Thanks Malcolm. Sorry, but it doesn't seem to have much credibility.
From cursory reading of the main article and linked source, one might conclude that the sun will dim by a huge amount. It won't. Magnetic activity and sunspot numbers will probably drop over the next few cycles, but the thermal output of the sun is only very slightly influenced by magnetic activity and will vary by maybe 0.1-0.2%, certainly nothing like the 60% that might be concluded from reading the articles.
It seems to me to be terribly poor reporting to make the leap from a fairly arcane maths paper to an assertion that a new iceage is coming....
No one is more surprised than Valentina Zharkova that her research prompted a worldwide media storm over the next ice age.
That's because her research never even mentioned an ice age.
...
“In the press release, we didn’t say anything about climate change,” she told USA TODAY. “My guess is when they heard about Maunder minimum, they used Wikipedia or something to find out more about it.”
Another blatant distortion by the media spin machine. Every blogger and his dog is an armchair expert these days and free to put their twist and take even on actual facts. It's come to a point that almost everything you read online is rubbish. Have you seen all those "science" pages on FB? They're more interested in jacking traffic with their side ads than anything else. The whole point is spamming the internet to generate some revenue.
The radiative forcing from a Grand Solar Minimum works out at about -0.2-0.5W/sq m, compared to over +1.7W/sq m (and increasing) for the net forcing imbalance caused by our greenhouse gas emissions. Or put another way, a Grand Minimum would buy us less than 10 (probably less than 5) years worth of extra CO2 emissions in terms of radiative forcing. Note that the forcing difference is not the same as the level of lowered solar output, partly because the Earth is spherical, and partly because some shortwave energy is reflected to space.
As a picture is worth a thousand words, here's Figure 2 from Feulner and Rahmstorf (2010), which encapsulates the issue neatly - see if you can spot the difference in warming trend between a Grand Minimum and no solar activity reduction, even better - look for the "Ice Age"...
I had my suspicion but needed more input, I have been concentrating more of my time in the electronics industry than Physics so it nice to know that it could be a beat up.
I remember a fairly hefty discussion sometime ago on the forum.
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Much of this is nothing new. It sounds as though the paper announced a more accurate model to predict the solar cycle and said nothing about a mini ice age.
The low sunspot / magnetic activity in solar cycle 25 has been predicted by other authors for at least 10 years. Solar Physicist David Hathaway predicted this back in 2006. See -
The predicted 60% reduction, is a reduction in things like magnetic activity sunspot numbers and results in reductions of related phenomena like prominences and coronal mass ejections. It may also result in a small reduction in solar energy output but nothing like 60%. A 60% reduction in solar output would not cause a mini ice age but would cause an apocalyptic change to the the Earth's temperature. Mars gets about 40% of the insolation the Earth receives due to its greater distance from the Sun.
....this article made no claims or predictions in terms of any ecological systems on the earth (such as climate and global temperatures). it was purely an article on an astrophysical phenomenon. Also the conclusion that the sun's activity will be reduced by about 60% relates to sun spots, solar flares and coronal discharges etc. It is NOT a reduction in solar output by 60%. In fact the suns energy output changes over very long time periods, even with these dynamic one off solar effects or bursts of energy.
A follow up media story on the prediction of a mini ice age based on this article has also been published which back tracks
Cheer up, we’re not heading into 'mini ice age' just yet
Scientists created a buzz last week saying our planet is just 15 years from a new ‘mini ice age’ that could cause awfully cold winters with rivers like Thames freezing over.
The trouble is - it wasn't scientists who made these claims, it was all started by ignorant, ill-informed journalists,
They didn't know how to read a scientific paper, and they didn't bother to get it fact-checked (e.g. by asking the authors, or an experienced Science Journalist, to confirm the accuracy of their version). Once the first scare-piece was published, it was then picked up and re-published numerous times by lazy so-called "journalists" who just scour the web for "stuff", and re-badge it as their own work.
And once the story gets picked up by the electronic media, there is no chance of objectivity returning to the coverage - any talking head (preferably, a photogenic one!) can be presented as an "expert".
Joel Hurrey is an actor, model and "experienced TV presenter". His CV includes appearing on Domestic Blitz, co-hosting Entertainment, Travel and Morning shows on GO! and Seven, and a Surfing show on FOX sport. Strangely, he seems to have forgotten to list his environmental science and astrophysics credentials in his publicity material: http://www.starnow.com.au/joelhurrey/
(I guess as a bona fide "surfing expert", he does at least have some interest in the weather.)
I wonder does our galactic position have any bearing on weather.
Could there be a mechanism, via gravity for example but not exclusively.
weather or climate?
The main Cycles for climate are described by the Milankovitch cycles, but they occur over very long periods - thousands of years. There are 3 or 4 from memory and relate to the earths orbit around the sun, axial tilt (?) etc
As far as galactic position is concerned, I dont know of any direct effects on the Earth's climate.
Although one could argue that the earth bobbing up and down every 30 million years as it orbits the center of our galaxy, perturbing objects in the Oort Cloud which then plunge inwards towards the sun is a source of climate disruption should that object collide with the Earth (more of a catastrophe on the Earth than a disruption in climatic conditions)
The force of Gravity is actually a very weak fundamental force (the weakest to be precise) - but who knows what direct or indirect role it could play
Although I said weather I was thinking climate.
Today I am not curious it is too cold and my interest is only in gathering fire wood.
As to journalism I learnt long ago to be careful in forming views without additional research.
Remember Steven Hawking and no black holes news.
I could make a list but I need not as I think few are really fooled long term.
The radiative forcing from a Grand Solar Minimum works out at about -0.2-0.5W/sq m, compared to over +1.7W/sq m (and increasing) for the net forcing imbalance caused by our greenhouse gas emissions. Or put another way, a Grand Minimum would buy us less than 10 (probably less than 5) years worth of extra CO2 emissions in terms of radiative forcing. Note that the forcing difference is not the same as the level of lowered solar output, partly because the Earth is spherical, and partly because some shortwave energy is reflected to space.
As a picture is worth a thousand words, here's Figure 2 from Feulner and Rahmstorf (2010), which encapsulates the issue neatly - see if you can spot the difference in warming trend between a Grand Minimum and no solar activity reduction, even better - look for the "Ice Age"...
All very nice, except that your graph doesn't go back hundreds of years - to when there was a mini-ice age - as for example do the reconstruction graphs you previously linked me to last year.
The claims in relation to low sunspot activity causing mini-ice ages doesn't relate to the heat out-put by the sun, rather to the respective effects of solar wind and cosmic rays on cloud formation.
