A more plausible reason for the “slowdown” of emissions

In their 2013 report “Trends in global CO2 emissions”, the PBL (Environmental Assessment Agency of the Netherlands) stated that CO2 emissions started to slow down. It was repeated four time in that page and a couple time in their interactive presentation. They came to this startling conclusion because of the last year trend of 1.1%, compared tot the average of the last decade, which was 2.9 °C and the reason for this slowdown was according to them partly caused by the growth of renewable energy. Also that got repeated several times.

It only takes looking at those ten last years to realize the answer will be a bit different. But let’s first start with how they represented it in their presentation:

If the difference between the years is so important, let’s calculate the differences between the years of the last decade in that graph (source of the data):

Year Emission
(in billion tonnes
(in %)
Corrected for leap year
(in %)
2002 26.066
2003 27.187 4.3 4.3
2004 28.552 5.0 4.7
2005 29.346 2.8 2.8
2006 30.345 3.4 3.4
2007 34.410 3.5 3.5
2008 31.962 1.8 1.5
2009 31.754 -1.2 -1.2
2010 32.992 4.5 4.5
2011 33.986 3.0 3.0
2012 34.453 1.4 1.1

This is the graph with the difference over that period:

Global emissions 2003-2012

Global emissions 2003-2012

This is not exactly a nice gradual slowdown year per year, it is more like a rollercoaster ride. Sure, the difference started high in 2003 and became even higher the next year, but in 2010 it came almost even higher. There also was a deep dip somewhat past the middle. The reason for this dip is obvious: the economic crisis.

When talking about the economic crisis, I have seen this graph before. Just look at the annual growth rates of the Gross World Product (GWP). Incorporated into the emission graph we get this:

Global emissions vs GDP 2003-2012

Global emissions vs GDP 2003-2012

This is not really hard to understand. More economic activity, more emissions. Less economic activity, less emissions. If this is not already part of the emission estimation, then it would be a real good contestant.

But in the world of PBL it is the growth of renewable energy sources that did the trick. Yeah, right.


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