Most of us that follow climate news are aware of the CO2 measurements that come from the Mauna Loa Observatory in Hawaii where two different measuring stations are continuously monitoring carbon dioxide levels.
The two scientific institutions at the Mauna Loa Observatory (MLO) on the Big Island of Hawaii are the National Atmospheric and Oceanic Administration (NOAA) and Scripps Institution of Oceanography (SIO). On the CO2 Earth website, the readings from the two stations are given on a daily basis.
Another very important scientific station measures CO2 levels in the Southern Hemisphere. It is located at Cape Grim in western Tasmania, Australia. In this region of the world, CO2 levels have usually stayed below 400 ppm because the atmosphere has been fairly stable. But once the CO2 levels reach the “point of no return” or above 400 ppm, there won’t be any going back. Right now, the average CO2 levels at Cape Grim are above 398.710 ppm.
Cape Grim is one of the three major Baseline Air Pollution Stations (BAPS) in the World Meteorological Organization-Global Atmosphere Watch (WMO-GAW) network. Baseline stations must meet a specific set of criteria for measuring greenhouse and ozone depleting gases and aerosols in clean air environments to be BAPS.
Why we should worry about CO2 levels
Scientists are warning us that once the global CO2 levels reach above 400 ppm, there is the very good chance they will never drop below that point, even if we do manage to curb greenhouse gas emissions. That is why it’s so important and necessary that we do something now to curb the use of fossil fuels.
In 2013, the BAPS at Mauna Loa recorded CO2 levels at 400 ppm for the first time since monitoring began. While there has been the occasional dip below the threshold a few times due to seasonal cycles, the monthly average of CO2 levels has not dropped below 400 ppm since 2015. As a matter of fact, the monthly average for April this year is 407.57 ppm at Mauna Loa.
At Cape Grim on May 6, 2016, the CO2 level was recorded at 399.9 ppm. This news, according to scientists from the Commonwealth Scientific and Industrial Research Organisation (CSIRO), which runs the Cape Grim station, is very surprising and disconcerting, as it should be.
“We wouldn’t have expected to reach the 400 ppm mark so early,” David Etheridge, CSIRO atmospheric scientist, told the Guardian. “With El Nino, the ocean essentially caps off its ability to take up the heat so the concentrations are growing fast as warmer land areas release carbon.”
“So we would have otherwise expected it to happen later in the year,” he added. “No matter what the world’s emissions are now, we can decrease growth but we can’t decrease the concentration. Even if we stopped emitting now, we’re committed to a lot of warming.”
And that is what is so worrying. Once CO2 levels remain above the 400 ppm mark, there will be no going back, and there is no one to blame but us, humans. This situation has led to the belief that rising greenhouse gas levels are driving global warming.
We have seen the horrible effects of climate change more this year than in any previous years. The extraordinarily high ocean surface temperatures have bleached coral reefs around the world, devastating the great barrier Reef in Australia. And land temperatures, they are shocking, too, and the future does not bode well for any relief.
