Solar Science ||

Subscribe (?) Subscribe to RSS
A blog of solar physics

Predictions of Solar Cycle 24: Clilverd et al

Published on September 10th, 2007 in 3 Comments »

A paper published in Space Weather in 2006 used a relatively simple numerical model to add together the known solar cycles of various lengths (including the true solar cycle which is ~22 years) to produce this result:

sunspots-clilverd-etal.JPG

Now from my perspective this is ho-hum in terms of solar modelling. The underlying cycles consisted of a wave groups with constant periodicity, something that really doesn’t happen in the real solar system.

underlyingcycles-clilverd-et-al.jpg

In the real solar cycle, the cycle itself varies in length, shorter cycles being associated with climatic warming on Earth, longer cycles (>12 years) associated with cooling.

The conclusion of the authors is clear. Both solar cycle 24 and 25 are likely to be weak, Dalton-minimum style affairs. But will we get Dalton-minimum style climate cooling? Only time will tell…

Still no sign of Solar Cycle 24

Published on September 9th, 2007 in 7 Comments »

Here’s the latest trend chart from NASA. Apparently the Sun knows nothing of the predictions of NASA solar scientists regarding solar cycle 24.

Today’s pictures of the Sun show an absolutely featureless disk:

featurelesssolardisk.gif

and the magnetogram shows absolutely no sign of any magnetic activity

feratureless-magnetogram.gif

I’ve no idea what this portends for the Earth’s climate so we’ll just have to see what happens next.

NASA: Your guess is as good as ours

Published on May 20th, 2007 in 4 Comments »

Solar Cycle 24 is late. It should have arrived six months ago, but so far the sunspot cycle has failed to materialize and the Sun is extremely quiet.

So what will Solar Cycle 24 be like when it turns up?

NASA is split on the answer:

NEXT SOLAR STORM CYCLE WILL START LATE

Experts Split Over Intensity

The next 11-year cycle of solar storms will most likely start next March and peak in late 2011 or mid-2012 – up to a year later than expected – according to a forecast issued today by NOAA’s Space Environment Center in coordination with an international panel of solar experts.

Expected to start last fall, the delayed onset of Solar Cycle 24 stymied the panel and left them evenly split on whether a weak or strong period of solar storms lies ahead, but neither group predicts a record-breaker. The Space Environment Center led the prediction panel and issued the forecast at its annual Space Weather Workshop in Boulder. NASA sponsored the panel.

“The Space Environment Center’s space weather alerts, warnings, and forecasts are a critical component of NOAA’s seamless stewardship of the Earth’s total environment, from the Sun to the sea,� said retired Vice Adm. Conrad C. Lautenbacher, Ph.D., undersecretary of commerce for oceans and atmosphere and NOAA administrator.

During an active solar period, violent eruptions occur more often on the Sun. Solar flares and vast explosions, known as coronal mass ejections, shoot energetic photons and highly charged matter toward Earth, jolting the planet’s ionosphere and geomagnetic field, potentially affecting power grids, critical military and airline communications, satellites, Global Positioning System signals, and even threatening astronauts with harmful radiation. These same storms illuminate night skies with brilliant sheets of red and green known as auroras, or the northern or southern lights.

Solar cycle intensity is measured in maximum number of sunspots – dark blotches on the Sun that mark areas of heightened magnetic activity. The more sunspots there are, the more likely it is that major solar storms will occur.

In the cycle forecast issued today, half of the panel predicts a moderately strong cycle of 140 sunspots, plus or minus 20, expected to peak in October of 2011. The other half predicts a moderately weak cycle of 90 sunspots, plus or minus 10, peaking in August of 2012. An average solar cycle ranges from 75 to 155 sunspots. The late decline of Cycle 23 has helped shift the panel away from its earlier leaning toward a strong Cycle 24. Now the group is evenly split between strong and weak.

Meanwhile solar cycle 24 appears to be ever later in appearing. Here is the current situation:

This brings us to an interesting situation. After what one astrophysicist communicated to me seemed a lot like numerology in a prediction by NASA, and after statements about the strength of Solar Cycle 24 by the same group, we now have a fence-sitting position (which is always extremely uncomfortable).

The Russian Academy of Sciences annnounced a paper predicting a Dalton-minimum style cooling because of extreme weakness in the predicted strengths of Solar Cycles 24 and 25. It looks like Greenhouse Theory and the Solar Cycle Theory are about to get their sternest tests.

