Mj. Russell et al., CONVERSION OF NADIR, NARROW-BAND REFLECTANCE IN RED AND NEAR-INFRAREDCHANNELS TO HEMISPHERICAL SURFACE ALBEDO, Remote sensing of environment, 61(1), 1997, pp. 16-23
Measured nadir-viewed narrow-bond reflectances rn red and near infrare
d channels simulating AVHRR Channels 1 and 2 are compared with measure
d integrated solar spectrum hemispherical albedo. Reflectances and alb
edos rc;ere measured from an aircraft over four widely different veget
ation surfaces in southeastern Tasmania (Australia). A linear function
is used to simultaneously correct for narrow band to broad band conve
rsion errors and to convert nadir viewed reflectances to hemispherical
albedos. While the application of the conversion equation presented i
s limited to the vegetation types of the study, the equation is indepe
ndent of vegetation type. Results indicate that the reflectance front
the rough surface of a forest canopy is not Lambertian and that the us
e of a directional to hemispherical albedo conversion using a Lamberti
an assumption may lead to errors as great as 35%. (C) Elsevier Science
Inc., 1997.