Validation of Mean and Turbulent Parameters Measured from the Aircraft in the Marine Atmospheric Boundary Layer

다국어 초록 (Multilingual Abstract)

The SEMAPHORE (Structure des Echanges Mer-Atmosphère,Propriétés Océaniques/ Recherche Expérimentale) experiment,which took place between 04 Oct. and 17 Nov. 1993, was conducted over the oceanic Azores current located in the Azores basin. The SST (Sea Surface Temperature) field was characterized in the SEMAPHORE area (31o-38oN; 21o-28oW) by a large meander with a SST gradient of about 1oC per 100 km. In order to study the evolution of the MABL (Marine Atmospheric Boundary Layer) over the ocean, the mean and the turbulent data were evaluated by the measurement with two aircraft and a ship in different meteorological conditions. Three cases of low pressure and three cases of high pressure are mainly presented here. For the six cases, the satellite images (NOAA) did not show any relation between the SST field and the cloud cover. At each flight level, the decrease of the SST with the altitude due to the divergence of the infrared radiation flux from the ocean is 0.25oC per 100 m. For the comparison between the two aircraft, the mean thermodynamic and dynamic parameters show a good agreement except for the temperature. The dispersion of the sensible heat flux is larger than that of the latent heat flux due to the weak sensible heat flux over the ocean both in the intercomparison between two aircraft and in the comparison between the aircraft and the ship.

참고문헌 (Reference)

1 Guymer, T. H., "Transfer processes at the air-sea interface" 308 : 253-273, 1983

2 Brown, E. N., "The use of pressure fluctuations on the nose of an aircraft for measuring air motion" 22 : 171-180, 1983

3 Rogers, D. P., "The marine boundary layer in the vicinity of an ocean front" 46 : 2044-2062, 1989

4 Lambert, D., "The marine atmospheric boundary layer during SEMAPHORE. Part I: Mean vertical structure and nonaxisymmetry of turbulence" 125 : 495-512, 1999

5 Eymard, L., "Study of the air-sea interactions at the mesoscale: the SEMAPHORE experiment" 14 : 986-1015, 1996

6 Kwon, B. H., "Structure of the marine atmospheric boundary layer over an oceanic thermal front: SEMAPHORE experiment" 130 : 25159-25180, 1998

7 Reddy, R. C., "Observations of a mesoscale circulation over the Gulf Stream region" 2 : 21-39, 1994

8 Druilhet, A., "Moyens aéroportés utilisés durant l’expérience COCAGNE" 19 : 369-398, 1985

9 Giordani, H., "Monitoring the atmospheric and surface variability during the SEMAPHORE campaign: A data re-analysis with the ARPEGE operational system" 103 : 25047-25060, 1998

10 Käse, R. H., "Meandering of the subtropical front south-east of the Azores" 300 : 245-246, 1982

11 Lenschow, D. H., "Length scales in the convective boundary layer" 43 : 1198-1209, 1986

12 Arya, S. P., "Introduction to Micrometeorology" Academic Press 420-, 2001

13 Shaw, W. J., "Intermittency and the organization of turbulence in the near-neutral marine atmospheric boundary layer" 28 : 918-928, 1985

14 Dupuis, H., "Inertial dissipation method applied to derive turbulent fluxes over the ocean during the Surface of the ocean, Fluxes and Interaction with the Atmosphère/Atlantic Stratocumulus Transition Experiment (SOFA/ASTEX) and Structure des Echanges Mer-Atmosphère, Propriete des Heterogeneites Oceaniques: Recherche Experimentale (SEMAPHORE) experiments with low to moderate wind speeds" 102 : 21115-21129, 1997

15 Mahrt, L., "Heat and Moisture Fluxes over the Fine Forest in HAPEX in “Land Surface Parameterization”" Springer-Verlag 285-, 1991

16 Panofsky, H. A., "Atmospheric Turbulence, Model and Methods for Engineering Application" John Wiley and Sons 397-, 1984

17 Lambert, D., "Aircraft to aircraft intercomparison during SEMAPHORE" 103 : 25109-25123, 1999

18 Nicholls, S., "Aircraft observations of the Ekman layer during the Joint Air-Sea Interaction Experiment" 111 : 391-426, 1985

19 Lenschow, D. H., "Aircraft Measurements in the Boundary Layer in Probing the Atmospheric Boundary Layer" 396-, 1986

20 Friehe, C. A., "Air-sea fluxes and surface layer turbulence around a sea surface temperature front" 96 : 8593-8609, 1991

21 Käse, R. H., "A quasi-synoptic survey of the thermocline circulation and water mass distribution within the Canary basin" 91 : 9739-9748, 1986