Comments on: "Explaining" a Positive NAO

By: Kenneth Fritsch

Kenneth Fritsch — Sun, 19 Apr 2009 16:45:33 +0000

Re: Micky C (MC) (#28), Mickey, you definitely describe a frustration I have with the current treatment of the MWP/MCA. With the evidence presented it seems to remain rather fuzzy - until a summary comment is made where the term MCA is used along with all that that term implies. Re: Craig Loehle (#27), Craig, please continue bringing on the science and we will interpret the spelling.

By: Andrew

Andrew — Sun, 19 Apr 2009 14:28:21 +0000

Re: Micky C (MC) (#28), I know what Occams Razor is. I just didn't get what you thought needed cutting away. Thanks for clarifying.

By: Micky C (MC)

Micky C (MC) — Sun, 19 Apr 2009 13:35:23 +0000

Re: Andrew (#26), It's quite a normal acitivity in building a theory. You can't have it both ways. Either there is or was a complex process that lead to the MWP that is not detectable today, and this is superseded by the CO2 forcing model, or the interaction is still taking place and that this has a hand in actually driving current temps. Or there never was a complex interaction and CO2 caused the MWP. If you start with a theory you must apply it to all situations; the more it gets convoluted and 'special circumstances' appear, then you cut the theory. Occams Razor: Cut away the more improbable and over-complicated explanations. The subtle point is that the theory can be complex but universally complex; it doesn't have to be a simple linear cause and effect type theory. THis MWP/MCA explanation is interesting and by logic it must apply today. So where does that leave the other forcing model?

By: Craig Loehle

Craig Loehle — Sun, 19 Apr 2009 01:26:24 +0000

Re: Kenneth Fritsch (#25), I studied the sciences, no spelling classes either.

By: Andrew

Andrew — Sat, 18 Apr 2009 23:04:23 +0000

Re: Kenneth Fritsch (#25), Craig is speaking with a sophisticat' univuhsity graduate! But now adays I reckon they teach you how to arm wave, not identify it. But hey, its...education. Re: Micky C (MC) (#23), Um, what exactly are you proposing needs Razoring? I don't quite understand what you are saying.

By: Kenneth Fritsch

Kenneth Fritsch — Sat, 18 Apr 2009 22:34:08 +0000

Re: Craig Loehle (#24),

I feel really deprived–there was no course in arm-waving at my univesity…

I thought universities taught identification of arm waving - and spelling.

By: Craig Loehle

Craig Loehle — Sat, 18 Apr 2009 21:52:59 +0000

Re: TAG (#17), I feel really deprived--there was no course in arm-waving at my univesity...

By: Micky C (MC)

Micky C (MC) — Sat, 18 Apr 2009 16:57:51 +0000

Though Trouet and Gray may be correct there is a more pressing concern. On one hand the appearance of an MWP/MCA is explained by a complex interaction of thermohaline and North Atlantic Oscillations, where as with regards to today these interactions are superseded by a simple “increase in CO2 causes increase in forcings” relationship and temp goes up. So unless they can explain the context of both types of behaviours with regards to universality, at least one of them is not correct. Sounds like a philosophical argument hence Occams Razor time.

By: Ian

Ian — Sat, 18 Apr 2009 06:33:49 +0000

Interesting new article considering AMO and Sub-Saharan Africa in this context BBC summary UA Version Sorry no link to Reader's Digest Science article, I don't go there anymore for scientific info

By: David Smith

David Smith — Sat, 18 Apr 2009 03:51:24 +0000

Latif's conjecture on a Pacific/Atlantic connection can be found here . It also speculates on how a strong THC eventually leads to a weakened NAO. There is also a relationship between NAO strength and Arctic ice (high winter NAO values tend to flush ice out of the Arctic, I believe). If that is correct then Latif's Figure 4 may benefit Arctic ice cover in the coming decades.