From
http://www.bbc.co.uk/sn/tvradio/prog..._summary.shtml

In the Andes mountains, climate researcher Dr Lonnie Thompson, of Ohio
State University, was gathering evidence of the region's climatic
history using ice cores drilled in glaciers.

Almost immediately Thompson and his team noticed something intriguing.
The historic records showed that over the last one hundred years, every
time the ice cores showed drought in the mountains, it corresponded to
a particular kind of wet weather on the coast, a weather system known
as an El Nino. In other words drought in the mountains meant an El Nino
on the coast. If Thompson could trace back the climate record in the
mountains he'd also get a picture of what happened on the coast.

The result was fascinating. The climate record suggested that at around
560 to 650 AD - the time the Moche were thought to have collapsed -
there had been a 30-year drought in the mountains, followed by 30 years
or so of heavy rain and snow.

If the weather on the coast was the opposite, then it suggested a
30-year El Nino - what climatologists call a mega El Nino - starting
at around 560 AD, which was followed by a mega drought lasting another
30 years. Such a huge series of climatic extremes would have been
enough to kill off an civilization - even a modern one.

Then Steve Bourget found evidence of enormous rain damage at a Moche
site called Huancaco which he could date. Here new building work had
been interrupted and torn apart by torrential rain, and artefacts found
in the damaged area dated to almost exactly the period Thompson had
predicted there would have been a mega El Nino. Thompson's theory
seemed to be stacking up.

Then archaeologists began to find evidence of Thompson's mega drought.
They found huge sand dunes which appeared to have drifted in and
engulfed a number of Moche settlements around 600 to 650 AD.

*******

So what caused the events reported? The programme was too busy
detailing a theory about a so called vanished culture to get into
anything seriously useful.

Weatherlawyer wrote:
From
http://www.bbc.co.uk/sn/tvradio/prog..._summary.shtml

In the Andes mountains, climate researcher Dr Lonnie Thompson, of Ohio
State University, was gathering evidence of the region's climatic
history using ice cores drilled in glaciers.

Almost immediately Thompson and his team noticed something intriguing.
The historic records showed that over the last one hundred years, every
time the ice cores showed drought in the mountains, it corresponded to
a particular kind of wet weather on the coast, a weather system known
as an El Nino. In other words drought in the mountains meant an El Nino
on the coast. If Thompson could trace back the climate record in the
mountains he'd also get a picture of what happened on the coast.

The result was fascinating. The climate record suggested that at around
560 to 650 AD - the time the Moche were thought to have collapsed -
there had been a 30-year drought in the mountains, followed by 30 years
or so of heavy rain and snow.

If the weather on the coast was the opposite, then it suggested a
30-year El Nino - what climatologists call a mega El Nino - starting
at around 560 AD, which was followed by a mega drought lasting another
30 years. Such a huge series of climatic extremes would have been
enough to kill off an civilization - even a modern one.

Then Steve Bourget found evidence of enormous rain damage at a Moche
site called Huancaco which he could date. Here new building work had
been interrupted and torn apart by torrential rain, and artefacts found
in the damaged area dated to almost exactly the period Thompson had
predicted there would have been a mega El Nino. Thompson's theory
seemed to be stacking up.

Then archaeologists began to find evidence of Thompson's mega drought.
They found huge sand dunes which appeared to have drifted in and
engulfed a number of Moche settlements around 600 to 650 AD.

*******

So what caused the events reported? The programme was too busy
detailing a theory about a so called vanished culture to get into
anything seriously useful.

Brian Fagan discusses the Moche civilization in his 1999 book
_Floods, Famines and Emperors: El Nino and the Fate of
Civilizations_, chapter 7. The book _El Nino in History_ by
Caviedes also touches on it, but IMO this isn't as good a book.
Around 540 AD and for a couple of decades after, tree rings
in a number of places across the world suggest extreme short
term climate anomalies according to the book _Exodus to
Arthur_ by Mile Baillie. The cause is unclear, but the author
advances some hypotheses. I don't recall him linking these
to enhanced/prolonged ENSO activity, but there might be
a connection. Anyway, it is all fascinating stuff, IMO.

