go to top scroll for more


Projects: Projects for Investigator
Reference Number NE/C003691/1
Title Atmosphere-canopy interaction over complex terrain
Status Completed
Energy Categories Renewable Energy Sources(Wind Energy) 10%;
Not Energy Related 90%;
Research Types Basic and strategic applied research 100%
Science and Technology Fields ENVIRONMENTAL SCIENCES (Earth Systems and Environmental Sciences) 100%
UKERC Cross Cutting Characterisation Not Cross-cutting 100%
Principal Investigator Dr A Ross
No email address given
Energy Resources Research Unit
University of Leeds
Award Type R&D
Funding Source NERC
Start Date 01 January 2006
End Date 31 December 2008
Duration 36 months
Total Grant Value £247,811
Industrial Sectors Transport Systems and Vehicles
Region Yorkshire & Humberside
Programme Standard
Investigators Principal Investigator Dr A Ross , Energy Resources Research Unit, University of Leeds (99.998%)
  Other Investigator Dr I (Ian ) Brooks , School of Earth and Environment, University of Leeds (0.001%)
Prof S (Stephen ) Mobbs , School of Earth and Environment, University of Leeds (0.001%)
Web Site
Objectives 1) The collection of a dataset of flow and thermodynamic measurements (both mean values and turbulent fluxes) within and above a forest situated on a hill. 2) Identification of the significant features of flow over a forested hill which differentiate it from (a) flow over an unforested hill and (b) flow over a flat, homogeneous forest. 3) The validation in near-neutral conditions of first and one-and-a-half order turbulence closure schemes for use within forest canopies over complex terrain. 4) The development of a simple canopy turbulence closure model for stable conditions and comparison of the scheme with the experimental data.
Abstract Land surface fluxes of momentum, heat, moisture and constituents are factors of crucial importance in numerical weather prediction and climate models. They are all strongly influenced by vegetation and forests in particular, where flows and exchanges within the canopy determine the sources and sinks. The understanding of these canopy flows is now quite well developed for extensive areas of flat ground, but many hilly and mountainous areas are either partially or fully forested. To date, models for orographic flow have generally ignored the processes within the forest and parametrize the hill surface using a roughness length. Very recently, theoretical and computational developments have begun to set out a framework for understanding the mean flow within these forest canopies. These suggest that correctly modelling the interaction between the canopy and the atmosphere can have important consequences on mountain and larger scales. There is an urgent need to validate the latest model developments using field measurements, but to date none are available. This project will provide such a validation dataset by collecting several months of measurements within and above a forest covering a small but steep hill. There is as yet little theoretical framework for understanding the turbulence structure within canopies on hills and yetthis is crucial for wind damage and dispersal applications. High resolution turbulence measurements within and above the canopy will provide new insight into the structure of turbulence within the canopy and this will lead to improved turbulence closureschemes for canopy flows. Further numerical modelling incorporating these schemes will extend the range of the predictions to more complex terrain.
Publications (none)
Final Report (none)
Added to Database 28/05/08