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Re: Dissecting CFLs



"D&SW" <d&sw@xxxxxxxxxxx> wrote in message
news:rDZai.3560$4t5.2300@xxxxxxxxxxx
> No, actually the earth cleans itself remarkably well.  Pinatubo was second
> to Krakatoa in size and probably pollution. The skies were clear of all
> Pinatubo evidence in less than a month.

I'm sorry, but that's simply not correct.

It's pretty well-established, "D," from dendochronological evidence (tree
rings) to ice cores, that Krakatoa-sized eruptions inject debris into the
atmosphere for years.  The darkened skies cause poor tree growth and a
narrowing of the tree rings during that time.  The debris that slowly falls
to earth settles on the icepack like an endless layer cake, storing the
history of earth's atmosphere almost like a book.  Every eruption has a
unique fingerprint.  Modern techniques make it very easy to determine where
the ash in ice cores came from.

I'd like to know the source of your information because as far as I know,
there was never any doubt about the ability of massive volcanoes to effect
the atmosphere for years.

In fact, the largest of them, the supervolcanoes, have the power to
completely alter the composition of the atmosphere like the Siberian Traps
eruptions:

http://en.wikipedia.org/wiki/Siberian_Traps

that covered 77,000 square miles with lava (that's the size of the state of
Nebraska).  Some believe this eruption was the trigger for the most massive
dieout in earth's history, the Permian-Triassic extinction event and that it
doubled the amount of CO2 in earth's atmosphere.

There's a supervolcano under Yellowstone Park with a caldera large enough to
see from space.

http://www.thisoldearth.net/thisoldblog/ has an interesting article about
it:

<<So what would happen if another catastrophic eruption took place today?
Bill McGuire, professor of geohazards at the Benfield Greig Hazard Research
Centre at the University College of London said "magma would be flung 50
kilometers into the atmosphere. Within a thousand kilometers virtually all
life would be killed by falling ash, lava flows and the sheer explosive
force of the eruption. One thousand cubic kilometers of lava would pour out
of the volcano, enough to coat the whole USA with a layer 5 inches thick [?]
the bitter cold of Volcanic Winter to Planet Earth. Mankind may become
extinct." >>

Anyway, back to your original comment, here's one site that describes how
long volcanic ash can stay aloft:

<<When a volcano erupts it will sometimes eject material known as tephra,
i.e. rock fragments, into the atmosphere. . . .The smallest particles, which
are less than 0.0025 inches, can stay in the atmosphere for two or three
years after a volcanic eruption. Sometimes these particles produce fantastic
sunsets, such as was seen after the eruptions of Krakatau in 1883 and
Pinatubo in 1991. Some scientists believe that these particles may
contribute to global warming. >>

http://www.pdc.org/iweb/volcano_hazards.jsp  (Pacific Disaster Center)

I don't think it would be hard to find many other sites that say the same
thing.  Let's see:

http://en.wikipedia.org/wiki/Mount_Pinatubo says:

<<This very large stratospheric injection resulted in a reduction in the
normal amount of sunlight reaching the earth's surface by up to 5% (see
figure). This led to a decrease in northern hemisphere average temperatures
of 0.5?0.6 °C (0.9?1.1 °F), and a global fall of about 0.4 °C (0.7 °F). At
the same time, the temperature in the stratosphere rose to several degrees
higher than normal, due to absorption of radiation by the aerosols. The
stratospheric cloud from the eruption persisted in the atmosphere for three
years after the eruption.>>

Pinatubo's visible ash cloud may have "washed out" early because Typhoon
Yunya struck the Phillipines right at the climax but the very fine ash in
the stratosphere took a long time to come back down.

Sorry "D", but I still think my remark was correct.  Massive volcanic
eruptions can darken the sky for years.  But I'm not ruling out the
possibility you've found a source that claims differently.

--
Bobby G.


>
> "Robert Green" <ROBERT_GREEN1963@xxxxxxxxx> wrote in message
> news:WsCdnVl42aFBjf7bnZ2dnUVZ_rGinZ2d@xxxxxxxxxx
> > "Dave Houston" <nobody@xxxxxxxxxxxx> wrote in message
> > news:4662ec8b.23541937@xxxxxxxxxxxxxxxx
> >> "Robert Green" <ROBERT_GREEN1963@xxxxxxxxx> wrote:
> >>
> >> >I was thinking of making a jig from a 2 by 4 scraps with two v's cut
so
> > that
> >> >I could rotate the base of the bulb around against a 1/2" Dremel
cutoff
> >> >wheel at a fixed distance, sort of like a can opener.
> >>
> >> Are you insane? Cutting them open will void the warranty. ;-)
> >>
> >> AP has another coal story this morning.
> >>
> >>
> >
http://hosted.ap.org/dynamic/stories/G/GLOBAL_WARMING_STATES?SITE=AP&SECTION
> > =HOME&TEMPLATE=DEFAULT&CTIME=2007-06-02-12-45-20
> >
> > That article confirms something I've said before.  In a state like
Idaho,
> > where electricity comes from hydro, the CFL equation falls flat on its
> > face.
> > They add mercury to the environment without providing any "offset" at
the
> > stack because there IS no stack.
> >
> > More than that, the article makes it clear that the biggest gains are
> > going
> > to come from regulations limiting what coal plants can expel into the
air.
> > It's going to make power more expensive, at least in the short run, but
> > the
> > paybacks will be real and enormous.  That much is clear from the record
of
> > states that have taken the right steps.  Dribs and drabs won't clean the
> > air
> > and neither will the commercial sector because there's no profit in it.
> > That's when governments are supposed to step up and do the right thing.
> >
> > There was an interesting sidebar, too:
> >
> > NASA Chief Not Worried About Climate
> >
http://hosted.ap.org/dynamic/stories/N/NASA_CLIMATE_CHANGE?SITE=AP&SECTION=H
> > OME&TEMPLATE=DEFAULT&CTIME=2007-05-31-20-30-15
> >
> > It makes the point that we're rather arrogant in assuming now that man
> > rules
> > the planet, all climate change must cease.  All it would take is another
> > Krakatoa-sized eruption in the world to turn on some serious global air
> > conditioning.  The soot from such eruptions typically blocks significant
> > amounts of sunlight for years and years.
> >
> > --
> > Bobby G.
> >
> >
> >
>
>




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