"Turbulent Exchange at Vegetated Surfaces and Evaluation of
Estimates of Canopy Structure using SIR-C Data"
REPORT FOR NASA SIR-C PROJECT JPL Contract 958445:
PI: Kyaw Tha Paw U Co-PIs: Susan Ustin, Roger Shaw, Jack
Paris
This project has concentrated on two major
areas, as summarized by the project title: an analysis of the
nature of turbulent exchange as affected by the physical and biological
properties of plant canopies, the sensitivity of the exchange
processes to the properties, and the error associated with remotely
sensing (both RADAR and optical) the properties needed for estimating
turbulent transport. Much of the project was devoted to the two
former topics, with several major findings resulting from the
partial support of this contract. There still remains much research
in the area covered by our project, and we hope we an continue
research beyond September 1997. The main findings concerning
turbulent exchange processes were that canopy height, leaf area
index, physiological response, and moisture status are the main
plant ecosystem factors affecting exchange processes while some
degree of spatial heterogeneity can be accommodated in estimating
fluxes without significant error. A spin-off from this research
was that a new micrometeorological method for estimating exchange
processes was developed, where the high frequency trace of a scalar
such as CO2 is used to determine the scalar flux (such as photosynthesis).
In addition, in conjunction with other funded research, a higher-order-closure
model for turbulent transfer int he plant canopy was developed
for CO2 , water vapor, heat, aerosols, and momentum. It was also
found that modelling of the plant canopy-atmosphere interaction
is more accurate using sophisticated higher-order-closure models
than using simpler flux-resistance or gradient-flux models.
Currently the higher-order closure plant-atmosphere model is
being coupled with a mesoscale model (UCD/Goddard Space Flight
Center nonhydrostatic Mesoscale Atmospheric Convection model)
for testing at the Howland, Maine supersite. Data are being gathered
for the terrain and meteorological conditions during the overpasses,
for input into the model. Preliminary tests of the coupled model
over a simplified island-ocean site (in the Solomon Islands, a
site which maximizes spatial heterogeneity with the ocean- island
contrast) shows great sensitivity to the manner in which the plant-atmosphere
coupling is modelled. Remote sensing analyses have concentrated
on developing algorithms for determining leaf and canopy properties,
both absorption and scattering processes, and stand structure
attributes. We have applied a neural network, using SIR-C L and
C band VV and HH polarizations, trained with field biomass data,
to predict spatial variation in biomass at the Howland, Maine
supersite. SIR-C results tested on additional data show the
net accurately estimates high biomass ranges, where it has a nearly
linear response, while it is insensitive at low values of biomass.
Spatial variation in gap structure and gap sizes, important in
turbulence characteristics, were predicted using spatial correlation
statistics at different scales. We have developed new parameters
using optical sensors or the merging of optical and radar datasets
to obtain horizontal and vertical distributions of canopy parameters
needed as inputs into the turbulence models.
References partially or entirely funded from
SIR-C:
1996 Zhang, M., S.L. Ustin, E. Rejmankova, and E.W.
Sanderson. Monitoring of Pacific coast salt marshes using
remote sensing. Ecological Applications (in
press 8/96).
1996 French, N.H.F., E. Kasischke, R. D. Johnson, L. L.
Bourgeau-Chavez, A. L. Frick and S. L. Ustin. Estimating
fire-related carbon flux in Alaska boreal forests using
multi-sensor remote sensing data. AGU Chapman Conference on
Biomass Burning and Climate Change (in press,
1996).
1996 Xiao, Q.-F., S.L. Ustin, and W.W. Wallender. A spatial
and continuous surface-subsurface hydrologic model.
Journal of Geophysical Research-Atmospheres 101, ND23:
29565-29584.
1996 Govaerts, Y.M., S. Jacquemoud, M.M. Verstraete, and S.
L. Ustin. Three-dimensional radiation transfer modeling in
a dicotyledon leaf. Applied Optics 35: 6585-6598.
1996 Ustin, S.L. , Q.J. Hart L. Duan and G. Scheer.
Vegetation mapping on hardwood rangelands in California,
International Journal of Remote Sensing 17:
3015-3036.
1996 Ustin, S.L., W.W. Wallender, L. Costick, R. Lobato,
S.N. Martens, J. Pinzon, and Q.F. Xiao. Modeling
terrestrial and aquatic ecosystem responses into Hydrologic
Regime in a California watershed. Sierra Nevada Ecosystem
Project, Final Report, Volume III: 275-308
+ 22 figures.
