The Effects of Shallow Cold Flows in the PBL State. Analysis of Experimental Datasets during Alpaca-PBL Winter Field Experiment.
Résumé
During winters, the absence of solar radiation combined with clear skies and weak synoptic forcing enables cold pooling in the complex topographic basins of Interior Alaska. Under such conditions, shallow cold flows (SCF) originating from north facing semi-enclosed basins are able to penetrate the planetary boundary layer (PBL) of the open south-facing basins. This paper analyzes the effects of SCF in the state surface layer during the ALPACA field experiment in Fairbanks, Alaska. Surface radiation and turbulent fluxes combined with high resolution thermodynamic profiling yielded new insights describing the effect of SCF in the PBL state.