Scientists at the National Physical Laboratory (NPL) have produced a synthetic air reference standard which can be used to accurately measure levels of carbon dioxide and methane in the atmosphere. This will greatly help scientists contribute to our understanding of climate change.
A paper published in Analytical Chemistry describes how researchers at NPL have created a synthetic gas standard for the first time, which is comparable to the World Meteorological Organisation (WMO) scale and can be quickly produced in a laboratory and distributed, meeting growing demand.
The bulk of demand for gas standards comes from atmospheric monitoring stations around the world. The data collected from these is important to our understanding of climate change.
To reliably compare the concentration of carbon dioxide and methane in air at different locations, and over time, a primary standard to which all measurements relate is required. We must be able to relate the measurements to a trusted base unit, so we can reliably compare measurement between London and Beijing, or between 1990 and 2014.
The current primary standards for carbon dioxide and methane are a suite of cylinders of compressed air captured from Niwot Ridge in Colorado and held at the National Oceanic and Atmospheric Administration (NOAA).
They are used to create secondary standards, which are used to calibrate the instruments that measure greenhouse gasses around the world.
A new improved measurement technique - cavity ring-down spectroscopy (CRDS) - has resulted in a dramatic increase in the number of atmospheric measurements taken. As the requirement for data that is comparable to the WMO scale increases, there is a corresponding increase in the demand for comparable reference standards.
Supplying the demand for reference standards comparable to the WMO scale is becoming an issue. An infrastructure to disseminate reference standards
|Contact: Alex Cloney|
National Physical Laboratory