Posts Tagged ‘sunspots’

Solar flare erupting from a sunspot [image credit:]

Who knew!? – asks ScienceAlert. The article links to an interesting new paper on solar cycles, which makes some predictions for the current SC 25 (see section 3.2: Forecasting Using the Solar Unit Cycle). One of those is that it should end in October 2031 ± 9 months, and the authors go on to suggest forthcoming NASA and ESA missions make it probable that ‘Cycle 25 will be the last solar activity cycle that is not fully understood.’
– – –
Something weird is going on with the Sun.

So far, almost every day in 2022 it has erupted in flares and coronal mass ejections, some of which were the most powerful eruptions our star is capable of.

By itself, an erupting Sun is not weird. It erupts regularly as it goes through periods of high and low activity, in cycles that last roughly 11 years.

The current activity is significantly higher than the official NASA and NOAA predictions for the current solar cycle, and solar activity has consistently exceeded predictions as far back as September 2020.

But a solar scientist will tell you that even this isn’t all that weird.


Sunspots [image credit: NASA]

The Sun may still have a surprise or two for solar cycle 25 theorists, but what we hear is: “I believe this will likely be the best forecast to come out of one of the NOAA/NASA Cycle prediction panels.” The article below doesn’t include the question mark in its headline.
– – –
The Sun is waking up, says Sky and Telescope.

In recent weeks, NASA has announced X-class solar flares, observers have seen large sunspot groups with the unaided eye, and online services have issued multiple aurora alerts even for mid-latitudes.

After years of quiescence — the Sun was more often spotless than not in 2018, 2019, and 2020 — the change of pace is exciting solar observers.


Trend or blip? The former looks more likely at the moment, but the sun can cause surprises.

April 5, 2022: New sunspot counts from NOAA confirm that Solar Cycle 25 is racing ahead of the official forecast–and the gap is growing:

See the complete labeled plot or play with an interactive version from NOAA

Sunspot counts have now exceeded predictions for 18 straight months. The monthly value at the end of March was more than twice the forecast, and the highest in nearly 7 years.

The “official forecast” comes from the Solar Cycle Prediction Panel, a group of scientists representing NOAA, NASA and International Space Environmental Services (ISES). The Panel predicted that Solar Cycle 25 would peak in July 2025 as a relatively weak cycle, similar in magnitude to its predecessor Solar Cycle 24. Instead, Solar Cycle 25 is shaping up to be stronger.

In March 2022, the sun produced 146 solar flares, including one X-flare and 13 M-flares. Auroras were sighted as far south…

View original post 38 more words

Solar cycle 25 is about to reach the interesting stage, when we find out what it’s really made of.

March 23, 2022: Solar Cycle 25 is intensifying–and Earth’s upper atmosphere is responding.

“The Thermosphere Climate Index (TCI) is going up rapidly right now,” reports Linda Hunt of Science Systems and Applications, Inc. “It has nearly tripled in the past year.”

TCI is a number published daily by NASA, which tells us how hot Earth’s upper atmosphere is. The thermosphere, the very highest layer of gas, literally touches space and is a sort of “first responder” to solar activity. Hunt created this plot showing how TCI has unfolded during the last 7 solar cycles.  Solar Cycle 25 (shown in blue) is just getting started:

“So far Solar Cycle 25 is well ahead of the pace of Solar Cycle 24,” notes Hunt. If this trend continues, the thermosphere could soon hit a 20-year high in temperature.

Before we go any farther, a word of caution: This does not mean Earth is…

View original post 198 more words

Huge Explosion on the Farside of the Sun

Posted: February 20, 2022 by oldbrew in Solar physics

The culprit could be coming into view in the next day or so.

Feb. 17, 2022: New images from the Solar and Heliospheric Observatory (SOHO) are giving us a better look at yesterday’s farside explosion. SOHO coronagraphs recorded the most dramatic CME in years:

No, there won’t be a geomagnetic storm. The explosion happened on the farside of the sun, so the CME is heading away from Earth. We dodged a bullet.

