OCN 5401. Chapter 3 Heat Transfer Instructor: Dr. George A. Maul [email protected] / X 7453. Heat Flux (W·m -2 = J·s -1 ·m -2 ). Q s – radiation from the sun Q b – back radiation from Earth Q e – evaporative heat loss or gain Q h – sensible heat loss or gain
Instructor: Dr. George A. Maul
[email protected] / X 7453
Qt = Qs – Qb – Qe – Qh – Qv
Index of Refraction (η2/η1) = V1/V2
ηwater-air = 1.333 (at 20°C)
CSUN: What is the solar constant?
If TSUN = 5775K, QSUN = ?
The solar constant isn’t constant!
Inflow = Outflow
CSUN(1-A)πr2 = 4πr2σT4
If A=0.3 and CSUN=1367 W·m-2, what is T=?
Earth’s mean temperature balance
requires an extra term
QGHE: What is the greenhouse effect?
TEarth: What is Earth’s temperature?
A: Is Earth’s albedo fixed?
How would Earth’s temperature change if the albedo changed from 30% to 29%?
If TEARTH(A=30%) = 288K, TEARTH(A=29%) = ?
Relative Humidity (RH) and Saturation Vapor Pressure (es)
Example: RH = ?
Tair = 30°; Tdew point = 10°
es = 39 mb; eair = 12 mb
Evaporation from the Sea Surface
Qe = ρwaterE·L
E is in meters per second, and latent heat of evaporation
L= 2495 x 103 J·kg-1
Seasonal Sea Level
Upper few millimeters of the Sea Surface
Sea Surface Temperature (SST) – Skin Temperature and Bulk Temperature