A longer time base depicts the ever increasing trend of atmospheric concentration experienced since 1980.
Source: NOAA ESRL: ftp://aftp.cmdl.noaa.gov/products/trends/co2/co2_mm_gl.txt
June 2016's global average of 403.57 ppm is 3.78 ppm above June 2015, a record year to year increase, surpassing September 1998's 3.58 ppm increase, and July, 2013's increase of 3.48 ppm.
It is this ongoing increase of CO2 rates of concentration that creates sobering concern for our future.
For example, in 1998, the months of August to October recorded increases of more than 3 ppm over prior year. June to August, 2013, also were months experiencing more than a 3 ppm jump over the prior year.
However, in 2016 every month - January to June - has had a year to year increase of over 3 ppm, culminating in June, 2016 with the new record increase of 3.78 ppm, something never witnessed in the ESRL data.
|Year||Month||CO2 ppm||1 Yr Chng|
Source: NOAA ESRL
However, while year to year data will show significant fluctuation, generally around ENSO changes, what is more troubling are the persistent accelerating rates of change over time.
Five Year CO2 Increase - A New Accelerating Record
The June, 2016 CO2 increase over June 2011, was 12.63 ppm, the highest 5 year change recorded, To highlight the increasing rate of change, we had never experienced a five year increase of more than 10 ppm before September, 2002, when we observed a 10.23 ppm jump over 1997. From May, 2005 till April, 2008 - only 4 months had an increase less than 10 ppm. After that, the five year increase rate bounced above and below 10 ppm till March, 2013.
Since March, 2013, for 39 months, we have not experienced a increase of less than 10 ppm in any month compared to five years before. What is worse is that we observed our first months above 11 ppm in July to August 2014, over the same months in 2009.
But that has been eclipsed by the trend beginning in December, 2015, when each month since - seven months in a row - have been above a five year increase of 11 ppm. That has been surpassed as well, for March to June 2016, have all had a five year increase above 12 ppm, with June setting a new record of a 12.63 ppm increase over June, 2011.
|Year||Month||CO2 ppm||5 Yr Chng|
Source: NOAA ESRL
Ten year CO2 Increase - Another New Accelerating Record
The June, 2016 CO2 increase from June, 2006 was also the highest recorded - 22.02 ppm. Our first month of over a 20 ppm increase in a 10 year period was September, 2007, when it hit, 20.17 ppm. Four of seven months from then till March, 2008 were above a 10 year increase of 20 ppm.
From October, 2010 till May, 2012 all but three months were above a 20 ppm increase over the same month 10 years before.
Since October, 2012, for 43 months, no month has witnessed an increase under 20 ppm.
The first time we observed a month with over a 21 ppm increase was December, 2015, and amazingly, 6 months later, we have gone over a 22 ppm increase.
|Year||Month||CO2 ppm||10 Yr Chng|
Source: NOAA ESRL
The following graph illustrates the entire set of trends.
Source NOAA ESRL: ftp://aftp.cmdl.noaa.gov/products/trends/co2/co2_mm_gl.txt
Our recent jump is often described as a "product" of the recent El Nino, but more specifically, it is a result of increasing drought, forest fires, and more menacing - the decreasing capacity of the oceans to absorb carbon as they experience heating. These are anticipated to continue and increase as the more global warming occurs.
While these increase rates may drop in the coming months, as the effects of El Nino fade, we may be witnessing new baselines laid for future acceleration. Given that since 2003, we have experienced six monthly year to year peak increases well over 2 ppm, and since 2006, ever increasing peaks in that monthly CO2 change, it seems likely, that in the next 5 years, we will experience a month with a year on year CO2 increase of 4 ppm.