CO2 and climate change

The CO2 concentration in the atmosphere, the Earth’s average temperature and climate change are closely linked.

If carbon dioxide concentration increases, the atmosphere’s temperature increases, the ice melts faster, sea level rises and rainfall regimes changes dramatically.

To prevent radical climate change, scientists have determined the maximum CO2 concentration in the atmosphere at 450ppm, the value by which global warming should stay within 2°C. A larger increase could not be supported by the planet without profound alteration of the current balance.

Concentration of CO2 in the atmosphere

315
1958
349
1987
364
1997
383
2007
396
2013
399
2014
Parti per milione (ppm)

We do not know exactly what will happen, if the current balance was totally upset, but there are many movies that can give the most dramatic ideas … Anyway seems inevitable that the melting glaciers will increase sea level, erasing a good chunk of the current coast where a large part of world population lives…

Already today it is evident the retreat of the ice on the Alps, in the Arctic and also on the Himalayas, but the real critical points are the immense glaciers of Antarctica and Greenland, which, liquefying, would release in the ocean an impressive amount of water.

But what does it mean to keep temperature increase below 2°C? What have been the CO2 concentration in the atmosphere?

Before the industrial revolution, CO2 concentration was estimated at 280ppm, while he was already 315ppm in 1958 (first year with accurate measurements), 349ppm in 1987, 364ppm in 1997, in 2007 383ppm, 396ppm to 399ppm in 2013 and in 2014, with an average annual increase in the last 10 years around 2ppm in constant acceleration, leading to the treshold of 450ppm in less than 30 years. Slowing CO2 concentration growth will not be sufficient, while it will be necessary to reduce the emission till a new equilibrium where CO2 released will be equal to the amount the Earth can absorb. Therefore, even though thirty years may sound a lot of time, we have to act now, first slowing the growth, then stabilizing it, and, eventually, reducing it to the correct value… you can think we’re in the highway at 120mph speeding, while the limit is 90mph … We need to start braking before our license is withdrawn ….