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Archive for the ‘News and Views’ Category

Solar Climate Linkages

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Just a couple of interesting articles that I think deserve wider readership.

Henrik Svensmark on the coming global cooling: “enjoy global warming while it lasts” (this is a Google translation from Danish, so the English is a little crazy)

While the sun sleeps

HENRIK SVENSMARK, Professor, DTU, Copenhagen

Indeed, global warming stopped and a cooling is beginning. No climate model has predicted a cooling of the Earth, on the contrary. This means that projections of future climate is unpredictable, writes Henrik Svensmark.

The star which keeps us alive, has over the last few years almost no sunspots, which are the usual signs of the sun’s magnetic activity.

Last week, reported the scientific team behind Sohosatellitten (Solar and Heliospheric Observatory) that the number of sunspot-free days suggest that solar activity is heading towards its lowest level in about 100 years’. Everything indicates that the Sun is moving into a hibernation-like state, and the obvious question is whether it has any significance for us on Earth.

If you ask the International Panel on Climate Change IPCC, representing the current consensus on climate change, so the answer is a reassuring ‘nothing’. But history and recent research suggests that it is probably completely wrong. Let us take a closer look at why.

Solar activity has always varied. Around the year 1000, we had a period of very high solar activity, which coincided with the medieval warmth. It was a period when frosts in May was an almost unknown phenomenon and of great importance for a good harvest. Vikings settled in Greenland and explored the coast of North America. For example, China’s population doubled over this period. But after about 1300, the earth began to get colder and it was the beginning of the period we now call the Little Ice Age. In this cold period all the Viking settlements in Greenland disappeared. Swedes [were surprised to see Denmark to freeze over in ice], and the Thames in London froze repeatedly. But more serious was the long periods of crop failure, which resulted in a poorly nourished population, because of disease and hunger [population was reduced] by about 30 per cent in Europe.

Read on here

New linkage between solar cycle and Earth’s atmosphere discovered

Scientists discover surprise in Earth’s upper atmosphere

By Stuart Wolpert

Heejeong Kim and Larry Lyons

Heejeong Kim and Larry Lyons

UCLA atmospheric scientists have discovered a previously unknown basic mode of energy transfer from the solar wind to the Earth’s magnetosphere. The research, federally funded by the National Science Foundation, could improve the safety and reliability of spacecraft that operate in the upper atmosphere.

“It’s like something else is heating the atmosphere besides the sun. This discovery is like finding it got hotter when the sun went down,” said Larry Lyons, UCLA professor of atmospheric and oceanic sciences and a co-author of the research, which is in press in two companion papers in the Journal of Geophysical Research.

The sun, in addition to emitting radiation, emits a stream of ionized particles called the solar wind that affects the Earth and other planets in the solar system. The solar wind, which carries the particles from the sun’s magnetic field, known as the interplanetary magnetic field, takes about three or four days to reach the Earth. When the charged electrical particles approach the Earth, they carve out a highly magnetized region — the magnetosphere — which surrounds and protects the Earth.

Charged particles carry currents, which cause significant modifications in the Earth’s magnetosphere. This region is where communications spacecraft operate and where the energy releases in space known as substorms wreak havoc on satellites, power grids and communications systems.

The rate at which the solar wind transfers energy to the magnetosphere can vary widely, but what determines the rate of energy transfer is unclear.

“We thought it was known, but we came up with a major surprise,” said Lyons, who conducted the research with Heejeong Kim, an assistant researcher in the UCLA Department of Atmospheric and Oceanic Sciences, and other colleagues.

Read on here

Written by John A

September 11, 2009 at 12:13 pm

Offline: We've gone temporarily blind

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The SOHO instruments are offline while new software commands are uploaded. As the main instruments are offline, the other CCD systems are being baked out (heated up to clear dead pixels)

From Spaceweather.com

Solar and Heliospheric Observatory (SOHO) is having a minor problem. SOHO’s white light solar telescope is temporarily offline while new commands and data tables are uploaded to the spacecraft. Normal operations are expected to resume in a few days.

Hence no updates on the state of the Sun.

The Sun could have a sudden burst of activity and we’d never know.

Written by John A

August 7, 2009 at 11:02 am

Posted in News and Views

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This Quiet Sun

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The Sun has gone back to blank after having had just one sunspot group that caused otherwise rational people to go off their heads…

Here’s the magnetogram of the Sun showing precisely nothing that presages any sunspot formation:

Magnetogram of the Sun 16/07/2009

Magnetogram of the Sun 16/07/2009

As a comparison, here is the sun image from the Extreme ultraviolet Imaging Telescope at 304 ångstroms for today and near solar maximum in 2000 by way of comparison

Sun at 17/07/2009 (left) and near solar maximum 31/05/2000

Sun at 17/07/2009 (left) and near solar maximum 31/05/2000 (right)

Now its easy to see how quiet the Sun really is at the moment. The prominences are weak, the coronal holes are very small, the corona (the solar atmosphere) shrunken.

