Heliogenic Climate Change

“In my articles to date I have been unwilling to claim anything as grand as the creation of a new model of climate because until now I was unable to propose any solar mechanism that could result directly in global albedo changes without some other forcing agent or that could account for a direct solar cause of discontinuities in the temperature profile along the horizontal line of the oceanic thermohaline circulation.  I have now realised that the global albedo changes necessary and the changes in solar energy input to the oceans can be explained by the latitudinal shifts (beyond normal seasonal variation) of all the air circulation systems and in particular the net latitudinal positions of the three main cloud bands namely the two generated by the mid latitude jet streams plus the Inter Tropical Convergence Zone (ITCZ).

The secret lies in the declining angle of incidence of solar energy input from equator to poles.

It is apparent that the same size and density of cloud mass moved, say, 1000 miles nearer to the equator will have the following effects:

i) It will receive more intense irradiation from the sun and so will reflect more energy to space.

ii) It will reduce the amount of energy reaching the surface compared to what it would have let in if situated more poleward.

iii) In the northern hemisphere due to the current land/sea distribution the more equatorward the cloud moves the more ocean surface it will cover thus reducing total solar input to the oceans and reducing the rate of accretion to ocean energy content.

iv) It will produce cooling rains over a larger area of ocean surface.

As a rule the ITCZ is usually situated north of the equator because most ocean is in the southern hemisphere and it is ocean temperatures that dictate it’s position by governing the rate of energy transfer from oceans to air. Thus if the two mid latitude jets move equatorward at the same time as the ITCZ moves closer to the equator the combined effect on global albedo and the amount of solar energy able to penetrate the oceans will be substantial and would dwarf the other proposed effects on albedo from changes in cosmic ray intensity generating changes in cloud totals as per Svensmark and from suggested changes caused in upper cloud quantities by changes in atmospheric chemistry involving ozone which various other climate sceptics propose.

Thus the following NCM will incorporate my above described positional cause of changes in albedo and rates of energy input to the oceans rather than any of the other proposals. That then leads to a rather neat solution to the other theories’ problems with the timing of the various cycles as becomes clear below.”

Read more here:  “A new and effective climate model“

“Abstract: Using kappa Ceti as a proxy for the young Sun we show that not only was the young Sun much more effective in protecting the Earth environment from galactic cosmic rays than the present day Sun; it also had flare and corona mass ejection rates up to three orders of magnitude larger than the present day Sun. The reduction in the galactic cosmic ray influx caused by the young Sun’s enhanced shielding capability has been suggested as a solution to what is known as the faint young Sun paradox, i.e. the fact that the luminosity of the young Sun was only around 75% of its present value when life started to evolve on our planet around four billion years ago [and yet, paradoxically, the Earth didn't freeze over]. This suggestion relies on the hypothesis that the changing solar activity results in a changing influx of galactic cosmic rays to the Earth, which results in a changing low-altitude cloud coverage and thus a changing climate. Here we show how the larger corona mass ejection rates of the young Sun would have had an effect on the climate with a magnitude similar to the enhanced shielding capability of the young Sun.”  “How did the Sun affect the climate when life evolved on the Earth?“  h/t Lubos Motl

“Low-level clouds cover more than a quarter of the Earth and exert a strong cooling effect at the surface.  … Cloud tops have a high albedo and exert their cooling effect by scattering back into the cosmos much of the sunlight that could otherwise warm the surface.

But the snows on the Antarctic ice sheets are dazzlingly white, with a higher albedo than the cloud tops. There, extra cloud cover warms the surface, and less cloudiness cools it.  Satellite measurements show the warming effect of clouds on Antarctica, and meteorologists at far southern latitudes confirm it by observation.  …

The cosmic-ray and cloud-forcing hypothesis therefore predicts that temperature changes in Antarctica should be opposite in sign to changes in temperature in the rest of the world. This is exactly what is observed, in a well-known phenomenon that some geophysicists have called the polar see-saw, but for which “the Antarctic climate anomaly” seems a better name (Svensmark 2007).

To account for evidence spanning many thousands of years from drilling sites in Antarctica and Greenland, which show many episodes of climate change going in opposite directions, ad hoc hypotheses on offer involve major reorganization of ocean currents. While they might be possible explanations for low-resolution climate records, with error-bars of centuries, they cannot begin to explain the rapid operation of the Antarctic climate anomaly from decade to decade as seen in the 20th century (figure 6).

