- The Bowen ratio, the ratio of the turbulent surface fluxes of sensible (Hₛ) and latent (Hₗ)
heat, Bo ≡ Hₛ/Hₗ, occurs throughout micrometeorology. It finds application in the Bowen
ratio and energy budget method, where it provides both turbulent heat fluxes when only the
available energy at the surface is known. It can yield an estimate of a missing Hₛ or Hₗ if
the other flux is known. We also suggest that the Bowen ratio may provide the missing
piece needed to infer the surface sensible heat flux from satellite data. For this study, we
analyze almost 9000 eddy-covariance measurements of Hₛ and Hₗ. About half were made
over sea ice; the other half, over the open ocean. These are saturated surfaces where the
surface specific humidity is the saturation value at the surface temperature. Surface
temperatures ranged from -44°C to 32°C and predict the Bowen ratio through the Bowen
ratio indicator, Bo* ¼ cₚ=/(Lᵥ∂Qₛₐₜ/∂ϴ|ϴₛ
. Here cₚ is the specific heat of air at constant
pressure, Lᵥ is the latent heat of sublimation or vaporization, and ∂Qₛₐₜ=∂ϴ is the derivative
of the saturation specific humidity (Qₛₐₜ) with temperature (ϴ). All quantities are evaluated
at the surface temperature, ϴₛ. Although Hₛ and Hₗ can occur in nine possible
combinations, in our data set, three combinations represent over 90% of the cases: Hₛ>0
and Hₗ>0, Hₛ<0 and Hₗ<0, and Hₛ<0 and Hₗ>0. In each of these three cases, the data
suggest Bo ¼ aBo*, where a is 0.40, 3.27, and -0.65, respectively.
- Andreas, E. L., Jordan, R. E., Mahrt, L., & Vickers, D. (2013). Estimating the Bowen ratio over the open and ice‐covered ocean. Journal of Geophysical Research: Oceans, 118(9), 4334-4345. doi:10.1002/jgrc.20295
- American Geophysical Union
|Funding Statement (additional comments about funding)
- The U.S. National Science Foundation supportedAndreas and Jordan in this work with award 10–19322. The U.S.Office of Naval Research supported Andreas with award N00014-12-C-0290 and Andreas, Mahrt, and Vickers with award N00014-11-1-0073.
- This is the publisher’s final pdf.