The objective of monitoring atmospheric greenhouse gas concentrations is to document rates of increase and to estimate the magnitude of sources and sinks from atmospheric concentration patterns.  This information will be important in defining policies aimed at lowering the human contribution to the greenhouse effect and climate change.  The largest gap in the greenhouse gas global monitoring system is the lack of regular measurements of the vertical profile of such gases over continental areas.  In order to make such measurements economically possible CCGG has developed an automated system for obtaining air samples from aircraft.


The aircraft sampling system consists of two packages, one containing batteries and compressors, and one containing 20 sampling flasks and a microcontroller.  The system connects to a clean air inlet, but requires no additional modification to the aircraft.  This makes system installation and configuration simple.

Aircraft Sampling Package

In the laboratory we analyze the air samples for CO2, CH4, N2O, CO, H2, SF6, and the isotopic ratios of CO2.  Results are used to construct vertical profiles and time series grouped by altitude.  These data are used in inverse models to "translate" the observed concentration patterns into estimates of regional carbon sources and sinks.

Veritcal Profile Plots

The system has been in use since 1992 in Northern Colorado aboard small aircraft.  It is now undergoing further engineering development to adapt it to a wider range of aircraft.  

Aircraft used for sampling, Carr, Colorado