Cloud forcing is by far the most economical explanation of the anomaly on all timescales.  Indeed, absence of the anomaly would have been a decisive argument against cloud forcing – which introduces a much-needed element of refutability into climate science.”  “Cosmoclimatology:  a new theory emerges“  h/t WUWT

Nicola Scafetta has a new paper out, “Climate change and its causes — a discussion about some key issues” (13MB pdf).  It is well worth a read.  One “key issue” is “a large 60 year cycle in the temperature record” (p. 19).  Says Scafetta:

“It has been observed that several multi-secular climatic and oceanic records present large cycles with periods of about 50-70 years with an average of 60 years [18].17 Figure 10 [below] shows the global temperature record detrended of its quadratic upward trend [19] depicted in Figure 1. This sequence has been filtered of its fast fluctuations (by applying a six year moving average smooth algorithm) and it has been plotted against itself with a time-lag of about 60 years. The figure clearly suggests the existence of an almost perfect cyclical correspondence between the periods 1880-1940 and 1940-2000. The peak in 1880 repeats in 1940 and again in 2000. The smaller peak in 1900 repeats in 1960. This 60-odd year oscillation cannot be associated with any known anthropogenic phenomenon [19]. (See also Appendixes Q and R).”

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What causes this 60-year cycle?  Scafetta goes on (p. 22):

“If the temperature is characterized by natural periodic cycles the only reasonable explanation is that the climate system is modulated by astronomical oscillations.20 Natural cycles known with certainty are the 11 (Schwabe) and 22 (Hale) year solar cycles, the cycles of the planets and luni-solar nodal cycles [19,24]. Jupiter has an orbital period of 11.87 years while Saturn has an orbital period of 29.4 years. These periods predict three other major cycles which are associated with Jupiter and Saturn: about 10 years, the opposition of [the] two planets; about 20 years, their synodic cycle; and about 60 years, the repetition of the combined orbits of the two planets. The major lunar cycles are about 18.6 and 8.85 years.

Figure 12 shows a spectral analysis of the global surface temperature and of a record that depends on the orbits of planets (the speed of the sun relative to the center of mass of the solar system [19]). The two records have almost the same cycles. The temperature record contains the cycles of the planets combined with the two solar cycles of 11 and 22 years and a lunar cycle at about 9.1 years.21 (See also Appendixes Q-V).  …

The physical mechanisms involved in the process are likely numerous. The gravitational forces of the planets can partially modulate the solar activity. For example, it was noted that the alignment of Venus, Earth and Jupiter presents cycles of approximately 11 years that are in phase with the 11-year solar cycles [21] and multi secular reconstructions of solar activity reveal 60-year cycles associated with the combined orbit of Jupiter and Saturn and other longer cycles [22]. Solar changes could modulate climate change through various physical and chemical processes as explained in Section 6, which are currently not included in the models, as explained in Section 6.

There is also the possibility that the Earth’s orbital parameters are directly modulated by the gravitational forces of Jupiter, Saturn and the Moon, and the Sun’s magnetic force in such a way that the length of day is modulated and/or other planetary parameters are altered.  For example, the rotation of the Earth on its axis shows 60-year cycles that anticipate those of the temperature by a few years [18, 23]. Variations in the Earth’s rotation and tides caused by the lunar cycles can drive ocean oscillations, which in turn may alter the climate [19]. For example, the Atlantic Multidecadal Oscillation (AMO) and the Pacific Decadal Oscillation (PDO) present clear 60-year cycles and other faster cycles, see Figures 14 and 15. None of these mechanisms are included in the models adopted by the IPCC.”

Prior posts on the Jovian planets’ tidal influence on the Sun here.  Anthony Watts covers the paper here.

“Using the fact that the galactic cosmic ray flux incident on the heliosphere boundary is known to have remained close to constant over the last 200 kyr, and that there exist independent records of geomagnetic variations over this period, Sharma25 was able to use a functional relation reflecting the existing data to give a good estimate of solar activity over this 200 kyr period.  …

Sharma was able to calculate the normalized solar modulation factor over the last 200 kyr. The result is shown in Fig. 8.

