Decadal Variability in the Sun and Climate

October 27-29, 2004
Meredith, New Hampshire

THE EARTH OBSERVER November/December 2004 Vol. 16 No. 6: SORCE Science Meeting Addresses "Decadal Variablility in the Sun and Climate"

Thanks to all those who attended this years SORCE Science Meeting.  It was a great success.  We sincerely appreciate your contributions to our recent SORCE science meeting in Meredith, New Hampshire on Decadal Variability and the Earth climate and solar inputs.  We received much positive feedback about the high quality and informative content of the talks, and enthusiasm from the speakers.  Thank you all for taking the time to attend the meeting, and to prepare and deliver your excellent presentations. Below you will find Adobe PDF versions of most of the presentations and posters. They can be viewed using Adobe Acrobat reader version 5.0 or higher. If you do not have Adobe Acrobat reader, you can download a free copy here. If you have any questions, comments, or concerns, please email Vanessa George.

Meeting Overview

Discerning the role of the Sun in climate variations on time scales of decades is a challenging task. That climate forcing is well correlated with variations in the Sun's energy output is now relatively well established for total and UV irradiance using high-precision, space-based solar measurements spanning more than two decades. When the Sun is near the maximum of its activity cycle, it is about 0.1% brighter overall, with much greater changes at UV wavelengths. SORCE measures these variations with unprecedented accuracy, precision, and spectral coverage across the UV, visible, and IR. But the climate response to these measured solar variations presents a major puzzle. This SORCE Science Meeting seeks new understanding of the evidence for and mechanisms involved in decadal variability in the Sun and climate.

Widespread empirical evidence from the extensive Earth climate datasets suggests the presence of an 11-year solar signal of order 0.1K in surface, atmospheric, and ocean temperatures. But general circulation models (GCMs) underestimate this response by as much as a factor of five. The GCMs account primarily for direct forcing by changing incoming total radiation and assume that the response time for climate feedback processes to this external forcing is of order 100 years. Processes and pathways not included in the GCMs may help facilitate the larger than predicted climate response to decadal solar variability. Solar variations in the UV spectrum modulate stratospheric ozone concentrations, which may couple to climate via radiative and dynamical pathways. These pathways may involve the Northern and Southern annular modes, allowing a solar signal to be amplified and reach Earth's surface. Internal atmosphere-ocean oscillations such as the NAO and ENSO may also play a role. Clouds may expedite the feedback process, as they appear to also exhibit variability with the solar cycle. Stochastic climate variability may amplify the relatively small solar variations. Other, non-linear, climate processes are speculated.

Session 1
Solar Radiation - Status of Current SORCE Measurements
Session 2 Decadal Variability in the Atmosphere and Oceans
Session 3
Mechanisms and Modes of Decadal Solar Variability
Session 4
Climate Variability Modes (e.g. ENSO, NAO/AO, PDO) and Nonlinear Responses
Poster Presentations All Sessions


Mark Baldwin, NorthWest Research Associates, Inc., Bellevue, WA
Phone: 425-644-9660, ext. 323, e-mail:

Greg Kopp, Laboratory for Atmospheric and Space Physics, Univ. of Colorado, Boulder, CO
Phone: 303-4735-0934, e-mail:

Judith Lean, Naval Research Laboratory (NRL), Washington, DC
Phone: 202-767-5116, e-mail:


The SORCE Science Meeting was held at The Inns at Mill Falls, Church Landing in Meredith, NH. Activities began on Tuesday evening, October 26, with a Welcoming Reception at the Church Landing's Oval Room/Library. The SORCE Science Meeting began on Wednesday, October 27. Oral presentations were given throughout the day Wednesday, Thursday, and Friday morning. Poster summaries and presentations were set up for viewing Wednesday and Thursday, with a special poster session/reception Wednesday afternoon. Thursday evening there was a Science Dinner at the Gunstock Mountain Ski Lodge.

Below you will find Adobe PDF versions of most of the presentations and posters. They can be viewed using Adobe Acrobat reader version 5.0 or higher. If you do not have the Adobe Acrobat reader, you can download a free copy here. Click on the persons name for the abstract or click on the title for the actual presentation.


Session 1

Mark Baldwin (Keynote Talk)
Northwest Research Associates, Inc., Bellevue, WA
The Stratospheric Link Between the Sun and Climate
Gary Rottman
LASP, University of Colorado
The SORCE Mission - Going on Two Years

Bob Cahalan
NASA, Goddard Space Flight Center

Sun-Climate Introduction
Greg Kopp
LASP, University of Colorado
TIM Status and Contributions to the Total Solar Irradiance Record
Jerry Harder
LASP, University of Colorado
Solar Spectral Variability as Measured by the SORCE SIM Instrument
Bill McClintock
LASP, University of Colorado
Solar Ultraviolet Spectral Irradiance: Results from the SORCE SOLSTICE
Tom Woods
LASP, University of Colorado
Variability of the Solar XUV Irradiance from the SORCE XPS

Session 2

David Douglass
University of Rochester, New York
Climate Sensitivity of the Earth to Solar Radiation and Climate Models
Joanna Haigh
Imperial College London, UK
Solar Heating of the Lower Stratosphere and Its Influence on Tropospheric Climate
John McCormack
NRL, Washington DC
The Effect of Decadal Solar UV Variability on the Middle Atmosphere: A 2-D Modeling Perspective
Lesley Gray
Reading University, UK
Variability of the Winter Stratospheric Vortex Associated with the 11-Year Solar Cycle
Terry Nathan
University of California, Davis
Solar Cycle Induced Ozone Perturbations and the Reflection of Tropospherically Forced Planetary Waves
Alfred Powell
Lower Atmosphere Diagnostic Analysis for a Sun-Earth Connection