Cheers,
Russell

wrote:
Weatherlawyer wrote:

So what caused the events reported? The programme was too busy
detailing a theory about a so called vanished culture to get into
anything seriously useful.

Brian Fagan discusses the Moche civilization in his 1999 book
_Floods, Famines and Emperors: El Nino and the Fate of
Civilizations_, chapter 7. The book _El Nino in History_ by
Caviedes also touches on it, but IMO this isn't as good a book.
Around 540 AD and for a couple of decades after, tree rings
in a number of places across the world suggest extreme short
term climate anomalies according to the book _Exodus to
Arthur_ by Mile Baillie. The cause is unclear, but the author
advances some hypotheses. I don't recall him linking these
to enhanced/prolonged ENSO activity, but there might be
a connection. Anyway, it is all fascinating stuff, IMO.

I was more interested in the climate detail than the huge jumps in
conlusions about a vanished governmental system. There is a link to the
el nino data collection in the site above: Punctuated equilibrium:
Searching the Ancient Record for El Nino. In The Quarterly Review of
Archaeology vol 8, no.3, 1987 by Michael Moseley

On a recent thead here I was proposing that most major cyclical upsets
are caused by deforestation, a more likely alternative to global
warming in my not very humble opinion.

Another link on the BBC site shows a detail of the weather system for
the Andes from the Pacific
http://www.bbc.co.uk/nature/programm.../virtual.shtml

The Amazon basin resembles a fan like leaf whose edge is the Andes and
whose stalk is the Amazon. Whilst all the water drains from the Andes
in the west to the Atlantic in the east, the wind system is blowing
rain clouds the other way.

A lot more on he http://www.bbc.co.uk/sn/tvradio/programmes/amazon/

I'm not that interested in fraught conclusions about things that can't
be changed. Especially not politics. It would seem that the culture
never changed that much and there is no history of human sacrifice in
what appears to be a friendly region o/a, despite outward apearances.

The programme alluded to human sacrifice but the evidence is more
suggestive of people starving doing things they would pay for later.
However if the riddle about what caused the problems is to be resolved,
I suppose a deal of anthropology is required.

Suppose the various tribes got to America once the Babylonian Empire
was replaced. Would it be possible that they were the slaves once
specialists in canal and pyramid building, looking for an home?

Which would put the colonising of the continent (or at least a boost to
it) some 1000 years prior to the demise of the Moche. Just enough time
to turn the plains of the Amazon into a jungle. So why settle in a
desert?

All pointless speculation. But it does seem that the majority of the
artisans that settled in South America settled on the west coast.

Weatherlawyer wrote:

From
http://www.bbc.co.uk/sn/tvradio/prog..._summary.shtml

In the Andes mountains, climate researcher Dr Lonnie Thompson, of Ohio
State University, was gathering evidence of the region's climatic
history using ice cores drilled in glaciers.

Almost immediately Thompson and his team noticed something intriguing.
The historic records showed that over the last one hundred years, every
time the ice cores showed drought in the mountains, it corresponded to
a particular kind of wet weather on the coast, a weather system known
as an El Nino. In other words drought in the mountains meant an El Nino
on the coast. If Thompson could trace back the climate record in the
mountains he'd also get a picture of what happened on the coast.

The result was fascinating. The climate record suggested that at around
560 to 650 AD - the time the Moche were thought to have collapsed -
there had been a 30-year drought in the mountains, followed by 30 years
or so of heavy rain and snow.

I've just been watching a plausible story about the last ice age; a
recording from the Open University on the BBC's educational, night time
filler. There seems to be a massive fault in the interpretation in what
glaciers can and can't do. But I'm fuzzy on what that is exactly.
Pointless of me trying to take the argument apart without knowing at
leat something about glaciers.

The problem has a focus somewhere in the way that experts were
presenting facts: Look over here and we see evidence that the glacier
deposited this and that sort of thing. They never say how, because the
physics of such large ice sheets is still cutting edge physics.

So, one more cross post.

We know that ice is transparent to most forms of sunlight. And it would
appear that there is a tendency for it to become colder than diurnal
variations of insolation would allow mainly because of reflection and
refraction near the surface.