Some readers have asked “How strong was the underlying solar flare?” We don’t know. Solar flares are classified by their X-ray output, but there are no spacecraft on the farside of the sun with X-ray sensors. Best guess: It was an X-flare.

You might suppose that the farside of the sun is hidden from view. However, researchers using a technique called “helioseismology” can make crude maps of the sun’s hidden hemisphere. Their latest map reveals a huge farside active region:

The black blob is a sunspot group–a big one–and…

View original post 138 more words

Solar Cycle 25 Update

Posted: January 12, 2022 by oldbrew in Cycles, data, solar system dynamics
Tags: ,

It’s still early in the cycle so let’s see what the next 1-2 years bring.

Jan. 10, 2022: Solar Cycle 25 is heating up. New sunspot counts from NOAA confirm that the young solar cycle is outrunning the official forecast. You are here:

Actual sunspot counts have now exceeded predictions for 15 straight months. The monthly value at the end of December 2021 was more than twice the forecast, and the highest in more than 5 years.

The “official forecast” comes from the Solar Cycle Prediction Panel representing NOAA, NASA and International Space Environmental Services (ISES). Using a variety of leading indicators, the Panel predicted that Solar Cycle 25 would peak in July 2025 as a relatively weak cycle, similar in magnitude to its predecessor Solar Cycle 24. Instead, Solar Cycle 25 is shaping up to be stronger.

Sky watchers have already noticed the change. “We are definitely seeing the effects on the ground in the Arctic!” reports Chad Blakley of the Swedish tour guide…

View original post 197 more words

Solar Tsunami and CME

Posted: August 30, 2021 by oldbrew in Solar physics


Sunspot AR 2860 is a ‘monster’.

Aug. 27, 2021: Sunspot AR2859 erupted on Aug. 26th, producing a C3-class solar flare: movie. The flare, however, was not the main attraction. The eruption also caused a massive “solar tsunami.” Watch the shadowy wave ripple across the sun in this false-color ultraviolet movie from NASA’s Solar Dynamics Observatory:

The expanding circular shadow is a wave of hot plasma and magnetism. Based on the time it took to reach the next sunspot, halfway around the sun, the tsunami was traveling faster than 110,000 mph.

Solar tsumanis always herald a CME, and this one was no exception. Soon after the tsunami broke, SOHO coronagraphs detected a plasma cloud leaving the sun: movie.

Update: NOAA analysts have modeled the CME’s trajectory. They predict an Earth impact during the late hours of Aug. 29th, possibly sparking G1-class geomagnetic storms through midday on Aug. 30th.   Aurora alerts:SMS Text.


View original post 134 more words


Our magnetic Sun [image credit:]

The declining phase of the current solar cycle 25 is predicted to be short. Whether that would follow a low peak remains to be seen, but not much has happened so far in the cycle.
– – –
Violent activity on our Sun leads to some of the most extreme space weather events on Earth, impacting systems such as satellites, communications systems, power distribution and aviation, says

The roughly 11-year cycle of solar activity has three ‘seasons’, each of which affects the space weather felt at Earth differently: (i) solar maximum, the sun is active and disordered, when space weather is stormy and events are irregular (ii) the declining phase, when the sun and solar wind becomes ordered, and space weather is more moderate and (iii) solar minimum, when activity is quiet.

In a new study led by the University of Warwick and published in The Astrophysical Journal, scientists found that the change from solar maximum to the declining phase is fast, happening within a few (27 day) solar rotations.



Credit: The Weather Network

Of course they could have been. The question is, were they? Assigning weather events to ‘global warming’ is ambiguous without a full definition of what the assigner means by that term. Jet stream blocking events discussed below are well-known to meteorologists, and constantly claiming them as evidence of a new human-caused problem with the climate is a stretch, to say the least.
– – –
The recent record-shattering heat wave in the Pacific northwest and devastating floods in western Europe have both been ascribed to global warming by many climate scientists, says Science Under Attack.

