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Natural Science Forum / Physics / General Physics / July 200820th century is the inverse of the Maunder Minimum
The Maunder Minimum (1645 to 1715 A.D.) is almost the exact inverse of the situation that we experienced in the late 20th century. During the Maunder Minimum we had 70 consecutive years where the solar cycle sunspot numbers were flat. Starting in the 1940s, we experienced seven consecutive solar maximums all with historically high sunspot maximums. This is the reconstructed sunspot numbers listed every ten years during the Maunder Minimum. YearBP [YearAD] SN sigma 305 1645 4.8 7.2 295 1655 1.4 7.1 285 1665 -2.3 7.4 275 1675 -5.1 7.5 265 1685 -5.6 7.3 255 1695 -4.2 6.8 245 1705 -0.7 7.0 235 1715 6.7 7.2 Source: “Unusual activity of the Sun during recent decades compared to the previous 11,000 years”, Nature, Vol. 431, No. 7012, pp. 1084 - 1087, 28 October 2004. A negative sunspot number reflects the analysis that during the Maunder Minimum the sun’s total irradiance was less than the current day quiet sun (zero sun spot number) total irradiance. However other studies, e.g. Foukal, P., G. North, and T. Wigley (2004), “A stellar view on solar variations and climate”, Science, 306, 68– 69 suggest that based on observations of sun like stars that extended minima are simply akin to persistent solar cycle minima. These stellar studies need to be taken with care because many of the effects are latitude dependent and the angle at which we see other stars is random. From 1937 to 2002 AD we had an historically high seven consecutive sunspot numbers all in excess of 100. See: http://sidc.oma.be/html/wolfaml.html Go to the bottom of the page. If CO2 increases were happening during normal sunspot cycles then the evidence for AGW would be very strong. But we have experienced a period of global warming that exactly coincides with historic highs in solar activity. In fact, it is the exact inverse of what we experienced during the Maunder Minimum. If the Maunder Minimum led to a mini ice age, why wouldn’t the historically high solar activity of the later 20th century lead to global warming? The counter argument is that, based on lots of assumptions, the solar increases can’t account for the warming. But these assumptions and the models used to calculate the impact of solar changes on earth warming are not well understood. I think that we need to dig a lot harder to understand how changes in solar output affect global temperatures. --Mike Jr > The Maunder Minimum (1645 to 1715 A.D.) is almost the exact inverse of > the situation that we experienced in the late 20th century. During > the Maunder Minimum we had 70 consecutive years where the solar cycle > sunspot numbers were flat. Starting in the 1940s, we experienced > seven consecutive solar maximums all with historically high sunspot > maximums. NASA Science News for July 11, 2008 The sun is entering its third year of eerie calm. Sunspots are rare and solar flares simply aren't happening. Is this "solar minimum" lasting longer than it should? A NASA scientist has examined centuries of sunspot data to find the answer, revealed in today's story from Science@NASA: http://science.nasa.gov/headlines/y2008/11jul_solarcycleupdate.htm?list89139 Check out our RSS feed at http://science.nasa.gov/rss.xml! > > The Maunder Minimum (1645 to 1715 A.D.) is almost the exact inverse of > > the situation that we experienced in the late 20th century. During [quoted text clipped - 13 lines] > > Check out our RSS feed athttp://science.nasa.gov/rss.xml! I also have been following the solar cycle 24 no show. Not to confuse things, my post was pointing out that in the period 1937 to 2002, the sun had turned up the heat. Since 2002, the heat has been turned down. Just as 2 PM is the hottest part of the day even though the most solar heating takes place at midday there is a five year delay between changes in solar output and changes to global temperature on the earth's surface. I predict that if solar cycle 24 continues to be a no show then in two more years we will start to see a serious decline in global temperatures. --Mike Jr >>> The Maunder Minimum (1645 to 1715 A.D.) is almost the exact inverse of >>> the situation that we experienced in the late 20th century. During [quoted text clipped - 25 lines] > > --Mike Jr Five years of solar minimum would be a nice variable to check global warming against! > >>> The Maunder Minimum (1645 to 1715 A.D.) is almost the exact inverse of > >>> the situation that we experienced in the late 20th century. During [quoted text clipped - 28 lines] > Five years of solar minimum would be a nice variable to check > global warming against! Agreed. Let's hope that nature continues to cooperate with our little science fair project. :-) --Mike Jr > > The Maunder Minimum (1645 to 1715 A.D.) is almost the exact inverse of > > the situation that we experienced in the late 20th century. During [quoted text clipped - 13 lines] > > Check out our RSS feed athttp://science.nasa.gov/rss.xml! One more point. If you have been following the parade of predictions about solar cycle 24 you will realize how comical all this really is. Each time a prediction for a start is exceeded a new prediction is made. That January start had to be retracted. Solar cycle 24 was predicted by Dr. Hathaway to be very large. I'll give the guy one thing, he doesn't let the facts get in the way of his story. Time will tell, one way or the other. 1933 was about when the sun kicked into high gear. Maybe solar cycle 24 is the sun gearing back down. --Mike Jr. > > > The Maunder Minimum (1645 to 1715 A.D.) is almost the exact inverse of > > > the situation that we experienced in the late 20th century. During [quoted text clipped - 28 lines] > > - Show quoted text - Why is the ice on Mars melting? The Sun must still be heated up. Mitch Raemsch > > > > The Maunder Minimum (1645 to 1715 A.D.) is almost the exact inverse of > > > > the situation that we experienced in the late 20th century. During [quoted text clipped - 33 lines] > > Mitch Raemsch The earth has a lag time of five years. I haven't read any studies on what the lag time is for Mars but it is not zero. --Mike Jr |
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