Thursday, January 16, 2014

Nathan Drake vs., Steve McIntyre on the Spirit of Mawson Matter

Now Eli is not one to interfere with a good pasting, but it looks like Nathan Drake is putting it to Steve McIntyre over at the Nature Blog. Eli has to go to a meeting but, as Drake points out McIntyre has made a major mistake in  using MODIS visible images to track ice.  Basically, visible images are not much use for bad weather situations, and microwave is a much better choice.  There is more over there.  FWIW Shrub is losing a few spare eyeballs.


Anonymous said...

Eli, you should reflexively defer to the superior intellect - Steve McI. Bad rabbit.

William M. Connolley said...

I don't think using visible is a mistake, let alone a major one. You get much higher rez than you do from microwave.

What's missing is the meteorology.

Wouldn't it be nice if NS and McI could talk without rehashing the hockey stick wars in the first para of every comment?

Anonymous said...

William Connolley said.
"I don't think using visible is a mistake, let alone a major one. You get much higher rez than you do from microwave"

Good. do you mind telling us how you would go about separating clouds from ice?
i.e. how would you respond to:
"For a robust qualitative assessment you would need to assign classes of sea ice based on a unique spectral signature range. This is normally done through any of several spectral classification schemes, for a quick and dirty analysis most would use a manual classification if they had prior knowledge of the spectral characteristics of the target feature.That classification would then be applied to the time series of imagery, and a qualitative analysis could be carried out based on the spatio-temporal dispersion of spectral classes. That is the simplest robust method of qualitative analysis of MODIS visible data, a truly robust analysis would involve in-situ calibration on the sea ice with a portable radiometer and a significant training data set to ensure both accurate and precise results"


Anonymous said...


you might want to look at the piccys before asking:

EliRabett said...

the problem, dearest anon, is that as Drake points out the MODIS pictures are meaningless. Crayons.

Susan Anderson said...

The enemy of my enemy is my friend. Idiots delight when wrong prevails.


Why debate the hyperspectral issues when the captan on the bridge has the real time wind field at his command :,-89.02,244

William M. Connolley said...

Um. You do realise that you'll all talking about something you know nothing about, relying entirely on the word of someone you've never heard of, but who happens to be saying something you want to hear?

I can go to WUWT if I want to read people doing that. They do it better because they've had more practice.

> you might want to look at the piccy

I did that before the Nature piece was published. See "Yet another update" at McI's imagery composite is useful, if flawed.

> for a robust qualitative assessment you would need to assign classes of sea ice based
> MODIS pictures are meaningless

These are just stupid. You're not playing some silly game in which you artificially restrict yourself to one data source and try to guess as much as possible from that.

You use all the data available and do your best. The microwave stuff is useful, sees through clouds, but isn't very detailed. Adding the viz imagery on top helps add detail.

William M. Connolley said...

> something you know nothing about

Meh. I make it sound like I'm an old hand at forecasting Antarctic sea ice. But I've never done it. I've modelled it, but that's very different.

I have sat in the same room while our (BAS; the "our" dies hard) Met people pored over charts trying to see if one of our ships could make it through the ice to Halley. And its really difficult to work out the ice conditions (that included some radar imagery, which wasn't then routinely available, you had to ask for it, I don't know now). So I should make it clear that I'm *not* trying to claim that if only CT had looked at Modis, all would be well. Indeed its plain from what McI says that CT says, that CT did indeed look at Modis at some point (which makes it hard to understand those now saying Modis is useless).

The main thing missing from all this discussion is the meteorology, and the use of forecasts. Sea ice isn't really created or destroyed on these timescales, only advected. So you care a lot about the winds.

Bernard J. said...

It appears that there are two grades of self-righteous high dudgeon at work in this matter - the drones who adhere to the "Antarctic sea ice, therefore no global warming!!!1!!eleventy one!" canard, and those partial to scarecrow erections, who peddle the "scientists and tourists should never mix, oh, and a ship is stuck in sea ice, therefore no global warming!!!1!!eleventy one!"

Neither position is based in defensible logic or on evidenced data.

It's cute that Shrub attacks Nate Drake for not having been on an Antarctic expedition himself, as if this negates any of nate's observations or substantive points... can someone remind me again how many times the Antarctic scientist Nigurath has been to the Southern Continent?

Oh, and I see that the Antarctic Science Professor of Economics is still sniping at his scientific betters - is that straw I see sculpting his Bold Statement?

Fact 1 - Antarctic tourism is Good Capitalism that none of these characters have previously opposed. Why start now?

Fact 2 - Science was done. None of the armchair experts, many of whom have not even ventured south of the equator, have yet seen the final results so there is no basis at all on which to criticise it.

Fact 2 - Tourism and science work well in other models. Ask the Earthwatch Insitute: I can attest first-hand that their volunteers are finacially and practically critical to many serious scientific projects, and much work in the literature would never had appeared had not these non-traditional models been employed.

Fact 4 - From a training perspective alone this trip is of justifiable value, and in this I diverge from Nate who is waiting to see the publication outcomes in order to call it. A trip such as this will have provided much experiential as well as practical benefit to the postgraduate students on board, and for far less cost than would be required to provide comparable experience to the same number of trainee surgeons or lawyers. Economists... well, probably not - I suspect that they'd be cheap to train...

Bernard J. said...

Yeah, I know...

Fact 3...

Thomas Lee Elifritz said...

I just love it when people reread their own posts and find all kinds of horrible spelling and grammer (lol) mistakes. That is sometimes, but not always, more entertaining than the commentary. It even extends to online document and proposal submissions under a deadline too! What we really need is a little AJAX or javascript that toggles the various data overlays in and out. That should be script kiddie stuff.

Albatross said...

Oh dear God, this little "scandal" that the deniers and their apologists have fabricated to try and smear climate science is just bloody pathetic. It also just goes to show that these folks are interested only in trying to smear climate science and scientists, because they cannot argue against the science.

If there were particle physicists or astronomers or scientists from pretty much any other discipline this would be a null story in denierville.

Nigel Persaud et al. = pathetic, desperate know-it alls who love to bully, distort and smear. EOS.

Meanwhile, California and swaths of Australia bake and burn.

Albatross said...

Want a real scandal? Nigel Persaud better hurry up and do a forensic audit of the journal Pattern Recognition in Physics ;)

Hank Roberts said...


“A land ethic, then, reflects the existence of an ecological conscience, and this in turn reflects a conviction of individual responsibility for the health of land.”

I think that's a compliment, albeit premature.