28 September 2010

Does Lake Superior Remember the Last Ice Age?

I'm more than a little surprised by this post by Steven Goddard.  His answer to my title question is yes.  That he's wrong isn't very interesting.  We all make mistakes, and particularly so when speaking outside areas that we've studied.  The two main physical processes which show his error are interesting in their own right, and I'll take this chance to discuss them -- they are rivers (which say 200 years should be noticeable), and what happens to fresh water at 4 C (which says the memory is 1 year [oops, 6 months]).

First, I'll take a look at a less interesting error that minimal self-checking would have pointed to a difficulty.  But that introduces a useful tool -- the 'sanity check'.  Namely, he suggests that the reason Lake Superior is still cold is because it's so large that it is still adjusting to the end of the last ice age.  That's about 10,000 years ago.  Ok, suppose this line of reasoning is true.  While Superior is large, is it tiny compared to the oceans.  If Superior takes 10,000+ years to adjust, something 10 times bigger should take 100,000+ years to adjust.  The ocean is about 100,000 times larger (in volume) than Lake Superior.

27 September 2010

Science Cafe

This Thursday (September 30th) I'll be talking about ice, and, better, yet, answering questions about ice at the Annapolis Cafe Scientifique.  The time will be 6 PM instead of the usual 6:30.  Same location as usual -- Cafe 49 West.  Local folks are invited, and non-local are welcome to pose questions here.

24 September 2010

Kitchen experiments

Some simple, if possibly messy, fun.  Ingredients: Water and corn starch, baking powder and vinegar.

The baking powder and vinegar mix to release carbon dioxide gas.  If you put it inside something with a tight cap that can blow off, you've got a 'rocket'.  Just be sure to aim it away.  I don't really remember well, but I think equal vinegar and baking powder is the right recipe.  But it's something to experiment with.

Corn starch and water is a chance to explore the mechanical properties of matter.  (read: mess around while claiming to be doing science)  Ordinary fluids, like air or water, react straightforwardly to pushing on them.  If you push, they move out of the way.  Push harder, they move out of the way faster.  Corn starch and water (again, I think it's equal amounts, but experiment) are a different kind of thing.  Set a marble on top of the mixture and it will sink through.  Throw the marble at it, and it will bounce. !?  Experiment.  It makes a difference how fast you push.  Lots of room for experimentation.

Anyone else have comparably simple experiments?

20 September 2010

Unity of science and reaching decisons

The next two paragraphs were in a private email list where there was then a request that I make the comments public.  The situation was my response to another scientist, the topic at hand being the scope of the conspiracy that would be involved in pulling of a hoax that CO2 is a greenhouse gas, etc..  I also talked here a while back about the unity of science:

I think a crucial part of that error is a failure to understand how science works.  While you and I (and others) look at it and see masses of scientists from different areas and reach a conclusion, others don't.  The extra piece of knowledge we have is that science has to hang together as a coherent picture.  If climate people were seriously wrong about the radiative properties of CO2, then CO2 lasers would not work.  And so on through a very, very long list.  Conversely, if climate types were seriously wrong about CO2's radiative properties, laser specialists would look at the climate work and point to the errors and that'd be the end of the wrong climate CO2 work.

Instead, they take the view that science is story-telling.  Laser physicists go along with the climate people because the climate folks are telling a story that the laser folks like, not because there's any particular evidence in favor of it.  The "It's a liberal conspiracy", or "They only say this because they want to impose one world government" responses are part of this.  The he said -- she said journlistic line is exactly this, as the science is presented as two stories the reader is chosing between.  They think the scientists are doing the same thing.  (How would they know differently?)

Back to the present:
I'll also mention, in terms of how people could tell what scientists actually do, that John Wilkins is taking ideas on sources for describing how it is that scientists reach conclusions:
How Scientists Think: A Book Proposal
The Scientists Operating Manual
While I'm mentioning John, h/t also to this xkcd cartoon, which captures a certain crowd (an attitude I've occasionally borrowed at least part of) quite well:
xkcd physicists

10 September 2010

Scientists are real people

If you are accustomed to the media representation of scientists, my subject line is something of a shock.  What, do I mean scientists aren't all junior Dr. Spock's off Star Trek?!  Contrary to everything you've ever seen on TV and films?!  Well, yes.  We're human, no less than anyone else on the planet, and unlike fictional Vulcans.

That's relevant to the post, not so much for content, but at the reason that comments and posts have somewhat gotten away from me.  There were many good comments in the What is a good experiment? thread, and I haven't commented there myself.  (I'll encourage you to go have a look.).  And there have been good comments to later notes that I, again, haven't commented on (see the list of most recent comments that's, currently, buried way to the bottom of the page).  Not that my comments are required, or any such thing.  But, since I like conversation, it pains me to not be engaging the way I'd like to be.  (Don't worry, even if I'm not commenting, I am definitely reading.  I read far faster than I compose.)

