A several kilogram block of ice fell through the roof of an Auckland house
last evening. Said to be travelling at 450 Km per hour.


Linkname: Scientist says ice meteors a sign of climate change - 10/1/2002
- ENN.com
http://www.enn.com/news/wire-stories.../reu_48569.asp


Scientist says ice meteors a sign of climate change

Tuesday, October 01, 2002
By Emma Ross-Thomas, Reuters
[reuters2.gif]

MADRID, Spain -- A Spanish scientist says global warming may be to blame
for giant blocks of ice that fall from clear skies and rip gaping holes
in cars and houses.

Jesus Martinez-Frias has spent the last two-and-a-half years
investigating so-called megacryometeors -- ice meteors -- which tend to
weigh more than 22 pounds and have been known to leave five-foot holes in
houses. He fears the formation of these hailstonelike blocks on clear
days could be a worrying symptom of climate change.

"I'm not worried that a block of ice might fall on your head ... but that
great blocks of ice are forming where they shouldn't exist," said
Martinez-Frias, director of planetary geography at Spain's Astrobiology
Center in Madrid. "Components of the atmosphere like ozone and water are
changing in different levels of the atmosphere.... We think these signs
could be evidence of climate change," he said.

While Martinez-Frias said he was far from certain as to why the ice
meteors formed, he said they were neither hoaxes nor blocks of ice
falling from the bars or bathrooms of passing aircraft, as skeptics have
suggested.

"We're not talking about hoaxes," Martinez-Frias said. "It's very easy to
tell real and false ice blocks apart. It's not water from airplane
toilets.... It's isotopic composition bears the signature ... of Iberian
rain."

SMASHING WINDSHIELDS

Ice clouds made from crystallized vapor trails of aircraft are well known
to pilots, but Martinez-Frias suggests that because global warming
involves one level of the atmosphere getting colder while another gets
hotter, some ice clouds now remain longer.

Their centers then fall through the atmosphere, bouncing and gathering
mass, to end up smashing through a car windshields or, more frequently,
landing softly in a field, he suggested.

The first megacryometeor found this year in Spain -- by a startled farmer
riding his tractor in Soria -- weighed 35.27 pounds. Three others were
found later, bringing the world total over the last decade to more than
50. But Martinez-Frias said only around one-fifth of the ice meteors are
ever found.

An ice meteor weighing around 440 pounds has been found in Brazil,
Martinez-Frias said. Other blocks have been found in Mexico and
Australia.

Some scientists doubt whether hail can form on a clear day. "Solid ice
cannot form in the absence of thick, highly visible clouds," Charles
Knight, a hail expert at the University Corporation for Atmospheric
Research in Boulder, Colo., was quoted as saying in a supplement of
Science journal.

But geologist Roger Buick of the University of Washington in Seattle told
the same publication that a model created by Martinez-Frias and his team
showing ice can form on a clear day was an "important advance in that it
thoroughly documents and provides an explanation for a spectacular
phenomenon."

Copyright 2002, Reuters
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In sci.geo.meteorology Brian Sandle wrote:


While Martinez-Frias said he was far from certain as to why the ice
meteors formed, he said they were neither hoaxes nor blocks of ice
falling from the bars or bathrooms of passing aircraft, as skeptics have
suggested.

http://www.nzherald.co.nz/storydispl...ection=general

gives:
****
Auckland University physics lecturer David Krofcheck said a 5kg block falling
from a plane at 3050m would hit the ground at 400km/h.

"It wouldn't have had much friction, so there would have been plenty of
energy to punch a hole through the roof.
****

Or about 100 meters per second. Since the acceleration due to gravity is 10
that means it would only have been in the air for 10 seconds. That would not
be enough time for ice to form. If it came out of or off a plane it would
have to have been ice already.

Occam's Razor applies well here - that is one should not increase, beyond
what is necessary, the number of entities required to explain anything, or
alternatively the most simple answer is probably the most likely.

It's much more likely that this ice came from an aircraft than an
atmospheric anomaly, decribed by some obscure theory only demonstrated in a
model with no empirical evidence to support it.

"Brian Sandle" wrote in message
...
A several kilogram block of ice fell through the roof of an Auckland house
last evening. Said to be travelling at 450 Km per hour.


Linkname: Scientist says ice meteors a sign of climate change -
10/1/2002
- ENN.com
http://www.enn.com/news/wire-stories.../reu_48569.asp


Scientist says ice meteors a sign of climate change

Tuesday, October 01, 2002
By Emma Ross-Thomas, Reuters
[reuters2.gif]

MADRID, Spain -- A Spanish scientist says global warming may be to
blame
for giant blocks of ice that fall from clear skies and rip gaping holes
in cars and houses.

Jesus Martinez-Frias has spent the last two-and-a-half years
investigating so-called megacryometeors -- ice meteors -- which tend to
weigh more than 22 pounds and have been known to leave five-foot holes
in
houses. He fears the formation of these hailstonelike blocks on clear
days could be a worrying symptom of climate change.

