WUWT’s resident solar expert Dr. Leif Svalgaard (and others) says ‘None of us alive have ever seen such a weak cycle’ and the panel he was on talk about the current state of our solar cycle at the AGU Fall Meeting.
Here is Dr. Svalgaard’s current SSN plot:
Watch the video, Leif is on the left hand side.
At this year’s Fall Meeting of American Geophysical Union, held in San Francisco that I attended, prominent solar scientists made a presentation on weak Solar Cycle 24 and its consequences. They included:
- Nat Gopalswamy, astrophysicist, Solar Physics Laboratory, NASA Goddard Space Flight Center, Greenbelt, Maryland
- Leif Svalgaard, senior research scientist, W. W. Hansen Experimental Physics Laboratory, Stanford University, Stanford, California
- Marty Mlynczak, senior research scientist, Climate Science Branch, NASA Langley Research Center, Hampton, Virginia
- Joe Giacalone, professor and associate director, Lunar and Planetary Laboratory, University of Arizona, Tucson, Arizona
They agreed that the current solar cycle is on track to be the weakest in 100 years and that is an unprecedented opportunity for studying the Sun during this period. While the weak solar cycle trend is not new for the Sun, it is new and interesting for scientists who observe and measure it today with modern instruments and methods.
In this panel, scientists examined the current solar cycle in relation to past cycles and discuss the consequences of the weak solar cycle on the various layers regions between the Sun and Earth, including implications for space weather, atmosphere and climate.
Here is part of the press release package:
Solar signatures and Heliospheric Consequences of the Weak Activity Cycle 24
Nat Gopalswamy, NASA Goddard Space Flight Center, Greenbelt, MD 20771,
The Sun in the middle of its activity maximum that is relatively weak. The maximum phase ended in the northern hemisphere of the Sun and began about a year ago in the south.
The weak activity of cycle 24 is thought to be due to the weak polar magnetic field in cycle 23. If this trend continues for the next couple of cycles, the Sun may be heading for a global minimum.
Whether global minimum or not, the weak solar cycle has resulted in milder space weather: there are not many large geomagnetic storms and the energetic particle events are also generally of lower intensity. The milder space weather also reduces the drag on satellites and it is easy to keep them in orbit. On the other hand the space debris also have longer life, posing increased collision threat to operating satellites.
The weak solar activity in terms of the sunspot number did not quite translate into the CME rate itself. The CME occurrence rate in cycles 24 and 23 are comparable in the maximum phase. Then how do we understand the mild space weather in cycle 24?
A clue to the reason for milder space weather came from the fact that all CMEs that produced particle events are halo CMEs in cycle 24, compared to about 70% in cycle 23. Halo CMEs originate from close to the disk center and expand rapidly and give the appearance of surrounding the Sun. There must be something different about the size of the CMEs in SC 24.
Gopalswamy and co-‐workers examined the relation between CME width and speed and found that the cycle 24 CMEs are wider than the cycle 23 ones for a given speed. For energetic CMEs (speed exceeding 1000 km/s), the width is higher by about 40%.
When they examined the total pressure (magnetic pressure + plasma pressure) in the heliosphere from measurements made by spacecraft such as ACE and Wind, they found that the pressure decreased by an astonishing 40% in cycle 24. From this they inferred that the pressure must drop by a similar amount near the Sun. CMEs released into this low-‐pressure medium, expand more than usual, resulting in weaker fields, and hence weaker geomagnetic storms. The magnetic field strength in CMEs decides the intensity of geomagnetic storms.
As far the particle radiation, the situation is a bit more complicated. The reduced total pressure means a slight increase in the Alfven speed in the heliosphere. The Alfven speed is the characteristic speed of the medium. A CME needs to be faster than the Alfven speed to drive a shock that accelerates particles.
Therefore, it is slightly easier for the cycle 24 CMEs to drive shocks. However, the shocks are propagating through a medium of reduced magnetic field, which is known to be less conducive for accelerating particles to high energies. This means the number of particle events is not very low, but the events are generally of lower intensity and energy.
