比在稳定风期间使用超声波风速计或模型风的排放率更准确。在风速和风向快速变化的时期，无论使用模型、超声波风速计或 TODWL 风数据，估计排放率都更具挑战性。总体而言，尽管风况多变，飞行高度湍流影响近地表测量密度，但 TODWL 仍能够提供相当准确的风测量和排放率估计。TODWL 观测到的风也被用来限制 CH ₄炼油厂、垃圾填埋场、废水设施和乳品消化池的排放。在这些站点，TODWL 风测量与附近气象站的风观测结果非常吻合，并且当与定量 CH ₄羽流图像结合时，产生的排放率估计值与使用模型风获得的估计值相似。这项研究展示了结合 TODWL 和 AVIRIS-NG CH ₄测量的效用，并强调了将这两种仪器集成在一架飞机上以供未来部署的潜在好处。