Sensitivity of bed shear stress estimated from vertical velocity profiles: the problem of sampling resolution     

Pascale M. Biron  Stuart N. Lane  Andr G. Roy  Kate F. Bradbrook  Keith S. Richards 《地球表面变化过程与地形》1998,23(2):133-139

Bed shear stress in open channel flows is often estimated from the logarithmic vertical velocity profile. However, most measuring devices used in the field do not allow for flow velocity to be measured very close to the bed. The lack of near-bed measurements is a critical loss of information which may affect bed shear stress estimates. Detailed velocity profiles obtained from a field acoustic Doppler velocimeter over three different bed roughnesses clearly show that the inclusion of near-bed points is critical for the estimation of bed shear stress in a shallow river environment. Moreover, the results indicate that using the full flow depth instead of the bottom 20 per cent of the profile generates an underestimation of the shear stress when flow is uniform. © 1998 John Wiley & Sons, Ltd.  相似文献   

The Atlantic Meridional Overturning Circulation and the subpolar gyre observed at the A25-OVIDE section in June 2002 and 2004     

Pascale Lherminier  Herlé Mercier  Thierry Huck  Claire Gourcuff  Fiz F. Perez  Pascal Morin  Artem Sarafanov  Anastasia Falina 《Deep Sea Research Part I: Oceanographic Research Papers》2010,57(11):1374-1391

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