CO2 concentration in the atmosphere – May and April over 400 ppm; since June in decline, the year on year comparisons show an up-rise trend

Climate change is becoming the most important challenge for humanity in the near future. Understanding the driving factors of global warming is a starting (and key) point in order to address this challenge. One of these factors is the measure of CO2 concentration in the atmosphere. According to the record of CO2 and temperature preserved in ice sheets in Antarctica and Greenland, there is a clear correlation between CO2 concentration in the atmosphere and air temperature (the higher the concentration, the higher air temperature will be).

 

This is why we are going to present (at www.lteconomy.it/en) every two or three months the weekly figures on CO2 concentration at the Mauna Loa centre (the site chosen by Charles D. Keeling, the scientist who started the studies on the proportion of carbon dioxide in the atmosphere).

 

On May 9th 2013, CO2 concentration at the Mauna Loa Observatory reached (for the first time since the beginning of recording) 400 parts per million (ppm) (for more details on the meaning of this measure, see the following  article and the interview with Pieter Tans, Head of the Maunha Loa Observatory). It is a high value, considering that it was 280 ppm in the pre-industrial era and a concentration of 500 ppm is considered by some scientists as an irreversible point, by which Earth will reach a new hotter equilibrium. Since then, weekly observations have gradually decreased, reaching 393.21 ppm in the 5th week of September 2013. Then, the index has gradually rebounded and in March and April 2014, it has exceeded the 400 ppm again; in the second week of May CO2 concentration in the atmosphere reached a new historical peak at 401.79 ppm. It was over 400 ppm for all the weeks of June; than falling to 399.83 in the first week of July.

Besides, it is important to notice that year-on-year comparisons of the 1st week in each month of 2013 and 2014, in terms of ppm, show always a positive difference, proving a growing trend in CO2 concentration at the Mauna Loa center. The year-on-year difference ranges from 1.26 (1^st week of February), to 3.58 (1^st week of April). So, supposing that this trend is destined to continue, if we consider an annual increase of 2-3 ppm in CO2 concentration, this measure will reach the tremendous 500 ppm by just a little bit more than 30-40 years.

 

Tab. Co2 concentration at Mauna Loa center since August 2013, year-on-year comparison

Source: LTEconomy, elaboration on ESRL-NOAA

 

Source: LTEconomy, elaboration on ESRL-NOAA

LTEconomy, April 2014

 

From

ESRL-NOAA, April 2014
http://www.esrl.noaa.gov/gmd/ccgg/trends/weekly.html