But an alternative explanation, voiced by some climatologists yet ignored by the mainstream media, is that the disasters were caused by the phenomenon of jet-stream blocking – which may or may not be a result of global warming, and could instead arise from a weakening of the sun’s output.

Blocking refers to the locking in place for several days or weeks of the jet stream, a narrow, high-altitude air current that flows rapidly from west to east in each hemisphere and governs much of our weather.

One of the more common blocking patterns is known as an “omega block,” a buckling of the jet stream named for its resemblance to the upper-case Greek letter omega, that produces alternating, stationary highs and lows in pressure as shown in the figure below. Under normal weather conditions, highs and lows move on quickly.

According to the blocking explanation, the torrential rains that hovered over parts of western Germany, Belgium and the Netherlands came from a low-pressure system trapped between two blocking highs to the west and east – the opposite situation to that shown in the figure.

Precipitation tends to increase in a warmer world because of enhanced evap­oration from tropical oceans, resulting in more water vapor in the atmosphere. So with a blocking low stuck over the Rhine valley and the ground already saturated from previous rainfall, it’s not surprising that swollen rivers overflowed and engulfed whole villages.

A similar argument can be invoked to explain the intense “heat dome” that parked itself over British Columbia, Washington and Oregon for five blisteringly hot days last month. In this case, it was a region of high pressure that was pinned in place by lows on either side, with the sweltering heat intensified by the effects of La Niña on North America.

Several Pacific northwest cities experienced temperatures a full 5 degrees Celsius (9 degrees Fahrenheit) above previous records.

There’s little doubt that both of these calamitous events resulted from jet-stream omega blocks. Blocking can also induce cold extremes, such as the deep freeze endured by Texas earlier this year. But how can blocking be caused by the sun?

Over the 11-year solar cycle, the sun’s heat and visible light fluctuate, as does its production of invisible UV, which varies much more than the tenth of a percent change in total solar output. It’s thought that changes in solar UV irradiance cause wind shifts in the stratosphere (the layer of the atmosphere above the troposphere), which in turn induce blocking in the tropospheric jet stream via a feedback effect.

Blocking can also stem from other mechanisms. In the North Atlantic at least, a 2008 research paper found that during periods of low solar activity, blocking events in more eastward locations are longer and more intense than during higher solar activity.

Right now we’re entering a stretch of diminished solar output, signified by a falloff in the average monthly number of sunspots as depicted in the next figure.

The decline in the maximum number of sunspots over the last few cycles likely heralds the onset of a grand solar minimum, which could usher in a period of global cooling.

Full article here.


In a recent post we looked at the average daily sunspot numbers, finding that far from the claimed decades-long decline of solar strength, averages were high from 1933-2008 followed by a sharp decline in the recently-ended solar cycle 24.

This time the focus moves to another metric from the same source, Wikipedia’s List of solar cycles.

After the main table of data they introduce another one, stating:
The following table is instead divided into (unofficial) cycles starting and ending with a maximum, to give a better feel for the number of spotless days associated with each minimum.

For this short exercise the ‘Spotless days’ column of data will be split into two groups of six, comparing the overall average of each from the list.


This quote from the report stood out: ‘there are long-lasting periods of strong and weak solar activity, which is also reflected in the climate on Earth.’ Worth noting as we proceed through a period of weak activity right now.
– – –
An international team of researchers led by ETH Zurich has reconstructed solar activity back to the year 969 using measurements of radioactive carbon in tree rings, reports

Those results help scientists to better understand the dynamics of the sun and allow more precise dating of organic materials using the C14 method.

What goes on in the sun can only be observed indirectly. Sunspots, for instance, reveal the degree of solar activity—the more sunspots are visible on the surface of the sun, the more active is our central star deep inside.


Is it a coincidence that we’re just past the end of the lowest sunspot cycle for over a century?

Dec. 28, 2020: Something strange is happening 50 miles above Antarctica. Or rather, not happening. Noctilucent clouds (NLCs), which normally blanket the frozen continent in December, are almost completely missing. These images from NASA’s AIM spacecraft compare Christmas Eve 2019 with Christmas Eve 2020:

“The comparison really is astounding,” says Cora Randall of the University of Colorado’s Laboratory for Atmospheric and Space Physics. “Noctilucent cloud frequencies are close to zero this year.”

