L Band Brightness Temperature Observations over a Corn Canopy during the Entire Growth Cycle

Sensors

Alicia T. Joseph²  Rogier van der Velde¹  Peggy E. O’Neill²  Bhaskar J. Choudhury²  Roger H. Lang³  Edward J. Kim² 

[1] International Institute for Geo-Information Science and Earth Observation (ITC), Hengelsostraat 99, P.O. Box 6, 7500 AA Enschede, The Netherlands; E-Mail:;Hydrological Sciences Branch/614.3, Hydrospheric and Biospheric Sciences Laboratory, NASA/Goddard Space Flight Center, Greenbelt, MD 20771, USA; E-Mails:;Department of Electrical Engineering & Computer Sciences, the George Washington University, Washington, DC 20052, USA; E-Mail:

关键词: field campaign;    L-band radiometry;    vegetation effects;    surface roughness;   

DOI  :  10.3390/s100706980

来源: mdpi

【 摘 要 】

During a field campaign covering the 2002 corn growing season, a dual polarized tower mounted L-band (1.4 GHz) radiometer (LRAD) provided brightness temperature (T_B) measurements at preset intervals, incidence and azimuth angles. These radiometer measurements were supported by an extensive characterization of land surface variables including soil moisture, soil temperature, vegetation biomass, and surface roughness. In the period May 22 to August 30, ten days of radiometer and ground measurements are available for a corn canopy with a vegetation water content (W) range of 0.0 to 4.3 kg m⁻². Using this data set, the effects of corn vegetation on surface emissions are investigated by means of a semi-empirical radiative transfer model. Additionally, the impact of roughness on the surface emission is quantified using T_B measurements over bare soil conditions. Subsequently, the estimated roughness parameters, ground measurements and horizontally (H)-polarized T_B are employed to invert the H-polarized transmissivity (γ_h) for the monitored corn growing season.

【 授权许可】

CC BY   
© 2010 by the authors licensee MDPI, Basel, Switzerland.