For the subject at hand, the answers are entirely mundane -- 'real person' -- sorts of reasons.  I've been doing other things.  I'm a parent with 3 kids.  And they've been doing things over the last month.  Good things for them, and me (at least to spectate).  But they do tend to mean that I'm focusing some of my time, energy, and attention in places other than the blog.  Some (many) scientists are parents (and grandparents).  Many of us are very concerned about parenting well.  Or least are seriously interested in our kids.  Even with my youngest being 20, I still think there's room, and need, for a parent.  And they're great kids, so who wouldn't want to be involved?!  Or at least sitting in the back of the audience cheering.

I'm also a spouse.  My spouse and I have been doing things together in evenings and weekends which are very good and which we enjoy together -- visiting friends, having friends over, going places, and so forth.  Good, 'real person', things, but while I'm doing those, I'm not blogging.

And I have a day job different from the sorts of things that I write on the blog.  There's a small degree of transference.  I can point out to you that my May predictions of September's ice extent are looking to have bracketed the likely result pretty well.  The high (model-based) figure was 5.13 and the low (statistically-based) figure was 4.78.  We passed below 5 in the last few days.  Probably won't be as low for the monthly average as 4.78.  But the spread between the two forecasts was fairly small, and succeeding in bracketing reality with that narrow range is ... not bad.  I'll have more to say once we get to the end of the month and see what really happens.  The day job has been showing up interesting things, which turns around to mean more time at the office, and less time taken from my lunch hour to write on the blog.

The end of the month provides a chance for me to meet up with folks who are local.  I'll be speaking at the Annapolis Science Cafe, on Thursday, the 30th of September.  More about that to come.  It'll be about ice (you're shocked, I know).

Last night I earned 'Beastmaster' status.  My wife has two dogs.  (Her dogs -- she's had them longer than she's known me.  We've only been married a little over 4 years; newlyweds.)  Both are small dogs, of, as Dave Barry said, of the 'pillow' family.  The older one, Tater, is pushing 12 and has his hair growing over his eyes -- to the point that he often can't see what is around him, like walls.  One reason that hair grows so long is that he has traditionally (I'm told) reacted violently whenever anyone approached with scissors to trim off the overhang.  Last night I sat him down, solo, and trimmed his bangs.  No sedation or armies to hold him down.  He's doing better now.  Here's a picture of him during 'snowmageddon' last February (the snow is about 30 cm, 1 foot, next to him; double that farther away from the door).  He'd just had his hair trimmed (after sedation, at the veterinarian's).  He had far less vision last night before I started trimming.

In between all that, I've been nudging an idea towards being able to submit it for serious publication.  It's difficult doing that from home.  I'm used to publishable ideas being things I work on at work.  This one, however, is not related to what I do at work beyond the fact that it involves the earth.  Not really close enough to persuade the folks who sign my paycheck that I should be devoting work time to it.  Once I've sent it off for a round of preliminary review by friends who have some good general science knowledge (to see if I've made a generally well-formed argument), I'll be thinking more bloggy things.  Not least being various things to talk about here regarding doing science and some offshoots of interest.  The climate cycles 1 post is one such already.  There are more to come.  Not least, while that first climate cycles post talked about seasonal variations, we also should take a look at daily variations.  Same as we (middle and high-latitude residents) expect summer to be warmer than winter, we (all) expect daytime to be warmer than night time.  That expectation makes it climate.  Figuring out by just how much becomes science.

And there are the usual 'real life' sorts of things -- paying bills, getting my car fixed, trying to take care of an injured shoulder, blah, blah, and very blah.  Scientists are real people, with all the same issues as anybody else.  Irritates me that so many seem to think we're Vulcans.  Plus, of course, that we stand in closets in between times of saying something or other annoying and irrelevant to the human issues at hand.  We all have the usual problems, responsibilities and joys of being 'real people'.  Some of that affects the blog.  All of it is just the usual, for scientists, same as for anybody else.  I'll be getting back to more regular writing here in the near future, as this part of my regular life becomes more active.

01 September 2010

Constructing an analysis 1: Drop in a bucket

'Analysis' is what we call an attempt to represent the state of the atmosphere/ocean/sea ice/... given a set of observations. One such analysis is the global surface air temperature analysis. That, then, spawns efforts to find a global mean temperature, or global mean temperature trends, and so forth. Several of the recently-added blogs aim to study that, in one way or another. That particular one is not my interest in two different ways.

One is, I'm an oceanographer, so I'm more interested in a sea surface temperature (sst) analysis. The other is, most of the interest in the surface air temperature analysis seems to come from its role as a detector of climate change. On the scale of things, I consider this the second weakest climate change indicator. The only thing weaker, in my view, is the so-called 'Hockey Stick'. But enough raw opinion.

Regardless of what it is you're trying to analyze, and what your reason for doing so is, there are quite a few ways of setting about doing so objectively. The fact that there are many makes this the first of something like eight notes I'll be writing up on the idea. There turn out to be many different ways of making an analysis, each objective, each with strengths, each with weaknesses.

The simplest one, if not as simple as you might think, is the 'drop in a bucket' method.