The Lagrangian stochastic model for estimating footprint and water vapor fluxes over inhomogeneous surfaces.

Journal Article (Journal Article)

This study investigated a two-dimensional Lagrangian stochastic dispersion model for estimating water vapor fluxes and footprint over homogeneous and inhomogeneous surfaces. Over the homogeneous surface, particle trajectories were computed from a 2-D Lagrangian model forced by Eulerian velocity statistics determined by Monin-Obukhov similarity theory (MOST). For an inhomogeneous surface, the velocity and atmospheric stability profiles were computed using a second-order Eulerian closure model, and these local profiles were then used to drive the Lagrangian model. The model simulations were compared with water vapor flux measurements carried out above an irrigated bare soil site and an irrigated potato site. The inhomogeneity involved a step change in surface roughness, humidity, and temperature. Good agreement between eddy-correlation-measured and Lagrangian-model-predicted water vapor fluxes was found for both sites. Hence, this analysis demonstrates the practical utility of second-order closure models in conjunction with Lagrangian analysis to estimate the scalar footprint in planar inhomogeneous flows.

Full Text

Duke Authors

Cited Authors

  • Hsieh, C-I; Katul, G

Published Date

  • January 2009

Published In

Volume / Issue

  • 53 / 1

Start / End Page

  • 87 - 100

PubMed ID

  • 19034532

Electronic International Standard Serial Number (EISSN)

  • 1432-1254

International Standard Serial Number (ISSN)

  • 0020-7128

Digital Object Identifier (DOI)

  • 10.1007/s00484-008-0193-0


  • eng