Lake Superior changes puzzle scientists

[Aquawind]

http://www.cnn.com/2007/TECH/science/08 ... index.html

Precipitation has tapered off across the upper Great Lakes since the 1970s and is nearly 6 inches below normal in the Superior watershed the past year. Water evaporation rates are up sharply because mild winters have shrunk the winter ice cap -- just as climate change computer models predict for the next half-century.

Yet those models also envision more precipitation as global warming sets in, said Brent Lofgren, a physical scientist with the Great Lakes Environmental Research Laboratory in Ann Arbor. Instead there's drought, suggesting other factors.

Global Warming Models make me gag.. It's worse than talking about the 384hr of the GFS..

Pretty impressive warmup though. Give it a couple more years and they will be "forecasting" hurricane numbers for the Great Lakes.. Residual heat from the 1990's El Ninos? Ummm yea whatever..

[x-y-no]

Global Warming Models make me gag.. It's worse than talking about the 384hr of the GFS..

I don't know about "worse," but it's true that the global climate models still don't inspire much confidence when it comes to regional climate changes. In general, there should be more precipitation - but where it falls is another issue.

[Aquawind]

Global Warming Models make me gag.. It's worse than talking about the 384hr of the GFS..

I don't know about "worse," but it's true that the global climate models still don't inspire much confidence when it comes to regional climate changes. In general, there should be more precipitation - but where it falls is another issue.

Your telling me the GW models predicting weather in years to come are as reliable as a 384hr GFS run? They are that confident in their little box test enviroments of the reactions on a worldwide scale over time? Adding more data makes us more confident when it could just be larger errors?

Sounds like incredible generalizations...way more than even a single GFS run..

[x-y-no]

Your telling me the GW models predicting weather in years to come are as reliable as a 384hr GFS run?

Ummm, no. I would never claim that climate models predict "weather" at all.

My point was that just as the long-range GFS can have an idea of the pattern but be substantially off on the location or amplitude of features, global climate models have a good grasp of the global trend but can still be way off on regional effects.

They are that confident in their little box test enviroments of the reactions on a worldwide scale over time? Adding more data makes us more confident when it could just be larger errors?

Gee ... I would have sworn I said "it's true that the global climate models still don't inspire much confidence when it comes to regional climate changes." Guess I imagined that.

Sounds like incredible generalizations...way more than even a single GFS run..

Whatever.

[Aquawind]

Your telling me the GW models predicting weather in years to come are as reliable as a 384hr GFS run?

Ummm, no. I would never claim that climate models predict "weather" at all.

My point was that just as the long-range GFS can have an idea of the pattern but be substantially off on the location or amplitude of features, global climate models have a good grasp of the global trend but can still be way off on regional effects.

They are that confident in their little box test enviroments of the reactions on a worldwide scale over time? Adding more data makes us more confident when it could just be larger errors?

Gee ... I would have sworn I said "it's true that the global climate models still don't inspire much confidence when it comes to regional climate changes." Guess I imagined that.

Sounds like incredible generalizations...way more than even a single GFS run..

Whatever.

Nice Tone..

I still don't see how climate models can be as credible or accurate as the GFS on any scale.

[x-y-no]

Nice Tone..

You set the tone from the very beginning ("Global Warming Models make me gag.. It's worse than talking about the 384hr of the GFS.. ") and continued it in your first reply. I don't think you have any call to complain if you get a little of your own medicine.

I still don't see how climate models can be as credible or accurate as the GFS on any scale.

They've done a fine job on the latest decade (the observed warming trend is right smack in the middle of the predictions published in the IPCC Second assessment review in 1995) and also do a fine job of hindcasting the past.

[Aquawind]

Read again.. I didn't direct anything other than questions to you and yes I do think the resolution is so weak it's a generalization.

[x-y-no]

I see ... questions can't have a tone?

Read again yourself. You're fairly dripping contempt throughout this thread.

[Aquawind]

That's baloney.. I was surprised at your response and had some questions for clarification..

[x-y-no]

OK, obviously we're not going to see eye to eye on tone.

Getting back to the original discussion:

There's a pretty decent discussion of why GCMs don't perform well on the regional level despite good performance on a global level here.

And Chpter 8 of the IPCC WG1 AR4 (pdf document) is all about the evaluation of the performance of the GCMs.

[Aquawind]

No.. It's actually not OK. Your continued Anthropogenic GW agenda drive to dicredit others posts in this forum is pretty clear. I have no idea what the heck your thinking trying to read into my clear simple questions with such a rude response. Well I do but no need to go there.. No wonder this forum hasn't grown more. I doubt it will with responses like that.

