?The Growth Rate in Chinese Emissions Has Been Incredible?
13 Jul, 2007 04:46 pm
Gregg Marland is an expert scientist on climate change, and he discusses the the findings by the Neatherlands Environmental Assessment Agency that show China has overtaken the United States in CO2 emissions.
Has this increase occurred sooner than expected?
Actually the numbers that came out of the Netherlands suggest that the Chinese emissions exceeded the US in 2006. According to my own calculations itís a toss up. There is always uncertainty in those kinds of numbers. I would say that the US was higher than China in 2006, but the crossover will most certainly occur in 2007. The growth rate in the Chinese emissions has been incredible. I donít think that anyone five years ago would have envisioned the crossover occurring this soon or even three years ago.
How are emissions tracked at the present time, and how accurate are these measurements?
Basically one takes the national consumption of fossil fuels Ė coal, oil, and natural gas- and you estimate the amount of carbon that is in each of these fuels, and as the fuel is burned the carbon is released as carbon dioxide. Ultimately you rely on statistics on energy use, and it is quite straightforward because carbon dioxide is released when you burn fossil fuels.
The problem is measuring how much energy is used. In the United States, for example, the statistics are probably pretty good, by about plus or minus 5 or 6%. In China the statistics are not nearly as strong, and the margin of error is quite a bit larger. The uncertainty could be 20% or so according to the Chinese statistics. I don't know if we care about which is larger -they are both very large numbers- but there is uncertainty if you want to argue about which is larger.
Interview by: Christopher Le Coq
Gregg Marland is a researcher in the Carbon-Climate Simulation Science Group at the Oak Ridge National Laboratory in Tennessee in the United States and a senior research scholar at the International Institute for Applied Systems Analysis in Laxenburg, Austria.