Slicing the greenhouse gas pie: Where from?

In the previous post, I described which gases are important and what activities they come from. But we can also learn a lot by looking at regional patterns in how those gases are emitted.

For example, most deforestation occurs in poor tropical countries (in fact, in many of these countries deforestation is a much larger source of CO2 than fossil fuel use). In contrast, most CO2 emissions from fossil fuel use come from the developed countries.

As I described in an earlier post, the U.S. is the largest emitter in the world, both today and historically. Next let’s take a closer look at the U.S. greenhouse gas pie.

As one might expect in a developed country, virtually all our CO2 emissions come from burning fossil fuels. We use relatively more natural gas than the rest of the world – which is good because natural gas is the cleanest of the fossil fuels. The percentages are: about 40 percent coal, about 40 percent petroleum, and about 20 percent natural gas. Worldwide, deforestation is a net source of CO2, but in the U.S., forests and urban trees are growing. They are taking CO2 out of the atmosphere and storing it. That growth cancels out about 11 percent of U.S. fossil fuel emissions.

Forty percent of our country’s CO2 emissions come from electricity generation. Half of our electricity comes from coal-fired power plants, which produce 32 percent of America’s CO2 emissions. Because of that, utilities will play a huge role in our fight against global warming, but everyone will need to cut emissions because every sector contributes to greenhouse gas pollution:
U S. greenhouse gas pie: Sliced by economic sector

It is interesting to note that residential and commercial emissions – coming from our homes and offices – together make up almost 40 percent of our emissions. What the chart doesn’t show is that commercial and residential emissions are growing about twice as fast as the overall average.

These statistics suggest that there are multiple sources to worry about in our fight against global warming. Clearly, coal is a major challenge – almost one-third of our emissions come from coal-fired power plants. But the good news is that there are clean coal technologies that would allow us to use our huge coal reserves without harming the climate.

Transportation is another biggie – also about one-third of our emissions. Here again there are solutions – more fuel efficient cars come to mind. And for commercial and residential sectors, building green buildings and improving the efficiency of our existing ones will help stem the flow of greenhouse emissions.

As I’ve said before, it’s not going to be one silver bullet; the solution is going to be more like silver buckshot.

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  1. Globalwhat?
    Posted April 26, 2007 at 7:02 pm | Permalink

    Does anybody read the news about global freezing going on today? In the past week I have read of major crop failures in Australia, New Zealand, in the southern Hemisphere, and don’t forget a major crop failure due to frost is hitting the US east of the Continental Divide, killing grapes, and fruits, and even winter wheat. Then consider all the ships off New Foundland locked in ICE so strong Ice Breakers cannot extracate the vessels. I guess if anyone reported this stuff in the media some might question global warming. Does anyone remember the 1970s when the “scientists” predicted another ice age would destroy our planet? Those that did not buy it were painted as crazies. Will this ever end or is it just that each generation gets fed its bunch of baloney and believes it is uniquely qualified to understand the weather, even though a prediction for next week is only 50/50 or less.

  2. Lisa Moore
    Posted April 27, 2007 at 2:45 pm | Permalink

    These sorts of events can be confusing when everyone is talking about global warming. But as this earlier post explains, short-term local is different from long-term global.

    For the same reason, climate modeling is different from weather prediction. Scientists can — and do! — check how well climate models perform, by comparing model results to actual climate observations. [The graph shows actual global temperatures (black line), model results when models only consider natural factors like solar energy and volcanoes (blue) and model results when models include natural and man-made factors like greenhouse gases (red).] Climate models do a good job reproducing actual climate, but only when they include the effects of greenhouse gases.

    As for the 1970s ice age story, see Argument #4 in this document [PDF] that explains how scientists know that humans are responsible for global warming.

  3. wwwgator
    Posted April 28, 2007 at 1:19 am | Permalink

    Are you Kidding Lisa?
    I know you try to preach, but please get your “facts” correct, that’s why they are called facts.
    Your Global Warming Attributes you link to ( states that “incontrovetable answer” that CO2 emmisions are predominately from the burning of fossil fuels. Did the science change since high school? HUMANS expel carbon DIOxide (co2), fossil predominately Carbon MONOxide (co1). You warming zealots constantly ignore the fact of O3 (ozone) Remember back in the late 70’s when the hole was getting bigger and Gamma radiation from the sun was going to bake us alive? We eliminated the CFC’s to stop depleating the ozone, and now we have too much! It’s emmision is controlled by the EPA!
    Indusrty is greatly regulated in the byproduct release of O3. Ozone action days, increased health warnings to stay inside, and guess what, the hole is still there, no bigger , no smaller.
    If we had any ability to affect this enviorment, do you honestly think we would use it for more rain where needed, longer growing seasons for the farmers?
    In Wisconsin years ago, where I am at this very moment, stood a glacial edge 3 miles tall. (unless that mis-information our teachers preached for 12 years) Why did it melt? where did the water go? Sheer volume of that much ice would have covered the entire land mass. (That is if the laws of physics changed about ice being upto 3X volume displacement of liquid water ( we have the pot holes to prove it is still valid).

    Let me ask you 3 honest questions:
    1 What is the temperature supposed to be at?
    2 Who decided it?
    3 Has anybody checked the temperatures of other planets?

    I find it very hard for anyone belonging to the Church Of Global Warming to answer any of the above questions. Seriously, would you honestly answer these? All I ever get is “There is no more debate, this is real”
    Please truthfully answer these.
    Then I might start seriously consider if this is really caused by us.

  4. Posted May 1, 2007 at 1:04 pm | Permalink

    For answers to your first and second questions, see my post “How Warm is Too Warm“.

    Re your third question… Researchers do look at temperatures on other planets, but this isn’t relevant to what’s happening here on Earth. The warming on Earth is demonstrably due to human activity (see my article on why you should believe the IPCC report).

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