HR: 11:35h
AN: H32A-06 [Abstracts]
TI: A One-Dimensional Data Assimilation Experiment Using 3D Eddy Covariance Heat Flux Observations to Improve Land Surface Modelling
AU: Pipunic, R
EM: r.pipunic@civenv.unimelb.edu.au
AF: Department of Civil and Environmental Engineering, The University of Melbourne,
Australia
AU: * Walker, J P
EM: j.walker@unimelb.edu.au
AF: Department of Civil and Environmental Engineering, The University of Melbourne,
Australia
AU: Trudinger, C
EM: Cathy.Trudinger@csiro.au
AF: CSIRO, Marine and Atmospheric Research, Australia
AU: Western, A
EM: a.western@civenv.unimelb.edu.au
AF: Department of Civil and Environmental Engineering, The University of Melbourne,
Australia
AB:
Land surface models such as the CSIRO Biosphere Model are often coupled with weather and climate forecast
models to provide a continuous feedback of latent and sensible heat flux values as the lower boundary condition
for weather and climate forecasting. However, these flux estimates are typically poor due to approximations of
complex physical processes and errors in model forcing data and parameters. Hence, the technique of data
assimilation is commonly applied to improve latent and sensible heat flux prediction, with research focussing on
the assimilation of soil moisture measurements. However, variables such as soil moisture typically share a
weak or uncertain relationship with the latent and sensible heat fluxes in land surface models. This is often
exacerbated by a lack of soil and vegetation property data required to accurately parameterise the models. The
assimilation of latent and sensible heat flux observations to improve land surface model predictions of latent and
sensible heat fluxes and associated soil moisture and temperature states has received very little attention in the
scientific community thus far. In this study, data assimilation was performed using 3D eddy correlation
measurements of latent and sensible heat flux, together with meteorological forcing data from south eastern
Australia. An Ensemble Kalman Filter assimilation algorithm was applied and results validated against 3D eddy
flux data and measured soil moisture and temperature profiles to determine the impact on model estimates of
fluxes and states and whether assimilating latent and sensible heat fluxes is an approvement over soil moisture
assimilation.
DE: 1818 Evapotranspiration
DE: 1840 Hydrometeorology
DE: 1854 Precipitation (3354)
DE: 1855 Remote sensing (1640)
SC: Hydrology [H]
MN: 2007 Joint Assembly