"I'm not worried that a block of ice might fall on your head ... but
that
great blocks of ice are forming where they shouldn't exist," said
Martinez-Frias, director of planetary geography at Spain's Astrobiology
Center in Madrid. "Components of the atmosphere like ozone and water
are
changing in different levels of the atmosphere.... We think these signs
could be evidence of climate change," he said.

While Martinez-Frias said he was far from certain as to why the ice
meteors formed, he said they were neither hoaxes nor blocks of ice
falling from the bars or bathrooms of passing aircraft, as skeptics
have
suggested.

"We're not talking about hoaxes," Martinez-Frias said. "It's very easy
to
tell real and false ice blocks apart. It's not water from airplane
toilets.... It's isotopic composition bears the signature ... of
Iberian
rain."

SMASHING WINDSHIELDS

Ice clouds made from crystallized vapor trails of aircraft are well
known
to pilots, but Martinez-Frias suggests that because global warming
involves one level of the atmosphere getting colder while another gets
hotter, some ice clouds now remain longer.

Their centers then fall through the atmosphere, bouncing and gathering
mass, to end up smashing through a car windshields or, more frequently,
landing softly in a field, he suggested.

The first megacryometeor found this year in Spain -- by a startled
farmer
riding his tractor in Soria -- weighed 35.27 pounds. Three others were
found later, bringing the world total over the last decade to more than
50. But Martinez-Frias said only around one-fifth of the ice meteors
are
ever found.

An ice meteor weighing around 440 pounds has been found in Brazil,
Martinez-Frias said. Other blocks have been found in Mexico and
Australia.

Some scientists doubt whether hail can form on a clear day. "Solid ice
cannot form in the absence of thick, highly visible clouds," Charles
Knight, a hail expert at the University Corporation for Atmospheric
Research in Boulder, Colo., was quoted as saying in a supplement of
Science journal.

But geologist Roger Buick of the University of Washington in Seattle
told
the same publication that a model created by Martinez-Frias and his
team
showing ice can form on a clear day was an "important advance in that
it
thoroughly documents and provides an explanation for a spectacular
phenomenon."

Copyright 2002, Reuters
All Rights Reserved
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Become
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Rupert wrote:
Occam's Razor applies well here - that is one should not increase, beyond
what is necessary, the number of entities required to explain anything, or
alternatively the most simple answer is probably the most likely.

It's much more likely that this ice came from an aircraft than an
atmospheric anomaly, decribed by some obscure theory only demonstrated in a
model with no empirical evidence to support it.

There is the isotopic constitution which would show whether the water is from
terrestrial sources, via an aircraft tank, or from the atmosphere.

Brian Sandle wrote:
In sci.geo.meteorology Brian Sandle wrote:


While Martinez-Frias said he was far from certain as to why the ice
meteors formed, he said they were neither hoaxes nor blocks of ice
falling from the bars or bathrooms of passing aircraft, as skeptics have
suggested.

http://www.nzherald.co.nz/storydispl...ection=general

gives:
****
Auckland University physics lecturer David Krofcheck said a 5kg block falling
from a plane at 3050m would hit the ground at 400km/h.

"It wouldn't have had much friction, so there would have been plenty of
energy to punch a hole through the roof.
****

Or about 100 meters per second. Since the acceleration due to gravity is 10
that means it would only have been in the air for 10 seconds. That would not
be enough time for ice to form. If it came out of or off a plane it would
have to have been ice already.

Radio New Zealand Summer Report has given that it happened to a neighbouring
property a week ago, that time a number of blocks but nothing large enough to
do damage.

So the events are probably connected.

What is the largest block of ice that can form on a plane?

To get a downward velocity of that amount they would only have to drop from
600 metres. Are planes shaking a bit or warming enough over Auckland that ice
falls off?

I see a vapour trail going high over Christchurch on a regular basis. Does
anything like that happen over Auckland? Refer the well-known ice trails.


http://hyperphysics.phy-astr.gsu.edu/hbase/airfri2.htm

Terminal Velocity Examples

Falling object Mass Area Terminal velocity
Skydiver 75 kg 0.7 m^2 60 m/s 134 mi/hr
Baseball (3.66cm radius) 145 gm 42 cm^2 33 m/s 74 mi/hr
Golf ball (2.1 cm radius) 46 gm 14 cm^2 32 m/s 72 mi/hr
Hail stone (0.5 cm radius) .48 gm .79 cm^2 14 m/s 31 mi/hr
Raindrop (0.2 cm radius) .034 gm .13 cm^2 9 m/s 20 mi/hr
Data from Serway, Physics for Scientists and Engineers, Table 6.1.


So we see why the earlier hail stones did not do damage - smaller and less
speedy.

I am not sure what the terminal velocity of the said 5kg block would be.

For golf ball size to be dropping 7,000 metres would take 3 or 4 minutes.
Hail stones usually have to move up and down a few times, electrostatically
driven, to form. The layers in them can be seen.

