Solar energy, and climate change

In today's Inquirer we published an article about what role sunspots may have had in the sinking of the Titantic.

As NASA's Rodney Viereck said no reasonable scientist would blame the sinking on sunspots -- violent solar storms that actually subtly increase solar output.

The well-documented sunspot lull around the time of the sinking -- and the records date all the way to Galieo, 300 years before the Titanic -- might explain the abundance of raw material, the polar ice.

The conditions that caused ice to break loose would be harder to pinpoint.

But unquestionably the presence of such massive ice boulders at so southerly a latitude suggest that something extreme was going on.

Just how sunspots would affect climate is a complicated question. Even during the extreme lulls of the 17th Century, solar experts estimate that the loss of energy was in the order of a mere 0.25 percent.

The impacts, however, are well-embedded inthe climate record. As we mentioned, in the very cold heart of the Little Ice Age, not a single spot was detected from 1661 to 1671.

How would the effect of sunspots compare with human activity as an influence on climate change. That's unclear.

The U.N. Intergovernmental Panel on Climate Change has estimated that solar fluctuations have about one-fifth the climate impact of human greenhouse gases.

But the PICC also has cautioned that the estimate was based on a "low level of understanding."