- Apr 5, 2002
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Windchill: a still-air temperature that would have the same cooling effect on exposed human skin as a given combination of temperature and wind speed.
From: http://www.islandnet.com/~see/weather/life/windchill.htm
I was curious if cold-blooded animals were affected the same way we were to windchill. They are, but they don't feel as bad as we do in the cold. We must maintain a higher temperature, so we feel more cold. If a snake and a human were side by side in any air temperature at any wind speed, both core temperatures would be the exact same, after they equalize with the surrounding air temp. Wind speed just hurries the process.
FYI for you all.
From: http://www.islandnet.com/~see/weather/life/windchill.htm
...furthermoreAs warm-blooded animals, or poikilotherms, human physiology employs various body processes to maintain the central core temperature near 37oC (98.6oF). With a skin temperature around 33.9oC (93oF), the core-skin temperature differential is "optimal," and we generally feel neither hot nor cold -- a state we term "comfortable." (Please note our discussion here is general in nature and assumes a healthy human body. Individuals may vary widely in their responses to their thermal environment due to a large number of body factors.)
When heat cannot be lost quickly enough to maintain the body's ideal temperature differential, internal heat builds up and we feel "hot." The body's thermal regulators soon respond to increase our heat loss through increased perspiration, urination and desire for water, and decreased metabolism.
On the other side of the thermal regulatory continuum, when internal heat is lost too rapidly, we begin to feel "cold," and the body again reacts. This time, shivering, "goose flesh," decreased perspiration and increased metabolism are some of the main responses.
How we feel under prevailing environmental thermal conditions, therefore, is more a response to the rate of body heat gain or loss rather than to the absolute temperature. Thus, we may feel cool in the summer under temperatures considered balmy during winter.
Unlike other animals, humans have the short-term option of aiding the body in heat regulation by adding or removing clothing to maintain an overall comfort level. Thus, we rarely venture out into the cold outdoors naked. If we did, we would lose heat rapidly, and under extreme conditions could face death in a few hours of exposure.
How fast we lose heat depends primarily on the air temperature and the wind speed. (Exposure to full sun can counter some of the heat loss to cold temperatures and windy conditions, and being wet can increase heat loss through evaporation.) Under calm or near calm conditions, we lose heat faster as environmental temperatures become colder. But when the wind blows faster than a threshold speed, we begin to lose heat at a rate, much more rapid than the loss due to temperature differential alone.
This is utterly false. The wind speed, however strong, does not change the actual air temperature. If we placed two identical thermometers side-by-side, one exposed to the wind and the other sheltered, they will read the same unless other factors such as radiation or moisture on the sensor are affecting one of them.
Thus, no matter what the equivalent windchill temperature may be, the temperature of a living body (human or animal) or an inanimate object (e.g., a car radiator) exposed to the air will never drop below the actual air temperature unless wet (when evaporative cooling may lower the surface temperature). Therefore, exposed water or other liquids will not freeze unless the air temperature is below their freezing point.
I was curious if cold-blooded animals were affected the same way we were to windchill. They are, but they don't feel as bad as we do in the cold. We must maintain a higher temperature, so we feel more cold. If a snake and a human were side by side in any air temperature at any wind speed, both core temperatures would be the exact same, after they equalize with the surrounding air temp. Wind speed just hurries the process.
FYI for you all.