Surface heat flux Hs

Turbulent heat flux upward from the surface, measured by fast response turbulence instruments using the identity Hs = cpñ.wŒTŒ., where wŒ is the fluctuation in vertical wind speed and TŒ is the fluctuation in temperature, and the average is taken over about one hour. A typical value of Hs in the daytime is about 200 w/m2 (J/sm2) and at night is about –20 W/m2. Glossary 199