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.