The 100 kyr periodicity is readily apparent in Fig. 8. It is also seen that the d18O record and solar modulation are coherent and in phase. Sharma concludes from this that “. . . variations in solar surface magnetic activity cause changes in the Earth’s climate on a 100-ka timescale”.  …

Summary

It has been shown above that low altitude cloud cover closely follows cosmic ray flux; that the galactic cosmic ray flux has the periodicities of the glacial/interglacial cycles; that a decrease in galactic cosmic ray flux was coincident with Termination II [the warming that initiated the Eemian, the last interglacial] ; and that the most likely initiator for Termination II was a consequent decrease in Earth’s albedo.

The temperature of past interglacials was higher than today most likely as a consequence of a lower global albedo due to a decrease in galactic cosmic ray flux reaching the Earth’s atmosphere. In addition, the galactic cosmic ray intensity exhibits a 100 kyr periodicity over the last 200 kyr that is in phase with the glacial terminations of this period. Carbon dioxide appears to play a very limited role in setting interglacial temperature.”  “INTERGLACIALS, MILANKOVITCH CYCLES, AND CARBON DIOXIDE“  h/t Niche Modeling

h/t Chiefio

A new paper by Qing-Bin Lu of the University of Waterloo is making quite a splash (see e.g. WUWT). The paper purports to show that solar-magnetic-field-modulated cosmic rays are responsible not only for the Antarctic “ozone hole” (see prior paper by Lu here) but also for recent climate change through a mechanism involving cosmic rays and chlorofluorcarbons (CFCs) described in the abstract as follows:

“The cosmic-ray driven electron-induced reaction of halogenated molecules adsorbed on ice surfaces has been proposed as a new mechanism for the formation of the polar ozone hole. Here, experimental findings of dissociative electron transfer reactions of halogenated molecules on ice surfaces in electron-stimulated desorption, electron trapping and femtosecond time-resolved laser spectroscopic measurements are reviewed. It is followed by a review of the evidence from recent satellite observations of this new mechanism for the Antarctic ozone hole, and all other possible physical mechanisms are discussed. Moreover, new observations of the 11 year cyclic variations of both polar ozone loss and stratospheric cooling and the seasonal variations of CFCs and CH₄ in the polar stratosphere are presented, and quantitative predictions of the Antarctic ozone hole in the future are given. Finally, new observation of the effects of CFCs and cosmic-ray driven ozone depletion on global climate change is also presented and discussed.”

I don’t think the paper adequately explains recent climate change however, primarily because I don’t think CFCs are primarily responsible for the Antarctic “ozone hole”. I think the observed correlation of cosmic rays and the Antarctic “ozone hole” has a much simpler explanation. For a good discussion of the latter issues see the article at Junk Science.
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“As I understand it, the [geomagnetic] Ap index is believed to be related to the level of cosmic ray activity reaching the Earth [which is modulated by the solar magnetic field]. …

If we do a scatterplot of the data (below), we get an average linear relationship of about 0.05 W per sq. meter increase in reflected sunlight per 1 unit decrease in Ap index. This is at least qualitatively consistent with a decrease in solar activity corresponding to an increase in cloud cover. …

But just how big is this linear relationship seen in the above scatterplot? From looking at a 70-year plot of Ap data (originally from David Archibald), we see that the 11-year sunspot cycle modulates the Ap index by at least 10 units. …

When the 10 Ap unit variations are multiplied by the 0.05 scale factor, it suggests about a 0.5 W per sq. meter modulation of global reflected sunlight during the 11 year solar cycle (as well as in monthly and yearly variations of geomagnetic activity). I calculate that this is a factor of 10 greater than the change in reflected sunlight that results from the 0.1% modulation of the total solar irradiance [TSI] during the solar cycle.

At face value, that would mean the geomagnetic [solar] modulation of cloudiness has about 10 times the effect on the amount of sunlight absorbed by the Earth as does the solar cycle’s direct modulation of the sun’s output.” “Geomagnetic Forcing of Earth’s Cloud Cover During 2000-2008?“
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“CERN’s much-anticipated CLOUD experiment has begun, the atom lab says. Using the 50-year-old Proton Synchrotron, the experiment simulates cosmic rays passing through the earth’s atmosphere, and hopes to reveal the extent to which the constant background drizzle of charged particles plays a role in cloud formation. Earlier experiments have suggested that ionisation causes clouds to “seed” – and that ionisation is influenced by the type and quantity of cosmic rays that reach the earth.

