Estimating Turbulent Heat Fluxes With a Weak-Constraint Data Assimilation Scheme: A Case Study (HiWATER-MUSOEXE)
作者
摘要
A weak-constraint variational data assimilation (WC-VDA) scheme was developed to estimate turbulent heat fluxes by assimilating sequences of land surface temperature measurements. In contrast to the commonly used strong-constraint VDA system, the WC-VDA approach accounts for the effects of structural and model errors and generates better results. This is achieved by adding a model error term (ω) to the surface energy balance equation. The WC-VDA model was tested at two sites with very distinct hydrological and vegetated conditions: the Daman site (a wet site located in an oasis area and covered by seeded corn) and the Huazhaizi site (a dry site located in a desert area and covered by sparse grass). The two sites represent typical desert-oasis landscapes in the middle reaches of the Heihe River Basin, northwestern China. The results proved that the WC-VDA method performed well over very dry and wet conditions, and the estimated sensible and latent heat fluxes agree well with eddy covariance measurements.
关键词
- atmospheric boundary layer
- atmospheric techniques
- atmospheric temperature
- atmospheric turbulence
- Daman site
- data assimilation
- desert area
- desert-oasis landscapes
- dry conditions
- dry site
- eddy covariance measurements
- Equations
- Evapotranspiration
- Heating
- Heihe River Basin
- HiWATER-MUSOEXE
- Huazhaizi site
- hydrological conditions
- land surface
- Land surface temperature
- land surface temperature (LST)
- land surface temperature measurements
- latent heat
- latent heat flux
- Mathematical model
- middle reaches
- model error term
- Northwestern China
- oasis area
- seeded corn
- Sensible heat flux
- soil
- sparse grass
- strong-constraint variational data assimilation system
- surface energy balance equation
- turbulent heat fluxes
- variational techniques
- vegetated conditions
- Vegetation
- WC-VDA model
- weak-constraint variational data assimilation scheme
- weak-constraint variational data assimilation (WC-VDA)
- wet conditions
- wet site
引用方式
Xu TR, Bateni S.M., Liang SL. Estimating turbulent heat fluxes with a weak-constraint data assimilation scheme: A case study (HiWATER-MUSOEXE). IEEE Geoscience and Remote Sensing Letters, 2015, 12 (1), 68-72.doi:10.1109/LGRS.2014.2326180