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Space Science

Sunspots Return 276

We're emerging from the longest, deepest sunspot drought since 1913 (we discussed its depths here) with the appearance of a robust group of sunspots over the weekend. Recently we discussed a possible explanation for the prolonged minimum. The Fox News article quotes observer Michael Buxton of Ocean Beach, Calif.: "This is the best sunspot I've seen in two years." jamie found a NASA site where you can generate a movie of the recent sunspot's movement — try selecting the first image type and bumping the resolution to 1024. The magnetic field lines are clearly visible.
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Sunspots Return

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  • by Anonymous Coward on Tuesday July 07, 2009 @03:48PM (#28612845)

    Not visible != imaginary. Magnetic lines very much exist, as any kid who has played with a magnet and iron filings can tell you.

    Amusingly, my captcha is arrogant

  • Is it just me ? (Score:3, Interesting)

    by ls671 ( 1122017 ) * on Tuesday July 07, 2009 @03:49PM (#28612861) Homepage

    Is it just me and where I live or have last summer and winter been pretty warm while this current summer seems cooler with the return of the sun's spot ? ;-)))

  • by Jane Q. Public ( 1010737 ) on Tuesday July 07, 2009 @03:52PM (#28612895)
    I saw the tag but haven't seen this explicitly mentioned yet: one theory is that lack of sunspots causes Earth to warm up. (There is a very strong negative correlation between sunspot activity and temperature on Earth.)

    Maybe now we'll find out who's right.
  • by gr8_phk ( 621180 ) on Tuesday July 07, 2009 @04:03PM (#28613021)
    Yeah, because the field is not uniform the iron filings clump around the actual physical lines. It's the same thing with gravity - the field is not uniform, but concentrated along specific lines protruding out of the earth. Sometimes you get tripped up when you walk through one of the bigger gravitational field lines. Here in Michigan you can clearly feel them when driving your car through them - it feels like the road is all bumpy.

    *end sarcasm*

    The comment that they are imaginary does suggest that the plasma (or something) on the sun somehow concentrates the field much the way iron filings concentrate them. Once you have filings it concentrates the field and you get more filings attached to the end thus creating lines. Similar must occur on the sun or the lines would not be visible.
  • Re:CQ DX (Score:4, Interesting)

    by AB3A ( 192265 ) on Tuesday July 07, 2009 @04:15PM (#28613203) Homepage Journal

    DX from the other side of the earth on 10 meters at 1 AM? I remember those days. Now if only we could find a way to get the LIDS to learn how to troll the Internet, why we might actually have a civilized conversation on the air!

  • Man saved Earth? (Score:5, Interesting)

    by Spy Handler ( 822350 ) on Tuesday July 07, 2009 @04:20PM (#28613261) Homepage Journal
    IIRC, the last time sunspots were at a minimum like this, earth was in the little ice age, and hundreds of millions of people died due to crops freezing, glaciers overrunning towns, disease, etc.

    So maybe we're supposed to be in another little ice age, but all the greenhouse gases warmed the planet and saved us?

  • by NotNormallyNormal ( 1311339 ) on Tuesday July 07, 2009 @04:43PM (#28613633)
    As a space physicist, I agree. Certainly we have seen an increase in the number of sunspots in the last month but most die out rapidly. However, other solar activity, such as corona holes (of which there are two) are becoming more common. The current set of holes [spaceweather.com] should cause activity at the Earth on or about the 12th of July.
  • by radtea ( 464814 ) on Tuesday July 07, 2009 @04:51PM (#28613755)

    There are some interesting data available on Earth's albedo (reflectivity): http://earth.myfastforum.org/sutra1069.php [myfastforum.org] Check out the linked sources, in particular.

    Summary: there is some evidence that Earth's albedo has decreased by as much as 2% (absolute, almost 10% relative) in the past twenty years. A decrease in albedo means less visible light is being reflected by the planet, implying that more is being absorbed, which would tend to increase planetary heat content.)

    A 2.0% variation in albedo is huge: over twice the effect of all anthropogenic greenhouse gases combined (6.8 W/m**2 vs about 5 W/m**2). However, because much of the change is due to changes in cloud cover, one must also account for the changes in infrared absorption from different kinds of clouds, which makes a head-to-head comparison tricky. However, while the effect of different types of cloud cover can reduce the effect of albedo variations, the residual is still as large or larger than current estimates of human greenhouse gas contributions to climate forcing.