Here are other parts of the press release. Source: AGU
Historical geological data shows that there were major volcanic eruptions [level 5 and higher] during past solar minimums or cooler periods. There were 10 major eruptions during Maunder minimum [1640-1721], 3 during Dalton Minimum 1790-1822 and 6 during the 1880-1910 Minimum. These eruptions included major eruptions like Long Island , level 6 in 1660, Krakatau, level 6 in 1883, Tambora ,level 7 in 1815, Santa Maria ,level 6 in 1902 and Novarupta ,level 6 in 1912 Volcanic ash and other suspended particles tend to block out the earth’s sunlight, thus reducing solar radiation and lowering mean global temperatures for up to 5 years as we saw with the Krakatau eruption in 1883.
Oh my goodness can we not talk about variations in climate without going to the sky is falling extremes.. it gets warmer.. the sky falls, it might get cooler.. the sky falls. I have to tell you Im getting really sick of worst case scenario legislation.
Good article though! Such a big leap from nothing to see here move along:)
In reply to: beng says: December 14, 2013 at 6:34 am
***
William Astley says: December 14, 2013 at 4:26 am
Bing says: Unnecessary to invoke solar “explanations” for D/O events. Ice-sheet dynamics (particularly at the restriction between Greenland & Iceland which can clog the Fram Straight) are sufficient:
William:
The silly suggestion – it is not even a hypothesis as there is no mechanism to explain how ‘ice-sheet dynamics’ can simultaneously affect both hemispheres was disproved 20 years ago. There is not even a back of the envelope calculation to explain what the heck causes the ice sheets to suddenly cyclically change and there is no calculation or even a couple of paragraph explanation as to how a change to the ice sheets could possibly cause both hemispheres to warm and then to cool. Get real. The bing/purge suggestion is at least 20 years old. It failed due to my comments and due to the fact that during the glacial period geographically disconnected ice sheets suddenly all start to change which requires a global forcing mechanism i.e. duh the sun. There are cosmogenic isotopes changes at each and every climate change event. The cosmogenic isotope changes are caused by solar magnetic cycle changes. The scientific problem is not if solar magnetic cycle changes cause cyclic climate change, including the massive climate forcing change a Heinrich event that is capable and that has terminated past interglacial periods.
I find it surreal that we are having this thread discussion as it is obvious from observations, that the solar magnetic cycle has been interrupted. We have started to experience the first observed cooling (UV radiation has dropped by 20%, the solar heliosphere pressure has dropped by 40%, GCR levels at the peak of solar magnetic cycle 24 are the same as the average levels in past cycles).
Unequivocal significant cooling (reversing of the warming in the last 70 years and a return Little Ice age temperatures before the Heinrich event) is only possible if the majority of the warming in the last 70 was cause by solar magnetic cycle modulation of planetary cloud cover.
The pattern of warming in the last 70 years does not match the predicted pattern of warming if CO2 was the forcing mechanism. As shown in Bob Tisdale’s graph, temperature anomaly, land and ocean, average 2007 to December, 2012 by latitude, the majority of the warming in the last 70 years was in high latitude regions rather than in the tropics. That observation contradicts what the IPCC model predicted. The IPCC models predicted that the majority of the warming should be in the tropics where the most amount of long wave (infrared radiation is emitted to space).
http://bobtisdale.files.wordpress.com/2013/11/figure-72.png
As CO2 is more or less evenly distributed in the atmosphere the potential for CO2 warming is the same for all latitudes. The actual warming due to CO2 is linearly dependent on the amount of long wave radiation at the latitude in question that is emitted to space before the increase in CO2. As the most amount of long wave radiation that is emitted to space is in the tropics the most amount of warming due to the CO2 increase should have occurred in the tropics. That is not what is observed. The following is a peer reviewed paper that supports the above assertions.
http://arxiv.org/ftp/arxiv/papers/0809/0809.0581.pdf
“These effects do not have the signature associated with CO2 climate forcing. (William: This observation indicates something is fundamental incorrect with the IPCC models, likely negative feedback in the tropics due to increased or decreased planetary cloud cover to resist forcing). However, the data show a small underlying positive trend that is consistent with CO2 climate forcing with no-feedback. (William: This indicates a significant portion of the 20th century warming has due to something rather than CO2 forcing.)”
Reblogged this on The Next Grand Minimum and commented:
Weak solar cycles have been associated with Grand Minimums and cooler temperatures. Are we on the cusp of our next Grand Minimum?
pkatt says:
December 14, 2013 at 11:10 am
Oh my goodness can we not talk about variations in climate without going to the sky is falling extremes.. it gets warmer.. the sky falls, it might get cooler.. the sky falls. I have to tell you Im getting really sick of worst case scenario legislation.
______
Yes, but.. now we see how it falls ( goes up and down) and that’s the fun part. Let that other stuff just go..
Read it slow it’s a mouth full.. (SWS solar wind speeds)
Effects on winter circulation of short and long term solar wind changes
Limin Zhoua, Brian Tinsleyb, Jing Huanga
http://www.sciencedirect.com/science/article/pii/S0273117713005802
Available online 21 September 2013
“””The spatial distribution of the correlations of geopotential height changes in the troposphere and stratosphere with the SWS; the geo-effective electric field (SWS∗Bz); and the solar 10.7 cm flux suggests that solar wind inputs connected to the troposphere via the global electric circuit, together with solar ultraviolet irradiance acting on the stratosphere, affect regional atmospheric dynamics.””””
Day-to-day changes in the Arctic and North Atlantic Oscillations correlate with solar wind speed and relativistic electron precipitation.
Interannual changes are similarly correlated.
A connection via the global atmospheric electric circuit and cloud microphysical changes is suggested.””
And the flux of whatever else coming down..
Puts a whole new or another “Twist” on the following video clip..
Apologies for the typo in the first sentence and for the long time it took to get corrected. I was dead tired when I wrote that post, even though it was only 8PM. The week at AGU took its toll on me and my typing suffered. After 10 hours of sleep, I’m somewhat normal again. – Anthony
Once the maximum of solar cycle 24 ends the solar /climate connections should become more clear. I list possible solar mechanisms and solar criteria ,below.
SOLAR CLIMATE MECHANISMS AND CLIMATE PREDICTION
MECHANISM ONE
One solar climate mechanism/connection theory which has much merit in my opinion, is as follows:
A BRIEF OVERVIEW. At times of low solar irradiance the amounts of sea ice in the Nordic Sea increase, this ice is then driven south due to the atmospheric circulation (also due to weak solar conditions) creating a more northerly air flow in this area.(-NAO) This sea ice then melts in the Sub Polar Atlantic, releasing fresh water into the sub- polar Atlantic waters, which in turn impedes the formation of NADW, which slows down the thermohaline circulation causing warm air not to be brought up from the lower latitudes as far north as previous while in lessening amounts.
This perhaps can be one of the contributing solar/climate connection factors which brought about previous abrupt N.H. cool downs during the past.
This makes much sense to me.
NAO= NORTH ATLANTIC OSCILLATION
NADW= NORTH ATLANTIC DEEP WATER
To elaborate on the above, when the sun enters a prolonged solar minimum condition an overall reduction takes place in solar spectral irradiance, namely in UV light (wavelengths less then 400 nm). The shorter the wavelength, the MUCH greater the reduction.
UV light reduction likely will cause ocean heat content and ocean surface temperatures to drop, due to the fact that UV light in the range of 280 nm-400nm penetrates the ocean surface to depths of 50-100 meters. A reduction in UV (ultra violet) light then should have a profound effect on the amount of energy entering the ocean surface waters from the sun extending down to 50-100 meters in depth, resulting in cooler ocean temperatures.
