Archaeologica.org

It wasn't a meteorite impact that caused the dino's extinction, according to British researchers. Nor the Deccan Traps event. They posit it was a series of radical environmental change events that started 135 mya with a sudden global 9 degree (centigrade) temperature drop:

http://www.telegraph.co.uk/science/dino ... claim.html

But why temperatures would have dropped so suddenly isn't made clear:

The drop in temperature is thought to have occurred because high levels of CO2 were in the atmosphere which caused global temperatures to rise and polar ice to melt – a phenomenon currently predicted for Earth.

I don't see (yet) how rising levels of CO2 (= green house climate = rising temperatures) would have caused a sudden drop in temperatures. That doesn't seem to make sense.

The suggestion is RS that the increased fresh water entering the north Atlantic would divert the Gulf stream south. One question though, was there a Gulf Stream 135 mya?

Roy.

Probably not, if you play around with this animation.

http://www.google.com/imgres?imgurl=htt ... CBQQ9QEwAw



Click on Contintental Drift Animation and turn "Labels" to On.

Well as far as I can tell from that Min the Panamanian Isthmus was open, which would imply that there was no Gulf flow.
The argument that melt water would result in an ice age was from our Meteorological Office AFAIK, and I wouldn't trust them to get the day of the week correct!
This is the same mob that used their computers to 'model' the ash cloud from the Icelandic volcano, now most logical people would have measured the particle density, but not them.
We can't even find out what practical measures were used to produce their model, and these are the same guys who originally claimed that melting polar ice would stop the Gulf flow.
They've recently received a bonus!
One of the Europe's aviation authority's sampling aircraft is a micro light! A sample collector on top of a tall building would probably do the job as well IMO!

Roy.

and I wouldn't trust them to get the day of the week correct!

Don't hold back, Dig. Tell us how you really feel!

Digit wrote:We can't even find out what practical measures were used to produce their model, and these are the same guys who originally claimed that melting polar ice would stop the Gulf flow.

So no equivalent of a Freedom of Information Act over there?

Don't hold back, Dig. Tell us how you really feel

I daren't!
Yes we do Dan, but it has quite a few get outs. The Met Office has recently been in trouble for refusing requests for info, they have even tried to classify their climate model as a state secret!
At the moment they are getting it in the neck over their lack of expertise on the ash alarm.

http://www.telegraph.co.uk/comment/colu ... f-ash.html

You couldn't make it up!

Roy.

Digit wrote:The suggestion is RS that the increased fresh water entering the north Atlantic would divert the Gulf stream south. One question though, was there a Gulf Stream 135 mya?

No, there wasn't: Pangea was just separating into the Old and the New world, so there wasn't an Atlantic Ocean yet. It was just a strip, a widening gap. Also south America and north America weren't joined at Panama (that only happened 4 mya), so there wasn't a Caribean basin that was 'closed' on 3 sides as there is now. There was a 4,000 mile gap/open connection with the Pacific Ocean where Panama/Honduras/Costa Rica, etc., are today. So a 'warm' Gulf stream could not exist.

And without a Gulf stream the 'conveyor belt' (a.k.a. Themohaline Circulation) oceanic water transport system (our global airconditioning system) would have been vastly different. Ergo, climates, and their distribution, were vastly different (e.g. Antarctica was tropical!).

Quite Rs. And it's a fact that most people don't seem to realise the effect that geography has on currents, climate etc. I wonder what would happen if the Panama isthmus sank?

Roy.

Digit wrote:I wonder what would happen if the Panama isthmus sank?

Which isn't at all unthinkable looking at the increased (ramping up?) tectonic/volcanic activity in the last few years.

It would certainly make things a lot more chilly in our latitudes!

It would certainly make things a lot more chilly in our latitudes!

Logic would support that RS, but what effect would it have, if any, on the Pacific currents?
Equally well if Florida joined south America the Gulf would become a shallow fresh water lake, it's a threadbare margin by which we have what we have is it not?

Roy.

Yes, it is.

Digit wrote:

It would certainly make things a lot more chilly in our latitudes!

Logic would support that RS, but what effect would it have, if any, on the Pacific currents?
Equally well if Florida joined south America the Gulf would become a shallow fresh water lake

If you're really interested: get a research grant, purchase supercomputer time, and build and run a model. it's only a giga spreadsheet cum ginormous database. Should be perfectly doable, though.

According to some critics the only way to get a grant is to tie the research into GW!

Roy.

That shouldn't be too hard if you were really motivated.