Layering
- https://www.rei.com/learn/expert-advice/layering-basics.html
- http://www.coolantarctica.com/Antarctica%20fact%20file/science/clothing_in_antarctica.php
- http://www.artofmanliness.com/2011/12/21/cold-weather-dressing/
- https://en.wikipedia.org/wiki/Extended_Cold_Weather_Clothing_System
- http://www.mcguirearmynavy.com/Genuine-GI/GI-Clothing/Gen-III-ECWCS/
1. Base Layer
The underwear base layer against the skin provides the first layer of insulation and most importantly manages moisture removal, pulling sweat away from the skin.
2. Insulating Layer
The middle insulating layer protects you from the cold by trapping in heat.
For extreme environments, you can wear more than one insulating layer.
3. Shell Layer
The protective outer shell layer shields you from wind, rain, and snow.
For extreme environments, you can wear more than one outer layer.