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2001-08-23
That brings something to my attention. Is the
new formula for wind-chill just a new way to calculate effective temperature or
is it a new way to calculate heat loss? If it is a new way to calculate
heat loss, then the established heat loss data in watts per square metre must
also be modified, using the new formula.
One of the reasons Environment Canada did not use
equivalent temperature was because of the difficulty in determining it.
Since the heat curve was only accurate for wind speeds above 10 km/h,
interpolating the data to provide an equivalent temperature based on the same
heat loss with no wind could not be done accurately. Is this new formula
suppose to take care of this problem? Is that what the hoopla is all
about?
Does anyone have any idea on what this formula
looks like?
John
----- Original Message -----
Sent: Thursday, 2001-08-23 00:16
Subject: [USMA:14997] Re: CNN and the
NWS
In a message dated
2001-08-22 08:25:39 Eastern Daylight Time,
[EMAIL PROTECTED] writes:
Below is my email to CNN regarding their website page on the
new wind-chill
scale. It's not really about metric, so skip it if you
don't want to read
about a non-metric issue. But i thought some of you
might be interested in
the subject anyhow.
Regards,
Bill
Hooper
============
MSG. TO CNN via their "response"
link that I had to hunt for on their web
site.
--------------------------------------
Your article badly
confuses the wind chill with the temperature. They are
not the same
thing and cannot be compared or equated.
You wrote: "The wind chill
index measures how wind speed affects outdoor
temperatures that are felt
by the human body. "
No it does not. The wind chill does not
"affect" the temperature in any way.
You wrote:"The public may have
trouble with the new system at first because
it makes temperatures
appear warmer than they did under the old index."
No they do not. It
makes WIND-CHILLS (not temperatures) appear higher than
the wind-chills
appeared under the old index.
You wrote: "Brown also said that
people in colder climates will have to
adjust themselves mentally to the
newly calibrated temperatures."
They are NOT newly calibrated
temperatures; they are newly calibrated
WIND-CHILL values. The two are
not the same thing.
You wrote: "You'll have to kind of recalculate
your feeling of how cold it
actually is out there"
No you won't.
It is not actually any colder. The temperature is not lower
because of
the wind-chill; it is the WIND-CHILL that is lower because of
the
effect of the wind.
You could also tell them that
Environment Canada, contrary to their article,
uses watts per square meter
to describe windchill, and mentions a 'perceived'
lower temperature only
as an afterthought.
Carleton
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