This ties into what was said in the above in that if ocean waters in high latitudes such as the Nordic Sea, were to be subject to cooling the result would be much more sea ice which could impede the strength of the thermohaline circulation promoting substantial N.H. cooling.
Adding to this theory is fairly strong evidence that a decrease in UV light will result in a more meridional atmospheric circulation (which should cause more clouds, precipitation and snow cover for the N.H.), due to changes in ozone distribution in a vertical/horizontal sense which would cause the temperature contrast between the polar areas of the stratosphere and lower latitude areas of the stratosphere to lesson, during prolonged solar minimum periods. Ultra Violet light being likely the most significant solar factor affecting ozone concentrations ,although not the only solar factor.
This could then set up a more -NAO, (high pressure over Greenland) which would promote a more Northerly flow of air over the Nordic Sea, bringing the sea ice there further South.
MECHANISM TWO
A reduction of the solar wind during a prolonged solar minimum event would cause more galactic cosmic rays to enter the earth’s atmosphere which would promote more aerosol formation thus more cloud nucleation. The result more clouds higher albedo, cooler temperatures.
Compounding this would be a weaker geo magnetic field which would allow more galactic cosmic ray penetration into the atmosphere , while perhaps causing excursions of the geo magnetic poles to occur in that they would be in more southern latitudes concentrating incoming galactic cosmic rays in these southern latitudes where more moisture would be available for the cosmic rays to work with, making for greater efficiency in the creation of clouds.
MECHANISM THREE
MILANKOVITCH CYCLES overall favor N.H. cooling and an increase in snow cover over N.H high latitudes during the N.H summers due to the fact that perihelion occurs during the N.H. winter (highly favorable for increase summer snow cover), obliquity is 23.44 degrees which is at least neutral for an increase summer N.H. snow cover, while eccentricity of the earth’s orbit is currently at 0.0167 which is still elliptical enough to favor reduced summertime solar insolation in the N.H. and thus promote more snow cover.
In addition the present geographical arrangements of the oceans versus continents is very favorable for glaciation.
MECHANISM FOUR
High latitude major volcanic eruptions correlate to prolonged solar minimum periods which translates to stratospheric warming due to an increase in SO2 particles while promoting more lower troposphere cooling.
One theory of many behind the solar/volcanic connection is that MUONS, a by product of galactic cosmic rays can affect the calderas of certain volcanoes by changing the chemical composition of the matter within the silica rich magma creating aerosols which increase pressure in the magma chamber and hence lead to an explosive eruption.
Muon densities increase more in higher latitudes at times of weak solar magnetic activity, which is why volcanic activity in the higher latitudes will be affected more by this process.
These four mechanisms make a strong case for a solar /climate connection in my opinion, and if the prolonged solar minimum meets the criteria I have mentioned going forward and the duration is long enough I expect global cooling to be quite substantial going forward.
THE CRITERIA
Solar Flux avg. sub 90
Solar Wind avg. sub 350 km/sec
AP index avg. sub 5.0
Cosmic ray counts north of 6500 counts per minute
Total Solar Irradiance off .015% or more
EUV light average 0-105 nm sub 100 units (or off 100% or more) and longer UV light emissions around 300 nm off by several percent.
IMF around 4.0 nt or lower.
The above solar parameter averages following several years of sub solar activity in general which commenced in year 2005..
IF , these average solar parameters are the rule going forward for the remainder of this decade expect global average temperatures to fall by -.5C, with the largest global temperature declines occurring over the high latitudes of N.H. land areas.
The decline in temperatures should begin to take place within six months after the ending of the maximum of solar cycle 24.
NOTE 1- What mainstream science is missing in my opinion is two fold, in that solar variability is greater than thought, and that the climate system of the earth is more sensitive to that solar variability.
NOTE 2- LATEST RESEARCH SUGGEST THE FOLLOWING:
A. Ozone concentrations in the lower and middle stratosphere are in phase with the solar cycle, while in anti phase with the solar cycle in the upper stratosphere.
B. Certain bands of UV light are more important to ozone production then others.
C. UV light bands are in phase with the solar cycle with much more variability, in contrast to visible light and near infrared (NIR) bands which are in anti phase with the solar cycle with much LESS variability.
William Astley says:
“It appears we are going to experience a Heinrich event…”
Should we nuke the ice jam in the Fram straight to keep the ice flowing out of the Arctic when that happens then?
Though looking rationally at past behaviour, the current temperature is far too high to get a sudden drop in Arctic temperature, more likely it will slowly drop for several thousand years, like from the Eemian: http://upload.wikimedia.org/wikipedia/commons/9/9d/Epica-vostok-grip-140kyr.png
@ur momisugly PolicyCritic. One possible thing you are missing is Political Correctness, or the need to not rock the boat for reasons of preserving funding. Leif is a solar scientist and it is perhaps best he should distance himself from temperature speculation and stick to pure solar science as he does.
However, for the rest of us we can speculate. Whatever the mechanism, the apparent historical correlation between reduced sunspots and colder times would seem to be unassailable. The co2 faithful should be giving up their religion somewhere between 2020 and 2030.
@ur momisugly Ulric. I don’t know anything about nukes. But I suspect it’ll take quite a lot of them and probably won’t solve the problem.
@ur momisugly Salvatore. A reduction in UV (ultra violet) light then should have a profound effect on the amount of energy entering the ocean surface waters
Got any numbers (joules or watts or something) for that energy ?
Lief, glad you showed the 24 cycle 14 comparison in your talk…….I had been looking at cycle comparisons and plotting them for some time and came to exactly that conclusion!
And like you said several times, cycle 14 is multi-peaked and so is cycle 24 likely to be multi-peaked.
Pamela Gray: I for one just can’t find a variable solar mechanism with that kind of watts per square meter muscle to drive a temperature trend measured at our planet’s surface.
My reading, hardly exhaustive, has led me to the same place: no convincing demonstration has been provided linking a hypothesized mechanism to the association of solar cycles with Earth temperature. The time series of solar measurements and the time series of Earth temperature could be completely independent time series, and of the zillions of time series data that humans have collected, it is happenstance that their peaks and troughs happen to line up, at least approximately.
But do we have enough evidence that there is no mechanism behind the association?
I expect the next 20 years to be extremely informative. If the Earth mean temperature continues to diverge from what is predicted of it, or to decline, while CO2 continues to increase and sunspot activity continues to decline, then I think the hypothesis of no causal link between sunspot activity and Earth temperature will lose credibility, and the hunt for evidence of mechanism will increase. Personally, I put this in the class of known unknowns.
Salvatore del Prete: NOTE 1- What mainstream science is missing in my opinion is two fold, in that solar variability is greater than thought, and that the climate system of the earth is more sensitive to that solar variability.
NOTE 2- LATEST RESEARCH SUGGEST THE FOLLOWING:
A. Ozone concentrations in the lower and middle stratosphere are in phase with the solar cycle, while in anti phase with the solar cycle in the upper stratosphere.
B. Certain bands of UV light are more important to ozone production then others.
C. UV light bands are in phase with the solar cycle with much more variability, in contrast to visible light and near infrared (NIR) bands which are in anti phase with the solar cycle with much LESS variability.
There is a great quantity of work to be done to cover the distance between that post of yours and a quantitative demonstration of the sort Pamela Gray referred to. I expect scientists to find a lot of illuminating evidence in the upcoming 20 years.
More solar inputs in changing “surface atmospheric pressure.”
What do with all the solar inputs.. oh my
The interplanetary magnetic field influences
mid-latitude surface atmospheric pressure
M M Lam, G Chisham and M P Freeman
British Antarctic Survey, High Cross, Madingley Road, Cambridge CB3 0ET, UK
Published 4 October 2013
http://iopscience.iop.org/1748-9326/8/4/045001/pdf/1748-9326_8_4_045001.pdf
Abstract
The existence of a meteorological response in the polar regions to fluctuations in the
interplanetary magnetic field (IMF) component By is well established. More controversially,
there is evidence to suggest that this Sun–weather coupling occurs via the global atmospheric
electric circuit. Consequently, it has been assumed that the effect is maximized at high
latitudes and is negligible at low and mid-latitudes, because the perturbation by the IMF is
concentrated in the polar regions. We demonstrate a previously unrecognized influence of the
IMF By on mid-latitude surface pressure. The difference between the mean surface pressures
during times of high positive and high negative IMF By possesses a statistically significant
mid-latitude wave structure similar to atmospheric Rossby waves. Our results show that a
mechanism that is known to produce atmospheric responses to the IMF in the polar regions is
also able to modulate pre-existing weather patterns at mid-latitudes. We suggest the
mechanism for this from conventional meteorology. The amplitude of the effect is comparable
to typical initial analysis uncertainties in ensemble numerical weather prediction. Thus, a
relatively localized small-amplitude solar influence on the upper atmosphere could have an
important effect, via the nonlinear evolution of atmospheric dynamics, on critical atmospheric
processes.
I am a big fan of Dr Svalgaard but I really don’t understand why he can’t at least suggest that the 100 year cycle might relate to changes in the solar motion of the large planets around the sun as in the case of the 11 year solar cycle.
c, that looks rife with mechanisms for amplification without runaway.
==========
In reply to:
Ulric Lyons says:
December 14, 2013 at 12:41 pm
William Astley says:
“It appears we are going to experience a Heinrich event…”
Should we nuke the ice jam in the Fram straight to keep the ice flowing out of the Arctic when that happens then? Though looking rationally at past behaviour, the current temperature is far too high to get a sudden drop in Arctic temperature, more likely it will slowly drop for several thousand years, like from the Eemian:
William,
It will be interesting to hear the suggestions to address planetary cooling. There is no respect for abrupt climate change as the group think does not include a mechanism to cause abrupt climate change. The warmists argue irrationally that the planet must amplify forcing changes in order for there to be an explanation as to how insolation changes at 65N could cause the glacial/interglacial cycle, as the insolation changes are an order of magnitude too small to cause what is observed in addition to there being multiple periods when there is a lack of correlation which disproves that mechanism. The lack of warming and Lindzen et Choi’s paper indicates the planet resists forcing changes by increasing or decreasing cloud in the tropical region. If it is a fact that the planet resists forcing changes, then there is a massive periodic forcing change which causes abrupt climate change and the interglacial/glacial cycle.
http://www.esd.ornl.gov/projects/qen/transit.html
The time span of the past few million years has been punctuated by many rapid climate transitions, most of them on time scales of centuries to decades or even less. The most detailed information is available for the Younger Dryas-to-Holocene stepwise change around 11,500 years ago, (William: 70% of the Younger Dryas cooling occurred in less than a decade) which seems to have occurred over a few decades. The speed of this change is probably representative of similar but less well-studied climate transitions during the last few hundred thousand years. These include sudden cold events (Heinrich events/stadials), warm events (Interstadials) and the beginning and ending of long warm phases, such as the Eemian interglacial. Detailed analysis of terrestrial and marine records of climate change will, however, be necessary before we can say confidently on what timescale these events occurred; they almost certainly did not take longer than a few centuries.
Various mechanisms, involving changes in ocean circulation, changes in atmospheric concentrations of greenhouse gases or haze particles, and changes in snow and ice cover, have been invoked to explain these sudden regional and global transitions. We do not know whether such changes could occur in the near future as a result of human effects on climate. Phenomena such as the Younger Dryas and Heinrich events might only occur in a ‘glacial’ world with much larger ice sheets and more extensive sea ice cover. However, a major sudden cold event did probably occur under global climate conditions similar to those of the present, during the Eemian interglacial, around 122,000 years ago. Less intensive, but significant rapid climate changes also occurred during the present (Holocene) interglacial, with cold and dry phases occurring on a 1500-year cycle, and with climate transitions on a decade-to-century timescale. In the past few centuries, smaller transitions (such as the ending of the Little Ice Age at about 1650 AD) probably occurred over only a few decades at most. All the evidence indicates that most long-term climate change occurs in sudden jumps rather than incremental changes.