NASA predicts weak Solar Cycle 25

Published on March 28th, 2007 in 3 Comments »

Yes. The same organization and the same scientist that predicted a strong solar cycle 24 according to a prediction based on changes in the Earth’s magnetic field, predicts a weak solar cycle 25 based on observations of the Sun (for a change)

May 10, 2006: The Sun’s Great Conveyor Belt has slowed to a record-low crawl, according to research by NASA solar physicist David Hathaway. “It’s off the bottom of the charts,” he says. “This has important repercussions for future solar activity.”

The Great Conveyor Belt is a massive circulating current of fire (hot plasma) within the Sun. It has two branches, north and south, each taking about 40 years to perform one complete circuit. Researchers believe the turning of the belt controls the sunspot cycle, and that’s why the slowdown is important.

“Normally, the conveyor belt moves about 1 meter per second—walking pace,” says Hathaway. “That’s how it has been since the late 19th century.” In recent years, however, the belt has decelerated to 0.75 m/s in the north and 0.35 m/s in the south. “We’ve never seen speeds so low.”

According to theory and observation, the speed of the belt foretells the intensity of sunspot activity ~20 years in the future. A slow belt means lower solar activity; a fast belt means stronger activity.

So what does this mean for solar cycle 24? Nothing. The slowdown now doesn’t affect the next solar cycle (because that must follow the behavior of the Earth’s magnetic field somehow)

Here’s the prediction
predictions3_strip.jpg
What’s more disturbing to me is that NASA refuses to contemplate any changes to the Earth’s climate even though the last three times we had such a weak solar cycle, the Earth cooled (the Dalton minimum centered around 1790-1810, the Maunder Minimum from around 1645 to 1710, the Sporer Minimum centered around 1420 to 1570). Obviously these three events coinciding with global cooling are just coincidences.

But NASA does love a good catastrophic spin on its Earth science articles:

This is interesting news for astronauts. Solar Cycle 25 is when the Vision for Space Exploration should be in full flower, with men and women back on the Moon preparing to go to Mars. A weak solar cycle means they won’t have to worry so much about solar flares and radiation storms.

On the other hand, they will have to worry more about cosmic rays. Cosmic rays are high-energy particles from deep space; they penetrate metal, plastic, flesh and bone. Astronauts exposed to cosmic rays develop an increased risk of cancer, cataracts and other maladies. Ironically, solar explosions, which produce their own deadly radiation, sweep away the even deadlier cosmic rays. As flares subside, cosmic rays intensify—yin, yang.

Yin, Yang? What about the clear connection between cosmic rays and cloudiness? Nowhere to be seen.

The article does make mention of the prediction that I’ve previously cited:

Hathaway’s prediction should not be confused with another recent forecast: A team led by physicist Mausumi Dikpata of NCAR has predicted that Cycle 24, peaking in 2011 or 2012, will be intense. Hathaway agrees: “Cycle 24 will be strong. Cycle 25 will be weak. Both of these predictions are based on the observed behavior of the conveyor belt.”

Well we’ll see. There is a Russian report than claims that Solar Cycle 24 will also be weak, but I’ll have to source it.

By the way, Wikipedia’s report on the Dalton Minimum is pathetic, a clear result of the oppressive censorship of the Global Warmers on solar influence on Earth’s recent climate. The entire article reads:

The Dalton Minimum was a period of low solar activity, lasting from about 1790 to 1820. Like the Maunder Minimum and Sporer Minimum it coincided with a period of lower than average global temperatures. Low solar activity seems to be strongly correlated with global cooling, although the mechanism by which solar activity causes climate change is not well understood.

Yes. Really.

