Solar Wind at a 50 year low

[TimBikes]

NASA held a press conference today to discuss the recent strange behavior of the sun. Since we have seen global temperatures stabilize and even drop since the 1990's, it seems quite possible that the sun is a causal factor. Certainly Svensmark has proposed such a connection via cosmic ray flux, though that connection is still being explored.

It is also worth noting that sunspot activity appears unusually low and the start of a new solar cycle has been delayed. Strange.

"The average pressure of the solar wind has dropped more than 20% since the mid-1990s," says Dave McComas of the Southwest Research Institute in San Antonio, Texas. "This is the weakest it's been since we began monitoring solar wind almost 50 years ago."

"What we're seeing is a long term trend, a steady decrease in pressure that began sometime in the mid-1990s," explains Arik Posner, NASA's Ulysses Program Scientist in Washington DC.

In addition to weakened solar wind, "Ulysses also finds that the sun's underlying magnetic field has weakened by more than 30% since the mid-1990s," says Posner. "This reduces natural shielding even more."
Unpublished Ulysses cosmic ray data show that, indeed, high energy (GeV) electrons, a minor but telltale component of cosmic rays around Earth, have jumped in number by about 20%.



Also, there are controversial studies linking cosmic ray fluxes to cloudiness and climate change on Earth. That link may be tested in the years ahead.

[KMO]

I read that piracy is on the up. Given the long-established inverse correlation between pirates and global temperature, I think that already have a good hypothesis to explain any cooling, were it actually to occur.

[KD6HDX]

Being a ham radio operator, I keep an eye on solar activity. Radio operators worldwide are anxiously awaiting solar cycle 24, an eleven year cycle of increased ionization of specific layers of our atmosphere that increases DX, or worldwide radio comms. I have read recent news about a MAUNDER minimum, or SPORER or DALTON minimum. I find it very interesting that theories about global COOLING are increasing. Lets hope that the cycle kicks up and promotes DX conditions for hams worldwide, without harming or heating our environment. Here is a link from a ham radio page that speaks of a new sunspot or two that are bigger than the size of our earth.

http://forums.qrz.com/showthread.php?t=176761

Some folks believe that a decrease in solar activity or sunspots, may actually cause the mini ice age that a MAUNDER minimum predicts. So the burning of hydrocarbons as fuel may actually keep the temps somewhat habitable instead of uninhabitable. Just a working theory anyway. What say anyone?

73 to all (best regards in radio jargon)
KD6HDX

[Betelgeuse]

Yeah. The Sun is acting bizarre these days. August was the first month in almost 100 years with ZERO sunspots and, while we're at solar minimum, the solar activity is quite low for a minimum.

There's little doubt that solar activity affects climate. The concern would be if we're artificially holding the temperature up via pollution. Then, when the Sun returns to a normal activity level, the global temperature may be boosted even more. Who knows? The Sun may come to our rescue; if we have an extended period of low solar activity, it may keep temperatures down long enough for us to get our sh!t together and bring down pollution levels. This is all pure speculation; the solar activity has only been abnormally low for ~a year. We'll have to see what the next year brings.

[jayman]

I just hope this isn't leading up to a period of catastrophically high solar activity, like a repeat of the 1859 Carrington's Flare. The GIC was so intense, telegraph operators had to avoid their equipment due to sparks flying off the wires.

Our modern infrastructure is fairly vulnerable to a super flare, especially intense GIC. Pipeline operators in Scandinavian countries note currents upwards of 60 amps in the pipelines when sunspots are peaking

[richard schumacher]

If reduced Solar activity leads to lower temperatures then we can expect a hellish rebound in global warming when the Sun returns to normal, given the tens of billions of tonnes of excess CO2 we've been pumping into the air. If this is a reprieve we need to make the most of it, not go on with business as usual.

[TimBikes]

Originally Posted by richard schumacher

If reduced Solar activity leads to lower temperatures then we can expect a hellish rebound in global warming when the Sun returns to normal, given the tens of billions of tonnes of excess CO2 we've been pumping into the air. If this is a reprieve we need to make the most of it, not go on with business as usual.

Solar activity in the latter 1/2 of the 20th C was not "normal" - the sun was overly active.

So if the sun returns to a "normal" state, I think we have little to fear.

[chogan2]

Well, my take on this is that trying to explain recent warming as the result of change in solar flux is just grasping at straws.

First, there's the general comment that any alternative explanation of the warming is not complete unless it also proposes why GHGs buildup doesn't warm the earth. As far as I know there is no serious disagreement that GHGs should warm the earth. The theoretical size of the climate forcing from GHGs is enough to explain the recent warming. And, as realclimate.org expresses it, if you take the GHG buildup out of climate models, no other known factor is large enough to explain the temperature rise. So my first comment to any proposed alternative explanation is, well, finish the proposed explanation by explaining why GHGs don't matter.

Second, the direct effect of the change in solar irrradiance is far too small to explain the warming. Yes, slightly more solar energy reaches the earth now than in (say) 1750, but as far as I read, the estimate of the change is quite small. Certainly, in the modern era (say 1950 on), the directly measured change is small. From solar peak to solar trough, the change in forcing is equivalent to about 5 years of GHG buildup at current levels, based on what I've read on realclimate.org. It is a non-negligible component, and it is included in the climate models, but it's not large enough to explain the temperature rise.

Third, so that means any solar-based theory has to rely on more esoteric processes, such as the link between cosmic ray flux and cloud formation. Yeah, that might happen. But at this point it's just a hypothesis -- cosmix rays will generate tiny condensation nuclei, but I don't think it has been shown that those nuclei are large enough to form clouds. And more to the point, there hasn't been any trend in cosmic ray flux over the last half a decade. This is described in detail here:

RealClimate

So, at the end of the day, I judge it improbable that changes in solar activity are the driver of recent temperature changes. The direct change in solar irradiance has been too small to do it. The main candidate among the more esoteric mechanisms -- cosmic ray flux changing cloud formation rates -- relies on a yet-to-be-proven mechanism by which the condensation nuclei formed by cosmic rays grow large enough to become cloud condensation nuclei. This argument also ignores the lack of trend in cosmic ray flux over the past half-century. Finally, people who propose the sun as the source of the warming need to further explain why all of the theoretical calculations of the impact of GHGs on warming are incorrect.

[markderail]

Dr Phil Plait's blog explains it well, without inducing headaches.

An ill solar wind blows no good | Bad Astronomy | Discover Magazine

[Betelgeuse]

Originally Posted by markderail

Dr Phil Plait's blog explains it well, without inducing headaches.

An ill solar wind blows no good | Bad Astronomy | Discover Magazine

+1

Phil Plait is one of the better "science communicators" of our time. He does a great job explaining what we know at a pretty high level but, at the same time, makes it accessible for non-experts. It's entertaining to see his pseudo-rockstar status at Astronomy meetings.