Historic record of atmospheric gas reveals positive impact of human intervention

Global intervention in the late 20th century was successful in stabilizing the concentration of carbon monoxide in the atmosphere, research has found.

In a study published on Thursday, a team of scientists led by Australia's Commonwealth Scientific and Industrial Research Organisation (CSIRO) and the French National Centre for Scientific Research (CNRS) measured air to assemble the first complete record of carbon monoxide concentration in the southern hemisphere.

Carbon monoxide (CO) is a poisonous gas that impacts climate change by reacting with the gas hydroxyl, which naturally removes other greenhouse gases causing global warming from the atmosphere, reducing its abundance.

By measuring air in polar ice, scientists were able to measure CO concentration in the atmosphere over the last three millennia.

David Etheridge, a CSIRO atmospheric scientist, said in a media release that the record shows atmospheric CO started climbing at the time of the industrial revolution and accelerated through most of the 1900s.

"The good news is that levels of the trace gas are now stable or even trending down and have been since the late 1980s - coinciding with the introduction of catalytic converters in cars," he said.

An emission control device that converts toxic exhaust gasses, including CO, into less toxic pollutants, catalytic converters have been mandatory in all new cars in Australia since 1986 and in the European Union since 1993.

"The stabilisation of carbon monoxide concentrations since the 1980s is a fantastic example of the role that science and technology can play in helping us understand a problem and help address it," Etheridge said.

He said that the stabilization of CO has allowed hydroxyl to more efficiently reduce the level of greenhouse gasses such as methane in the atmosphere.