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This post is really about the monthly NOAA update of the solar cycle, but before I do that, I must note some really bad science journalism in connection with that solar minimum.
This week NASA released a poorly written press release describing how the Sun’s magnetic field flips whenever it goes through solar maximum, the period when sunspot activity reaches its maximum. The article gave the incorrect impression that this “flip” will be some grand singular and spectacular event and when it happens the consequences to Earth could be significant. Then it buried this most important little detail to the article’s final paragraphs:
“The sun’s north pole has already changed sign, while the south pole is racing to catch up,” says Scherrer. “Soon, however, both poles will be reversed, and the second half of Solar Max will be underway.”
In other words, this “flip” is already half over, and no one noticed. Anyone with the slightest knowledge of the Sun and the solar cycle should have seen this, and realized the press release is a bit hyped and not very thoughtfully written. The real story is that the magnetic field of the Sun’s two hemispheres are not aligned. Why is that? What causes it? Do scientists know? Is this misalignment somehow connected to the Sun’s inability to produce sunspots this solar maximum? Or is this misalignment not that unusual, and thus not really significant?
Sadly, however, too many of today’s science journalists (and their editors) know very little about science. When they see a press release from NASA, it must be true, and they quickly rush to retype it, without asking anyone any of these basic questions. Thus, we have stories like these:
- From Discovery: The Sun is about to (magnetically) flip!
- From CBS: Sun’s magnetic field about to flip, causing “ripple effect”
- From Space.com: Sun will flip its magnetic field soon
Space.com was I think sufficiently embarrassed by the last article that Mike Wall there felt a need to publish his own update, Sun’s magnetic field flip won’t doom Earth, scientists say. Wall successfully dismissed the doomsday tone of the previous articles, while carefully noting the unusually weak nature of the present solar maximum and its connection to the Sun’s magnetic field reversal. Unfortunately, he failed to ask any of my questions above, which I think would have helped clarify this story much better for his readers.
The truth is that such a misalignment of the northern and southern halves of the Sun’s magnetic field during its field reversal is not unusual at all, and happens practically every time the field flips. In this sense, the Sun is behaving just has it always has since solar scientists began studying it seriously about three hundred years ago, and thus, this magnetic “flip” is not big news.
What is big news is the weak nature of that magnetic field, and the resulting wimpiness of the resulting sunspot cycle and solar maximum. On August 6 NOAA released its monthly update of the Sun’s sunspot cycle, covering the period for July 2013. As I do every month, this graph is posted below, with annotations to give it context.
The graph above has been modified to show the predictions of the solar science community. The green curves show the community’s two original predictions from April 2007, with half the scientists predicting a very strong maximum and half predicting a weak one. The red curve is their revised May 2009 prediction.
As you can see, the Sun’s sunspot activity continued at a very low level in July, comparable to levels seen for most of 2012. It surely looks like the predicted second peak of a double-peaked solar maximum has already occurred. Since the southern hemisphere magnetic field has not yet flipped, however, that second peak might not yet be over, and we might yet see another jump in sunspot activity, when the flip happens.
And as I noted last month, the actual sunspot maximum apparently occurred two years ago, in October 2011. That was the only time since I began tracking sunspot activity beginning in 2008 that solar activity actually exceeded even the weak prediction of the solar science community. In general, for this entire solar cycle the Sun has consistently underperformed every expectation of every solar scientist.
Talk about the uncertainty of science! What we have here is a clear demonstration that we really don’t understand this process, and that a lot of research will still be necessary before we do.
The significance of this weak solar maximum, however, really centers on how the Sun will behave in the future. In the past, weak sunspot production has been associated with cold climates. We don’t why or how sunspots link with climate, but the link does appear to exist. If the Sun stops producing sunspots, as some solar scientists have predicted, we should not be surprised if the Earth’s climate cools. In fact, the lack of sunspots in the past six years could very well explain the lack of increase in temperature in the global climate in the past decade.