Isn't this thread a little "apples and oranges"?
I don't see much to compare between a Hummer
and a Prius.

I have an '01 Prius with about 133K miles on it, and
it feels like I've just passed the initial break-in period.

Anyone have a good idea where I might sell it? I'm
about ready to move up to the current generation Prius.
i.e. '04 or newer...

Thanks!                                           - Greg

 Guru Says GOODBYE To Search Engines
http://1stBe.com/goodbye-search-engines

Let's run some numbers. (My apologies to the UK people, who I understand
don't have the same meaning of billion, trillion and quadrillion we do in
the US.) It sounds like you assume Arctic melting is the result of rising
global temperatures, which are in turn the result of rising CO2 levels,
driven by burning fossil fuels. We will see those are all dubious
assumptions, but we'll get out our calculators anyway.

I'm not sure what your question is asking; whether you are picturing
everybody uniformly driving either a Prius or a Hummer, or if all Prius cars
were traded for Hummers. It's unclear how many Hummers of various styles are
in circulation, and I don't see all-time totals in MRV's postings of Prius
sales in the US. Let's go on the high side of either with a million vehicles
to be changed from Prius to Hummer. The Hummer is EPA rated 15 mpg in town,
19 highway. For ease and conservatism, let's use 10 mpg. Let's also assume
each will be driven an average of 20K miles per year, for a total of 2000
gallons per vehicle and 2 billion gallons for the million vehicles per year.
The EPA fuel economy is only about 25% of the Prius EPA rating, so we can
estimate a million Hummers would consume 1.5 billion gallons per year more
than a million Prius.

In the US, we consume about 7.3 trillion barrels of petroleum products per
year(http://tinyurl.com/2ytmrj), about 45% of that is used as gasoline
(http://tinyurl.com/y5g7ed).  At 55 gallons per barrel, that amounts to
about 400 trillion gallons of petroleum and a little short of 200 trillion
gallons of gasoline. By changing a million Prius driven 20K miles per year
in the city to Hummers we would increase gasoline consumption in the US by
about 0.00075%, and increase US oil consumption by about 0.00035%. The world
petroleum consumption is about 1600 trillion gallons per year
(http://tinyurl.com/2roxfx), so the effect on world oil consumption would be
about 0.0001%... right at one part per million.

That's not all the fossil carbon in play. Coal consumption worldwide is
about 6 billion tons per year (http://tinyurl.com/3dhyld), or about 12
trillion pounds. Since petroleum is composed of alkanes, we can say the 6
lbs/gallon approximate weight is carbon and worldwide oil consumption is 10
quadrillion pounds. (Natural gas is similarly minor:
http://tinyurl.com/34pu6w and http://tinyurl.com/2qo673.) Those numbers
don't dent the petroleum numbers but still dwarf the million Hummers by a
factor of 10,000.

There are no proposed solutions that would change the shape of things to
come in atmospheric CO2 levels, only the timeline. Since atmospheric CO2 is
still rising 0.4% per year (http://tinyurl.com/yvuq9n), reducing the
worldwide fossil carbon load by .0001% would reduce the timeline by about 2
1/2 hours per year.

However, we also know the majority of the excess CO2 comes from surface
sources. The "Industrial Effect" of C14 dilution by fossil carbon was
discovered by Hans Suess in 1955 (http://tinyurl.com/z43h9). He found that
the C14 signal was diluted a bit over 2% with respect to 1898 levels. About
that time, the Mauna Loa Observatory had begun monitoring CO2 levels and
found they were 315 ppm, up 13% from 278 ppm (http://tinyurl.com/yvuq9n). 7
ppm of the 37 ppm were fossil in origin (no C14), leaving 80% of the excess
CO2 to be from surface sources. Since then atmospheric thermonuclear testing
has obscured the C14 record (http://tinyurl.com/z43h9) so we don't have
current data.

What is the measured effect of CO2 on climate? There is no usable supporting
data - the methodology is not practical - but there are indications there
may actually be no effect (http://tinyurl.com/2lcc45). The authors "prefer"
that their data shows the model they were using was incorrect, but that is
not science, just wishes.

Is the Earth warming? Good question. In a world dominated by water and ice,
that is probably unknowable. Temperatures are only loosely related to the
question of heat (enthalpy) retention, for the same reason a glass of water
to which ice has been added can gain heat and drop in temperature on a
summer day. Don't even bother talking about land temperatures - that is
entirely the realm of regional effects. Given that two thirds of the world
is covered by water and that water has 5 times the heat capacity of silica
(the most common rock), the oceans would have to be no more than knee deep
for land temperatures to be important.

Is Arctic thawing the result of global warming? There is no reason to
believe so. The regional weather phenomenon known as the Arctic Oscillation
(National Geographic magazine January 2004, or http://tinyurl.com/296l3r) is
well known to be directly responsible. There is no credible evidence to
associate AO with global temperatures; the same theories work equally well
if you substitute "witchcraft" for "global warming." Note that much of the
Antarctic has cooled over the last 30 years (http://tinyurl.com/2d7p8d).

So... in the event that Arctic melting is caused somehow by global warming,
and that the earth is actually warming, and that rising atmospheric CO2 is
the primary cause of that warming, and that fossil fuels are primarily
responsible for the rising CO2... changing a million Prius to Hummers would
speed the melting by 2.5 hours per year.

Mike