    Final grain of salt: albedo is a physically meaningful term, unlike "global average temperature", but it is still very tricky to measure, and therefore these results should be taken with a grain of salt. However, the magnitude of the effect is such that it is difficult--but not impossible--to imagine it not having a pretty major influence on climate.

    Cloud cover maybe correlated with cosmic ray flux, which may be correlated with sunspot activity.

    Based on the data we have, it appears Earth's albedo has been anomalously low in the past decade or more, and may now be popping back up to something closer to the long term average (0.315 as opposed to as low as 0.305 in the past decade). If that is the case, then we can expect to see a pronounced drop in "global average temperature" in the next few years.

    If that happens, then climate forcing due to albedo variation is going to start looking pretty plausible as a significant cause of the high "global average temperatures" seen in the past decade.

  • Re:Oh sure... (Score:4, Interesting)

    by Geoffrey.landis ( 926948 ) on Tuesday July 07, 2009 @04:52PM (#28613777) Homepage

    Anyone who offers valid criticisms of your theory with data to back them up should be heard.

    Tell that to Pons and Fleischmann.

    They might get a Nobel yet.

    Probably not.

    If cold fusion turns out to be, as it looks, a combination of erroneous measurements and wishful thinking, then they will be ignored and eventually forgotten.

    On the other hand, if cold fusion turns out to have been a real effect after all, then somebody should hunt them down and shoot them, because by their actions, they made it look like bad measurements, chicanery, and hype, and thus made sure nobody would take it seriously. If there really was something there, their actions set science back significantly.

  • by Anonymous Coward on Tuesday July 07, 2009 @05:00PM (#28613897)

    No it hasn't. In fact we are pretty much at the same level we were in 1850 for sunspots.

  • Re:Is it just me ? (Score:3, Interesting)

    by JobyOne ( 1578377 ) on Tuesday July 07, 2009 @05:01PM (#28613901) Homepage Journal
    It's you and where you live. Where I live (Albuquerque, New Mexico, USA) we had an unusually warm and dry winter, and are currently in the middle of a slightly hot and unusually humid summer.

    I don't like it one bit. Our moisture is supposed to come from melting snow in the mountains...not torrential downpours ruining cars, roofs and vegetation with hail and flooding roads because the ground is too dry and hard to absorb all that at once.
  • Re:Is it just me ? (Score:3, Interesting)

    by CorporateSuit ( 1319461 ) on Tuesday July 07, 2009 @05:54PM (#28614699)

    Because local climate suddenly equates to global mean temperature? Huh... go figure...

    Um... Because solar weather affects global weather.

  • Re:Is it just me ? (Score:3, Interesting)

    by DerekLyons ( 302214 ) <fairwater.gmail@com> on Tuesday July 07, 2009 @06:31PM (#28615177) Homepage

    It's just you - here in the Pacific Northwet, it's been exactly the opposite.

  • by BlueParrot ( 965239 ) on Tuesday July 07, 2009 @06:54PM (#28615367)

    Since there will of course be a lot of nonsense about this having implications for the reliability of the IPCC's statements on climate change and so on, it is worth posting the following:

    We have direct measurements of incoming and outgoing solar radiation. We have satellites in orbit that detect incoming as well as outgoing radiation of all wavelengths. From these direct measurements we know that the recent change in outgoing radiation is greater than the changes in incoming radiation. We know that the change is in the region of the spectrum where CO2 and other greenhouse gasses absorb radiation the most. We also know from isotopic analysis that a majority of the increase in CO2 concentration is fossil in origin ( fossil fuels are virtually depleted in Carbon 14 since it decays radioactively over periods of several thousand years ), thus excluding the possibility that what we see is a feedback effect from changes in solar activity.

    Thus we more or less know that the sun is not to blame, no matter how poorly we may understand its sunspots, cycles and whatnot. The change in radiation balance is due to neither a direct solar effect nor the type of feedbacks that occur during ice age termination. If either of the two was the case then the isotopic studies would have detected it since the CO2 in oceans and plants have comparable C14 concentrations as the atmosphere. Instead what we see is an increased concentration of fossil carbon in the atmosphere, and together with it a reduction in outgoing infra-red radiation consistent with the absorption spectra of the greenhouse gases we emit.

...there can be no public or private virtue unless the foundation of action is the practice of truth. - George Jacob Holyoake