Thanks to a European research project of literally global proportions, scientists have been able to determine that much of the carbon monoxide residing in the atmosphere above Australia is produced by wildfires in South America. Australia’s wildfires are notorious; however, scientists suspected other factors were at play above the biomass-poor regions of central Australia. Biomass incineration, i.e. wildfires, is the largest cause of carbon monoxide in the lower reaches of the atmosphere. Researchers using the Dutch-German satellite instrument SCIAMACHY aboard Europe’s environmental satellite Envisat were able to determine that local fires couldn’t be responsible for the CO levels observed by Dr Annemieke Gloudemans of the Netherlands Institute for Space Research (SRON), and her colleagues.
The SCIAMACHY sensors used by Dr Gloudemans and her team are sensitive enough to measure the short-wave infrared radiation required to detect carbon monoxide levels throughout the atmosphere. ‘This allows us to map the sources of carbon monoxide and see where they are blown to’, says Gloudemans. ‘We have done it for all of the continents in the southern hemisphere: South America, Australia, and Southern Africa, with surprising results.’
|Despite their intensity, Australian wildfires aren’t the sole culprit behind elevated CO levels.
Studying the results gathered from the high precision sensors, Dr Gloudemans and colleagues from Utrecht University, the Vrije Universiteit Amsterdam and the Netherlands Meteorological Institute (KNMI) originally posited that the high concentrations of CO in central regions were coming from fires further north. ‘Initially we assumed that the wildfires in North Australia were responsible for this. Yet when we took a closer look at the transport of carbon monoxide, we had to conclude that the majority originated from fires in South America. Even for the carbon monoxide above the fires in North Australia, one-third originated from South America.’
Dangerously high levels of carbon monoxide and other gases released into the atmosphere can have serious repercussions for mankind and the environment, and satellite sensors are of critical importance in keeping tabs on the fluctuations of gas levels in the atmosphere. Dr Gloudemans presented her research recently at an Envisat-conference in Montreux, Switzerland celebrating the fifth anniversary of its launch.
Dr Ilse Aben, head of atmospheric research at SRON, noted how vital such research is to our understanding of the environment and the fact that Envisat’s decommission date is rapidly approaching. ‘The only way to accurately follow the emission and transport of carbon monoxide is to use satellites with sensors that are sensitive enough for short-wave infrared radiation. That also applies for methane, after carbon dioxide the most important anthropogenic greenhouse gas,’ Dr Aben explained. ‘Envisat will be decommissioned in about 2010. Unless we work quickly on a successor, we will no longer be able to track the emission and spread of these substances.’
Envisat, built by the European Space Agency and launched in March of 2002, is one of the largest European satellites and carries numerous updated versions of instruments central to previous missions.