So that's why alpine glaciers can exist. They can even exist at lower
latitudes even where the ice is out near the regions where the
atmosphere is thin.

In fact for some reason the ice can last indefinitely in the Andes of
northern Peru.

All of Peru is in the tropics. Northern Peru reaches almost to the
Equator and the centre of Peru is some 10 degrees south. It gets most
of its sunlight at acute angles. Why are they so cold? Despite having
24/7 sunlight in summer, most people insist it is the angle of the sun
that keeps the polar ice extant.

Anyone got any links on the physics of ice? Mechanical stuff please not
religious or quasi religious scientific beliefs.

Weatherlawyer wrote:

Here is a thread that will close out this empty specuation:
Which would put the colonising of the continent (or at least a boost to
it) some 1000 years prior to the demise of the Moche. Just enough time
to turn the plains of the Amazon into a jungle. So why settle in a
desert?

All pointless speculation. But it does seem that the majority of the
artisans that settled in South America settled on the west coast:

http://groups.google.co.uk/group/alt...32c4948d896f/?

Perhaps.

I was looking fro a source of the dust in an earlier thread but I just
couldn't see how, if the cultures that farmed the Amazon basin got
there in biblical chronological order, would have moved to destroy it.

Whilst a lot of former slaves in the Sumarian empires would have been
made freemen with the rise of the Medes and spurred a move to a world
wide diaspora. It's hard to see a mass deforestation so late in the
settlement. The only conclusion I could jump to was the vast
plantations had some catastrophic event when they reached a critical
point.

Yes I know it was a daft idea. What other ones were there before this
mass transportation was pointed out?

in article ,
Weatherlawyer at wrote on 3/12/06 3:59 AM:


Weatherlawyer wrote:

From
http://www.bbc.co.uk/sn/tvradio/prog..._summary.shtml

In the Andes mountains, climate researcher Dr Lonnie Thompson, of Ohio
State University, was gathering evidence of the region's climatic
history using ice cores drilled in glaciers.

Almost immediately Thompson and his team noticed something intriguing.
The historic records showed that over the last one hundred years, every
time the ice cores showed drought in the mountains, it corresponded to
a particular kind of wet weather on the coast, a weather system known
as an El Nino. In other words drought in the mountains meant an El Nino
on the coast. If Thompson could trace back the climate record in the
mountains he'd also get a picture of what happened on the coast.

The result was fascinating. The climate record suggested that at around
560 to 650 AD - the time the Moche were thought to have collapsed -
there had been a 30-year drought in the mountains, followed by 30 years
or so of heavy rain and snow.

I've just been watching a plausible story about the last ice age; a
recording from the Open University on the BBC's educational, night time
filler. There seems to be a massive fault in the interpretation in what
glaciers can and can't do. But I'm fuzzy on what that is exactly.
Pointless of me trying to take the argument apart without knowing at
leat something about glaciers.

The problem has a focus somewhere in the way that experts were
presenting facts: Look over here and we see evidence that the glacier
deposited this and that sort of thing. They never say how, because the
physics of such large ice sheets is still cutting edge physics.

So, one more cross post.

We know that ice is transparent to most forms of sunlight. And it would
appear that there is a tendency for it to become colder than diurnal
variations of insolation would allow mainly because of reflection and
refraction near the surface.

So that's why alpine glaciers can exist. They can even exist at lower
latitudes even where the ice is out near the regions where the
atmosphere is thin.

In fact for some reason the ice can last indefinitely in the Andes of
northern Peru.

All of Peru is in the tropics. Northern Peru reaches almost to the
Equator and the centre of Peru is some 10 degrees south. It gets most
of its sunlight at acute angles. Why are they so cold? Despite having
24/7 sunlight in summer, most people insist it is the angle of the sun
that keeps the polar ice extant.

Anyone got any links on the physics of ice? Mechanical stuff please not
religious or quasi religious scientific beliefs.


http://www.natice.noaa.gov

may be a good starting point.

Matthew Lybanon wrote:

http://www.natice.noaa.gov may be a good starting point.

Could well be. They are entering the millenium at last I see: Netscape
or Mozilla Users (Please Enter here)

Thanks for the link. I'll just brush up with the Encyclopædia
Britannica, then plunge in.