An Auxiliary tool to determine the height of the boundary layer
2005 (English)In: Boundary-Layer Meteorology, Vol. 115, 423-432 p.Article in journal (Refereed) Published
Results from radiosoundings, performed both over land and over sea, show that the ascent rate of a radiosounding balloon, the vertical velocity of the balloon, can be used to determine the height of the boundary layer. In many cases the balloon has a higher ascent rate in the boundary layer and a lower, less variable, ascent rate above. The decrease in ascending velocity appears as a jump at the top of the boundary layer. Two examples of potential temperature profiles for unstable stratification and one profile for stable conditions are shown with the corresponding ascent rates. A comparison between the boundary-layer height determined from potential temperature profiles and from ascent rates is presented for a larger dataset. The different ascent rates of the balloon in the boundary layer and above can be explained by a decrease in drag on the balloon in combination with a lowering of the critical Reynolds number in the boundary layer caused by turbulence. Hence, by simply logging the time from release of a radiosonde, it is possible to obtain additional information that can be used to estimate the height of both the unstable and stable boundary layers.
Place, publisher, year, edition, pages
2005. Vol. 115, 423-432 p.
Ascent rate, boundary-layer height, drag coefficient, radio sounding, Reynolds number
Meteorology and Atmospheric Sciences
IdentifiersURN: urn:nbn:se:uu:diva-76459DOI: doi:10-1007/s10546-004-1424-5OAI: oai:DiVA.org:uu-76459DiVA: diva2:104371