All of this can be seen to be normal behaviour for the Sun, except that this hiatus between Solar Cycle 23 finally winding down and the next cycle is unprecedented in nearly a hundred years. (By the way, the overuse of “unprecedented” by climate alarmists has me wincing at using it as a cliché)

Eventually the solar cycle must return. The question is whether solar scientists gain insight into the behaviour of the Sun by understanding why their models failed (see below). The result can only be better science.

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Written by John A

July 17, 2009 at 5:21 pm

NASA: The mystery of the missing sunspots solved?

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Hot off the press.

NASA announces yet another explanation for the late arrival of Solar Cycle 24 (nearly two years after it was supposed to have started).

June 17, 2009: The sun is in the pits of a century-class solar minimum, and sunspots have been puzzlingly scarce for more than two years. Now, for the first time, solar physicists might understand why.

At an American Astronomical Society press conference today in Boulder, Colorado, researchers announced that a jet stream deep inside the sun is migrating slower than usual through the star’s interior, giving rise to the current lack of sunspots.

Rachel Howe and Frank Hill of the National Solar Observatory (NSO) in Tucson, Arizona, used a technique called helioseismology to detect and track the jet stream down to depths of 7,000 km below the surface of the sun. The sun generates new jet streams near its poles every 11 years, they explained to a room full of reporters and fellow scientists. The streams migrate slowly from the poles to the equator and when a jet stream reaches the critical latitude of 22 degrees, new-cycle sunspots begin to appear.


Original Caption:
Above: A helioseismic map of the solar interior. Tilted red-yellow bands trace solar jet streams. Black contours denote sunspot activity. When the jet streams reach a critical latitude around 22 degrees, sunspot activity intensifies.

Howe and Hill found that the stream associated with the next solar cycle has moved sluggishly, taking three years to cover a 10 degree range in latitude compared to only two years for the previous solar cycle.

The jet stream is now, finally, reaching the critical latitude, heralding a return of solar activity in the months and years ahead.

“It is exciting to see”, says Hill, “that just as this sluggish stream reaches the usual active latitude of 22 degrees, a year late, we finally begin to see new groups of sunspots emerging.”

The current solar minimum has been so long and deep, it prompted some scientists to speculate that the sun might enter a long period with no sunspot activity at all, akin to the Maunder Minimum of the 17th century. This new result dispells those concerns. The sun’s internal magnetic dynamo is still operating, and the sunspot cycle is not “broken.”

So we should be seeing SC24 sunspots appearing now that the jet stream has reached the critical latitude of 22° ?

Let’s check out of the window:

The spotless disk of the Sun

The spotless disk of the Sun

Magnetogram shows little magnetic behaviour

Magnetogram shows little magnetic behaviour

OK, maybe it was just an off day on the Sun. What about the trend?

Sunspot trends to May 2009

So far, indistinguishable from zero.

Here’s the 3D view of what the solar scientists are tracking/modelling (click to see the movie):

This movie reveals motions of the Sun’s interior as measured with helioseismology on data from GONG and SOHO/MDI. East to west motion is color coded: blue is slow, red is fast. A red band in the outer third of the Sun moves slowly down from near each pole toward the equator; that band is the jet stream that is associated with sunpot emergence and the solar cycle. As of early 2009 the Cycle 24 jet streams have just reached N/S 22 degrees latitude, and new sunspots are beginning to emerge.

Now I hate to be a killjoy, but all of this effort has failed to convince me that a deep down “jetstream” of charged plasma reaching a “critical” latitude can explain why the Sun remains so very quiet.

On SolarCycle24.com, they’ve got yet another sun speck recorded yesterday, that by today had disappeared. Exactly the same behaviour we’ve been having for 12 months with no end in sight.

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Written by John A

June 17, 2009 at 11:36 am

Ken Tapping: One year on into the minimum

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This blog has quiet periods just like the Sun 😉

I’ve just been in e-mail correspondance with Dr Kenneth Tapping, asking him to comment on the progress of the solar minimum and his opinion on the likely size of SC24 when it does deign to appear.

Dear Dr Tapping

After you published your rebuke to Investor’s Business Daily, I put your entire reply onto my blog (see http://solarscience.auditblogs.com/2008/04/22/ken-tapping-the-current-solar-minimum/ ) which I notice is the second listing when anyone googles your name. I hope you didn’t mind.