Solar Influence in the last 400 years

Published on March 22nd, 2007 in No Comments »

A paper from N. Scafetta and B. West submitted to Geophysical Research Letters:

We study the solar impact on 400 years of a global
surface temperature record since 1600. This period includes
the pre-industrial era (roughly 1600–1800 or 1600–1900),
when negligible amount of anthropogenic-added climate
forcing was present and the sun realistically was the
only climate force affecting climate on a secular scale, and
the industrial era (roughly since 1800–1900), when
anthropogenic-added climate forcing has been present
in some degree. We use a recent secular Northern
Hemisphere temperature reconstruction (Moberg et al.,
2005), three alternative total solar irradiance (TSI) proxy
reconstructions (Lean et al., 1995; Lean, 2000; Wang et al.,
2005) and a scale-by-scale transfer climate sensitivity model
to solar changes (Scafetta and West, 2005, 2006). The
phenomenological approach we propose is an alternative to
the more traditional computer-based climate model approach,
and yields results proven to be almost independent on the
secular TSI proxy reconstruction used. We find good
correspondence between global temperature and solar
induced temperature curves during the pre-industrial period
such as the cooling periods occurring during the Maunder
Minimum (1645–1715) and the Dalton Minimum (1795–
1825). The sun might have contributed approximately 50%
of the observed global warming since 1900 (Scafetta and
West, 2006). We briefly discuss the global cooling that
occurred from the medieval maximum (1000–1100 AD)
to the 17th century minimum.

So they used the Moberg reconstruction. At least it wasn’t the Hockey Stick.

Previous predictions of solar cycle 24

Published on March 21st, 2007 in 6 Comments »

From NASA website:

Solar cycle 24, due to peak in 2010 or 2011 “looks like its going to be one of the most intense cycles since record-keeping began almost 400 years ago,” says solar physicist David Hathaway of the Marshall Space Flight Center. He and colleague Robert Wilson presented this conclusion last week at the American Geophysical Union meeting in San Francisco.

Their forecast is based on historical records of geomagnetic storms.

Hathaway explains: “When a gust of solar wind hits Earth’s magnetic field, the impact causes the magnetic field to shake. If it shakes hard enough, we call it a geomagnetic storm.” In the extreme, these storms cause power outages and make compass needles swing in the wrong direction. Auroras are a beautiful side-effect.

Hathaway and Wilson looked at records of geomagnetic activity stretching back almost 150 years and noticed something useful:. “The amount of geomagnetic activity now tells us what the solar cycle is going to be like 6 to 8 years in the future,” says Hathaway. A picture is worth a thousand words:

hathaway1_strip2.jpg

Above: Peaks in geomagnetic activity (red) foretell solar maxima (black) more than six years in advance. [More]

In the plot, above, black curves are solar cycles; the amplitude is the sunspot number. Red curves are geomagnetic indices, specifically the Inter-hour Variability Index or IHV. “These indices are derived from magnetometer data recorded at two points on opposite sides of Earth: one in England and another in Australia. IHV data have been taken every day since 1868,” says Hathaway.

Cross correlating sunspot number vs. IHV, they found that the IHV predicts the amplitude of the solar cycle 6-plus years in advance with a 94% correlation coefficient.

“We don’t know why this works,” says Hathaway. The underlying physics is a mystery. “But it does work.”

And here’s the prediction for Solar Cycle 24 based on this “mystery”:
hathaway2_med.gif
Never mind that this thing looks a lot like numerology - if its from NASA and has a nice graph it must be worth something

NASA warns of coming solar storm

Published on March 21st, 2007 in No Comments »

From the NASA website:

This week researchers announced that a storm is coming–the most intense solar maximum in fifty years. The prediction comes from a team led by Mausumi Dikpati of the National Center for Atmospheric Research (NCAR). “The next sunspot cycle will be 30% to 50% stronger than the previous one,” she says. If correct, the years ahead could produce a burst of solar activity second only to the historic Solar Max of 1958.

That was a solar maximum. The Space Age was just beginning: Sputnik was launched in Oct. 1957 and Explorer 1 (the first US satellite) in Jan. 1958. In 1958 you couldn’t tell that a solar storm was underway by looking at the bars on your cell phone; cell phones didn’t exist. Even so, people knew something big was happening when Northern Lights were sighted three times in Mexico. A similar maximum now would be noticed by its effect on cell phones, GPS, weather satellites and many other modern technologies.

Now that isn’t the only prediction for Solar Cycle 24. I’ll look up the references to other predictions and post them.

Welcome to Solar Science

Published on March 21st, 2007 in 1 Comment »

This blog was setup by me to collate news on solar physics, predictions of future solar activity and possible correlations between solar activity and the Earth’s climate of the past.

I don’t come to any firm conclusions about the effect of solar variation on the climate of the Earth. I am merely reporting what I see.


The Sun

Firefox 3

Firefox 3