The Sun's total irradiance: Cycles, trends and related climate change uncertainties since 1976
Article first published online: 7 DEC 2012
Copyright 1998 by the American Geophysical Union.
Geophysical Research Letters
Volume 25, Issue 23, pages 4377–4380, 1 December 1998
How to Cite
- Issue published online: 7 DEC 2012
- Article first published online: 7 DEC 2012
- Manuscript Accepted: 28 AUG 1998
- Manuscript Received: 19 JUN 1998
A composite record of the Sun's total irradiance compiled from measurements made by five independent space-based radiometers since 1978 exhibits a prominent 11-year cycle with similar levels during 1986 and 1996, the two most recent minimum epochs of solar activity. This finding contradicts recent assertions of a 0.04% irradiance increase from the 1986 to 1996 solar minima and suggests that solar radiative output trends contributed little of the 0.2°C increase in the global mean surface temperature in the past decade. Nor does our 18-year composite irradiance record support a recent upward irradiance trend inferred from solar cycle length, a parameter used to imply a close linkage in the present century between solar variability and climate change.