The C4 documantary about Krakatau states that the sound of the
explosion travelled around the earth 7 times. (Is that 3 1/2 times in
each direction BTW?)

Anyway, since we know that audible sound -even at those fairly low
frequencies, can not travel anywhere like that distance in normal
conditions. Any suggestions how it was conducted?

And how on earth did that light house keeper manage to survive the
tsunami when the wave was estimated to be 40m high?

"Weatherlawyer" wrote in message
ps.com...
The C4 documantary about Krakatau states that the sound of the
explosion travelled around the earth 7 times. (Is that 3 1/2 times in
each direction BTW?)

No in all directions.

Karatepe wrote:

And how on earth did that light house keeper manage to survive the
tsunami when the wave was estimated to be 40m high?

It's only water. If he survived the surge and was not battered by or
against something solid, it's only a matter of holding your breath.
Even if he had his lungs compressed, the frequency of a tidal wave
might have given him a few minutes to half an hour before the next
wave.

Most people that are hurt are trapped in the melee or carried out with
the debris. The chances are he was carried clear across the shoreline.

Lawrence Jenkins wrote:

The C4 documantary about Krakatau states that the sound of the
explosion travelled around the earth 7 times. (Is that 3 1/2 times in
each direction BTW?)

No in all directions.

I am no expert, but would a particularly large explosion such as this
cause the Earth to reverberate?

--
Jonathan Stott
Canterbury Weather: http://www.canterburyweather.co.uk/
Reverse my e-mail address to reply by e-mail

Isn't this in the wrong NG??

Jim.


"Weatherlawyer" wrote in message
ps.com...
The C4 documantary about Krakatau states that the sound of the
explosion travelled around the earth 7 times. (Is that 3 1/2 times in
each direction BTW?)

Anyway, since we know that audible sound -even at those fairly low
frequencies, can not travel anywhere like that distance in normal
conditions. Any suggestions how it was conducted?

In article . com,
pen writes:
Well possibly, except that I saw a snippet in New Scientist a couple of
weeks ago which said that the dust from the Krakatoa eruption hung
around in the atmsophere for up to a century, with a measurable effect
on climate.

I haven't read the article, but that doesn't sound very plausible to me.
I thought that of the order of 2-3 years was the generally accepted
figure.

(ISTR that the year after the eruption was known as "the
year without a summer").

That was actually 1816, following another volcanic eruption.

So how much of global warming is attributable
to human activity and how much to relative lack of volcanic activity?

I would prefer not to believe in anthropogenic global warning, but I've
seen enough evidence to make me a reluctant convert.

Perhaps we should be trying to help one or two isolated ones along -
not sure quite how you'd do this!

Probably just as well that we can't.
--
John Hall
"Banking was conceived in iniquity and born in sin"
attributed to Sir Josiah Stamp,
a former director of the Bank of England

"John Hall" wrote in message
...
In article . com,
pen writes:
Well possibly, except that I saw a snippet in New Scientist a couple of
weeks ago which said that the dust from the Krakatoa eruption hung
around in the atmsophere for up to a century, with a measurable effect
on climate.

I haven't read the article, but that doesn't sound very plausible to me.
I thought that of the order of 2-3 years was the generally accepted
figure.

(ISTR that the year after the eruption was known as "the
year without a summer").

That was actually 1816, following another volcanic eruption.

So how much of global warming is attributable
to human activity and how much to relative lack of volcanic activity?

I would prefer not to believe in anthropogenic global warning, but I've
seen enough evidence to make me a reluctant convert.

Perhaps we should be trying to help one or two isolated ones along -
not sure quite how you'd do this!

Probably just as well that we can't.
--

Yep, 1816 "The year without a summer" caused by the Tambora eruption in
1815.
Apparently the Shelly's , Byron and his physician Dr William Polidori spent
many an addled evening in a rented Villa on the banks of Lake Geneva. The
weather was so cool, wet, foul and punctuated with continuous thunder
storms, that the gloom is thought to have contributed to Mary Shelley's
inspiration for Frankenstein!!!!!!!
Nope the name is Franken stein.
Put the candle back.....

Jim Smith wrote:

Isn't this in the wrong NG??

No. I admit to being way ahead of my time on most things but this case
is about the pipe that must have existed that conducted the sound
through the atmosphere. (Assuming it came via the atmosphere.)

There would have been massive cyclonic activity concurrent with the
series of events -if that helps. They would have been in the shadow
zone, a band roughly 15 degrees either side of an arc at 120 degrees
around the epicentre.

Dates to check:

Beginning 20 May 1883, three months before the final explosion, steam
venting began to occur on a regular basis.

By early August, three vents were regularly erupting on Krakatoa; tides
in the vicinity were unusually high,

11 August saw the onset of larger eruptions, with ashy plumes being
emitted from as many as eleven vents.

On 24 August, eruptions further intensified, and the cataclysmic phase
began on Sunday 26 August, near midday.

The 27 August eruptions occurred at 5:30 a.m., 6:42 a.m., 8:20 a.m.,
and 10:02 a.m. local time.

By 28 August, Krakatoa was quiet again. Ash clouds caused by the
eruption blocked sunlight for a couple of days within the area.

http://en.wikipedia.org/wiki/Krakatoa#The_1883_eruption

Nice of it to stay in the season of North Atlantic hurricanes. That
should make tracing records easier than they might have been.

Well, that's all from the genius; now onto the clerks and number
crunchers. And/or sundry midgets. No offence. I couldn't do your job. I
I respect your abilitiies but well, no...

I keep forgetting to be humble.. sorry.

I've looked it up on their website - 9 Feb 2006:

"WHEN the Indonesian volcano Krakatoa erupted in 1883, sending 25 cubic
kilometres of rock and ash into the air, it did more than generate the
loudest sound ever recorded. It also cooled the world's oceans and
suppressed rises in sea level for decades afterwards.

"Peter Gleckler of the Lawrence Livermore National Laboratory in
California and colleagues compared climate models that included
volcanoes with those that did not. To their surprise they found that
volcanoes seem to have a cooling effect on the oceans that lasts for up
to a century after an eruption. The cooling effect of Krakatoa lasted
well into the 20th century, says Gleckler.

"Big volcanoes inject ash high into the atmosphere and block out
sunlight for months or even years, which cools ocean surface waters
(Nature, vol 439, p 675).

"However, global warming appears to have diminished this long-term
effect, he says."

I'm not into global warming denial, just wondering how much effect in
the 20th century was down to starting from a Krakatoa induced low
point. And I was also trying to remember when the last major volcano
blew its top - was it Mt St Helens?