19 March 2010

Movie time sort of

There's a movie site that decided that it would be a good idea to interview non-movie people about their tastes in movies.  I kind of liked the idea, since I'm often disagreeing with movie industry folks about movies.  So when I was invited to answer some movie questions, I did so.  You can see the result at
Robert Grumbine – Movies and the Masses.

I'm kind of impressed at the author's skill there -- finding what must be about the only two scientist characters from movies that I look better than.  (My wife would say that the list is much longer, and maybe she's right.  Just in case, I'm still not taking her in to get her eyes checked.)

But the 'masses' bit, and another part of the article bring up an interesting point about science and scientists, or at least about how I think about it, and that is the role of 'smartness'.

18 March 2010

Climate in many languages

Science is so much an international activity, I tend not to think about where exactly people are from. For that matter, many are 'from' parts of the world that they're not working in. Prompted by a recent email, I've added the language that blogs on my blogroll are in, so that you're not surprised to see Swedish when you go to Emretsson.net, for instance. In that vein, please let me know what language Stig's Klimablogg is in.

While I'm thinking about it, let me also invite your suggestions as to good science, particularly climate-connected, blogs outside of English. Please mention the language and what makes it good.

12 March 2010

Lake Erie Ice

My friends at the Great Lakes Environmental Research Lab sent me word of their nice video of ice on Lake Erie. There was an unusually long cloud-free (or at least little cloud) period, so you can actually see some ice and its motion.

http://www.youtube.com/watch?v=IwW56v1Jt0U for the video.

Something for you to look at while I'm off-net for a few days.

When I'm back on line, I'll be answering some of the questions that are still outstanding. New questions and comments can still come in, just be aware that the moderation delay will be longer than usual. questions here. I'll also be looking in to adding a widget that will let you see the most recent comments. Since the blog is conversational, if a slow conversation, I do take them as an important part of what goes on here. (Or you can subscribe to the comment feed, icon over on the right hand column.)

WUWT trumpets result supporting climate modelling

The recent article at WUWT
NSIDC Reports That Antarctica is Cooling and Sea Ice is Increasing trumpets the observation that Antarctic sea ice is increasing.  This is expected from climate modeling.  Nice to see someone else is picking up on this interesting confirmation of our scientific expectation.

The prediction is old.  In 1992 Manabe and coworkers, in running a changing CO2 experiment, noticed that the Antarctic sea ice cover increased with increasing CO2.  They traced this to increased fresh water on the Antarctic ocean, which derived from increased precipitation -- snow.  They also observed in their model that the Arctic ocean sea ice experienced a marked decline in thickness, and major loss of extent in the summer, but not so large a decrease in the winter.  At the time they wrote, it was still being debated whether there were trends in the Arctic or Antarctic sea ice covers.

The trend in Antarctic ice cover managed to be statistically significant by about 1997, as documented in

D. Cavalieri, P. Gloersen, C. L. Parkinson, J. C. Comiso, H. J. Zwally,
"Observed Hemispheric Asymmetry in Global Sea ice Changes", Science,
278, pp 1104-1106, 1997.  And it was indeed the expected (by Manabe and coworkers) increase.  As well as the expected decrease in the Arctic.

That left the question of the mechanism.  Did Manabe and coworkers identify the correct reason for the sea ice expansion?  Increased snowfall on Antarctic sea ice was documented in 2006 --

Markus, T., and Cavalieri, D. J., "Interannual and regional variability
of Southern Ocean snow on sea ice", Annals of Glaciology, 44, pp 53-57, 2006. (sorry, paywall here).

Since I'm a modeller, I focus on the modelling aspect.  Skeptical science (recently added to blogroll) has a different take about Antarctic sea ice, looking more at atmospheric and ocean temperatures
Watts Up With That's ignorance regarding Antarctic sea ice, with more to come.

11 March 2010

How can annual average temperatures be so precise?

The comments on what should be reproducible raise the subject's question -- since a given thermometer reading is only within, say, 0.8 degrees, how can we claim to know the annual average temperature to 0.01 degrees for the globe?

One thing to remember is that the 0.8 is not the size of the error on every single observation.  Some will be extremely close to correct, and some will be 0.4 off -- large, but not the 0.8.  The 0.8 error is the range that we expect to see 95% of the observations be better than.  Still, with errors that large, how can we get a global average that's within 0.01?

I hit on an experimental way to demonstrate this, without requiring you all to set up thousands of meteorological stations around the world and then collect observations for a year.  Namely, get yourself 8 coins.  If you prefer making computers do things, a spread sheet will work as well, or you can write the program from scratch.

09 March 2010

Technological regress

If you've been reading for a while, you might want to swallow and put down the coffee cup.  I've posted several times about technological progress and have been favorable to it.  And it's correct to think that I'm favorable to technological improvements and expect more to come. 

But not all uses of technology represent progress.  And not all things can be cured by technology. 

