• Hadley cells lower level motion
• scale height for water vapor much less than for dry air

Zonal average Temperature ([T]):

- "[ ]" means zonal average -- see Appendix

• Fig. 3.11:
  • -troposphere, stratosphere
  • -tropopause (location & slope)
  • -coldest [T]
  • -gradients concentrated in midlats.

  -seasonal chg. (figs 3.11 & 3.14)

• -hemispheric differences (3.12 & 3.13)

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Radiative balance models

• - obtains a vertical structure of T field by specifying absorber present & incoming radiation
• -Method/assumptions:
  • - local radiative balance for each layer, T independent of time
  • - absorber present (fig 6.2) incorporated into optical depth
  • - absorbed radiation dI must be emitted for energy balance e*dtau*sec(phi)
  • - use method of moments to replace irradiance dI/dtau term with easier handled dF/dtau radiance term.
  • - everything cast in terms of IR emission.
• - first examine F independent of tau (implies no solar absorption, convection, or heat fluxes)
• - have 4 main "problems" compared to observations:
  1. - heat fluxes are observed, so:
     • model is valid at 38 N or 38 S on annual average
     • or must add fluxes to model, making dF/dtau nonzero
  2. - superadiabatic lapse rates
  3. - T discontinuity @ top but especially @ bottom
  4. - lapse rate always >0, but that not observed in upper stratosphere
• "fixes" for these problems to be examined next lecture