NLCs are Earth’s highest clouds. They form when summertime wisps of water vapor rise up from the poles to the edge of space. Water crystallizing around specks of meteor dust 83 km (~50 miles) above Earth’s surface creates beautiful electric-blue structures, typically visible from November to February in the south, and May to August in the north.

A crucial point: Noctilucent clouds form during summer. And that’s the problem. Although summer officially started in Antarctica one week…

View original post 237 more words


‘Scientists use an extended, 22-year solar cycle to make the forecast’ is the sub-heading to the article. In other words the Hale cycle. At the end of last year The Talkshop detailed Plenty of predictions from a wide range of research groups, including our own, made in 2013. A possible (?) early indicator is that the ‘smoothed minimum’ of sunspots at the start of solar cycle 25 is given by Wikipedia as 1.8, the lowest recorded since cycle 7 (0.2) in 1823.
– – –
In direct contradiction to the official forecast, a team of scientists led by the National Center for Atmospheric Research (NCAR) is predicting that the Sunspot Cycle that started this fall could be one of the strongest since record-keeping began, says NCAR News.

In a new article published in Solar Physics, the research team predicts that Sunspot Cycle 25 will peak with a maximum sunspot number somewhere between approximately 210 and 260, which would put the new cycle in the company of the top few ever observed.


Sunspots [image credit: NASA]

Wikipedia’s Solar activity and climate web page says:
Solar activity has been on a declining trend since the 1960s, as indicated by solar cycles 19-24, in which the maximum number of sunspots were 201, 111, 165, 159, 121 and 82, respectively.

We’re probably not surprised that they prefer a metric which appears to support their often-expressed view in various climate-related pages that modern global warming can’t be natural.

But is the sunspot maximum the most relevant metric to judge the level of solar activity by? Another Wikipedia page is its List of Solar Cycles.


Quiet sun [image credit: NASA]

They picked an interesting time to study the Sun, as it starts to emerge from an unusually deep and long-lasting solar minimum. What effect this might have on Earth’s weather systems of course remains to be seen, but could be hard to quantify. The researchers have a lot of data to work through, and are hoping for ‘unprecedented insights into the sun’.
– – –
Three of the Solar Orbiter spacecraft’s instruments, including Imperial’s magnetometer, have released their first data, reports

The European Space Agency’s Solar Orbiter spacecraft launched in February 2020 on its mission to study the sun and it began collecting science data in June.

Now, three of its ten instruments have released their first tranche of data, revealing the state of the sun in a ‘quiet’ phase.

The sun is known to follow an 11-year cycle of sunspot activity and is currently almost completely free of sunspots.


Solar Cycle 25 is here, says NASA

Posted: September 17, 2020 by oldbrew in Cycles, News, solar system dynamics
Tags: ,

The Sun from NASA’s SDO spacecraft

Solar Cycle 25 has begun, according to this NASA press release.

During a media event on Tuesday, experts from NASA and the National Oceanic and Atmospheric Administration (NOAA) discussed their analysis and predictions about the new solar cycle – and how the coming upswing in space weather will impact our lives and technology on Earth, as well as astronauts in space.

The Solar Cycle 25 Prediction Panel, an international group of experts co-sponsored by NASA and NOAA, announced that solar minimum occurred in December 2019, marking the start of a new solar cycle.


Sunspots [image credit: NASA]

But it should be a lot shorter than the famous Maunder Minimum, if the prediction in this editorial works out. There’s also a new paper, introduced here by the GWPF, which concludes:
“The fundamental oscillations of solar irradiance, in turn, may be linked to the oscillations of the baseline terrestrial temperature, independent of any terrestrial processes of radiative transfer and heating.”

– – –
In this editorial I will demonstrate with newly discovered solar activity proxy-magnetic field that the Sun has entered into the modern Grand Solar Minimum (2020–2053) that will lead to a significant reduction of solar magnetic field and activity like during Maunder minimum leading to noticeable reduction of terrestrial temperature.