Both the sun and the earth’s magnetic fields act as umbrellas, protecting the surface from the high energy particles, although two particles still reach the surface per second. But small changes in the cosmic ray flux produce significant changes in cloud cover. When fewer cosmic rays reach earth, the planet’s climate is warmer, when more reach earth, the climate cools.

“So marked is the response to relatively small variations in the total ionization, we suspect that a large fraction of Earth’s clouds could be controlled by ionisation,” noted Danish scientist Henrik Svesmark this summer. Svensmark has pioneered the research using smaller experiments, but has waited over a decade to see it tested on such a scale.

Much of the recent interest comes from climate watchers. Clouds are one of the biggest factors in determining global surface temperature, but the UN’s IPCC admits the level of scientific understanding of them is poor.

The cosmic ray effect – a factor of the background CBR [cosmic background radiation] bombardment itself, and the relative strength of the earth and the Sun’s magnetic shields – shows a strong correlation between temperature [and] CBR and is extraordinary. Here’s the relationship over the short term – around 2,000 years.

And here’s the correlation into deep time, with CO2 as a comparison.

In addition, “deep freezes” in the Earth’s temperatures have coincided with short-lived but intense bursts of cosmic ray activity. Modulation is thought to reflect the Sun’s passage through spiral arms of the Milky Way, and also the Sun’s oscillation in relation to the plane of the galaxy. The Sun bobs up and down 2.7 times per orbit.” “CERN’s cosmic cloudmaker cranks up — May solve climate mystery, Thermageddon scare” h/t Greenie Watch

“Sustained drops in the energy output of the Sun could be more common than modern experience suggests, according to an international team of astronomers that has studied the activity of a number of Sun-like stars. The results could mean that past changes in global temperatures are more likely to be related to variations in solar activity than previously thought, and could allow us to predict similar changes in future. …

In 2006 Mark Giampapa of the National Solar Observatory, Arizona, and colleagues used the Very Large Telescope (VLT) in Chile to measure the activity levels of 60 stars in the M67 galactic cluster – nearly 3000 light-years away. “M67 is an ideal solar laboratory in the sense that it has the same age as the Sun and virtually identical chemical abundances,” Giampapa told physicsworld.com.

Sunspots cannot be observed directly on distant stars, so the team focused on certain emission lines in the spectra of light emitted by the stars. The width of these lines can be related to the level of magnetic activity in the star, allowing the team to conclude that 7–12% of the stars exhibited activity beyond a typical solar maximum and 17% were below a typical solar maximum. …

The low activity levels cannot be so easily explained and might represent a typical feature in the activity of a Sun-like star. One well documented example of such a period of unusual solar quiescence was the Maunder Minimum of the 17th century, when a significant drop in sunspot numbers coincided with a recorded drop in global temperatures. If Giampapa’s research rings true, it could mean that the Sun spends a significant amount of its time in a Maunder Minimum-like state – and it might reveal how likely we are to experience such periods of cooling in the future. …

The research has been accepted for publication in Astrophysical Journal.” “Distant stars shed light on the solar cycle“
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Desmoulins graph: green peaks = JEV most aligned days.

“The Sunspot cycle which averages 11 years is still a mystery, with no real conclusive science that has been put forward with any certainty on what controls the varying length of the Sunspot cycle.

Previously in my Neptune/Uranus article we discussed the work of Desmoulins who has graphed the “most aligned days” of Jupiter, Earth and Venus which shows a good correlation with the sunspot record. The two sets of data can drift away slightly but have always kept in sync in the last 400 years. Currently The most aligned days is lagging behind the Sunspot record slightly and going by past occurrences should catch up during SC24 max. Hung as also done some similar research showing the same result as well as Ulric Lyons who presented his case on this blog last year.

Now we have another study by G.E.Pease which backs up this previous work and provides many diagrams and tables to support the Planet Tidal Theory. The presentation is in powerpoint format and can be downloaded HERE.” “Sunspot cycle phasing with conjunctions of Jupiter and inner planets” Prior posts here and here.

