2010-10-23 10:18:44Updated=Response to Wu et al. 2010
Robert Way

robert_way19@hotmail...
134.153.163.105

This is now the intermediate rebuttal for Ice Sheet Losses are Overestimated

You can find it

here

Let me know what you think.

Robert Way

2010-10-23 11:03:17Comment
Robert Way

robert_way19@hotmail...
134.153.163.105
Another thing I think is interesting is this below

http://www.skepticalscience.com/pics/WuetalComparison.png

The image shows on the left the icesat direct elevation change measurements and on the right Wu et al's interpretation of Greenland Mass changes.

Seems odd that the direct measurements of changes in elevation from laser altimetry are not picking up this massive gain in the interior. I've heard of interior areas gaining in Greenland sure but the gains shown by Wu et al are pretty big to be missed by all four icesat methods...

and pritchard et al. 2009

http://www.skepticalscience.com/pics/Pritchardetal2009.png
2010-10-23 14:46:29Good to add some context
John Cook

john@skepticalscience...
124.186.160.198
The list of all the different methods that find higher ice loss is to me the most powerful part of the post - that's the take-home for me from this post. When you say "Greenland experienced the highest recorded melt rate since monitoring began in 1958", was this is 2010? It would clarify if you specify the period here. I found that pic of ice melt from the 2010 Arctic report card a powerful visual, perhaps include that or throw in a few graphics in there somewhere to break up the text. Lastly, perhaps a vatchier headline. Graham, you're the clever headline writer...
2010-10-23 18:32:00
Rob Painting
Rob
paintingskeri@vodafone.co...
118.93.215.69
Great work, Rob. Very informative. Graphs?.
2010-10-23 19:40:16
Riccardo

riccardoreitano@tiscali...
93.147.82.78

I think you should leave the conclusion open. I agree with John that, as usual, many different techniques give a stronger evidence than just one, even if it's the best/more accurate/more recent. You did a great job in showing what we know and that never a single paper is to be taken as the last word; you've also been correct in not saying that Wu et al. is garbage but simply that we have no reason to believe that it's "the best". But I'm afraid that your last claim might (will?) be turned into "he's dismissing the paper".

This was after a first and quick reading, maybe I will be back later.

2010-10-27 15:03:33Comment
Robert Way

robert_way19@hotmail...
134.153.163.105
I will take a look at this and maybe change the tone but I have to be honest by saying the more and more I look at the evidence, the more I feel that their conclusions are wrong. And I hate to say that because i'm not disproving them in the scientific literature as per the accepted scientific methodology but here's a summary of what I think (i'm not going to write this but I don't have as much a problem as you with concluding that their results are not supported by current evidence, that being said, I wouldn't wanna be dismissive)

<> They are using the noisiest data to extract an ice loss signal so there's always initial error bars
<> They tried to make a solution for Greenland based upon 3 GPS sites across Greenland
<> They found strong agreement with low resolution radar altimetry studies (Shown to be inaccurate in Thomas et al. 2008, its why cryosat-2 is a much higher resolution)
<> The pattern of their ice losses and gains does not match the patterns from work that uses pure elevation differencing.
<> They find incredible growth in the interior of Greenland where RAW laser altimetry has found very little growth (less than 0.5 m a year) (Pritchard et al. 2009)
<> They find incredible growth where Sorensen et al. 2010 find no incredible growth even using 4 different methods (with diagrams that support my hypothesis)
<> Their results disagree with previous Grace studies, previous laser altimatry studies, previous radar interferometry studies and previous surface mass balance studies
<> Bamber et al. 2010 chose to go with another studies estimates because of how preliminary the results are considered
He wrote THE book on how to measure ice sheet mass balance changes and is incredibly well respected. He's kinda in a class of his own amongst his peers.

My feeling personally is that between 160 and 240 GT a year is the consensus and probably around 200 which means more than 0.5 mm/yr to sea level rise


Any thoughts on how I should address this argument?

2010-10-27 20:40:54
Riccardo

riccardoreitano@tiscali...
192.84.150.209

 Robert,

I was making something more of a general statemt than a specific issue with your conclusions. Unless there's something clearly wrong in a peer reviewed paper, we should use somewthing less strong than "it is".

