Total US Greenhouse Gas Emissions In 2006 Down 1.5% From 2005; Transportation Sector Up 0.5%
28 November 2007
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| Greenhouse gas emissions in the US economy. Click to enlarge. |
Total US greenhouse gas (GHG) emissions were 7,075.6 million metric tons carbon dioxide equivalent (MMTCO2e) in 2006, a decrease of 1.5% from the 2005 level, according to Emissions of Greenhouse Gases in the United States 2006, a report by the Energy Information Administration (EIA).
Total greenhouse gas emissions from the transportation sector rose 0.5% from 2005 to 2006, reaching 2,010.3 MMTCO2e. Carbon dioxide emissions represented 93.75% of total transportation GHG in 2006 (1,884.7 MMTCO2).
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| Transportation sector emissions from gasoline and diesel fuel combustion generally parallel total vehicle miles traveled. Click to enlarge. |
Transportation sector carbon dioxide emissions in 2006 were 407.5 million metric tons higher than in 1990, an increase that represents 46.4% of the growth in unadjusted energy-related carbon dioxide emissions from all sectors over the period.
Since 1999, the transportation sector has led all US end-use sectors in emissions of carbon dioxide. Petroleum combustion is the largest source of carbon dioxide emissions in the transportation sector, as opposed to electricity-related emissions in the other end-use sectors.
Increases in ethanol fuel consumption in recent years have mitigated the growth in transportation sector emissions somewhat (emissions from energy inputs to ethanol production plants are counted in the industrial sector).
US GHG emissions per unit of Gross Domestic Product (GDP), or GHG-intensity, fell from 653 metric tons per million 2000 constant dollars of GDP (MTCO2e/$Million GDP) in 2005 to 625 MTCO2e /$Million GDP in 2006, a decline of 4.2%. Since 1990, the annual average decline in GHG-intensity has been 2.0%.
Total estimated US GHG emissions in 2006 consisted of 5,934.4 million metric tons of carbon dioxide (83.8% of total emissions), 605.1 MMTCO2e of methane (8.6% of total emissions), 378.6 MMTCO2e of nitrous oxide (5.4% of total emissions), and 157.6 MMTCO2e of hydrofluorocarbons (HFCs), perfluorocarbons (PFCs) and sulfur hexafluoride (SF6) (2.2% of total emissions).
Emissions of carbon dioxide from energy consumption and industrial processes, which had risen at an average annual rate of 1.2% per year from 1990 to 2005, declined by 1.8% in 2006. The decline in carbon dioxide emissions from 2005 to 2006 can be attributed to a 0.5% decline in overall energy demand and a decrease in the carbon intensity of electricity generation.
Favorable weather patterns, where both heating and cooling degree-days were lower in 2006 than 2005, and higher energy prices, were the primary causes of lower total energy consumption. The decline in carbon intensity of electricity generation was driven by increased use of natural gas, the least carbon-intensive fossil fuel, and greater reliance on non-fossil fuel energy sources.
Methane emissions, meanwhile, decreased by 0.4%, while nitrous oxide emissions rose by 2.9%. Emissions of HFCs, PFCs, and SF6, a group labeled collectively as “high-GWP gases” because their high heat trapping capabilities, fell by 2.2%.
The 2006 emissions decrease is only the third decline in annual emissions since 1990. Since 1990, US GHG emissions have grown at an average annual rate of 0.9%. GHG emissions in 2006 were 15.1% higher than those in 1990.
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Note how the number of on-road miles traveled is growing linearly by ~2.5% a year. This reflects mostly cargo transported around the world thanks to trade liberalization. No amount of tinkering with the fuel economy of passenger cars is going to make any difference to that. What you need is consumers who pay attention to how far what they buy has had to be shipped, especially consumables like food.
Another interesting tidbit is that a significant 6% of the total GWP of emissions from the transportation sector is due to gases other than CO2. This presumably includes high-altitude N2O from jet aircraft (the NO/NO2 emitted by piston engines is toxic but has little impact on global warming). Depending on how the data was compiled, those 6% may, however, include refrigerant leakage from automotive A/C units.
http://www.epa.gov/Ozone/title6/609/index.html
Posted by: Rafael Seidl | 28 November 2007 at 01:33 PM
Agreed. Which makes one wonder when we in NA and the west will begin to see the extreme cost of purchasing "low cost" products and manufacturing from emergent nations. Not only do we lose jobs and increase the GHG load, we are getting low quality products under the guise of good quality brands. This appears to be a net lose lose approach.
Posted by: gr | 28 November 2007 at 01:47 PM
With all that's happened with Chinese-sourced toys this year, I wonder if we're going to see a major shift in consumer sentiment. I have a young niece and nephew to buy presents for this year, but I refuse to purchase anything with "Made in China" on it.
