Day By Day

Thursday, April 02, 2009

Disturbing News from NASA

NASA reports that the solar minimum (the amount of activity on the surface of the Sun) has, contrary to many experts' predictions, continued to deepen.
The sunspot cycle is behaving a little like the stock market. Just when you think it has hit bottom, it goes even lower.

2008 was a bear. There were no sunspots observed on 266 of the year's 366 days (73%). To find a year with more blank suns, you have to go all the way back to 1913, which had 311 spotless days: plot. Prompted by these numbers, some observers suggested that the solar cycle had hit bottom in 2008.

Maybe not. Sunspot counts for 2009 have dropped even lower. As of March 31st, there were no sunspots on 78 of the year's 90 days (87%).

It adds up to one inescapable conclusion: "We're experiencing a very deep solar minimum," says solar physicist Dean Pesnell of the Goddard Space Flight Center.

"This is the quietest sun we've seen in almost a century," agrees sunspot expert David Hathaway of the Marshall Space Flight Center.

Read it here.

Why should we care? Because changes in solar activity have consequences here on earth.

Less solar activity means more cosmic rays enter the region around Earth, increasing health risks.

A decline in solar radiation means global cooling on Earth.

Freeman Dyson thinks we are on the verge of a new Ice Age -- if this decline in solar activity continues much longer he might be right.

Finally, like the econometric scholars and climate scientists NASA has constructed computer models -- unlike their more arrogant colleagues, though, NASA admits that their models don't predict the future with much accuracy.