Source: NOAA ESRL: http://www.esrl.noaa.gov/gmd/ccgg/trends/weekly.html
Today's Mauna Loa CO2 weekly average figure is astounding. This time of year, atmospheric CO2 concentrations are declining as usual in a normal Northern Hemisphere summer. In a post-El Nino environment, one would expect CO2 increases to slow even more compared to prior years. However CO2 levels in Hawaii for the last seven days is 5.04 ppm higher than the same week last year.
This is the first weekly average ever reported above 5 ppm since records began in 1974.
For example the week ending June 12, 2016 was 4.78 ppm higher that the corresponding one in 2015. Similarly the week ending September 6, 1998 was 4.67 ppm than 1997.
In fact, only 16 weekly averages have had greater than 4.00 ppm increase over the prior year since 1974. Three occurred in 1998, Over half (nine) have been reported in 2016.
The table is all weeks with higher than 4 ppm increase over prior year, by one year change.
Year Mon Day CO2 ppm Pr Yr ppm 1 Yr Chng
There does seem to be a change in the trend of weekly change from 1975-2016. As noted above, most weekly 1 year change increases above 4.00 ppm occur after 2010, and most in the warming period or El Nino through 2016. This graph shows those changes.
What we are witnessing has no parallel in prior year increases, and while one week does not make a trend, the concern of ever increasing CO2 concentrations in our atmosphere at an accelerating rate is something humanity wants to definitely avoid.