Dispute Over Relevance Of Falling Solar Activity
SOLAR activity is falling more rapidly than at any time in the past 10,000 years, increasing the risk of a repeat of the Maunder Minimum which coincided with the “little ice age” of the 1600s, according to research by a leading British climate scientist.
BBC reports on work by Mike Lockwood of Reading University have sparked furious debate about the implications of weaker solar activity for the climate.
Professor Lockwood has said the late 20th century was a period when the sun was unusually active and a “grand maximum” occurred around 1985. Since then it has been getting quieter.
By studying certain isotopes in ice cores, the professor has been able to determine the level of solar activity over thousands of years.
According to the BBC, he found 24 different occasions in the past 10,000 years when the sun was in exactly the same state as it is now, but the present rate of solar decline is faster.
Based on these findings, he has raised the risk of a new Maunder Minimum from less than 10 per cent to 25 to 30 per cent. A repeat of the Dalton solar minimum, he said, was “more likely than not” to occur.
In comments online, he rejected reports that his findings indicated a coming severe downturn in global surface temperature. He said the falling solar activity was more significant on a regional scale, indicating the possibility of harsher winters in Europe, because it increased the chances of more “blocking” low-pressure regions that would allow cold air to reach northern England.
The significance of solar activity in climate change has been a key area of dispute between climate scientists and sceptics. The established view of the climate scientists is that solar variation was well understood and had only a limited impact on global surface temperatures.
David Whitehouse of the Global Warming Policy Foundation said solar activity was an ongoing area of research, with the weak effect seen by Professor Lockwood in the data between low solar activity and severe cold winters in Europe questioned by other researchers, who had failed to find such a connection.