The Maunder Minimum had almost no Sun Spots
Posted by pwl on February 28, 2009
“The Maunder Minimum is the name given to the period roughly from 1645 to 1715, when sunspots became exceedingly rare, as noted by solar observers of the time. It is named after the solar astronomer Edward W. Maunder (1851–1928) who discovered the dearth of sunspots during that period by studying records from those years. During one 30-year period within the Maunder Minimum, for example, astronomers observed only about 50 sunspots, as opposed to a more typical 40,000–50,000 spots.”
Given this graph it sure looks like temperatures are driven by the Sun, that huge ball of fusion going crazy at the center of our solar system that has 98+% of the mass of said system. A long slow bumpy progression trending upwards.
Where can one obtain the raw data for this chart? Oh, here, which also has this tidbit to add that does recognize the Sun as a contributing factor to the so called global warming.
“On longer time scales, the sun has shown considerable variability, including the long Maunder Minimum when almost no sunspots were observed, the less severe Dalton Minimum, and increased sunspot activity during the last fifty years, known as the Modern Maximum. The causes for these variations are not well understood, but because sunspots and associated faculae affect the brightness of the sun, solar luminosity is lower during periods of low sunspot activity. It is widely believed that the low solar activity during the Maunder Minimum and earlier periods may be among the principal causes of the Little Ice Age. Similarly, the Modern Maximum is partly responsible for global warming, especially the temperature increases between 1900 and 1950. One study (Stott et al. 2003), argues that residual warming due to the sustained high level of activity since 1950 is responsible for 16 to 36% of recent warming.“
How can we determine the numbers of sun spots other than direct human observation? Oh… this is one way:
“Solar activity also affects the production of beryllium-10, and variations in that cosmogenic isotope are studied as a proxy for solar activity.
Other historical sunspot minima have been detected either directly or by the analysis of carbon-14 in ice cores or tree rings; these include the Spörer Minimum (1450–1540), and less markedly the Dalton Minimum (1790–1820). In total there seem to have been 18 periods of sunspot minima in the last 8,000 years, and studies indicate that the sun currently spends up to a quarter of its time in these minima.”
What do you think of the sun spot issues? How can it be said that they don’t affect our weather enough to alter temperature on earth?