Archives

http://www.cleanmpg.com/photos/data/2/AmericanFlag.jpg If Congress does not act to control greenhouse gas pollution the administration will do so. (http://greeninc.blogs.nytimes.com/2009/12/07/epa-sets-carbon-crackdown/)

http://www.cleanmpg.com/photos/data/501/co2.jpgJohn M. Broder - BLOGS (http://greeninc.blogs.nytimes.com) - Dec 7, 2009

Will American cars have CO2 limits like the EU? --Ed.

The Environmental Protection Agency on Monday will finalize its determination that greenhouse gases pose a danger to human health and the environment, paving the way for regulation of carbon dioxide emissions from vehicles, power plants, factories refineries and other major sources.

The move gives President Obama a significant tool to combat the gases blamed for the heating of the planet even while Congress remains stalled on economy-wide global warming legislation.... http://greeninc.blogs.nytimes.com/2009/12/07/epa-sets-carbon-crackdown/

If the EPA is going to start regulating all greenhouse gases, in addition to the more well known greenhouse gases, carbon dioxide and methane, does this mean they also going to regulate the emissions of one of the most potent greenhouse gases of all, water vapor. If so, then hydrogen cars are in trouble since their exhaust is 100% water vapor. Industrial emitters of water vapor include evaporative cooling towers, salt pans, sewage treatment plants, and the cooling ponds for power generators. Agricultural water vapor emitters include greenhouse swamp coolers, spray irrigators, all irrigated croplands, and if they really wanted to get strict about it, all cultivated crops since all plants emit water vapor. Suburban water vapor emitters include golf courses, lawns, and any garden water features like ornamental ponds with their fountains and waterfalls. They would also need to regulate any man-made bodies of water since their creation increases water vapor emissions.

I can support this, IFF (if and only if) it means more focus on MPG and less on ppm emissions. It's completely outrageous that a 50+ mpg clean diesel car can't meet emissions, but a 1-ton commuter truck is just fine.

If the EPA is going to start regulating all greenhouse gases, in addition to the more well known greenhouse gases, carbon dioxide and methane, does this mean they also going to regulate the emissions of one of the most potent greenhouse gases of all, water vapor. If so, then hydrogen cars are in trouble since their exhaust is 100% water vapor. Industrial emitters of water vapor include evaporative cooling towers, salt pans, sewage treatment plants, and the cooling ponds for power generators. Agricultural water vapor emitters include greenhouse swamp coolers, spray irrigators, all irrigated croplands, and if they really wanted to get strict about it, all cultivated crops since all plants emit water vapor. Suburban water vapor emitters include golf courses, lawns, and any garden water features like ornamental ponds with their fountains and waterfalls. They would also need to regulate any man-made bodies of water since their creation increases water vapor emissions.

My understanding is that while having a large effect, atmospheric water vapor's life cycle is short so it's not a significant long-term concern.

My understanding is that while having a large effect, atmospheric water vapor's life cycle is short so it's not a significant long-term concern.
I've heard this as well. From what I've read, water vapor does not have the same climate forcing ability that carbon dioxide has, despite still being a greenhouse gas.

The biggest emitter of water vapor is plant life. I just don't buy the argument that water vapor is bad. The reverse is true, one reason we're in deep doo doo is the destruction of the rain forest in South America and other places.

I don't know if it's just me, but I resent it when some self-important nincompoop drives by me on the highway spewing 4 or 5 times as much CO2 as I do. There are things we can control and CO2 emissions from vehicles are a prime target to focus on.

Harry

I'd be content in the EPA simply setting standards on CO2 emissions just like they do on fuel economy. Various greenwashers brag some 15mpg vehicle is "clean", but including CO2 into the equation makes it more truthful. ;)

Co2 itself doesn't directly cause most of the predicted warming, it is feedbacks like increased water vapor that are supposed to make matters worse, so yes water vapor is a problem the EPA should address.

"The perspective by Dessler and co-author Steven Sherwood of the Climate Change Research Centre at the University of New South Wales is published in the journal Science. In the article, they review and summarize the peer-reviewed evidence in support of a strong water vapor feedback and conclude that the evidence supporting it is overwhelming.

“For years, there was a debate over this mechanism, with some even questioning if the water vapor feedback existed at all. But recent work on this feedback has moved its existence and strength beyond argument,” Dessler adds.

Predictions of significant global warming over the next 100 years by climate models require a strong water vapor feedback."

http://www.sciencedaily.com/releases/2009/02/090219152132.htm

The big question is who broadly the EPA will regulate on greenhouse gases. Tailpipe emissions is one thing, but if extended to stuff like belching cows, the economic impact will be considerable.

Talk shows already have likened this to martial law.

Burning fossil fuel accounted for 94.2% of carbon dioxide emissions in 2006. Emissions are measured in teragrams of carbon dioxide equivalents:http://images.usatoday.com/_common/_images/ipr/grey.gif

Total carbon dioxide emissions 5,983.1


http://images.usatoday.com/_common/_images/ipr/grey.gifFossil fuel combustion 5,637.9

http://images.usatoday.com/_common/_images/ipr/grey.gif> Electricity generation 2,328.2

http://images.usatoday.com/_common/_images/ipr/grey.gif> Transportation 1,856.0

http://images.usatoday.com/_common/_images/ipr/grey.gif> Industrial 862.2

http://images.usatoday.com/_common/_images/ipr/grey.gif> Residential 326.5

http://images.usatoday.com/_common/_images/ipr/grey.gif> Commercial 210.1
http://images.usatoday.com/_common/_images/ipr/grey.gifSource: Environmental Protection Agency

If the EPA is going to start regulating all greenhouse gases, in addition to the more well known greenhouse gases, carbon dioxide and methane, does this mean they also going to regulate the emissions of one of the most potent greenhouse gases of all, water vapor. If so, then hydrogen cars are in trouble since their exhaust is 100% water vapor. ...

The figures I see are that the average atmospheric residence times are 9 days for water vapor, over a century for CO2. Per amount of energy derived from dumping these gases into the atmosphere, the CO2-emitting process causes three orders of magnitude more GW impact.