[x-y-no]

All right ... I tried to be diplomatic and get this conversation back on track, but you're dead set on a fight.

So ...

You wrote:

Global Warming Models make me gag.

Not exactly a temperate remark.


Then in response to my comment, you wrote:

Your telling me

followed up by a statement that bore absolutely no relation to anything I would ever say. If you don't see that as setting an adversarial tone, then I don't know what to think.


Then you wrote:

They are that confident in their little box test enviroments of the reactions on a worldwide scale over time? Adding more data makes us more confident when it could just be larger errors?

when I had just stated (and the researchers in the field don't deny) that there is not great confidence in the performance of GCMs on regional climate.

Again, a truculent comment without any backup and clearly designed to do nothing but start an argument.



So, whatever. Despite all that, you're the innocent lamb and I'm the big bad global warming bully. But I'll note that I'm offering some substance to back up what I say, whilst you're only dishing out aggrieved opinion. I know I shouldn't allow myself to be irritated by all this, but what can I say? I'm human.

[Regit]

No.. It's actually not OK. Your continued Anthropogenic GW agenda drive to dicredit others posts in this forum is pretty clear. I have no idea what the heck your thinking trying to read into my clear simple questions with such a rude response. Well I do but no need to go there.. No wonder this forum hasn't grown more. I doubt it will with responses like that.

Sorry, I had to chime in on this.

The reason Jan likes to argue the points on here is because he's equipped with a wealth of knowledge on the subject.

Jan's knowledge of climate change is extensive and provides the ability to be able to engage anyone on the subject. The problem is he's often faced with people who don't have anywhere close to that amount of knowledge, so it may come across as an agenda when it's simply a concise, effective dismantling of the opposing argument.

If you can match his knowledge step by step and counter his arguments, please offer it. Intelligent arguments work much better than ad hominem attacks.

[Aquawind]

Once again your reading into this as if it's directed at you and yet made it a personal attack.. Beleive what you want clearly you think you know it all related to this subject and anything even in question is a slam dunk answer for you. Of course you enter your link to a report from the IPCC and you have given sustance, but of course my link is not substance and my opinion is worthless. I will have to let you swim in your moat here at storm2k..

Intelligent arguments work much better than ad hominem attacks.

Nice..another indirect insult. No need to be sorry I am not a pathetic as you both may think..

[x-y-no]

Once again your reading into this as if it's directed at you and yet made it a personal attack..

Well the combative "Your telling me [stuff I would never say]" sure seemed like a personal attack ... and given:

Beleive what you want clearly you think you know it all related to this subject and anything even in question is a slam dunk answer for you.

it sure as heck looks like an ongoing one. I've never claimed I "know it all" or that everything "is a slam dunk answer." Far from it. Over the years I've discussed many things that are interesting open questions and also discussed the level of uncertainty of many aspects of the field.

Of course you enter your link to a report from the IPCC and you have given sustance, but of course my link is not substance and my opinion is worthless.

I never said the original link isn't substance. And in fact I've said absolutely nothing that contradicts the substance of that link. In fact, my very first comment in this thread agreed that the GCMs are not yet particularly good at regional climate effects.

But that first link of yours isn't any kind of backup for your absolute dismissal of climate models.

By contrast, the links I provided give backup to the argument I'm making. The first link I provided was a discussion of how GCMs can be good at global average climate but bad at specific regional climate. The second (IPCC) link is an extensive discussion of exactly how GCMs have been evaluated and why that evaluation indicates good reliability on the global scale.

I will have to let you swim in your moat here at storm2k..

Whatever. It sure seems to me that this outcome was your intent from the beginning.

[Aquawind]

omg.. whatever.

[CajunMama]

How did this get to this? From my point of view of the first 2 posts in here you both were agreeing that gw aren't worth much.

[x-y-no]

How did this get to this? From my point of view of the first 2 posts in here you both were agreeing that gw aren't worth much.

No, I wasn't agreeing to that. What I do agree about (and what the article originally posted indicates) is that the general circulation models used to predict future climate are not yet particularly good at resolving regional climate effects. Aquawind (as near as I can tell) thinks GCMs are totally worthless.

[CajunMama]

oops...i left out a word!

*gw models aren't worth much* (proofread, CM, proofread!)

[x-y-no]

oops...i left out a word!

*gw models aren't worth much* (proofread, CM, proofread!)

Well, I wouldn't agree with that either. The important word, from the point of view of my discussion above, is "regional." GCMs perform very well on the global scale. What they don't do well yet is resolve regional climate.