The Sun's total irradiance: Cycles, trends and related climate change uncertainties since 1976
Abstract
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.
- Publication:
-
Geophysical Research Letters
- Pub Date:
- December 1998
- DOI:
- 10.1029/1998GL900157
- Bibcode:
- 1998GeoRL..25.4377F
- Keywords:
-
- Global Change: Solar variability;
- Solar Physics;
- Astrophysics;
- and Astronomy: Solar irradiance;
- Solar Physics;
- Astrophysics;
- and Astronomy: Photosphere