caa a22 4500 475777743 CHVBK 20180406123635.0 cr unu---uuuuu 170329e20001001xx s 000 0 eng 10.1023/A:1002790424133 doi (NATIONALLICENCE)springer-10.1023/A:1002790424133 Spatial And Temporal Variability Of Mixed-Layer Depth And Entrainment Zone Thickness [Elektronische Daten] [P. Hägeli, D. Steyn, K. Strawbridge] Mixed-layer depth and entrainment zone thickness areextracted from two large lidar data sets with arecently developed technique. The entrainment fluxratio (which is often used to model entrainment inatmospheric boundary-layer models) can be calculatedfrom these two quantities. This ratio is generallybelieved to be in the range of 0.1 and 0.4. Aqualitative analysis of time series (MERMOZ II dataset) confirms this range of values under equilibriumconditions (afternoon hours), but also shows that itclearly underestimates the importance of entrainmentduring the morning hours when the mixed layer isgrowing most rapidly. An examination of the spatialdistribution of the entrainment flux ratio (Pacific'93 data set) shows that this parameter is spatiallyhighly variable, even during ‘equilibrium' hours inthe afternoon. In regions where the boundary layerhas to adjust to new boundary conditions at theground, values much larger than 0.4 can be observed. Although these results can only be interpretedqualitatively, they suggest that currently usedentrainment parameterisations in boundary-layer modelsare not sufficient to capture the entrainment processproperly. Kluwer Academic Publishers, 2000 Entrainment flux ratio nationallicence Entrainment zone thickness nationallicence Lidar nationallicence MERMOZ II nationallicence Mixed-layer depth nationallicence Pacific '93 nationallicence Hägeli P. Atmospheric Science Program, The University of British Columbia, Vancouver, B.C., Canada aut Steyn D. Atmospheric Science Program, The University of British Columbia, Vancouver, B.C., Canada aut Strawbridge K. Air Quality Processes Research Division, Meteorological Service of Canada, Egbert, ON, Canada aut Boundary-Layer Meteorology Kluwer Academic Publishers 97/1(2000-10-01), 47-71 0006-8314 97:1<47 2000 97 10546 https://doi.org/10.1023/A:1002790424133 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1023/A:1002790424133 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Hägeli P. Atmospheric Science Program, The University of British Columbia, Vancouver, B.C., Canada aut NATIONALLICENCE 700 1- Steyn D. Atmospheric Science Program, The University of British Columbia, Vancouver, B.C., Canada aut NATIONALLICENCE 700 1- Strawbridge K. Air Quality Processes Research Division, Meteorological Service of Canada, Egbert, ON, Canada aut NATIONALLICENCE 773 0- Boundary-Layer Meteorology Kluwer Academic Publishers 97/1(2000-10-01), 47-71 0006-8314 97:1<47 2000 97 10546 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer