Slashdot is powered by your submissions, so send in your scoop


Forgot your password?
NASA Space Science

Big Drop In Solar Activity Could Cool Earth 569

coondoggie writes "Scientists say the Sun, which roils with flares and electromagnetic energy every 11 years or so, could go into virtual hibernation after the current cycle of high activity, reducing temperatures on Earth. As the current sunspot cycle, Cycle 24, begins to ramp up toward maximum, scientists from the National Solar Observatory and the Air Force Research Laboratory independently found that the Sun's interior, visible surface, and corona indicate the next 11-year solar sunspot cycle, Cycle 25, will be greatly reduced or may not happen at all."
This discussion has been archived. No new comments can be posted.

Big Drop In Solar Activity Could Cool Earth

Comments Filter:
  • Re:Oh good... (Score:4, Interesting)

    by MozeeToby ( 1163751 ) on Tuesday June 14, 2011 @05:52PM (#36442602)

    This has the potential to make Global Warming so much worse. Lets assume global warming is real and we're headed for a maunder minimum level of hibernation. The expected temperature increases are pretty similar to the temperature drops associated with the last major minimum. It would convince people that global warming was all a big sham or even a blessing, and in the short term the blessing idea wouldn't even be totally incorrect, since the effects of a half century long solar minimum would almost certainly be at least as devastating to civilization as global warming.

    But, that means that in 50-70 years, when the little ice age ends, we could be faced with the full force of global warming in less than a decade, instead of spread out over the course of half a century. It would be even more so to late to do anything about it, short of geoengineering at a massive scale, and even I, techno-optimist that I am, have difficulty accepting the idea that we'll be able to accurately manipulate the kinds of energy needed to alter the Earth's climate in a controlled way.

  • by sanzibar ( 2043920 ) on Tuesday June 14, 2011 @06:18PM (#36443066)

    Swedish mathematician Claes Johnson explains where the basic problem of radiation lies in the greenhouse effect:
    The basic postulate of IPCC climate alarmism is the relation dQ = 4 dT connecting radiative forcing dQ to global warming dT, with dQ = 4 Watts/m^2 from doubling of CO2 giving a climate sensitivity or global warming of dT = 1 C, which is inflated to 1.5 â" 4.5 C by feed back.

    The relation dQ = 4 dT comes from Stefan-Boltzmanns Radiation Law, which cannot be disputed as such.

    The reason the Radiation Law does not determine the temperature of the surface of the Earth to its value of 15 C, is that the Earth is one part of the coupled Earth-atmosphere system with radiation exchange between the parts. The Radiation Law determines the temperature of the surface of the system, the stratopause, to 0Â C, but not the Earth surface temperature.

  • by jamesl ( 106902 ) on Tuesday June 14, 2011 @06:22PM (#36443148)

    You're making this too complicated.

    The simple equation is Energy In (from the Sun) minus Energy Out (radiated at the top of the atmosphere) equals the change in Earth's energy content for which air temp is a proxy. If Energy In (from the Sun) is reduced and Energy Out remains unchanged, there is a net loss of energy from the earth and the temp goes down. Or at the very least, goes up more slowly.

  • by icebike ( 68054 ) on Tuesday June 14, 2011 @07:07PM (#36443718)

    Says more about the meteorologist than nature....

  • by rgbatduke ( 1231380 ) <rgb@ph y . d u k> on Tuesday June 14, 2011 @07:55PM (#36444186) Homepage

    COULD there be another cause?

    You mean, aside from the fact that the last forty or fifty years we were in a grand maximum of solar activity, the highest seen on earth since the very beginning of the Holocene? And that, given the unknowns and the egregious speculation that has occurred in lieu of actual research concerning the feedback, this is a confounding factor that has been more or less completely ignored by the AGW zealots? Do you mean to ignore (as those zealots wish to) the Maunder minimum and Dalton minimum, the "Year without a summer" in the Dalton minimum, and the other, substantial evidence that global climate is first and foremost driven by solar activity and at most modulated by everything else?

    To put it more seriously, think about putting error bars on the parameter that controls the feedback. Be sure to make them as large as the current estimates of the parameter itself, as we have no measurements to support one value over any other, only oversimplified model computations that ignore enormous amounts of the complex dynamics of the climate that are in indifferent agreement with the past and incapable (so far) of predicting the future. If we don't even know the correct sign of that parameter, let alone its magnitude, it is really easy to build a model that explains global warming over the last 160 years -- variations in solar activity that almost precisely parallel the observed increases in temperature, right up to the grand maximum (in both solar activity and global temperature) in the last few cycles of the twentieth century. Don't forget to allow for the 10-20 year lag in solar forcing and response in terms of global temperature change (clearly evident in the data and completely understandable given the vast heat capacity of the ocean and the complex feedback loops associated with the major oscillations in circulation).

    As for the "every chemistry or physics student knows" -- well, I teach physics including electrodynamics, and to me it is by no means clear that we have a particularly good idea of the full dynamics of heat trapping by CO_2 in the upper atmosphere, including all feedback loops and the climate sensitivity. It is hard to even build an accurate model, given that the trapping is such a small effect that NASA's satellites cannot directly measure it (and the concentrations we are talking about are very small indeed).

    The fundamental problem is that impending doom sells. It sells everything. It sells careers. It sells grants. It sells congress on providing money for those grants. It sells a completely artificial market with numerous opportunities for con men to get rich involving things like "carbon futures" or "carbon credits" (look carefully at just where Al Gore and his cohorts are invested, and I mean financially invested, if you want to see what I mean). It sells newspapers. It sells scientific journals. It sells novels and television shows. Even complete crackpot whacko doom such as Harold Camping's incredible shrinking Rapture sells -- sells to the tune of a hundred million dollars. The end of the world in 2012 sells. The earth being hit by entirely speculative and improbable coronal mass ejections in 2013 -- specifically, in 2013, not 2012 or 2014 -- sells. Asteroids hitting the earth sells. Back in the day, nuclear war and MAD sold. A glance at Hollywood's list of disaster movies, TV ditto, novels ditto, and sure, speculative science publications galore ditto, is enough to prove rather conclusively that impending doom sells!

    Science -- and I mean good science, the kind that is cautious and pessimistic and that hesitates to state unproven speculations as if they are definite proven facts -- does not sell, alas. Not in our bored and jaded culture. Do a study of earthworm mating habits that concludes with the observation that earthworms globally are doing rather well and that their critical contributions to our ecology are proceeding in an entirely natural and appropriate w

  • by Nemyst ( 1383049 ) on Tuesday June 14, 2011 @08:03PM (#36444250) Homepage

    Nature changes, but does not disappear. It can change extremely quickly, for better or for worse. If that isn't fickle, I don't know what it is.

    Note that fickle does not exclude robust, so your point's rather off-topic.

Someday your prints will come. -- Kodak