Where can i find a good data set to show me the change of global incoming radiation over the past 50 years?

Question

Where can i find a good data set to show me the change of global incoming radiation over the past 50 years?

Answer 1

I assume you mean Total Solar Irradiance (TSI).  Satellites have only measured it for the past 30 years (called ACRIM and PMOD).

http://www.acrim.com/RESULTS/Earth%20Obs...

http://tamino.wordpress.com/2007/07/24/p...

For the past 50 years you'll have to look up a TSI proxy.  For example, Figure 4 on page 3 here:

http://www.acrim.com/Reference%20Files/S...

Answer 2

Here's a chart for the past 30 years:

http://www.columbia.edu/~jeh1/mailings/2...

This cyclic solar variability yields a climate forcing change of about 0.3 W/m2 between solar maxima and solar minima. [Although solar irradiance of an area perpendicular to the solar beam is about 1366 W/m2, the absorption of solar energy averaged over day and night and the Earth’s surface is about 240 W/m2.] Several analyses have extracted empirical global temperature variations of amplitude about 0.1°C associated with the 10-11 year solar cycle, a magnitude consistent with climate model simulations, but this signal is difficult to disentangle from other causes of global temperature change including unforced chaotic fluctuations. The solar minimum forcing is thus about 0.15 W/m2 relative to the mean solar forcing. For comparison, the human-made GHG climate forcing is now increasing at a rate of about 0.3 W/m2 per decade (http://pubs.giss.nasa.gov/docs/2004/2004... If the sun were to remain ‘stuck’ in its present minimum for several decades, as has been suggested (http://news.independent.co.uk/sci_tech/a... in analogy to the solar Maunder Minimum of the seventeenth century, that negative forcing would be balanced by a 5-year increase of GHGs. Thus, in the current era of rapidly increasing GHGs, such solar variations cannot have a substantial impact on long-term global warming trends. Furthermore, recent sighting of the first sunspot of reversed polarity

(http://spaceweather.com/archive.php?view... and

(http://www.noaanews.noaa.gov/stories2008... signifies that the ~ 4-year period of increasing solar irradiance is about to get underway.