How variations in Sun’s energy contribute to climate change
By ANISaturday, January 15, 2011
WASHINGTON - A new study has brought experts one step closer to understanding how much energy the Earth receives from the Sun, and how changes in that energy could contribute to climate change.
The researchers report a lower value of that energy, known as total solar irradiance, than previously measured.
“Improved accuracies and stabilities in the long-term total solar irradiance record mean improved estimates of the Sun’s influence on Earth’s climate,” said Greg Kopp of the Laboratory for Atmospheric and Space Physics (LASP) of the University of Colorado Boulder.
“Scientists estimating Earth’s climate sensitivities need accurate and stable solar irradiance records to know exactly how much warming to attribute to changes in the Sun’s output, versus anthropogenic or other natural forcings,” said Judith Lean of the Naval Research Laboratory, in Washington, D.C.
The new, lower TSI (total solar irradiance) was measured by the LASP-built Total Irradiance Monitor (TIM) instrument on the NASA Solar Radiation and Climate Experiment (SORCE) spacecraft.
Kopp said, “The calibration facility indicates that the TIM is producing the most accurate total solar irradiance results to date, providing a baseline value that allows us to make the entire 32-year record more accurate. This baseline value will also help ensure that we can maintain this important climate data record for years into the future, reducing the risks from a potential gap in spacecraft measurements.”
Lean said, “An improved and extended solar data record will make it easier for us to understand how fluctuations in the Sun’s energy output over time affect temperatures, and how Earth’s climate responds to radiative forcing.”
The study appears in Geophysical Research Letters. (ANI)