For example, you wrote "is not the best representation ...". "Is not" is a definitive statement and gives the impression that you're trying to close the discussion on Greenland ice loss.. "Probably is not" sends the same message (the paper is not convincing)  but gives a much different impression on your attitude.

Anyways, I agree that it is not the best representation of the trends in Greenland ice loss :)

2010-10-27 23:32:58comment
Robert Way

robert_way19@hotmail...
134.153.3.144
Okay Riccardo,
I see what you're getting at here. It's not necessarily about what is being said but rather the definitiveness of how its being said. I fully understand that and will make changes to improve. Thank you for your input.
2010-11-11 08:58:56Robert- Updated
Robert Way

robert_way19@hotmail...
134.153.163.105
Updated See 1st post
2010-11-11 10:44:04Thumbs up
John Cook

john@skepticalscience...
124.186.160.198

Great article, Robert, meticulous work.

You did ask Dr Ivins for permission to publish his email, right?

A big point from this post is that even Wu is at the upper range of IPCC predictions. I'm willing to bet no skeptic is aware of that, particularly the ones who cite Wu as evidence in their favour. You know, I've seen comparisions of IPCC predictions of sea level rise to observations - but I've never seen a similar comparison with ice loss from Greenland or Antarctica. Now that would be an interesting graph.

2010-11-11 10:45:55Thumb
John Cook

john@skepticalscience...
124.186.160.198
Forgot, here's the thumb
2010-11-11 11:55:50comment
Robert Way

robert_way19@hotmail...
142.162.11.6
Actually i didn't ask Dr. Ivins,

I should send him an email and make sure its okay. Mind you he did forward his email he sent me to 4 other people but I understand what you mean. How should I go about that?
2010-11-11 13:37:22Just say you write for Skeptical Science, maybe give him an excerpt of what you plan to publish
John Cook

john@skepticalscience...
124.186.160.198
Definitely ask him before you publish this. I quoted a scientist from some private correspondance once, without asking permission, and he went ballistic. I remember getting his email where he angrily said "never contact me again" and the blood drained from my face in horror. I rushed to remove the quote from the website immediately and sent a reply profusely apologising. It did smooth things over, he said he overreacted but I learnt a valuable lesson - always, ALWAYS ask for permission before publishing private correspondance.
2010-11-11 16:49:07
Rob Painting
Rob
paintingskeri@vodafone.co...
118.92.80.23
John, excuse me but what a dufus that scientist is. I understand him being pissed off, but that's a little over the top. 
2010-11-12 05:43:11
Ari Jokimäki

arijmaki@yahoo...
91.154.99.160
Looks good.
2010-11-12 08:47:33
Riccardo

riccardoreitano@tiscali...
93.147.82.182
Thumb up
2010-11-12 11:16:47Thanks
Robert Way

robert_way19@hotmail...
134.153.163.105
Thanks, I've updated it a little bit just to make the wording a little cleaner in some cases.

I think that i'm just waiting on Ivins go ahead (for letting him be quoted) at this point but i'd still like any revisions (especially in wording) that people are willing to offer up.

Robert Way


<<>>>>>> John,
half the text disappeared when  I tried editing it and i've had a hell of a time getting it back. Every time I paste it in and click "save" it doesn't seem to work. It doesn't save.

Ive changed it to an advanced rebuttal and it works now...

here
2010-11-12 22:43:44Missing text
John Cook

john@skepticalscience...
124.186.160.198
You're not going to like what I'm going to say but I think the missing text is gone. It's happened to me a few times, some glitch with the wysiwyg editor but whenever it happened, I noticed it before I saved my changes and reloaded the webpage. This would restore the content to how it was before the text went missing. By saving it, that earlier text was written over :-(

but if you have a copy saved elsewhere and you can't put it back in, perhaps just email it to me and I'll paste it in for you. Sometimes when the wysiwyg editor fails you, you just have to work with the raw code but that requires a familiarity with HTML.

2010-11-13 02:50:20Comment
Robert Way

robert_way19@hotmail...
134.153.163.105
The text is still there under the advanced version, so that is the one that will have to be published. I hope ivins responds soon... Personally I don't think it will be a problem because I did say this in the email to him

"... I was interested on doing a post on skepticalscience about the subject but I thought I would email an author of the paper (I knew of your previous work) to see what your opinion is and perhaps to see what your thoughts on the certainty of the paper are."