“Note the inverse relationship of cosmic rays (blue) and sunspots (orange) and how low clouds in different latitude bands increase during solar minima when cosmic rays increase and decrease during solar maxima when cosmic rays are diffused.” “Dalton like Solar Minimum – Back to the Age of Dickens?“
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As of the end of October, the cumulative number of spotless days (days without sunspots) in the transition into solar cycle 24 now stands at 745. The transitions into Solar Cycles 16-23, referred to as “recent solar cycles” (years 1923 to ~2008), averaged 362 cumulative spotless days (with a range from 227 to 568 spotless days). Since the current transition now exceeds 568 spotless days, it is very clear that the sun has undergone a state change. The solar “Grand Maxima” state that has persisted during most of the 20th century has come to an abrupt end. The “old solar cycles” (SC 10-15, years 1856 to 1923) averaged 797 spotless days, over twice that of the “recent solar cycles”. Those solar cycle minimums ranged from 406 – 1028 spotless days. If this solar minimum ends soon then the upcoming solar cycle may be similar to these “old solar cycles”.

So far the sun continues to be fairly quiet. This solar minimum acts like the Energizer bunny. It just keeps going, and going, and going.

The Average Magnetic Planetary Index (Ap index) is a proxy measurement for the intensity of solar magnetic activity as it alters the geomagnetic field on Earth. It has been referred to as the common yardstick for solar magnetic activity. An Ap index of “4″ was the lowest recorded monthly value since measurements began in January 1932.

Back in January 2009, David Archibald predicted the Ap index would hit a low in October 2009 with a value of “3”. Analysis from past solar cycles shows that the Ap index generally reaches its lowest value approximately a year after the solar sunspot minimum. So the question is how well did he do.

The Ap Index for last month, October, was “2″ [correction: "3"]. That is really close in my book. The Ap index had been hovering near rock bottom for 11 months now. Beginning in November 2008, there have been 8 monthly readings of “4″ along with 3 monthly readings of “5″. But this month the value broke through the glass ceiling and spawned the lowest AP monthly index value in the past 77 years. So with this transition into solar cycle 24, all the AP monthly records have been broken. The lowest single month value, two consecutive month value, three consecutive month value, etc. All of those records have fallen, swept away in this solar state change.

So what does this all mean? Well, the sun’s interplanetary magnetic field has fallen to around 4 nT (nano Tesla) from a typical value of 6 to 8 nT. The solar winds pressure is down to 50 year lows. And the heliospheric current sheet is flattening. All these changes allow high-energy galactic cosmic rays to penetrate deeper into our solar system. In 2009, cosmic ray intensities have increased 19% beyond anything we’ve seen in the past 50 years, when satellite measurements began. Greater numbers of galactic cosmic rays driving deep into our atmosphere cause greater cloud formation (through ionization) which then results in decreasing surface temperature on Earth. This is because low level clouds reflect sunlight back into space. This is why Northern and Southern hemispheres have experienced unusually cold winters during the past couple years. The influence of the sun’s magnetic field is a force to be reckoned with in natural climate change.

The sun exhibits great variability in the strength of each solar cycle. This variability ranges from extremely quiet “Grand Minima” such as the Maunder Minimum to a very active “Grand Maxima” such as the enhanced activity observed during most of the 20th century. A solar Grand Minima is defined as a period when the (smoothed) sunspot number is less than 15 during at least two consecutive decades. The sun spends about 17 percent of the time in a Grand Minima state. In the past, these periods caused great hardship to humanity and significant loss of life.

Solar Grand Minima events correspond to periods of dramatic natural global cooling. The Maunder Minimum (about 1645-1715 A.D.) and Spörer Minimum (about 1420-1570 A.D.) are two examples of recent “Grand Minima” events and each period has been referred to as a Little Ice Age. During the “Grand Minima” galactic cosmic ray fluxes were at least 200% to 300% higher than anything measured to date.

So each morning I turn on my computer and check to see how the sun is doing. Most days I am still greeted with the message “The sun is blank – no sunspots.”

