PSD Roving Ship Calibration Standard for AirSea Fluxes

PSD Roving Ship Calibration Standard for Air-Sea Fluxes: Example Ronald Brown • PSD turbulence sensors mounted on the Ronald H. Brown foremast West of Chile (left). Comparison of NOAA PSD, WHOI ORS Buoys (W 12 -8, W 12 -9, Q 13 -1, W 13 -2) and the ship observations (SCS) of air temperature (upper right) and relative humidity (lower right). The ship air temperature shows a bias of 1 C. Fairall ESRL/PSD High Resolution Data from Ships

Evaluation of Gridded Flux Products with Direct Ship Observations OAFLux and ERA-Interim gridded flux products compared with PSD ship observations from the R/V Investigator for CAPRICORN 2016. Time series at daily scale compares PSD with WHOI OAFlux for (a) Sensible heat flux, SHF (b) Latent heat flux, LHF; (c&d) same as a&b but with ERA-Interim at 3 -hourly scale. Fairall ESRL/PSD High Resolution Data from Ships

The PSD COARE Gas Flux Parameterization The COARE gas transfer parameterization is a physicallybased scaling approach where the total transfer velocity of some gas, X, is represented as the sum of a viscous transfer at the air-ocean interface plus a bubblemediated component. Here Scw is the Schmidt number on the water side, αx is the solubility of the gas, u*υ the viscous friction velocity, F is a function, and f. W the fraction of ocean surface covered by whitecaps. The constants A and B are adjusted to fit covariance measurements of the air-sea fluxes of trace gases. In this formalism, one set of A and B values should fit all gases described by (1). We have recently made a major step forward in generalizing the COARE met and gas versions using numerical simulations from the UNSW (Australia) wave model that has been run at selected wind speeds from 1 to 60 m/s. An example of fits of dimensionless roughness to wave is shown on the upper right. The parameterization of whitecap fraction, fw, is shown on the lower right. This new approach will allow whitecap fraction to be based on wave parameters instead of wind speed. Aerodynamic roughness normalized by significant wave height as a function of (u*/cp). Lines are shown for USNW wave model simulations at 4 different forcing wind speeds. Fw as a function of 10 -m wind speed: COARE 3. 6 G, blue dots; wave Reynolds number fit from Brummer et al. Fairall ESRL/PSD High Resolution Data from Ships(2017), green circles; average observations from the HIWINGS field program, red symbols.