The greenhouse effect keeps terrestrial heat in the lower layers of the
atmosphere. So the upper atmosphere gets colder. That would produce faster
freezing as well as a larger time to freeze in if something was there to
nucleate the block. Note that colder air will hold less water vapour so
super-saturation would occur more easily and water tend to deposit on any
nucleus already there. But this greenhouse cooling must be happening rather
higher than 7000 metres.

Could be some climatic conditions forming over Auckland owing to some local
conditions. I once saw a thunder/lightning display on the northern side of
Banks Peninsula and it stayed there for half an hour or more, with brilliant
displays of lightning, every third or fourth hitting the sea.

On 21 Jan 2004 20:12:43 GMT, Brian Sandle
wrote:

What is the largest block of ice that can form on a plane?


And where on the airframe does it form? A block of ice of the
magnitude shown on TV would not improve the flying qualities of a wing
.... I assume that any such block could not be formed except near some
outlet on the fuselage or at a junction between the fuselage and a
flying surface.

Brian Harmer wrote:
On 21 Jan 2004 20:12:43 GMT, Brian Sandle
wrote:

What is the largest block of ice that can form on a plane?


And where on the airframe does it form? A block of ice of the
magnitude shown on TV would not improve the flying qualities of a wing
... I assume that any such block could not be formed except near some
outlet on the fuselage or at a junction between the fuselage and a
flying surface.

Yes, well I always wondered whether these meteors should be on the
meteorology newsgroup. Maybe pilots would know know more about it.

Are there any condensation outlets on planes which form 5kg icicles near
them? Maybe some formation flyers would have seen them. When do they drop
off?

I'd file this one right next to "chemtrails".



Brian Sandle wrote:
A several kilogram block of ice fell through the roof of an Auckland house
last evening. Said to be travelling at 450 Km per hour.


Linkname: Scientist says ice meteors a sign of climate change - 10/1/2002
- ENN.com
http://www.enn.com/news/wire-stories.../reu_48569.asp


Scientist says ice meteors a sign of climate change

Tuesday, October 01, 2002
By Emma Ross-Thomas, Reuters
[reuters2.gif]

snip...

Dennis M. Rodgers wrote:
I'd file this one right next to "chemtrails".

In what respect?

Brian Sandle wrote:

A several kilogram block of ice fell through the roof of an Auckland house
last evening. Said to be travelling at 450 Km per hour.


Linkname: Scientist says ice meteors a sign of climate change - 10/1/2002
- ENN.com
http://www.enn.com/news/wire-stories.../reu_48569.asp


Scientist says ice meteors a sign of climate change

Tuesday, October 01, 2002
By Emma Ross-Thomas, Reuters
[reuters2.gif]

MADRID, Spain -- A Spanish scientist says global warming may be to blame
for giant blocks of ice that fall from clear skies and rip gaping holes
in cars and houses.

Jesus Martinez-Frias has spent the last two-and-a-half years
investigating so-called megacryometeors -- ice meteors -- which tend to
weigh more than 22 pounds and have been known to leave five-foot holes in
houses. He fears the formation of these hailstonelike blocks on clear
days could be a worrying symptom of climate change.

"I'm not worried that a block of ice might fall on your head ... but that
great blocks of ice are forming where they shouldn't exist," said
Martinez-Frias, director of planetary geography at Spain's Astrobiology
Center in Madrid. "Components of the atmosphere like ozone and water are
changing in different levels of the atmosphere.... We think these signs
could be evidence of climate change," he said.

While Martinez-Frias said he was far from certain as to why the ice
meteors formed, he said they were neither hoaxes nor blocks of ice
falling from the bars or bathrooms of passing aircraft, as skeptics have
suggested.

"We're not talking about hoaxes," Martinez-Frias said. "It's very easy to
tell real and false ice blocks apart. It's not water from airplane
toilets....

The suggestion I saw was that it fell from a wing, not from a toilet.
The physics involved in a massive block forming in a clear sky through
natural causes is so mind-boggling as to be virtually inconceivable.
Probably ice meteor incidence is correlated with aircraft traffic.

Gib

Gib Bogle wrote:

The suggestion I saw was that it fell from a wing, not from a toilet.

If these large blocks formed on wings they would affect the aerodynamics
wouldn't they?

The physics involved in a massive block forming in a clear sky through
natural causes is so mind-boggling as to be virtually inconceivable.
Probably ice meteor incidence is correlated with aircraft traffic.

A normal tiny meteor can act as a nucleus for ice to form.

Meteors are heated by the heat from the air they compress in front of
them. Some of their surface melts off, but once they get into the denser
atmosphere they can be going rather slow take quite a while to land and
get cooled by the cold air.

There is nothing suspicious about water vapour in clear sky weather. Ever
noticed dew in clear weather? As the air cools in the evening it becomes
able to hold less water vapour. A supersaturated condition forms and water
is deposited on the nearest object available. Quite a lot of dew can be
formed in a few minuters when the dew point is reached. Same thing with
water being heated to 100 degrees Celsius in a smooth vessel. Then if
something rough is put in the steam is allowed to form and it may boil
over.

Where are the data about upper atmosphere temperature and global warming?