Topic: Oceanic Heat Budget

Theme: Measurement

Key Concepts:

Satellite Measurement

• Earth's average surface temperature is increasing by about 0.1 degrees C/decade. Thus we need to wait many decades to get accurate measurements of Earth's temperature.
  
• Meterological satellites in polar orbits are used to measure cloud cover
  
• AVHRR (Advanced Very High Resolution Radiometer) is also used to measure cloud cover data (substracted from solar insolation).
  
• Instruments on Polar-orbiting meteorlogical satellites measure the radiation parts of the heat budget.

Heat Fluxes

• Latent-Heat Flux is influenced primarily by wind speed and relative humidity.
• High winds and dry air evaporate much more water than weak winds with relative humidity near 100%.
  
• In Polar regions, evaporation from ice-covered oceans is much less than from open water.
  
• In the Arctic, most of the heat lost from the sea is through leads (ice-free areas). Hence the percent of open water is very important for the arctic heat budget.
  
• Sensible-Heat Flux is influenced primarily by wind speed and air/sea temperature difference.
  
• High winds and large temperature differences cause high fluxes. Think of this as a wind-chill factor for the oceans.
  
• Fluxes are calculated from the correlation of vertical wind and horizontal wind, humidity, and the air temperature.