The key US National Oceanic and Atmospheric Administration (NOAA) site where CO2 concentrations in the air are monitored, at Mauna Loa, Hawaii. Unlike CO2 emissions, these CO2 concentrations can be readily measured directly, so Edward Ionides, José Tapia Granados, and Óscar Carpintero used them to study their link with global GDP. Credit NOAA
Researchers have confirmed a relationship that is making climate change tough to fight: economic growth and atmospheric CO2 concentrations have been tightly linked for the past 50 years. That’s what the University of Michigan‘s Edward Ionides and co-workers found by looking at levels of the greenhouse gas and gross domestic product (GDP), an important measure of countries’ financial performance, at a worldwide level. “GDP growth is like a proxy for CO2 concentration growth,” Edward told Simple Climate. “Under business-as-usual conditions, these two quantities are measuring essentially the same thing. This highlights a problem with using GDP as a measure of progress.”
Until now, much research on the link between CO2 and economic growth has looked at figures for each country. Some think using each country’s CO2 emissions separately “should be more informative”, Edward said. But there are problems with recording emissions accurately, plus goods or services used in one country often result in CO2 emissions in another. So, with Michigan colleague José Tapia Granados, and Óscar Carpintero from the University of Valladolid, Spain, Ionides went to the worldwide level for “a new and simpler perspective”.
As well as the total of all countries’ GDP, they used precisely measured atmospheric CO2 levels, rather than the more uncertain emission figures. “In addition, concentration of CO2, rather than the level of emissions, is the variable directly determining the global climate,” Óscar said. “Change in the atmospheric concentration is the result of emissions – mainly from burning fossil fuels, since natural emissions from volcanoes are estimated as a tiny fraction of man-made emissions – minus removals by natural sinks.”
Atmospheric CO2 (monthly average) as measured in air samples collected at Mauna Loa, Hawaii from Feburary 1958 to Februrary 2012. Units are parts per million by volume. Estimated preindustrial concentrations, at levels between 200 and 300 ppm, would be far out of the graph. The graph is often known as the Keeling curve. Credit: University of Michigan
