Submitted by Anonymous on Sun, 08/28/2011 - 16:33
Forums
Adaptations of Marine Worms in Antarctica

Hi Mike,

In wanting to pass on correct information to my first graders, I need to clear something up in my own mind.

The weather report shown for August 26th in your Winfly journal said the temperature was -60°, but the wind chill was 32°. How does that work? Here in Florida the wind chill is given to show it feels colder than the actual temperature.

Am I reading the report wrong, or is there more to it?

You seem to really be enjoying your experience. I am too! Tell Theodore we are thinking about him!

Karen mrsdannecy.blogspot.com

Sun, 08/28/2011 - 18:39

Michael League

Hey Karen, Oh, I was hoping no one would pick up on that error. You are too
good. There was an error on that report. I was hoping everyone would
look at the sunrise time and ignore the wind chill. You are right -
wind chill should always be equal to or lower than the air temperature.
Wind chill should not be higher than air temperature.
For you (not the first graders), wind chill is actually calculated using
a formula. It factors in the air temperature and wind speed. It is
supposed to be a representation of what it feels like to us outside, by
factoring in evaporative cooling - the effect of moisture evaporating
from your skin (which makes you feel cooler). Think about getting out
of the pool and a strong breeze blowing - as those water droplets
evaporate off your skin, it feels cooler than if you were dry.
Okay, none of that will work with first graders. So, here's how I might
try to explain it to first graders:
Temperature is what a thermometer measures. It's actually measuring the
air. Wind chill is what it feels like to us. This involves people
thinking about the air temperature and the wind speed. You could do a
little demo in the classroom with a fan. The faster the fan blows the
cooler the kids feel, even though a thermometer would still read the
same temperature. That's just like us when the wind blows down here in
Antarctica.
In Florida, you could also go the other way and talk about heat index.
On days when it's really hot AND humid, the moisture doesn't evaporate
very well. Your body can't cool itself as well and therefore it feels
warmer than the actual air temperature.
We're going to do more with wind chill when we get out on the sea ice
later this week. Great question! Reply back if my answer didn't help
and we'll let someone else on the team try...
Mike

Mon, 08/29/2011 - 01:19

Anonymous

Hi Mike,
You answered my question just fine. Thanks for the idea of how to explain it to my students.
So was the temperature really -60°? That is mind boggling to me!
Stay warm!
~Karen

Mon, 08/29/2011 - 19:39

Michael League

Karen, That's great! I'd be really interested to know how much first
graders from Florida can take from that conversation. I imagine that
must be really hard to gain understanding when your local conditions are
so different.
As for the temperature, everything I am reporting is right from the
thermometers. The -60˚F is at the South Pole Station about 800 miles
miles south of us. So far, the coldest temperature we've recorded at
McMurdo since we arrived is -33˚F with a wind chill of –49˚F. I have to
be honest: at some points you can't tell cold from really cold - it just
all feels the same.
Mike
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