Cornell Flux Chamber¶

  • Project overview
  • Mechanical design
  • Electrical design
  • Calibration and deployment instructions
  • Resources and literature

Project overview¶

Methane (CH4) emissions are increasing globally. Yet, partitioning different sources of methane emissions remains challenging due to the limited spatial and temporal scale of field measurements. Improving ground measurements of CH4 flux will allow us to identify and quantify how different policy and management actions can reduce emissions. In order to increase ground measurements of CH4 flux, we need affordable, rugged, and portable sensors that can be deployed for days to weeks at a time. This webpage documents the design, construction, and field testing of 10 prototype chambers to measure CH4 and carbon dioxide (CO2) flux from a variety of environments (e.g., manure, wetlands, lakes, agricultural fields). The development of these affordable, portable, rugged, and easy to use chambers will expand ground CH4 flux measurements world-wide, ultimately providing much-needed science to inform carbon policy.

This webpage is dynamic, and will be updated as the project progresses.

Mechanical design¶

  • Design considerations $\longrightarrow$ Agreed upon first variation shown on this page.
  • Chamber design $\longrightarrow$ Current mechanical prototype.

Electrical design¶

Sensor considerations

  • Sensor trade study
  • Overview of sensor options, for discussion with colleagues

As we develop libraries for communicating with the various sensors and components that compose our floating flux chamber, those libraries, schematic, layout, etc. will be documented on webpages linked below. All project code lives in this git repository.

  • Methane sensor $\longrightarrow$ Selected Figaro NGM 2511-E13.
  • CO2 sensor (+temp, +humidity) $\longrightarrow$ Selected Sensiron SCD30.
  • Switches
  • SD card
  • Real time clock
  • Stepper motors

The integration of electronic components and testing results.

  • Flux chamber $\longrightarrow$ The main body of code to run the integrated motor and data logging system.
  • Printed circuit board $\longrightarrow$ The integrated electronic component.
  • Terminal interface $\longrightarrow$ A debugging interface to test motor and logging settings.
  • Testing $\longrightarrow$ Results and demonstration video.

Calibration and deployment instructions¶

To be populated.

Resources and literature¶

  • The proposal for this project, which describes our objectives
  • Self-Made Equipment for Automatic Methane Diffusion and Ebullition Measurements From Aquatic Environments
  • Technical note: Facilitating the use of low-cost methane (CH4) sensors in flux chambers – calibration, data processing, and an open-source make-it-yourself logger
  • Methane and carbon dioxide fluxes at high spatiotemporal resolution from a small temperate lake
  • Jonas Stage git repo
  • Building J-Sensors
  • Calibrating J-Sensors