Session 3

Vikram Mehta (Keynote Talk)
The Center for Research on the Changing Earth System (CRCES), Columbia, MD
Decadal Climate Variability - Societal Impacts, Phenomena, Problems, and Prospects
Dick White
LASP, University of Colorado
Variability of the Sun's Radiative Output in the Last 30 Years and Its Relationship to the Record in Global Warming
Stephen Walton
San Fernando Observatory, California State University, Northridge
What Photometric Images Have (and Haven't) Taught Us about TSI
Claus Fröhlich
Physikalisch-Meteorologisches Observatorium Davos, World Radiation Center, Davos Dorf, Switzerland
Re-Analysis of the Long-Term Changes of the NIMBUS-7 Radiometer and Behavior of Total Solar Irradiance During Solar Cycle 21
Tom Woods
LASP, University of Colorado
Variation of the Bright Solar Lyman-Alpha Emission: Estimation of the UV Decrease During the Maunder Minimum
Ken Schatten
AI-Solutions, Lanham, MD
The Energetics of Sunspots and Faculae: Fluid Dynamics vs. Magnetic Inhibition
Tom Berger
Lockheed Martin, Solar and Astrophysics Laboratory, Palo Alto, CA
High Resolution Observations of Solar Faculae

Peter Foukal
Heliophysics, Inc., Nahant, MA

What Decadal Irradiance Variations Teach Us about the Likelihood of Multi-Decadal Variations

Session 4

Madeleine Nash (Keynote Talk)
TIME Magazine Contributor and Book Author  San Francisco, CA
Chasing El Niño: A Science Writer's Walk on the Wild Side of Climate
Amy Clement
Rosenstiel School of Marine and Atmospheric Sciences, Miami, FL
ENSO Basics
Mark Cane
Lamont-Doherty Earth Observatory of Columbia University, New York, NY
Volcanic and Solar Forcing of the Tropical Pacific Over the Past 1000 Years
Michael Mann
University of Virginia, Charlottesville
Dynamical Mechanisms of Solar Climate Forcing in Past Centuries
Sultan Hameed
Stony Brook University, NY
Responses of the Atmospheric Centers of Action to the Solar Cycle in the East and West Phases of the Quasi-Biennial Oscillation
Dave Thompson
Colorado State University, Fort Collins
The Impact of Stratospheric Ozone Depletion on Climate Change at Earth's Surface
Alexander Ruzmaikin
Jet Propulsion Laboratory, California Inst. of Technology, Pasadena
Solar and QBO Influences on the North Annular Mode
Hans Mayr
Goddard Space Flight Center, Greenbelt, MD
The QBO as Amplifier and Conduit to Lower Altitudes of Solar Cycle Influence?
Eugene Cordero
San Jose State University, CA
The Response of the QBO to Zonal-Mean Ozone Perturbations Consistent with the 11-Year Solar Cycle
Murry Salby
PAOS, University of Colorado, Boulder
Evidence of the Solar Cycle in the Circulation of the Stratoshpere and its Influence on the Troposhpere
Jose Rial
University of North Carolina, Chapel Hill
On the (Nonlinear) Causes of Abrupt Climate Change During the Last Ice Age
Fabrizio Sassi
NCAR, UCAR, Boulder, CO
The Effect of ENSO on the Dynamical and Thermal Structure of the Middle Atmosphere
Enric Palle
Big Bear Solar Observatory (New Jersey Institute of Technology)

Decadal Variability in the Earth's Reflectance as Observed by Earthshine

Shuntai Zhou
NOAA/NCEP, Climate Prediction Center
Sensitivity of Stratospheric Zonal Wind to Solar Cycle Variations
Shaopeng Huang
University of Michigan, Ann Arbor
Lunar Regolith Temperature as a Monitor of the Radiation Budget of Earth


Session 1

Claus Fröhlich
A Comparison of the VIRGO and TIM Data
Marty Snow
The SOLSTICE Observing Technique
Chris Pankratz
SORCE Science Data Processing and Availability

Session 2

Pilar Montanes-Rodriquez
Global Measurements of the Earth's Visible Spectral Albedo
Alfred Powell
Vertical Propagating Wave Diagnostic Analysis
David Salstein
Relationships Between Solar Activity, Earth Rotation and Atmospheric Angular Momentum
Richard Wolfson
A Solar-Cycle Influence on New England's Climate?
Shengpan Zhang
Response of the O(1S) Dayglow to the Solar Zenith Angle and Solar Irradiance: An Empirical Model by WINDII on UARS

Session 3

Steven Dewitte
Measurement of the Long-Term Total Solar Irradiance Trend: What is Needed Versus What is Achieved
Claus Fröhlich Some Thoughts About the Reliability of Reconstructions of Total Solar Irradiance into the Past
Dora Preminger
Inferring Total Solar Irradiance from Sunspot Areas Only
Delores Knipp
Direct and Indirect Thermospheric Heating Sources for Solar Cycles 21-23
Linton Floyd
The SUSIM MgII Core-to-Wing Ratio Index
Marty Snow
The Role of Spectral Resolution in Measuring the Solar Magnesium II
Jeff Morrill
Center-to-Limb Variation of the Solar UV Spectrum Observed by SKYLAB
Guoyong Wen
Empirical Orthogonal Function Analysis of Solar Spectral Irradiance from SIM
Helen Coffey
NOAA NESDIS Data Rescue Solar Image Scanning Project