How modern jackets manage heat: Left, a typical insulated shell; right, layers that trap air, block wind and reflect infrared heat without adding bulk.
January 10, 2026
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January 10, 2026 1 a.m.
The science behind how your winter jacket keeps you warm
The science behind how your winter jacket keeps you warm
As the weather grows cold this winter, you may be one of the many Americans pulling their winter jackets out of the closet.