On 18 April 2017, atmospheric carbon dioxide (CO2) levels were measured at 410.28 parts per million (ppm). This marks the first time in human history that atmospheric CO2 levels were measured at above 410 ppm.
The numbers don’t denote thresholds, but they are important for scientists and the general public to mark the dangerously rising levels of CO2 in the atmosphere.
“It’s pretty depressing that it’s only a couple of years since the 400 ppm milestone was toppled,” Gavin Foster, a paleoclimate researcher at the University of Southampton told Climate Central last month. “These milestones are just numbers, but they give us an opportunity to pause and take stock and act as useful yard sticks for comparisons to the geological record.”
The Scripps Institution of Oceanography recorded the milestone at Mauna Loa Observatory in Hawaii. It was determined using a Keeling Curve, which is a graph which plots the ongoing change in concentration of carbon dioxide in Earth’s atmosphere.
2016 marked the first time in several million years that the atmospheric concentration of CO2 passed 400 ppm. Due to unbridled global warming and a disproportionate response from our end, scientists predicted that the CO2 concentration will only increase further in 2017. (Report here.)
Noting the historic 2016 numbers, Ralph Keeling, director of the Scripps Institution of Oceanography’s CO2 Programme, said, “We’re in a new era … And it’s going fast. We’re going to touch up against 410 pretty soon.”
Surely enough, we touched 410 last month, and are en route to reach more sobering heights. The optimum CO2 level to sustain earth as we know lies below 350 ppm. We crossed that threshold way back in 1990, and the condition has only worsened since then. It stood at 280 ppm when record keeping began in 1958. In 2013, it passed 400 ppm. Today, it is at 410 ppm.
What does high CO2 concentration do?
410 ppm means that in an air sample with moisture taken out, out of one million molecules, 410 were CO2.
CO2 traps the Sun’s heat in the Earth’s atmosphere – a phenomenon known as the greenhouse effect. More carbon dioxide means more heat is trapped, causing global warming and climate change.
Although not the worst possible CO2 level, 410 ppm is a tipping point. Like all climate tipping points, there isn’t an immediate catastrophe. It’s less a cliff, and more a slope that gets steeper as you descend.
More carbon dioxide also means polar ice will melt faster, raising sea levels sooner. Higher carbon dioxide concentrations also cause oceans to become acidic, harming marine life.
Global action against climate change – the historic importance of the Paris Agreement
“The rate of increase will go down when emissions decrease,” Pieter Tans, a scientist at the National Oceanic and Atmospheric Administration, said. “But carbon dioxide will still be going up, albeit more slowly. Only when emissions are cut in half will atmospheric carbon dioxide level off initially.”
Furthermore, Columbia University climatologist James Hansen had said, “If humanity wishes to preserve a planet similar to that on which civilisation developed and to which life on Earth is adapted … CO2 will need to be reduced … to at most 350 ppm.”
Climate action has been late in its maturity, with the first truly global effort to combat climate change, the Paris Agreement, being finalised only in 2015. However, the world has finally begun taking climate change seriously.
China, for example, has introduced a cap on coal and will peak coal emission by 2030.
Germany will ban combustion engines by 2030.
In the US, high-profile advocates for the environment have funded a 20-year clean energy fund to the tune of US$1 billion.
India has aimed to achieve 40% cumulative electric power capacity from non-fossil fuel sources by 2030.
Britain recently set a record the world was happy to see: it had its first coal-free power day in 135 years.
The Logical Indian take
Before the Industrial Revolution, the earth had 280 ppm of CO2. It has climbed sharply in the last few decades. CO2 levels have risen 24% since 1958. Environmentalists want to go back to 280 ppm. Many others want it to fall to 350 ppm.
460 ppm can potentially cause global temperatures to rise by 3 degrees celsius. Currently, we are 0.9 degrees celsius above the accepted level, and the recently signed Paris Agreement on climate change wants it to remain below 1.5 degrees celsius.
“History is calling,”former UN Secretary-General Ban Ki-moon had said to leaders in Paris on 1 December 2015. He reminded them of the abject lack of time we were facing and the abundant responsibility they were carrying. It seems that we have beat the historical odds and are now better equipped than ever before to face the challenges of the future.
Climate change is probably the biggest global problem of our time. Implementing the Paris Agreement will be the first concrete step in reversing the drastic consequences of climate change which have endangered our very existence. With CO2 levels continuing to rise, the need for an effective global effort against climate change is the most urgent need of the hour.