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Land Surface Remote Sensing and Their
Application in Climate Models
Our group has been actively
engaged with scientists who collectively
have considerable experience in climate
modeling and in the development of various
MODIS algorithms to make better use of the
latest NASA satellite data to improve the
representation of land in climate models.
Using the NASA remote sensing land products,
such as the land surface
albedo, leaf
area index (LAI), fraction of
photosynthetically
active radiation (FPAR), fractional
vegetation cover, soil
emissivity and plant
phenology, we
compared these data with climate models to
identify and attribute the model
deficiencies in land surface parameters and
parameterization, generated more realistic
and consistent land surface datasets,
developed simple parameterization schemes
based on satellite observation for climate
models, and evaluated the impacts of
improvements on the simulated climatology of
land surface variables in climate models.
For example, our studies found that the
largest albedo
biases over semiarid and snow covered
vegetated surfaces and the largest
emissivity
biases over the arid and semi-arid regions
in climate models, which are mainly
attributed to lack of land surface
heterogeneity characterization and
inaccurate specification of land surface
parameters in the models. See details
here

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Figure.
Improved land surface air
temperature in CLM2 with the
usa of
the MODIS data. The upper panel (a,b)
shows temperature bias compared to
observations in winter (DJF) and
summer (JJA) and the lower panel (c,d)
shows corresponding temperature
differences due to the use of MODIS
data. (Tian
et al., JGR, 2004) |
Our current research
efforts have also been focused on the
evaluations of soil moisture results from
climate models and the generation of a
vegetation water content dataset using
passive microwave observations. Because of
its sensitivity to both soil moisture and
vegetation properties, and the ability to
penetrate the atmosphere, passive microwave
radiation observed on TOA has demonstrated
unique strength for monitoring land surface
characteristics. For more details, click
here |