James A. Marusek” From CCNet 3 November
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Svensmark’s new paper (prior posts here and here) has been published (full text here). From Science Daily:

“Averaging satellite data on the liquid-water content of clouds over the oceans, for the five strongest Forbush decreases from 2001 to 2005, the DTU team found a 7 per cent decrease, as mentioned earlier. That translates into 3 billion tonnes of liquid water vanishing from the sky. The water remains the-re in vapour form, but unlike cloud droplets it does not get in the way of sunlight trying to warm the ocean. After the same five Forbush decreases, satellites measuring the extent of liquid-water clouds revealed an average reduction of 4 per cent. Other satellites showed a similar 5 per cent reduction in clouds below 3200 metres over the ocean.

“The effect of the solar explosions on the Earth’s cloudiness is huge,” Henrik Svensmark comments. “A loss of clouds of 4 or 5 per cent may not sound very much, but it briefly increases the sunlight reaching the oceans by about 2 watt per square metre, and that’s equivalent to all the global warming during the 20th Century.”

The Forbush decreases are too short-lived to have a lasting effect on the climate, but they dramatize the mechanism [the Svensmark effect] that works more patiently during the 11-year solar cycle. When the Sun becomes more active, the decline in low-altitude cosmic radiation is greater than that seen in most Forbush events, and the loss of low cloud cover persists for long enough to warm the world. That explains, according to the DTU team, the alternations of warming and cooling seen in the lower atmosphere and in the oceans during solar cycles.

The director of the Danish National Space Institute, DTU, Eigil Friis-Christensen, was co-author with Svensmark of an early report on the effect of cosmic rays on cloud cover, back in 1996. Commenting on the latest paper he says, “The evidence has piled up, first for the link between cosmic rays and low-level clouds and then, by experiment and observation, for the mechanism involving aerosols. All these consistent scientific results illustrate that the current climate models used to predict future climate are lacking important parts of the physics”.” “Cosmic Ray Decreases Affect Atmospheric Aerosols And Clouds“

“According to sensors on NASA’s ACE (Advanced Composition Explorer) spacecraft, galactic cosmic rays have just hit a Space Age high.

“In 2009, cosmic ray intensities have increased 19% beyond anything we’ve seen in the past 50 years,” says Richard Mewaldt of Caltech. …

The cause of the surge is solar minimum, a deep lull in solar activity that began around 2007 and continues today. Researchers have long known that cosmic rays go up when solar activity goes down. Right now solar activity is as weak as it has been in modern times, setting the stage for what Mewaldt calls “a perfect storm of cosmic rays.”

“We’re experiencing the deepest solar minimum in nearly a century,” says Dean Pesnell of the Goddard Space Flight Center, “so it is no surprise that cosmic rays are at record levels for the Space Age.” …

“At times of low solar activity, this natural shielding [by the Sun's magnetic field] is weakened, and more cosmic rays are able to reach the inner solar system,” explains Pesnell.

Mewaldt lists three aspects of the current solar minimum that are combining to create the perfect storm:

1. The sun’s magnetic field is weak. “There has been a sharp decline in the sun’s interplanetary magnetic field (IMF) down to only 4 nanoTesla (nT) from typical values of 6 to 8 nT,” he says. “This record-low IMF undoubtedly contributes to the record-high cosmic ray fluxes.”

2. The solar wind is flagging. “Measurements by the Ulysses spacecraft show that solar wind pressure is at a 50-year low,” he continues, “so the magnetic bubble that protects the solar system is not being inflated as much as usual.” A smaller bubble gives cosmic rays a shorter-shot into the solar system. Once a cosmic ray enters the solar system, it must “swim upstream” against the solar wind. Solar wind speeds have dropped to very low levels in 2008 and 2009, making it easier than usual for a cosmic ray to proceed.
3. The current sheet is flattening. Imagine the sun wearing a ballerina’s skirt as wide as the entire solar system with an electrical current flowing along the wavy folds. That is the “heliospheric current sheet,” a vast transition zone where the polarity of the sun’s magnetic field changes from plus (north) to minus (south). The current sheet is important because cosmic rays tend to be guided by its folds. Lately, the current sheet has been flattening itself out, allowing cosmic rays more direct access to the inner solar system.