And with the way the dollar is dropping, it might become more economically feasible to re-open factories here.
As for consumables, I read somewhere that grassfed New Zealand mutton shipped all the way to the UK is less CO2-intensive than domestically raised varieties. Food-miles don't seem to matter as much as farming methods. The whole chain must be considered, not just distance.
There are also methods for cutting fuel consumption by cargo ships, such as Skysail. Going to have to Google the company, since the comment spam apparently didn't like the URL.
Posted by: Cervus | 28 November 2007 at 02:37 PM
gr:
Are you serious?
Our Chinese HDTVs, Cordless Phones, PCs, Monitors, Printers and 100 other products work as good as any NA built units.
Our Japanese and Korean built vehicles work much better than our neighbours GM & Ford products. Same brand Japanese cars built in Japan work better than their USA/Canada counterpart.
My Malaysia built Gillette razors & blades work ok. etc etc.
Equivalent price NA built products are no better than those built in ASIA or Europe and often not as good.
Posted by: Harvey D | 28 November 2007 at 03:26 PM
Yeah gr, keep the truth out of the argument. What's a few million jobs and few million tons of Chinese power tools, clothes and toys to the equation when the true emissions of America's consumerism are safely tucked away under Chinese accounts.
Posted by: aussie paul | 28 November 2007 at 06:47 PM
Harvey,
I'm not saying all imports are a problem, only those we pay western prices for that are manufactured on a "lowest bid" basis. It is actually the responsibility of brand owners to protect their quality reputations. Japan and Korea both manufacture products outside their borders largely to maintain manufacturing trade balance.
This post is about US GHG reductions which I would think most would celebrate. I was concurring with Raphael's suggestion that western consumers need to confront the environmental damage associated with buying cheap imports from high-emission emergent nations.
Posted by: gr | 28 November 2007 at 07:12 PM
Rafael, you say that the steady increase in US on-road miles travelled "reflects mostly cargo transported around the world thanks to trade liberalization. No amount of tinkering with the fuel economy of passenger cars is going to make any difference to that." How can cargo transported around the world be mostly to blame for US ON-ROAD miles increasing?? That doesn't make any sense. The increase in miles seems to closely track the increase in US population. Perhaps that has something to do with it? And since passengar cars represent about half of emmissions from transportation, "tinkering" with their fuel economy most certainly WILL make a difference.
And how did this turn into a conservative talk radio rant about imports? These numbers don't reflect imports because they are DOMESTIC numbers. HELLO!!!!!
And even if we wanted to buy only North American made goods, how could we? Try finding a TV made in America... or a car that won't break down all the time. As long as the imports continue to offer superior quality at a better price people will keep buying them, as they should.
Posted by: Paul | 29 November 2007 at 10:29 AM
I dont understand how US Transport related emissions increased 0.5 % when the Oil consumption is down 1.3 % according to BP stats.
The only other possibility is that some of the Oil (which earlier went to Utilities/Heating) would have gone to Transport sector in 2006.
Many utilities around the world are switching from Oil to other sources especially Coal. So reducing GHG is a tough task unless we bring in Nuclear, Wind, Solar ...
Posted by: Max Reid | 29 November 2007 at 01:19 PM
@Rafael, Can you cite some data to back up the claim that goods movement is the main cause of VMT increase? That seems awfully high, I think passenger VMT is the greater cause. Moreover, most int'l goods movement occurs on marine and rail - I'd agree with re-logistics to shift more HDV loads to rail, but I'm not convinced that 'free trade' is a major cause of GHG emissions increase, or that we'd reduce GHGs by 'eating locally'.
Posted by: Brian T | 29 November 2007 at 01:37 PM
It is very difficult to come out with total (NET) local GHG variation without factoring in the role of all imports and exports.
Let's say that eastern USA imports a few million KWh from Canada and turns down a few coal fired power plants. Has USA effectively reduced GHG or transfered it to Canada?
The same applies when one million USA homes switch from heating oil to NG imported from Alberta.
Another example is when we import a few $ billion of car/trucks replacement parts from China. We effectively transfer a lot of GHG from NA to China.
Of course, we also export many products and that should also be factored in.
It is not a simple task but without accounting for imports/exports, local GHG variations do not mean that much any more.
Posted by: Harvey D | 29 November 2007 at 06:23 PM
"China has indicated it is not willing to undertake binding emissions reductions under a post-2012 regime, although it could take on voluntary commitments."
http://carbonplanet.com/home/country_emissions.php
Why not buy cheap stuff from unregulated totalitarians - it just brings on the apocalypse sooner!
Posted by: sulleny | 30 November 2007 at 06:25 PM