13 February 2014

Science Fair Judges

I'll write about and to science fair judges before a note to the students.  A joke I made today got its due chuckle, but there's a real point to it.  I observed of judges that "We're very scary people."

Now, we know ourselves, and scientists in general are not scary people at all.  Even more so, if anything, those of us who do science fair judging.  We tend to be parents with school age kids ourselves, or at least not too long since we were (and, in my case, I'm still an uncle to kids this age).  And to like talking with kids and have a certain degree of understanding of (in today's case) 14-18 year olds. 

On the other hand, I can recall ages back, when I was a 26 year old finishing his PhD and presenting at an international scientific meeting.  Only about 200 people in the room (on the other hand: 200 people in the room!).  And I was 26 and nearly done with a PhD, not a 14-18 year old in perhaps my first talk with a scientist.  But I was seriously nervous, before, during, and after.  Most of that was unnecessary, as, again, scientists aren't actually a very scary bunch.  (It did work out in my accidental favor, more in a moment.) 

It was a great relief to survive the talk (nobody threw anything!  er, ok, that didn't happen to anyone, and I'd never seen it happen before.  But ... I was nervous).  And it was thrilling when, unforced, one of the 'Big Name in Field' people present said they'd liked my presentation.

I try to pass this along (not the big name in field aspect, which I'm not, but at least a good word somewhere).  And try to de-scarify for the students I talk to about their work.  We're still pretty scary to the students.  But I enjoyed my chats with students, and hope they came away with a bit more understanding of doing science.

The 'more in a moment':  The later postscript on my presentation was about my nerves.  Back then, when I was nervous, I spoke slower.  Opposite of most people, but it worked in my favor.  The thing was, at an international meeting, many people (in this case, about 2/3rds) are not native English speakers.  A speed that a nervous native is capable of racing through can be all but impossible for a non-native to follow.  Since I slowed down, I was more understandable to the group.  Several folks thanked me for my consideration.  They didn't know it was terror :-)

11 February 2014

PIOMAS ice volume anomaly q

Q: I've got a question that you may be able to answer with your sea ice hat on.

Why is it that the minimum volume anomaly of ice appears in mid summer and not in September when the minimum volume happens? See piomas.
(From Alastair)

A: I'm hard-pressed to tell what season the anomaly extremes are occurring from this graph, but can say that your reading isn't surprising to me.  At the seasonal minimum of ice volume, you're at the minimum -- so it is relatively difficult to get even lower.  Late winter, towards the maximum doesn't have that problem -- since it's maximum, there's lots of room to go lower.  But the Arctic is cold in winter, so it's going to pile up a lot of additional mass (from the prior minimum) pretty consistently.  The place/time that there's the most room for decreasing the ice volume is a time of year when the ice volume hasn't already declined a lot, but it is melting rapidly -- early- to mid- summer.

As you also see from the figure, the main trend is the year-round decline.  For your question, we're looking at the timing of largest excursions below the line. 

The converse question, for largest excursions above the trend, is that I'd expect those in late fall - early winter, during the freeze-up season.  Then, there isn't much volume, and it's freezing fast.  A couple weeks earlier start to freeze-up makes a comparatively large difference.

10 February 2014

Evaluating 2013 sea ice outlook estimates

Very late wrap on my 2013 sea ice season guesses, but, as I was thinking in early August, the straight statistical one busted pretty badly.  The observed (NSIDC) September Average sea ice extent was 5.35 million km^2.  The guesses were:

The original outlooks (end of May) were:
3.9 million km^2 -- Grumbine, Wu, Wang statistical
4.1 million km^2 -- Wu, Grumbine, Wang model-based
4.4 million km^2 -- Wang, Grumbine, Wu model-based statistical
The end-June Wu et al. estimate was 4.7 million km^2.
The end-July Wu et al. estimate is 4.57 million km^2.
As I suggested then, I'm going to get back in to the statistical approach to try to fix it up.  While we don't expect excellent estimates from it, if it's using a sound basis, it shouldn't be wrong by this much.  I have some ideas on how to do it. 

Still, better estimates than Stephen Goddard's end of August (the 26th) prediction -- Doubling of Arctic Ice in 2013.  Doubling September 2012 would have meant 7.26 million km^2.  (I was just touring web sites, and saw this article, which reminded me that I hadn't posted the evaluation of my forecasts.)