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(Thanks TO ‘OLDBREW’)
for finding this information . If there is a connection with Earths climate it warrants a post of its own.
As get more info’ I will do a few time series correlations

Heliospheric current sheet
solar wind

Sleepy sun thickens the slow solar wind

17:14 10 January 2014 by Stuart Clark

Even the sun needs a break. A slowdown in solar activity has given us the first real clue about a period of dramatic solar behaviour 350 years ago.

In 2008, the sun entered a deep lull in magnetic activity. Spacecraft measurements show that this caused a belt of sluggish particles, known as the slow solar wind, to thicken. Produced near the sun’s equator, the belt is normally narrow and ruched like a ballerina’s tutu. The particles there flow at about 336 kilometres a second, as opposed to 550 kilometres a second in the fast solar wind produced closer to the sun’s poles.

Because Earth orbits at a 14 degree tilt relative to the sun’s equator, it passes in and out of these ruches during the year. As solar activity dwindles, the belt thickens, and we spend more time passing through it. The speed of the slow solar wind affects the temperature of Earth’s upper atmosphere, and impacts climate.

To find out how severe such slowdowns might be, Mike Lockwood and Matt Owens at the University of Reading, UK, used the 2008 measurements to model the belt’s thickness during the most extreme solar minimum on record: the Maunder Minimum. This lasted from 1645 to 1715 and corresponded to a minor ice age.

Not so windy

The model showed that the solar wind speed probably dropped to just 250 to 275 kilometres a second during this period. Earth spent six months of the 2008 minimum in the slow solar wind, but it probably spent all 70 years of the Maunder Minimum there.

Lockwood says the current weak cycle could herald the sun dipping into another extended period of inactivity. The temperature of Earth’s upper atmosphere affects the speed at which satellite orbits decay, so a prolonged drop in the solar wind speed would cool and shrink the atmosphere and diminish the drag on satellites. This would exacerbate the space junkMovie Camera problem because debris would be slower to re-enter Earth’s atmosphere, where it burns up harmlessly.

But don’t expect another mini ice age, says Lockwood. The Maunder Minimum was also characterised by an almost total lack of sunspots, which record how the solar dynamo, which creates the sun’s magnetic field, is churning. We still do not understand that well enough to predict when another Maunder Minimum might occur.

“Until we know why the sun occasionally drops into these grand minima, we won’t really understand the solar dynamo,” says Lockwood.

Journal reference: Astrophysical Journal Letters, DOI: 10.1088/2041-8205/781/1/L7

Implications of the Recent Low Solar Minimum for the Solar Wind during the Maunder Minimum

M. Lockwood and M. J. Owens
Show affiliations

M. Lockwood and M. J. Owens 2014 ApJ 781 L7. doi:10.1088/2041-8205/781/1/L7
Received 18 November 2013, accepted for publication 5 December 2013. Published 23 December 2013.
? 2014. The American Astronomical Society. All rights reserved.

The behavior of the Sun and near-Earth space during grand solar minima is not understood; however, the recent long and low minimum of the decadal-scale solar cycle gives some important clues, with implications for understanding the solar dynamo and predicting space weather conditions. The speed of the near-Earth solar wind and the strength of the interplanetary magnetic field (IMF) embedded within it can be reliably reconstructed for before the advent of spacecraft monitoring using observations of geomagnetic activity that extend back to the mid-19th century.

We show that during the solar cycle minima around 1879 and 1901 the average solar wind speed was exceptionally low, implying the Earth remained within the streamer belt of slow solar wind flow for extended periods. This is consistent with a broader streamer belt, which was also a feature of the recent low minimum (2009), and yields a prediction that the low near-Earth IMF during the Maunder minimum (1640-1700), as derived from models and deduced from cosmogenic isotopes, was accompanied by a persistent and relatively constant solar wind of speed roughly half the average for the modern era.


2 comments on “SOLAR WIND and EARTHS CLIMATE

  1. Graph by VUKCEVIC
    VUKCEVIC says

    “Two magnetic polarities are separated by the heliospheric current sheet (HCS), thus the Earth sees only one at any time.
    How much time the earth spends in each polarity is determined by the tilt angle of the HCS, which is considerably different between even and odd cycles.




    All Earth’s electrically conducting (from wires to ocean currents) and electrically charged (from clouds to ionosphere) systems differentiate between two solar magnetic polarities.
    For example when the Earth is swept by the HCS all geomagnetic stations record sharp magnetic spike of one or the other polarity depending on the direction of the crossing.

    As a consequence,

    the 22 year cycle is present in both land and ocean temperatures.

    Here is the NOAA’s land and ocean temperature anomaly and its spec, with the 22 year component the most prominent one.

    hale cycle VS global temp

    How does it work? That is much harder to answer; for a test we cannot turn it off, but according to (my) extrapolation there is a remote possibility that the sun just may do us a favour and switch it off for ~ 10-11 years (starting about 2020)

    Discussed here

  2. ANIMATION of current Heliospheric current sheet

    ( thanks to Vukcevic for the link)
    Vukcevic continues
    “The Earth is always under the influence of the interplanetary magnetic field. When the leading edge is magnetized north it connects into the earth’s magnetosphere.
    Heliospheric current sheet is very narrow, transition is a matter of minutes or mostly hour or two. With CMEs the same principle applies, but effect may last day or two, even longer, CMEs are far stronger and faster than solar wind and push it out of the way.
    Magnetic polarities + & – (read/blue periphery lines), HCS (white line) and a CME (multi-coloured moving magnetic cloud) are best observed from the middle animation in this link .
    NASA’s statistical analysis shows that in the even solar cycles the sun’s originated MF’s north polarity leading edge is prevailing, while opposite is the case in the odd cycles.”

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