Rudolf

[Roughquest]

Why do our noses tend to go red when we are cold ?

[enigma884]

Is it because the body channels more blood there when it is cold?

[wvaleriechas]

In cold weather your blood supply is directed to the most important organs rather than extremities like noses fingertips and toes which are not as important as vital organs.

[Ethel]

"when the skin temperature falls below about 10�C, the surface blood vessels dilate (get wider) rather than constrict.

If the temperature falls further periods of blood vessel dilation alternate with periods of constriction.
This is because your body is trying not to lose heat from the extremities, but at the same time wants to supply the skin with blood for oxygen and nutrients.

This phenomenon explains the red cheeks and nose characteristic of frosty weather. "

http://tinyurl.com/68n97r