1996 Jacquemoud, S., S.L. Ustin, J. Verdebout, G. Schmuck,
G. Andreoli, and B. Hosgood. Estimating leaf biochemistry
using the PROSPECT leaf optical properties model. Remote
Sensing of Environment 56: 194-202
1996 Palacios-Orueta, A., and S. L. Ustin. Multivariate
statistical classification of soil spectra. Remote Sensing
of Environment 57: 108-118.
1996 Grossman, Y.L., S.L. Ustin, E. Sanderson, S.
Jacquemoud, G. Schmuck and J. Verdebout, Critique of
Stepwise Multiple Linear Regression for the Extraction of
Leaf Biochemistry Information from Leaf Reflectance Data.
Remote Sensing of Environment 56: 182-193.
Paw U, K.T., Qiu, J. , Su, H.B., Watanabe, T., and Brunet,
Y., 1995. Surface renewal analysis: a new method to obtain
scalar fluxes without velocity data. Agric. For. Meteorol.
74:119-137.
Qiu, J., Paw U, K.T. and Shaw, R.H., 1995. Pseudo-wavelet
analysis of turbulence patterns in three vegetation layers.
Boundary-layer Meteorol. 72:177-204.
1995 DeFries, R., Field, C., Fung, A., Justice, C., Los, S.,
Matson, P., Matthews, M., Mooney, H., Potter, C., Prentice,
K., Sellers, P., Townshend, J., Tucker, C., Ustin, S.,
Vitousek, P. Mapping the land surface for global
atmosphere-biosphere models: toward continuous
distributions of vegetation's functional properties.
Journal of Geophysical Research-Atmospheres 100: 20, 867-
882.
Paw U, K.T. and Su, H-B., 1994. The usage of structure
functions in studying turbulent coherent structures and
estimating sensible heat flux. pp. 98-99. In preprints,
21st Conference on Agricultural and Forest Meteorology,
March 7-11, 1994, San Diego, California. American
Meteorological Society, Boston, MA.
Qiu, J., Paw U, K.T. and Shaw, R.H., 1994. Pseudo-wavelet
analysis of turbulence patterns in three vegetation layers.
pp. 106-109. In preprints, 21st Conference on Agricultural
and Forest Meteorology, March 7-11, 1994, San Diego,
California. American Meteorological Society,
Boston, MA.
Paw U, K.T., 1994. Development of a higher order closure
turbulence model for simulating particulate, pollen and
spore transport within plant canopies. pp. 401-402. In
preprints, 11th Conference on Biometeorology and
Aerobiology, March 7-11, 1994, San Diego, California.
American Meteorological Society, Boston, MA.
Pereira, A.R., and Paw U, K.T. 1994. A surface renewal
description of the exchange of scalars between full canopies
and the atmosphere. pp. 104-105. In preprints, 21st
Conference on Agricultural and Forest Meteorology, March 7-
11, 1994, San Diego, California. American Meteorological
Society, Boston, MA.
Spano, D., Snyder, R.L., Paw U, K.T. and DeFonso, E., 1994.
Verification of the surface renewal method for estimating
evapotranspiration. pp. 98-99. In preprints, 21st
Conference on Agricultural and Forest Meteorology, March 7-
11, 1994, San Diego, California. American Meteorological
Society, Boston, MA.
Patton, E.G., Shaw, R., Paw U, K.T. and Moeng, C-H., 1994.
A comparison of two large-eddy simulations of turbulent flow
above and within a forest canopy. pp. 88-91. In
preprints, 21st Conference on Agricultural and Forest
Meteorology, March 7-11, 1994, San Diego, California.
American Meteorological Society, Boston, MA.
1993 Ustin, S.L., M.O. Smith, and J.B. Adams. Remote
Sensing of Ecological Processes: A strategy for Developing
Ecological Models Using Spectral Mixture Analysis. In J.
Ehlringer and C. Field (Eds.) Scaling Physiological
Processes: Leaf to Globe. Academic Press, New York, p.339-
357.
1993. Gamon, J.A., C.B. Field, D.A. Roberts, S.L. Ustin, and
V. Riccardo. Functional patterns in an annual grassland
during an AVIRIS overflight. Remote Sensing of Environment
44:239-253
Paw U, K.T. and D. A. Braaten, 1993. Large aerosol rebound
or reentrainment: who wins after all these years. in
Abstracts, Twelfth Annual Meeting, American Association for
Aerosol Research, October 11-15, 1993, Oak
Brook, Illinois.
Paw U, K.T., 1993. Using surface renewal/turbulent coherent
structure concepts to estimate and analyze scalar fluxes
from plant canopies. Annales Geophysicae 11(supplement
II):C284.