Since that reply the Sun has appeared to have gone into an even deeper slumber than it was when you wrote your article, more than a year ago. You ended that article with a statement

AT THE MOMENT IT IS UNJUSTIFIED TO ASSUME THE SUN IS UNDERGOING A SIGNIFICANT CHANGE IN BEHAVIOUR. ON THE BASIS OF SUNSPOT NUMBER DATA, WE CANNOT ASSUME ANYTHING ODD IS HAPPENING UNLESS THE NEXT CYCLE DELAYS ITS START INTO 2009 OR 2010

Well it’s now nearly mid-2009 and the only spots to be seen very very occasionally are SC23 polarity.

Do you have any further comment on the Sun’s (lack of) activity? Are we close to unusual times in solar activity? Is the sun undergoing a significant change in behaviour?

Best regards

John

He replied [with my emphasis]

Hi John,

I’ve just got back here from the Space Weather Workshop, which was held in Boulder, Colorado. The opinion there is that the next cycle is coming, although forecasts are for a low cycle with a late start.

Our radio telescopes have detected no sign of the new cycle yet. However a statistical study of indices that I have been doing suggests the Sun did show a significant change in behaviour over the last few years, but that things are starting to slip back towards the normal situation, which could suggest the Sun is at least showing signs of waking up again. It’s deciding to take an additional lie-in cannot be ruled out.

Activity is certainly very low
.

Regards,

Ken

When I asked for that “statistical study of indices”, Dr Tapping replied that it was being submitted to a journal and he’d let me know when its in pre-print – which is fine by me.

I think it’s fair to say that all solar scientists have been caught out by the length of the solar minimum and the delay to SC24. In subsequent posts I’ll be reviewing the prognostications of solar models, in an effort to understand what exactly goes into predictions of solar cycles.

In other news, as reported on Watts Up With That:

NOAA/SWPC will be releasing an update to the Solar Cycle 24 Prediction on Friday, May 8, 2009 at noon Eastern Daylight Time (1600 UT) at a joint ESA/NASA/NOAA press conference

I can hardly wait.

Written by John A

May 7, 2009 at 12:55 pm

Solar Cycle 24 finally arrives

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Not a speck. Not a low latitude could-be-a-SC23 spot.

The real deal.

Sun on 13-10-2008 showing SC24 spot

Sun on 13-10-2008 showing SC24 spot

The polarity is definitely reversed from the previous cycle. Its a high latitude spot. The companion spot is reverse polarity to the main spot.

Looks good to me.

The STEREO image (allows us to look around the limb of the Sun and see what’s coming) suggest an even larger area of activity at about the same latitude.

Stereo Image 12-10-2008

Stereo Image 12-10-2008

Now we wait to see if the SC24 persists.

The magnetogram shows the SC24 polarity:

Magnetogram from 13-10-2008 showing SC24 polarity

Magnetogram from 13-10-2008 showing SC24 polarity

The solar magnetic field for September has just been published (as graphed by Anthony Watts) and shows the magnetic field to be at a historically low level, as NASA had already noted.

solar_ap_index_10062008.png

This may just prove to be the bottom of the Solar Cycle (yes, I’m sticking my neck out). Now we wait to see what happens next, because I’m not convinced that anyone really has a clue.

Written by John A

October 11, 2008 at 11:16 pm

The Sun is in a deep minimum

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Yesterday I pulled this magnetogram picture from the SOHO website

20081006_0141_mdimag_512.jpg

Ignoring the phage in the Southern Hemisphere (which is SC23 polarized, natch) there is no magnetic activity at all to speak of.

Throw in the result announced by NASA in the last few days:

“The sun’s million mile-per-hour solar wind inflates a protective bubble, or heliosphere, around the solar system. It influences how things work here on Earth and even out at the boundary of our solar system where it meets the galaxy,” said Dave McComas, Ulysses’ solar wind instrument principal investigator and senior executive director at the Southwest Research Institute in San Antonio, Texas. “Ulysses data indicate the solar wind’s global pressure is the lowest we have seen since the beginning of the space age.”

and

In 2007, Ulysses made its third rapid scan of the solar wind and magnetic field from the sun’s south to north pole. When the results were compared with observations from the previous solar cycle, the strength of the solar wind pressure and the magnetic field embedded in the solar wind were found to have decreased by 20 percent. The field strength near the spacecraft has decreased by 36 percent.

“The sun cycles between periods of great activity and lesser activity,” Smith said. “Right now, we are in a period of minimal activity that has stretched on longer than anyone anticipated.”

Its clear that the Sun has entered a phase that we might never have seen before with anything like modern instrumentation.

The spots on the Sun have become so evanescent and small that we now have the ludicrous arguments over whether a darkened spot that lasts a few hours is counted as a spot or a speck. Anthony Watts refers to this as “Speckwatch” and furthermore even these specks have been SC23 not SC24 polarized.

What is clear is that these spots or specks are way below the range at which our scientific ancestors from the 18th and 19th Centuries could ever have detected.

Written by John A

October 6, 2008 at 1:54 pm

Posted in News and Views

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