07 March 2010

What should be reproducible?

I'll make the assumption that astrophysics is science.  That shouldn't be terribly surprising, given both that folks tend to talk about it as being science, often as being a particularly beautiful branch of science, and that I've studied it myself.  But starting from that assumption suggests that either astrophysics is not science after all, or that many of the complaints about climatology are ill-founded.  At least in the sense that if they should be taken seriously (speakers rejecting the idea that climatology is science) then astrophysics, and quite a lot of other sciences, should be rejected as well.  Now I do know some folks who do reject astrophysics and some other sciences, so some people probably do mean that.

But let's think a bit more about what reproducibility means.  I took it up lightly earlier, regarding pretty much just climate data set reproducibility.  Please excuse the narrow focus as just attention to my own area.  I'll broaden scope some here.

On one extreme end of notions of reproducibility is the idea that anybody, anywhere, should be able to reproduce your results -- or else you aren't doing science.  I don't think that's actually been held to be a requirement for science at any time in history, so such folks are arguing for a change in how science is done.  Maybe they're right; let's think about it.  As with many ponderings, this goes for a while ....

04 March 2010

How to handle personal attacks

It's always a pleasure, in part because of how rare and difficult it is, to see someone respond well to a host of personal attacks.  One of those exceptional, and funny, responses is from Rebecca Watson, the 'skepchick'.  Apparently quite a few folks have decided that rather than respond to the content of her arguments, they'll comment about her eyebrows and other such irrelevancies. 

Follow through to the end of the video to her exactly correct conclusion about such arguments.

h/t Pharyngula

03 March 2010

Why is the ocean cold?

Folks reading headlines about record warm oceans might be surprised by this question. But it's a real question, if perhaps from a different viewpoint than you might think.

If we look at the surface of the ocean, we see that most of the ocean is warm. The presentation at the link over-emphasizes the polar regions -- they're actually much less of the earth's area. Even so, over half the ocean -- surface -- is warmer than 20 C.

So you might figure that the volume of the ocean would also be some moderately warm figure, maybe a bit colder since cold water sinks, but still fairly warm. Surely over 10? In fact, the volume of the ocean -- average up every blob of water there is -- averages 3.5 C. Go back to the surface map and take a look at how much of the ocean is that cold. Answer: Not much. Even less when you allow for the fact that the map is exaggerating how big the polar regions are (I get about 14% of the ocean surface was at least that cold on February 26th). The importance of those small areas of cold water is that there is no refrigerator in the ocean. Once water leaves the surface of the ocean (except for one even smaller exception I'll get to), there's no way to make the water any colder. So if you see water that's -1.0 C in the ocean, you know it came from somewhere that had water at least as cold as -1.0 C. It could have been even colder -- the original cold blob might have mixed with a warmer blob of water.

Some of you might have objected up there when I mentioned that the average ocean temperature is 3.5. There's a fairly popular error that says the deep ocean has to be 4 C. It runs this way: Water is densest at 4 C, so as you cool a body of water, once it reaches 4 C all this cold water sinks to the deeps. As you cool the surface further, the water is less dense, so it quits sinking. That leaves you with 4 C water in the deep.

02 March 2010

Coping with Math

I confess that for the most part, math has been something that I enjoy and have fun with.  'Coping' hasn't so much been my experience; but I have known plenty of people for whom it was more difficult, and even highly unpleasant, activity.  Since it sometimes turns in to an obstacle that scares people away from doing science, and I like science as well as the math, I do keep an eye out for books that might help people past that obstacle.

My favorite book in that realm is Sheila Tobias' Overcoming Math Anxiety.  Her story was being one of those people who had been scared out of math and science.  Later, she decided that she liked physics and would slog through the math she had to, that was preventing her from doing the science she liked.  Along the way, she discovered many myths that she had bought in to, things that produced anxiety in her when math was mentioned.  Hence the title. 

In talking with people, anxiety stands out as a major barrier.  One of the myths I'll mention here is that some people just have some magical 'math gene' that makes it easy for them, and nobody else can do any math.  But it's only math that needs this magical gene.  Nobody says "I can't play basketball, I don't have the magic gene for it."  Basketball, we all know, you can play regardless.  If you practice more, you'll get better.  If you want to play professionally, then, yes, you need good genes.  And that's probably also true for mathematics.  But you don't need to be a professional level basketball player to enjoy playing the game.  And you don't need to be a professional level mathematician to do science.

01 March 2010

Science humor

No, I won't inflict any mathematician/engineer/scientist jokes on you.  (Not that I couldn't ....)  I've been reminded recently of some good science humor cartooning.

Online, you might enjoy:
PHD Comics

A science cartoonist I've enjoyed for years and recently reread his collections Einstein Simplified and Einstein Atomized is Sidney Harris.  You can get an online taste here

And, though it was never really a science cartoon, Gary Larson's Far Side is a favorite of mine, and was quite popular among scientists.