Sun is the main source of energy for all planets of the solar system. This energy is delivered to Earth in a form of solar radiation in different wavelengths, called total solar irradiance.

Variations of solar irradiance lead to heating of upper planetary atmosphere and complex processes of solar energy transport toward a planetary surface.

The signs of solar activity are seen in cyclic 11-year variations of a number of sunspots on the solar surface using averaged monthly sunspot numbers as a proxy of solar activity for the past 150 years.

Solar cycles were described by the action of solar dynamo mechanism in the solar interior generating magnetic ropes at the bottom of solar convective zone.

These magnetic ropes travel through the solar interior appearing on the solar surface, or photosphere, as sunspots indicating the footpoints where these magnetic ropes are embedded into the photosphere.

Continued here.
– – –
Appendix 1: S-E distances from the ephemeris

Appendix 2: Solar irradiance variations based on the distance changes

World climate classification map [credit: Beck, H.E., Zimmermann, N. E., McVicar, T. R., Vergopolan, N., Berg, A., & Wood, E. F. @ Wikipedia]

The Homeric seems to have started about 2400 years before the Spörer (or Maunder?) Minimum, which may be its more recent equivalent. Researchers have found evidence of a ‘2400-year cycle in atmospheric radiocarbon concentration’ – for example, see here.

Much of the article below appears to have come from Wikipedia, but there it also says:
“Variations in the solar output have effects on climate, less through the usually quite small effects on insolation and more through the relatively large changes of UV radiation and potentially also indirectly through modulation of cosmic ray radiation. The 11-year solar cycle measurably alters the behaviour of weather and atmosphere, but decadal and centennial climate cycles are also attributed to solar variation.”

– – –
The Homeric Minimum is a grand solar minimum that took place between 2,800 and 2,550 years before present, says the Grand Solar Minimum website.

It appears to coincide with, and have been the cause of, a phase of climate change at that time, which involved a wetter western and drier eastern Europe.

This had far-reaching effects on human civilization, some of which may be recorded in Greek mythology and the Old Testament.


Solar Cycle Update

Posted: July 15, 2020 by oldbrew in Cycles, Solar physics
Tags: ,

SC 25 – are we nearly there yet?

July 14, 2020: NOAA has released a new interactive tool to explore the solar cycle. It lets you scroll back through time, comparing sunspot counts now to peaks and valleys of the past. One thing is clear. Solar Minimum is here, and it’s one of the deepest in a century.


Solar Minimum is a natural part of the solar cycle. Every ~11 years, the sun transitions from high to low activity and back again. Solar Maximum. Solar Minimum. Repeat. The cycle was discovered in 1843 by Samuel Heinrich Schwabe, who noticed the pattern after counting sunspots for 17 years. We are now exiting Solar Cycle 24 and entering Solar Cycle 25.

During Solar Minimum, the sun is usually blank–that is, without sunspots. The solar disk often looks like a big orange billiard ball:

hmi1898 The spotless sun on July 13, 2020

In 2019, the sun went 281 days without sunspots, and…

View original post 245 more words

Ionized gas inside the Sun moves toward the poles near the surface and toward the equator at the base of the convection zone (at a depth of 200,000 km/125,000 miles).
Credit: MPS (Z.-C. Liang)

The title of the study cited in this report gives us the clue: ‘Meridional flow in the Sun’s convection zone is a single cell in each hemisphere’. The full cycle takes about 22 years on average, with a magnetic reversal halfway through.
– – –
The sun’s magnetic activity follows an 11-year cycle. Over the course of a solar cycle, the sun’s magnetic activity comes and goes, says

During solar maximum, large sunspots and active regions appear on the sun’s surface. Spectacular loops of hot plasma stretch throughout the sun’s atmosphere and eruptions of particles and radiation shoot into interplanetary space.

During solar minimum, the sun calms down considerably. A striking regularity appears in the so-called butterfly diagram, which describes the position of sunspots in a time-latitude plot.