Friday, 15 April 2016

COP21 Pledges for greenhouse gas emissions

Guest Post by Tom Quirk 

A supplement by Dr Tom Quirk to the previous post by Des Moore -

 on the pledges made at last December’s meeting in Paris.

Originally posted by Joanne Nova at

189 countries submitted pledges to the COP21 meeting in Paris at the end of 2015. These have been sorted and summarised in a very useful website Carbon Brief[1]. The following analysis is based on the top 12 countries for greenhouse gas emissions. This covers 72% of the world total but ignores forest and peat fires. The pledges cover broadly defined greenhouse gas emissions. For instance Brazil has land use emissions that are estimated at 4 times the sum of their other contributions.

The total greenhouse gas emissions for 2012 were 10.85 Gt C in CO2-equivalent while total CO2 emissions were estimated to be 9.68 Gt C in CO2. (Source Carbon Dioxide Information Analysis Center CDIAC[2])

The pledges have been standardized to be from 2012 to 2030 as countries have chosen various starting points to indicate their plans. The most important and most uncertain pledge is the target for China. The 75% increase indicated below is a “best estimate”.

For greenhouse gas emissions the pledges would see an increase from 7.83 Gt C to 9.59 Gt C for the 72% fraction analysed. This is a 23% increase. It is clear that China is both the major contributor to the increase and the source of the greatest uncertainty.

USA performance for CO2

For the USA the CDIAC record of CO2 emissions shows the conversion from using coal to natural gas in power stations has driven the decline in CO2 emissions. An example of an innovation by reduced cost not subsidy. The indicated targets for USA emissions are labelled intention with a 28% reduction of total emissions by 2025. The extension to 2030 gives a reduction of 25% from 2012 to 2030.

China performance for CO2

For China the CDIAC record shows the importance of coal use in power stations. This will drive emission increases.

The key pledge is a 60% cut to the 2005 CO2 emission intensity (CO2 emissions per unit of GDP).

The table below shows the relationship of GDP to CO2 emissions. The estimates used to calculate the 2030 emissions are based on 5% annual GDP growth and a pledged CO2 intensity of 0.96 CO2 in tonnes C-equiv per $10,000 of GDP.

Population 2012 (million)
GDP per capita 2013 (World Bank)
CO2 emissions per capita in  tonnes C  2012 (CDIAC)
CO2 Intensity:
CO2 per GDP in tonnes C per $10,000 GDP

 Australian performance for greenhouse gas emissions  
The Australian performance is reported by two agencies, first CDIAC giving CO2 and second greenhouse gas emissions in CO2 equivalent C from the Federal Government Department of the Environment[3].
It is worth noting that the present annual increases in China’s annual emissions are equal to the annual emissions from Australia.

Australian emissions black total are mostly due to coal (red squares)

For Australia the use of black and brown coal provides the fuel for power generation. The plateau in energy emissions which is seen in both records may be due to increasing electricity prices limiting demand as well as the closing of mineral processing plants such as aluminium smelters. The decline in greenhouse gas emissions starting in 2006 appears to be due to changes in the land use contribution. Land contributions are not well measured and subject to accounting rule changes.

The present government has avoided a direct carbon tax that would impact commercial activity by introducing a Direct Action plan for plant and soil sequestration of CO2. 

Further the changes in land use accounting rules will help the Direct Action plan but the time needed for this plan to have an impact is uncertain. So the 31% reduction in emissions from 2012 to 2030 remains problematic.


A glaring omission in the COP21 meeting was consideration of forest and peat fires which may produce as much as half of all fossil fuels burned. (See also “Where have those fossil fuel emissions gone?“). [They forget phytoplankton too, says Jo Nova.]  

The fires are treated as “acts of God” since He or She is not anthropogenic (an interesting philosophical question). Thus these emissions are no longer included in the inventory of contributions. However the annual forest and peat fires CO2 emissions are estimated to be equal to 50% of present total annual fossil fuel CO2 emissions[4].

Only one country, North Korea has decarbonised itself at great cost to its people. There, per capita emissions have dropped from 3 tonnes C in CO2 in 1997 to less than 1 tonne C in CO2. The best illustration of this is the NASA image of the Korean peninsula at night.

Night image of the Korean Peninsula in 2014 shows that North Korea is almost completely
dark compared to neighboring South Korea and China (source NASA).

Finally the best summary for COP21 is to be found in the Bolivian submission where capitalism is “a system of death”, carbon markets are rejected and a call for a world carbon budget between countries, with 89% allocated to the developing world.

However what is clear from the pledges is that China and India will become the largest emitters of greenhouse gases with rises in the standard of living in both countries. Why should they curtail their growth?

So how can this COP21 “construct” work?

[4] David M. J. S. Bowman, Jennifer K. Balch, Paulo Artaxo, William J. Bond, Jean M. Carlson, Mark A. Cochrane, Carla M. D’Antonio, Ruth S. DeFries, John C. Doyle, Sandy P. Harrison, Fay H. Johnston, Jon E. Keeley, Meg A. Krawchuk, Christian A. Kull, J. Brad Marston, Max A. Moritz, I. Colin Prentice, Christopher I. Roos, Andrew C. Scott, Thomas W. Swetnam, Guido R. van der Werf, Stephen J. Pyne: Fire in the Earth System, Science, Vol 324 24 April 2009 481

Tom Quirk trained as a nuclear physicist at the University of Melbourne where he took courses in meteorology. He has been a Fellow of three Oxford Colleges

No comments:

Post a comment

All serious comments published after moderation.
Comments should be polite, and respect all views.
No bad language. Spam never makes it!