at Google ScholarTitle 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 > Professor 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 |