Methods and apparatus for measuring gas flux

US11460480B2 · kind B2 · utility

Assignee

• LI-COR, Inc. · US

Inventors

• George Burba · Lincoln, US
• Dayle K. McDermitt · Lincoln, US
• Xiaomao Lin · Lincoln, US
• Liukang Xu · Lincoln, US
• Dave Johnson · Vancouver, CA

Key dates

• Filing date: Aug 8, 2018
• Grant date: Oct 4, 2022
• Expiry date: Mar 18, 2041

Classification

• Technology area (CPC G): Physics
• CPC primary: G01W1/10
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

Systems and methods for measuring turbulent gas flux using high-speed vertical wind speed measurements (e.g., on the order of 5-10 Hz or more frequently) and low-speed gas content measurements (e.g., on the order of 5 Hz or less frequently), without the need for the sophisticated and expensive high-speed hardware to separate gas samples (e.g., into accumulation bags) according to updrafts and downdrafts. A time series of high-speed vertical wind speed data is used as a guide to distinguish between updrafts and downdrafts. When vertical wind speed is upward (updraft), the low-speed gas content is recorded into a data structure in one location, or marked with one flag. When vertical wind speed is downward (downdraft), the low-speed gas content is recorded into a different location, or marked with a different flag. Eddy Accumulation or Relaxed Eddy Accumulation computations can be performed using the stored gas content data to determine gas flux.