Titlebar

Export bibliographic data
Literature by the same author
plus on the publication server
plus at Google Scholar

 

A Study of the Internal Boundary Layer due to a Roughness Change in Neutral Conditions Observed During the LINEX Field Campaigns

Title data

Jegede, Oluwagbemiga O. ; Foken, Thomas:
A Study of the Internal Boundary Layer due to a Roughness Change in Neutral Conditions Observed During the LINEX Field Campaigns.
In: Theoretical and Applied Climatology. Vol. 62 (1999) Issue 1-2 . - pp. 31-41.
ISSN 1434-4483
DOI: https://doi.org/10.1007/s007040050072

Abstract in another language

As an aspect of the LINEX field studies (1996-97; Lindenberg near Beeskow, Germany), the characteristics of the internal boundary layer (IBL) that is associated with a step change of the surface roughnesses in neutral constant stress layers was investigated and is reported in this paper. Both smooth to rough (in 1996) and rough to smooth (in 1997) types of flow, have been studied based upon the profiles of mean wind and temperature realised from a 10-m mast and eddy correlation measurements taken at two levels (2 m and 5 m). Depending upon wind direction, the fetch at the site varied between 140 m and 315 m within the wind sector (200° to 340°) used for the field investigations. The height of the IBL, (delta), had been determined from the intersect of the logarithmic wind-profiles below ( 6 m) the interface. Values of (delta) obtained at the experimental site compared fairly well to the existing theoretical/empirical fetch-height relationships of the form: (delta) = a·xb, where a, b, are empirical constants. The ratio for the friction velocities below and above the IBL as measured directly by the eddy correlation technique showed that for fetches less than 250 m there was an increase (decrease) of about 20 % of the momentum flux arising from the smooth to rough (rough to smooth) transitions. Influences of distant obstructions (e.g. bushes, pockets of trees) on the surface flow were markedly important on the examined wind profiles and such can be indicative as multiple IBLs.

Further data

Item Type: Article in a journal
Refereed: Yes
Additional notes: BAYCEER7279
Institutions of the University: Faculties > Faculty of Biology, Chemistry and Earth Sciences > Department of Earth Sciences > Professorship Micrometeorology
Research Institutions > Research Centres > Bayreuth Center of Ecology and Environmental Research- BayCEER
Faculties
Faculties > Faculty of Biology, Chemistry and Earth Sciences
Faculties > Faculty of Biology, Chemistry and Earth Sciences > Department of Earth Sciences
Research Institutions
Research Institutions > Research Centres
Result of work at the UBT: Yes
DDC Subjects: 500 Science
Date Deposited: 24 Sep 2015 09:38
Last Modified: 24 Sep 2015 09:38
URI: https://eref.uni-bayreuth.de/id/eprint/19712