Bibcode
Goode, P. R.; Pallé, E.; Yurchyshyn, V.; Qiu, J.; Hickey, J.; Montañés-Rodriguez, P. ; Chu, M.-C.; Kolbe, E.; Brown, C. T.; Koonin, S. E.
Referencia bibliográfica
Journal of the Korean Astronomical Society, vol. 36, S1, pp. S83-S91
Fecha de publicación:
6
2003
Número de citas
2
Número de citas referidas
2
Descripción
There are terrestrial signatures of the solar activity cycle in ice core
data (Ram & Stoltz 1999), but the variations in the sun's irradiance
over the cycle seem too small to account for the signature (Lean 1997;
Goode & Dziembowski 2003). Thus, one would expect that the signature
must arise from an indirect effect(s) of solar activity. Such an
indirect effect would be expected to manifest itself in the earth's
reflectance. Further, the earth's climate depends directly on the
albedo. Continuous observations of the earthshine have been carried out
from Big Bear Solar Observatory since December 1998, with some more
sporadic measurements made during the years 1994 and 1995. We have
determined the annual albedos both from our observations and from
simulations utilizing the Earth Radiation Budget Experiment (ERBE) scene
model and various datasets for the cloud cover, as well as snow and ice
cover. With these, we look for inter-annual and longer-term changes in
the earth's total reflectance, or Bond albedo. We find that both our
observations and simulations indicate that the albedo was significantly
higher during 1994-1995 (activity minimum) than for the more recent
period covering 1999-2001 (activity maximum). However, the sizes of the
changes seem somewhat discrepant. Possible indirect solar influences on
the earth's Bond albedo are discussed to emphasize that our earthshine
data are already sufficiently precise to detect, if they occur, any
meaningful changes in the earth's reflectance. Still greater precision
will occur as we expand our single site observations to a global
network.