Changes in Earth’s ReflectanceE. Palle and others
We correlate an overlapping period of earthshine measurements of Earth’s reflec-
tance (from 1999 through mid-2001) with satellite observations of global cloud
properties to construct from the latter a proxy measure of Earth’s global shortwave
reflectance. This proxy shows a steady decrease in Earth’s reflectance from 1984
to 2000, with a strong climatologically significant drop after 1995. From 2001 to
2003, only earthshine data are available, and they indicate a complete reversal of
the decline. Understanding how the causes of these decadal changes are appor-
tioned between natural variability, direct forcing, and feedbacks is fundamental to
confidently assessing and predicting climate change.
Science 6 May 2005: Vol. 308. no. 5723, p. 825 DOI: 10.1126/science.1106484
FuenteEn resumen, el albedo de la tierra decrecio desde 1984 al 2000 segun las medidas. Desce 2001 a 2003 la tendencia es inversa. El forzamiento radiativo correspondiente a la disminucion del albedo global es de 6W/m^2, muy superior a los 2.4W/m^2 estimados del CO2