“If the flattening continues as it has in previous solar minima, we could see cosmic ray fluxes jump all the way to 30% above previous Space Age highs,” predicts Mewaldt. …

Hundreds of years ago [the Little Ice Age], cosmic ray fluxes were at least 200% higher than they are now. Researchers know this because when cosmic rays hit the atmosphere, they produce an isotope of beryllium, 10Be, which is preserved in polar ice.” “Cosmic Rays Hit Space Age High“
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“This is the first time Angular Momentum Disturbance Strength has been quantified and is depicted by the purple line in the above graph. This purple line shows how Angular Momentum Disturbance Strength is the driver of solar downturns, it is the background curve of the proxy records.” “Angular momentum disturbance strength” Prior posts on solar spin-orbit coupling here
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“[Abstract]: One of the mysteries regarding Earth’s climate system response to variations in solar output is how the relatively small fluctuations of the 11-year solar cycle can produce the magnitude of the observed climate signals in the tropical Pacific associated with such solar variability. Two mechanisms, the top-down stratospheric response of ozone to fluctuations of shortwave solar forcing and the bottom-up coupled ocean-atmosphere surface response, are included in versions of three global climate models, with either mechanism acting alone or both acting together. We show that the two mechanisms act together to enhance the climatological off-equatorial tropical precipitation maxima in the Pacific, lower the eastern equatorial Pacific sea surface temperatures during peaks in the 11-year solar cycle, and reduce low-latitude clouds to amplify the solar forcing at the surface.

[Text]: It has long been noted that the 11-year cycle of solar forcing is associated with variousphenomena in Earth’s climate system, in both the troposphere and stratosphere (1–9). Because the amplitude of the solar cycle (solar maximum to solar minimum) is relatively small, about 0.2 W m−2 globally averaged (10), and the observed global sea surface temperature (SST) response of about 0.1°C would require more than 0.5Wm−2 (11), there has always been a question regarding how this small solar signal could be amplified to produce a measurable response.

Postulated mechanisms that could amplify the relatively small solar forcing signal to produce such responses in the troposphere include changes in clouds in the troposphere caused by galactic cosmic rays, or associated global atmospheric electric circuit variations, though neither has been plausibly simulated in a climate model. However, there are two other plausible mechanisms, though each has not yet produced a modeled response of the magnitude seen in the observations.

The first involves a “top down” response of stratospheric ozone to the ultraviolet (UV) part of the solar spectrum that varies by a few percent. Peaks in solar forcing cause the enhanced UV radiation, which stimulates additional stratospheric ozone production and UV absorption, thus warming that layer differentially with respect to latitude. The anomalous temperature gradients provide a positive feedback through wave motions to amplify the original solar forcing. The changes in the stratosphere modify tropical tropospheric circulation and thus contribute to an enhancement and poleward expansion of the tropical precipitation maxima (5, 12–16). The first demonstration of the top-down mechanism in a modeling study showed a broadening of the Hadley cells in response to enhanced UV that increased as the solar-induced ozone change was included (17).

A second “bottom up” mechanism that can magnify the response to an initially small solar forcing involves air-sea coupling and interaction with incoming solar radiation at the surface in the relatively cloud-free areas of the subtropics. Thus, peaks in solar forcing produce greater energy input to the ocean surface in these areas, evaporating more moisture, and that moisture is carried by the trade winds to the convergence zones where more precipitation occurs. This intensified precipitation strengthens the Hadley and Walker circulations in the troposphere, with an associated increase in trade wind strength that produces greater equatorial ocean upwelling and lower equatorial SSTs in the eastern Pacific, a signal that was first discovered in observational data (1, 2). The enhanced subsidence produces fewer clouds in the equatorial eastern Pacific and the expanded subtropical regions that allow even more solar radiation to reach the surface to produce a positive feedback (18, 19). Dynamical air-sea coupling produces a transition to higher eastern equatorial SSTs a couple of years later (20, 21). There is observational evidence for a strengthened Hadley circulation in peak solar forcing years associated with intensified tropical precipitation maxima, a stronger descending branch in the subtropics, and a stronger ascending branch in the lower latitudes (3); a poleward expansion of the Hadley circulation in peak solar years, with stronger ascending motions at the edge of the rising branch, as well as a stronger Walker circulation with enhanced upward motions in the tropical western Pacific connected to stronger descending motions in the tropical eastern Pacific (7); and enhanced summer season off-equatorial climatological monsoon precipitation over India (6, 22). This cold event– like response to peak solar forcing is different from cold events (also known as La Niña events) in the Southern Oscillation in that, among other things, zonal wind anomalies in the stratosphere are opposite in sign (23).” “Amplifying the Pacific Climate System Response to a Small 11-Year Solar Cycle Forcing” Article in Space.com. Article in ScienceDaily. Article in Christian Science Monitor. Editorial at SEPP. h/t IceCap
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“Attempting a forecast of climate change: An astronomical gravitational forcing for the Sun and the Earth? Presented by Scafetta, at AGU fall meeting 2008” (pp. 62-67) h/t Jeff Id
Prior posts on solar spin-orbit coupling here
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“A team of researchers says it has largely put to rest a long debate on the underlying mechanism that has caused periodic ice ages on Earth for the past 2.5 million years – they are ultimately linked to slight shifts in solar radiation caused by predictable changes in Earth’s rotation and axis.