Paw U, K.T., 1993. Investigating soil-plant-atmosphere
biometeorological interactions using higher-order closure
models. Annales Geophysicae 11(supplement
II):C284.
Paw U, K.T., Y. Brunet, S. Collineau, R.H. Shaw, T. Maitani,
J. Qiu and L. Hipps, 1992. On coherent structures in
turbulence within and above agricultural plant canopies.
Agric. For. Meteorol. 61:55-68.
Paw U, K.T. and D.A. Braaten, 1992. Experimental evidence
of the importance of rebound in net deposition of particles.
Aerosol Sci. Tech. 17:278-288.
Paw U, K.T., 1992. Development of models for thermal
infrared radiation above and within plant canopies. J.
Photogrammetry Remote Sens. 47:189-203.
Braaten, D.A. and K.T. Paw U, 1992. A net deposition model.
Aerosol Sci. Tech. 17:289-302.
Gao, W., R.H. Shaw and K.T. Paw U, 1992. Conditional
analysis of temperature and humidity microfronts and
ejection/sweep motions within and above a deciduous forest.
Boundary Layer Meteorol. 59:35-57.
Paw U, K.T., 1992. Rebound and reentrainment of large
particles. in Precipitation Scavenging and Atmosphere-
Surface Exchange, Vol. 2, coordinators Schwartz, S.E. and
Slinn, W.G.N., Hemisphere Publishing Co., Washington. pp.
1153-1161.
Zhang, Changan, R.H. Shaw and K. T. Paw U, 1992. Spatial
characteristics of turbulent coherent structures within and
above an orchard canopy. in Precipitation Scavenging and
Atmosphere-Surface Exchange, Vol. 2, coordinators Schwartz,
S.E. and Slinn, W.G.N., Hemisphere Publishing Co.,
Washington. pp. 741-751.
Paw U, K.T., 1992. A discussion of the Penman form
equations and comparisons of some equations to estimate
latent energy flux density. Agric. For. Meteorol. 57:297-
304.
Braaten, D.A. and K. T. Paw U, 1992. A Stochastic particle
resuspension and deposition model. in Precipitation
Scavenging and Atmosphere-Surface Exchange, Vol. 2,
coordinators Schwartz, S.E. and Slinn, W.G.N., Hemisphere
Publishing Co., Washington. pp. 1143-1150.
1991. Ustin, S.L., C.A. Wessman, B. Curtiss, E. Kasischke,
J. Way, and V.C. Vanderbilt. Opportunities for using the
EOS imaging spectrometers and synthetic aperture radar in
ecological models. Ecology 72: 1934-1945.
Paw U, K.T. and Y. Brunet, 1991. A surface renewal measure
of sensible heat flux density. pp. 52-53. In preprints,
20th Conference on Agricultural and Forest Meteorology,
September 10-13, 1991, Salt Lake City, Utah. American
Meteorological Society, Boston, MA.
K.T. Paw U, 1991. Anisotropy of thermal infrared exitance
above and within plant canopies. pp.369-374. In Vol. 1, 5th
International Colloquium on Physical Measurements and
Signatures in Remote Sensing. European Space Agency, Paris,
France ESA SP-319.
Zhang, Changan, R.H. Shaw and K.T. Paw U, 1991. Translation
velocity of turbulent coherent structures within and above
an orchard canopy. pp. 193-194. In preprints, 20th
Conference on Agricultural and Forest Meteorology, September
10-13, 1991, Salt Lake City, Utah. American Meteorological
Society, Boston, MA.
Brunet, Y., K.T. Paw U and L. Prevot, 1991. Using the
radiative surface temperature in energy budget studies over
plant canopies. pp.557-560. In Vol. 2, 5th International
Colloquium on Physical Measurements and Signatures in Remote
Sensing. European Space Agency, Paris, France
ESA SP-319.
Paw U, K.T., R.H. Shaw and T. Maitani, 1990. Gravity waves,
coherent structures and plant canopies. pp. 244-246. In
preprints, Ninth Symposium on Turbulence and Diffusion,
April 30-May 3, 1990, Roskilde, Denmark. American
Meteorological Society, Boston, MA.
Paw U, K.T., 1990. Coherent turbulent structures:
implications for plant biometeorology. p. 27. in
Biometeorology: Part I (Abstracts), Proceedings of the
Twelfth International Biometeorological Congress, August 3,
1990-Sept. 3, 1990, Vienna, Austria. Edited by Driscoll,
D., Leith, H., and Machalek, A.