Wednesday, June 15, 2011

Even a new Maunder Minimum will not bring a new Little Ice Age, not even close, not even a cooling off. Sadly, If Sun Goes Into ‘Hibernation’ It Won’t Stop Catastrophic Global Warming, But It Might Put the Deniers in Hibernation by Joe Romm, Climate Progress, June 15, 2011

Sadly, If Sun Goes Into ‘Hibernation’ It Won’t Stop Catastrophic Global Warming, But It Might Put the Deniers in Hibernation


The anti-science disinformers are ecstatic over an analysis that says by 2020 we might be entering a long period of anomalously low solar activity.  The headline at Fox Nation is:
Not.  Not even close, actually.
Yes, there is a credible prediction based on independent studies that we could possibly be entering a so-called “grand minimum” in solar activity.  And yes, the last one on record, the “Maunder minimum,” which occurred between 1645 and 1715, coincided with the so-called Little Ice Age.
But the LIA wasn’t just driven by a drop in solar forcing –  it was also driven by a burst of volcanic activity (see “A detailed look at the Little Ice Age“).  And now we have human-caused greenhouse gases that have overwhelmed the much, much smaller solar forcing.
You’d never know it from the anti-science crowd, but last year Geophysical Research Letters (GRL) published a major analysis of this precise situation, “On the effect of a new grand minimum of solar activity on the future climate on Earth” (PDF here).  That peer-reviewed study concluded that if we did see a Maunder minimum this century:
In summary, global mean temperatures in the year 2100 would most likely be diminished by about 0.1 °C
That means, on our current emissions path, we would be only about 9 °F to 11 °F warmer than preindustrial levels in 2100, rather than, say about 9 °F – 11 °F warmer.  I would note that the 2010 analysis did not include major carbon cycle feedbacks like the tundra, whose impact will likely exceed that of any drop in solar irradiance this century (see NSIDC bombshell: Thawing permafrost feedback will turn Arctic from carbon sink to source in the 2020s, releasing 100 billion tons of carbon by 2100).
Here are three key points:
  • The Sun is “the dominant source of energy for Earth’s climate system” as the GRL paper notes, but “changes associated with solar variability are small” and “their contribution to recent warming is negligible” (see links below).
  • 2010 was tied with 2005 as the hottest year on record in spite of coming at the end of “the deepest solar minimum in nearly a century.”
  • As NASA wrote during the deep 2009 minimum, “let’s assume that the solar irradiance does not recover. In that case, the negative forcing, relative to the mean solar irradiance is equivalent to seven years of CO2 increase at current growth rates. So do not look for a new ‘Little Ice Age’ in any case.”
Indeed, the GRL analysis was done because of this deep solar minimum, which is plotted below:
PMOD TSI
Figure 2: Total Solar Irradiance as measured by satellite from 1978 to 2010
Now, as we are have finally come out of that deep minimum, we have this new prediction:
As the current sunspot cycle, Cycle 24, begins to ramp up toward maximum, independent studies of the solar interior, visible surface, and the corona indicate that the next 11-year solar sunspot cycle, Cycle 25, will be greatly reduced or may not happen at all.
The results were announced at the annual meeting of the Solar Physics Division of the American Astronomical Society, which is being held this week at New Mexico State University in Las Cruces.
“This is highly unusual and unexpected,” Dr. Frank Hill, associate director of the NSO’s Solar Synoptic Network, said of the results. “But the fact that three completely different views of the  point in the same direction is a powerful indicator that the sunspot cycle may be going into hibernation.”
… All three of these lines of research to point to the familiar sunspot cycle shutting down for a while.
“If we are right,” Hill concluded, “this could be the last solar maximum we’ll see for a few decades. That would affect everything from space exploration to Earth’s climate.”
Yes, it would affect the climate, just not much.
The Naval Research Laboratory and NASA reported in 2009 that, “if anything,” the sun contributed “a very slight overall cooling in the past 25 years.” The study, “How natural and anthropogenic influences alter global and regional surface temperatures: 1889 to 2006,” found:
According to this analysis, solar forcing contributed negligible long-term warming in the past 25 years and 10% of the warming in the past 100 years.
A major 2007 study concluded:
Now human-caused emissions are driving climate change to dangerous levels with forcings that dwarf previous natural forcings both in speed and scale (see “Humans boosting CO2 14,000 times faster than nature, overwhelming slow negative feedbacks“).
The current solar cycle (24) is limping along modestly now, and expected to peak in 2013.  That and soaring greenhouse gas emissions (thank you China, U.S. climate disinformers and your political allies) — along with the slow equilibration of global temperatures with current CO2 concentrations — will insure that half the years this decade or more will probably be as warm or warmer than 2010, and that this will again be the hottest decade on record.
If Solar Cycle 25 doesn’t appear until 2022 (or 2092), it won’t change the fact that if we keep listening to the disinformers and taking no action to reduce emissions, we will ravage human civilization.  Sure, it might allow some disinformers to say that warming was not occurring as fast as  the worst-case scenarios, but the more profound reality would be that even with a grand solar minimum,  we’d still be seeing record warming decade after decade.
That should cause some of the disinformers to go into hibernation.  In rejecting my bet about warming, meteorologist Joe Bastardi himself emailed me:
The forecast was made 3 years ago, that by 2030 the temp as measured by satellite would fall back to levels in the late 70s.  I have never, never never played the markets or “bet” on the weather.
Obviously, with the attention that has been created, and the idea I am now betting my livelihood on this, which is way the article has appeared, if wrong, I am driven from the field.
And of course, in any thing I am proven wrong on, and since I do know, understand and respect the agw argument, as I have stated countless times, I would be an advocate.
Of course, by then it would be too late to avert many of the most impacts…
A Maunder Minimum can’t stop catastrophic global warming — only we can!
NOTE:  The grand solar minimum prediction has been disputed here.

No comments:

Post a Comment