Authors: Gary Rottman, Thomas Woods, Jerald Harder, Greg Kopp, William
McClintock, Juan Fontenla, Marty Snow, Byron Smiley
Affiliation: LASP, University of Colorado
The Sun’s electromagnetic radiation is the dominant energy input to the
Earth system. It heats the lands and ocean, maintains our atmosphere, generates
clouds, and cycles the planet’s water. A detailed understanding of solar
irradiance, and specifically an understanding of its variability, is necessary
for most terrestrial studies. The measurement of irradiance, which integrates
the radiation from the entire solar disk facing the Earth, is completely analogous
to the study of the Sun as a star.
In January 2003, NASA launched the Solar Radiation and Climate Experiment, SORCE.
This satellite carries four scientific instruments to measure the total solar
irradiance (TSI) and spectral irradiance over almost the entire wavelength range
from X-rays to the near infrared. In particular a new spectrometer device covers
the visible to near infrared with sufficient precision and accuracy to establish
solar variability at these important wavelengths. Meanwhile, the SORCE TSI instrument
continues the data record of today’s ACRIM, VIRGO, and ERBS. The SORCE
SOLSTICE and XPS instruments measure the ultraviolet and soft X-rays and continue
observations from similar instruments on the UARS and TIMED missions.
This poster provides an overview of results from the first year of SORCE observations
and considers the relation of the spectral measurements to TSI.