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To: qam1
Secular total solar irradiance trend during solar cycles 21–23

NASA Study Finds Increasing Solar Trend That Can Change Climate

"Although the inferred increase of solar irradiance in 24 years, about 0.1 percent, is not enough to cause notable climate change [on Earth], the trend would be important if maintained for a century or more. Satellite observations of total solar irradiance have obtained a long enough record (over 24 years) to begin looking for this effect."

Solar Irradiance and Long-Term Climate Variability (this is old, but good info on the Maunder Minimum)

LONG-TERM TOTAL SOLAR IRRADIANCE (TSI) VARIABILITY TRENDS: 1984-2004

"Using the discontinuous nonoperational Nimbus-7, SMM ACRIM, and UARS ACRIM mission TSI data sets, Wilson and Mordvinor (2003) suggested the existence of an additional long-term TSI variability component, 0.05 %, with a period longer than a decade. Analyses of the ERBS/ERBE data set do not support the Wilson and Mordvinor analyses approach because it used the Nimbus-7 data set which exhibited a significant ACR response shift of 0.7 Wm-2 (Lee et al,, 1995; Chapman et al., 1996)."

...

Here comes the Sun

The SORCE (SOlar Radiation and Climate Experiment) Science Working Group Meeting (July 17-19, 2002) (note Judith Lean's PDF presentation available here)

Sun's Role in Climate Change Continues to Spark Controversy

" Has an increasing trend in the Sun's brightness contributed to global warming over the last few decades? One study published recently says it has but Judith Lean will tell a joint session of the UK/Ireland National Astronomy Meeting and Solar Physics Meeting in Dublin that a different study has come to the opposite conclusion when she tackles the controversial topic of the relationship between our climate and the Sun on Tuesday 8 April [2003]."

...

"Temperature changes in concert with solar activity are indeed apparent during the past millennium," reports Dr Lean, "but are typically of order 0.2 to 0.5 degrees C on time scales of hundreds of years. Since 1885, global warming in response to changes in the Sun's brightness is now thought to have been less than 0.25 degrees C."

Under a Variable Sun

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Summary of all the above: It cannot be demonstrated that there has been sufficient/significant solar variability (particularly an increase in solar output/irradiance) sufficient to cause climate change on Earth, or on other bodies in the Solar System, over the past 25-30 years. There is an apparent solar component to the global warming observed over the past 150-160 years, with a maximum 30% contribution, most notably contributing to the temperature rise in the early part of the 20th century.

I'll post all these links and my summary in my profile, if you consider them informative. I'll leave that to you. If you want to me to go ahead and do so, so you can consider this another "win", feel free.

73 posted on 05/17/2007 7:20:54 AM PDT by cogitator
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To: AFPhys

See what you think of the information I provided in post 73. Is that open-minded enough for you?


74 posted on 05/17/2007 7:22:06 AM PDT by cogitator
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To: cogitator
May I take you to then have agreed that the so called "climate sensitivity" is 1.000 and may I quote you to that effect in all future discussions of this subject?

Or are fudge factors of 5-10 times kosher for CO2 but 2-3 times illegitimate for solar forcings?

75 posted on 05/17/2007 9:56:44 AM PDT by JasonC
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