@InProceedings{SaatchiRoDeLuAlDu:2002:MeVeAe,
author = "Saatchi, Sassan and Rodriguez, Ernesto and Denning, Scott and Lu,
Lixin and Alvala, Regina Celia dos Santos and Dubayah, Ralph",
title = "Measuring Vegetation Aerodynamic Roughness Over the Amazon Basin",
year = "2002",
organization = "International LBA Scientific Conference, 2.",
keywords = "METEOROLOGIA, Bacia Amaz{\^o}nica, Aspereza da
superf{\'{\i}}cie, vegeta{\c{c}}{\~a}o, medi{\c{c}}{\~o}es,
Regi{\~a}o Amaz{\^o}nica (Am{\'e}rica do Sul), Surface
roughness, vegetation, measurement, Amazon region (South
America).",
abstract = "The aerodynamic roughness length (Z0)is an important parameter to
determine the vertical gradients of mean wind speed and the
conditions for momentum transfer over a vegetated or bare rough
surface. Over vegetated surfaces, the aerodynamic roughness length
has a simple one-to-one relationship with the rms height of the
vegetation at the top of the canopy. Once this roughness length is
determined for a surface, it does not change with wind speed,
stability or stress. During the LBA experiment the Regional
Atmospheric Modeling System (RAMS)with flexible horizontal and
vertical resolution will be used in conjunction with other models
to simulate the atmospheric circulation and trace gas
concentration and transport at various scales. This model is
suitable to determine the effect of surface roughness parameter at
trace gas transport both at local level for LBA study areas and on
at the regional level for the entire Amazon basin. In this paper,
we present the estimation of this parameter from two sources:
1)From a sample SRTM (Shuttle Radar Topography Mission)data over
one of the LBA study areas. The cross correlation between two
interferometric SRTM images will be used to estimate the rms
height of the vegetation at 90 m resolution and relate that to
aerodynamic roughness. This methodology will be applied to the
entire SRTM data (when it becomes available)to estimate the
roughness length over the basin. 2)Various statistical moments of
the JERS-1 image mosaic in fusion with other regional data sets
will be used in a semi-empirical model to estimate the vegetation
roughness length over the entire basin at 1 km resolution. Both
parameters will be integrated into the RAMS model to demonstrate
the effect of spatially explicit roughness length on trace gas
transport simulations and to test the impact of errors associated
with the estimation process.",
conference-location = "Manaus, Br",
conference-year = "7-10 July 2002",
label = "10218",
targetfile = "9298.pdf",
urlaccessdate = "01 maio 2024"
}