There’s a recent post on Watts Up With That (WUWT) which seems to simply be a copy of a BBC blog post by Paul Hudson. The blog post is titled Real risk of a Mauder Minimum “Little Ice Age” says leading scientist. The BBC blog post refers to the work of Mike Lockwood from the University of Reading. A few years ago, Mike Lockwood suggested there was about an 8% chance that the Sun was returning to Maunder Minimum-like conditions. He’s now, apparently, upped that to between 20-30%.
The BBC blog post comments that
And a repeat of the Dalton solar minimum which occurred in the early 1800s, which also had its fair share of cold winters and poor summers, is, according to him, ‘more likely than not’ to happen.
He believes that we are already beginning to see a change in our climate – witness the colder winters and poor summers of recent years – and that over the next few decades there could be a slide to a new Maunder minimum.
So, the article appears to be implying that we might be heading towards a new “Little Ice Age”. Now this is a little odd as I’ve read some of Mike Lockwood’s papers and that’s not what I would have expected him to be proposing. While writing this post, I noticed this tweet from Oliver Bothe
Lockwood on FB: amazing how one can be misrepresented! point I made is that many of “evidence” for solar influence come from Europe winter
— O. Bothe (@geschichtenpost) October 29, 2013
I haven’t actually checked Mike Lockwood’s facebook comment, but it would be surprising if it – coincidentally – was referring to something else. If we want to get a sense of what Mike Lockwood’s views are, we can look at one of his recent papers. In 2012, Mike Lockwood published a paper called Solar influence on Global and Regional Climates. In the conclusions of this paper, Mike Lockwood says
From solar-induced variations of cosmogenic isotopes over the past 104 years, Lockwood (2010) and Barnard et al. (2011) have deduced that there is an 8% chance that the Sun will return to Maunder Minimum conditions within 50 years. The recent evolution of solar cycle 24 indicates that the Sun may well be following such a trajectory (Owens et al. 2011).
Here, he suggests an 8% chance that the Sun will return to Maunder Minimum conditions within 50 years. The BBC blog post suggests that he has upped this to between 20 and 30%. Fair enough, that’s quite possible. The conclusions continue with
Feulner and Rahmstorf (2010) and Jones et al. (2012) have used GCMs and EBMs to predict that this will offset anthropogenically rising global temperatures by no more than about 0.2°C in the year 2100, relative to what would happen if the solar output remained constant. Similarly, Lean and Rind (2009) find that the solar decline would delay the arrival at a given temperature level by no more than about 5 years. Thus, these predictions show that continued solar decline will do little to alleviate anthropogenically driven global warming.
This seems to be fairly clear. The Sun returning to Maunder Minimum conditions will do little to alleviate anthropogenically driven global warming. This is actually a fairly obvious conclusion. The anthropogenic forcings by the end of the 21st century will likely be about 4 Wm-2 relative to the mid 1800s, and 2Wm-2 relative to today. The Sun returning to Maunder Minimum conditions means that solar forcing will likely be a few tenths of a Wm-2 less than today. Anthropogenic forcings will therefore be about an order of magnitude greater than solar forcings and will therefore almost certainly dominate.
Possibly, the most significant point made in the conclusions of Mike Lockwood’s paper are
However, the decline should do much to end the debate about the fraction of global warming that can be attributed to solar change. For the first time since about 1900, long-term solar and anthropogenic trends are now in opposite directions.
In other words, if the Sun returns to Maunder Minimum conditions it will become extremely clear that anthropogenic influences are dominating the warming of the climate system. So, in some sense, a return to Maunder Minimum-like conditions could help to at least make it clear that the Sun is not a significant driver of global warming. Having said that, there are many aspects of the science associated with global warming that I would argue are obvious, that many still refuse to accept. So, maybe this is more wishful thinking than anything else.
Anyway, unless Mike Lockwood has changed his mind in the last year, he doesn’t appear to be suggesting that the Sun returning to Maunder Minimum-like conditions will herald the onset of another Little Ice Age. If anything, he’s arguing that it will have very little effect and will make it much more apparent that the warming of the climate system is anthropogenic. So, it seems that even if Paul Hudson has not been completely dishonest, his article is somewhat misleading. I also found it odd that he ends with a reference to Michael Mann as being
a vociferous advocate of man-made global warming,
An advocate? Michael Mann happens to be a leading scientist who understands the science associated with global warming and can explain and present the evidence that it is almost certainly anthropogenic. Is Paul Hudson seriously suggesting that Michael Mann is just expressing his opinion about this? There is actual scientific evidence to support this.
One aspect of this that is maybe topical is that I’ve had a couple of discussions recently with people who regard the BBC as being biased (in one case, it was presented as a statement of fact). If this blog post qualifies as the BBC being balanced, then it appears to be a very strange way to do so. It appears to require that you misrepresent what a scientist is saying and then suggest that the views of other scientists is a form of advocacy, rather than a view based on the actual scientific evidence. A very strange way to introduce balance, in my opinion at least.