Guest post by David Archibald
Successful prediction of levels of solar activity suggests that prediction of other phenomena driven by solar activity might also be successful, and useful. Sea level rise is a concern of some people. President Obama said in June 2008 that his nomination in the Democratic primaries was “the moment when the rise of the oceans began to slow”.
The above graph shows the satellite data from the University of Colorado from late 1992. A change of trend is evident in 2004. Prior to that, sea level was rising at 4.2 mm/annum, and after 2004 at 1.5 mm/annum. 2003 was the recent peak in solar activity in terms of flares, F10.7 flux and proton flux. It is likely that the lower rate of rise post 2004 is due to lower subsequent solar activity.
The CSIRO compiled tide gauge data from 1870. The graph above shows that data with the subsequent satellite data plotted together.
The modern retreat of glaciers began in 1860. Initially sea level rose at 1.0 mm/annum. After 1930, it almost doubled to 1.9 mm/annum. This is a well-defined uptrend, now 80 years long.
Our prediction of a 2° C decline in temperature for the mid-latitudes over Solar Cycles 24 and 25 suggests that sea level will stop rising, and should start falling at some point prior to 2032.
The graph above combines the satellite data with the prior ten years of tide gauge data and shows the bounds of the long term rise at 1.9 mm/annum post 1030. Sea level could remain flat for another ten years before that trend in sea level rise is broken.