According to the marine records, the Eemian interglacial ended with a rapid cooling event about 110,000 years ago (e.g., Imbrie et al., 1984; Martinson et al., 1987), which also shows up in ice cores and pollen records from across Eurasia. From a relatively high resolution core in the North Atlantic. Adkins et al. (1997) suggested that the final cooling event took less than 400 years, and it might have been much more rapid.
kim says:
December 14, 2013 at 4:42 pm
c, that looks rife with mechanisms for amplification without runaway.
==========
Two step process..
The interplanetary magnetic field influences
mid-latitude surface atmospheric pressure
M M Lam, G Chisham and M P Freeman
Published 4 October 2013
http://iopscience.iop.org/1748-9326/8/4/045001/pdf/1748-9326_8_4_045001.pdf
page 5
4. Discussion and conclusions
To explain the observed correlation of IMF By with surface
pressure we propose that the mid-latitude surface pressure is
influenced by IMF By via a two-stage process comprising:
(i) a change in the polar surface pressure involving the
global atmospheric electric circuit [5, 6], and
(ii) a resulting change in the mid-latitude surface pressure via conventional
meteorology.
The first of these two processes, concerning
the influence of IMF By fluctuations on the polar surface
pressure remains under-explored and controversial [17, 18].
However, our analysis of the surface pressure anomaly field
provides new evidence supporting a direct relationship
with the ionospheric electric potential.
Figure 3 is a schematic representing this two-stage
process:
Continued..
The interplanetary magnetic field influences
mid-latitude surface atmospheric pressure
M M Lam, G Chisham and M P Freeman
Published 4 October 2013
http://iopscience.iop.org/1748-9326/8/4/045001/pdf/1748-9326_8_4_045001.pdf
..In particular, it affects the structure of the Rossby
wavefield, which is key in determining the trajectory of
storm tracks [24]. The configuration of the North Atlantic jet
stream is particularly susceptible to changes in forcing [25].
In turn, so are the location and the timing of blocking
events in this region, in which vortices are shed from the
jet stream leading to prolonged periods of low or of high
pressure [26]. It has also been proposed that the low-frequency
variability of the North Atlantic Oscillation (NAO) arises as a
result of variations in the occurrence of upper-level Rossby
wavebreaking events over the North Atlantic [27]. The NAO
itself is key to climate variability over the Atlantic–European
sector stretching from the east coast of the United States to
Siberia, and the Arctic to the subtropical Atlantic [28, 25].
Our results may therefore provide part of the explanation
for previously observed correlations between Eurasian winter
temperatures and solar variability [29, 30], and for the ‘Wilcox
effect’ where reductions in the areas of high vorticity in
winter storms are seen at times of solar wind heliospheric
current sheet crossings [31] (which are characterized by sharp
changes between steady, opposite IMF By states).
Thanks Dr Svalgaard and Anthony – this has been an extremely interesting post.
:o)
I have been reading this article and the comments with great interest. I have come to a conclusion (interpretation) about the suns influence on our weather and climate, as have many writers in a certain genre. We on Earth actually live in a Petry dish, the changes in the weather are caused by a [rest not in accordance with site policy. Mod]
Matthew R Marler says:
December 14, 2013 at 2:53 pm
The time series of solar measurements and the time series of Earth temperature could be completely independent time series, and of the zillions of time series data that humans have collected, it is happenstance that their peaks and troughs happen to line up, at least approximately.
Possible, but unlikely to this extent:
http://www.vukcevic.talktalk.net/GSC1.htm
As it can be seen, more accurate data (closer to present time) closer is the correlation.
John F. Hultquist says:
December 14, 2013 at 8:53 am Thanks
Ric Werme says:
December 14, 2013 at 10:03 am Thanks