Abstract
Double-layered structures found over the Baltic Sea are investigated using radiosoundings and lidar measurements. Situations with double-layer structures are also simulated with the regional model REMO in a realistic manner. The double layer consists of two adjacent well-mixed layers, with a sharp inversion in between.
Results from radiosoundings show that the double-layer structure over the Baltic Sea mainly occurs during the autumn with thermally unstable stratification near the surface. The structure is present in about 50 % of the radiosoundings performed during autumn. The presence of the double-layer structure cannot be related to any specific wind direction, wind speed or sea surface temperature.
The lidar measurements give a more continuous picture of the time evolution of the double-layer structure, and show that the top of the lower layer is not a rigid lid for vertical transport. Two possible explanations of the double-layer structure are given, (i) the structure is caused by `advection' of land boundary-layer air over the convective marine boundary layer or, (ii) by development of Sc clouds in weak frontal zones connected to low pressure systems. Also the forming of Cu clouds is found to be important for the development of a double-layer structure.
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References
BALTEX: 1995, 'Baltic Sea Experiment BALTEX. Initial Implementation Plan', in Technical Report, International BALTEX Secretariat, GKSS Research Center, Geesthacht, Germany, 84 pp.
Bergstrüm, H. and Smedman, A.: 1999, 'Wind Climatology for a Well-Exposed Site in the Baltic Sea', J. Wind Eng. 23, 133–142.
Büsenberg, J.: 1998, 'Ground Based Differential Absorption Lidar for Water-Vapor and Temperature Pro ling: Methodology', Appl. Optics 37, 3845–3860.
Büsenberg, J. and Linné, H.: 2002, 'Laser Remote Sensing of the Planetary Boundary Layer', Meteorol. Z. 11, 233–240.
Gryning, S. and Batchvarova, E.: 2002, 'Marine Boundary Layer and Turbulent Fluxes over the Baltic Sea: Measurements and Modelling', Boundary-Layer Meteorol. 103, 29–47.
Hennemuth, B. and Jacob, D.: 2002. 'One Year Measurement and Simulation of Turbulent Surface Heat Fluxes over the Baltic Sea', Meteorol. Z. 11, 105–118.
Hennemuth, B., Rutgersson, A., Bumke, K., Clemens, M., Omstedt, A., Jacob, D., and Smedman, A.: 2003, 'Net Precipitation over the Baltic Sea for One Year Using Models and Data-Based Methods', Tellus 55A, 352–367.
Jacob, D. and Podzun, R.: 1997, 'Sensitivity Studies with the Regional Climate Model REMO', Meteorol. Atmos. Phys. 63, 119–129.
Jacob, D., den Hurk, B. V., Andræ, U., Elgered, G., Fortelius, C., Graham, L., Jackson, S., Karstens, U., Küpken, C., Lindau, R., Podzun, R., Rockel, B., Rubel, F., Sass, B., Smith, R., and Yang, X.: 2001, 'A Comprehensive Model Inter-Comparison Study Investigating the Water Budget during the BALTEX-PIDCAP Period', Meteorol. Atmos. Phys. 77, 19–43.
Källstrand, B.: 1998, 'Low Level Jets in a Marine Boundary Layer During Spring', Contr. Atmos. Phys. 71, 359–373.
Majewski, D.: 1991, 'The Europa-Modell of the Deutscher Wetterdienst', in Seminar Pro-ceedings ECMWF 2, pp. 147–191.
Nicholls, S. and Leighton, J.: 1986, 'An observational Study of the Structure of Stratiform Cloud Sheets. Part I: Structure'. Quart. J. Roy. Meteorol. Soc. 112, 461–480.
Sempreviva, A. and Gryning, S.-E.: 2000, 'Mixing Height over Water and its Role on the Correlation between Temperature and Humidity Fluctuations in the Unstable Surface Layer', Boundary-Layer Meteorol. 97, 273–291.
Smedman, A., Andersson, T., Batchvorova, E., Bumke, K., Büsenberg, J., Clemens, M., Fischer, B., Grynibg, S.-E., Hennemuth, B., Hyvünen, R., Hügstrüm, U., Jacob, D., Jo-hansson, C., Kangas, M., Melas, D., Michelson, D. B., Omstedt, A., Peltomaa, A., Peters, G., Rutgersson, A., Säntti, K., and Tammelin, B.: 2000, 'PEP in Baltex-Final Report(1997–2000)Part I: Summary (EU-Project PEP in BALTEX, Contract ENV4-CT97–0484)', Available from Department of Earth Sciences, Air and Water Science, Villavägen 16, SE-752 36 Uppsala, Sweden.
Smedman, A., Bergstrüm, H., and Grisogono, B.: 1997, 'Evolution of Stable Internal Boundary Layers over a Cold Sea', J. Geophys. Res. 102, 1091–1099.
Smedman, A., Gryning, S.-E., Büsenberg, J., Tammelin, B., Andersson, T., Omstedt, A., and Bumke, K.: 1998, 'PEP in BALTEX. A Pilot Study of Evaporation and Precipitation in the Baltic Sea', in Second Study Conference on BALTEX. Rügen, Germany, pp. 206–207.
Smedman, A., Hügstrüm, U., Bergstrüm, H., Rutgersson, A., Kahma, K., and Pettersson, H.: 1999, 'A Case-Study of Air-Sea Interaction during Swell Conditions', J. Geophys. Res. 104, 25, 833–825, 851.
Sundararajan, R. and Tjernstrü m, M.: 2000, 'Observations and Simulations of a Non-Stationary Coastal Atmospheric Boundary Layer', Quart. J. Roy. Meteorol. Soc. 126, 445– 476.
Tjernstrüm, M. and Smedman, A.: 1993, 'The Vertical Turbulence Structure of the Coastal Marine Atmospheric Boundary Layer', J. Geophys. Res. 98, 4809–4826.
Turton, J. D. and Nicholls, S.: 1987, 'A Study of the Diurnal Variation of Stratocumulus Using a Multipe Mixed Layer Model', Quart. J. Roy. Meteorol. Soc. 113, 969–1009.
Wulfmeyer, V., and Büsenberg, J.: 1998, 'Ground-based Differential Absorption Lidar for Water-vapour and Temperature Pro ling: Assessment of Accuracy, Resolution, and Meteorological Applications', Appl. Optics 37, 3825–3844.
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Johansson, C., Hennemuth, B., Bösenberg, J. et al. Double-layer structure in the boundary layer over the baltic sea. Boundary-Layer Meteorology 114, 389–412 (2005). https://doi.org/10.1007/s10546-004-1671-5
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DOI: https://doi.org/10.1007/s10546-004-1671-5