In a publication to be released Friday in the journal Science, researchers from Oregon State University and other institutions conclude that the known wobbles in Earth’s rotation caused global ice levels to reach their peak about 26,000 years ago, stabilize for 7,000 years and then begin melting 19,000 years ago, eventually bringing to an end the last ice age.

The melting was first caused by more solar radiation, not changes in carbon dioxide levels or ocean temperatures, as some scientists have suggested in recent years.

“Solar radiation was the trigger that started the ice melting, that’s now pretty certain,” said Peter Clark, a professor of geosciences at OSU. “There were also changes in atmospheric carbon dioxide levels and ocean circulation, but those happened later” …

“We now know with much more certainty how ancient ice sheets responded to solar radiation, and that will be very useful in better understanding what the future holds,” Clark said. “It’s good to get this pinned down.” …

Sometime around now, scientists say, the Earth should be changing from a long interglacial period that has lasted the past 10,000 years and shifting back towards conditions that will ultimately lead to another ice age …” “Long debate ended over cause, demise of ice ages – may also help predict future“

“Recall that cosmoclimatology of Henrik Svensmark and others postulates that the galactic cosmic rays are able to create “seeds” of low-lying clouds that may cool the Earth’s surface. A higher number of cosmic rays can therefore decrease the temperature. The creation of the cloud nuclei is caused by ionization and resembles the processes in a cloud chamber. …

The fluctuations of the cosmic ray flux may occur due to the variable galactic environment as well as the solar activity: a more active Sun protects us from a part of the cosmic rays. It means that a more active Sun decreases the amounts of low-lying clouds, which means that it warms the Earth.

Because the low-lying clouds remove 30 Watts per squared meter in average (over time and the Earth) or so, one has to be very careful not only about the very existence of the clouds but also about the variations of cloudiness by 5% or so which translates to a degree of temperature change.

A systematic effect on the clouds – e.g. one of the cosmic origin – is a nightmare for the champions of the silly CO2 toy model of climatology because the cloud variations easily beat any effect of CO2. …

Svensmark and his collaborators have looked at 26 Forbush events since 1987 (those that were strong according to their impact on the spectrum seen in the low troposphere where it matters): most of them occur close to the solar maxima (in the middle of the 11-year cycles). The observations with a much better temporal resolution imply that the mass of water stored in clouds decreases by 4-7%, with the minimum reached after a nearly 1-week delay needed for the cloud nuclei to get mature. Roughly three billions of tons of water droplets suddenly disappear from the atmosphere (they remain there as vapor, which is more likely to warm the air than to cool it down).

An independent set of measurements has also shown that the amount of aerosols, i.e. potential nuclei of the new clouds, also decreases. All these “strength vs decrease” graphs display a lot of noise but the negative slopes are almost always significant at the 95% level (with one dataset being an exception, at 92%, which is still higher than the official IPCC confidence level that climate change is mostly man-made).

Each Forbush decrease can therefore warm up the Earth by the same temperature change as the effect of all carbon dioxide emitted by the mankind since the beginning of the Industrial Revolution. While you might think that such an effect is temporary and lasts a few weeks only, it is important to notice that similar variations in the solar activity, the solar magnetic field, and the galactic cosmic rays take place at many different conceivable frequencies, so there are almost certainly many effects whose impact on the temperature – through the clouds – is at least equal to the whole effect of man-made carbon dioxide.” “Forbush events confirm cosmoclimatology” [prior post here]
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