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Sun's Activity Levels Reconstructed
neutron_p writes "An international team of scientists has reconstructed the Sun's activity over the last 11 millennia and forecasts decreased activity within a few decades. The activity of the Sun over the last 11,400 years, i.e., back to the end of the last ice age on Earth, has now for the first time been reconstructed quantitatively. The scientists have analyzed the radioactive isotopes in trees that lived thousands of years ago. As scientists report in the current issue of the science journal Nature, one needs to go back over 8,000 years in order to find a time when the Sun was, on average, as active as in the last 60 years."
this isn't, co-incidentally, the same amount of time we've been traking a growing hole in the ozone layer over Antarctica, is it?
Only two things are infinite, the universe and human stupidity, and I'm not sure about the former. (Einstein)
In order to investigate the issue, NASA has announced that they are sending an unmanned space probe to the sun. In order to avoid the intense heat, they are planning on launching the probe at night.
Unknown host pong.
I'm not sure I trust their error bars (they appear on the second plot). Since they're using 10-year averages, they should be removing the effects of the solar cycle. But their sunspot number curves drop below 0 sunspots in several places. A negative number of sunspots is, obviously, unphysical. Also, their data is pretty wildly varying over short timescales (again, solar cycle should be removed) and doesn't match the actual sunspot records from 1610 on very well, either.
n/t
They've been around for so long and their Java-Interpreter is still not... Oh, wait, you mean that other sun, don't you?
One thing I'm curious about is what effect that the Sun's activity has on climate change. There have been spacecraft studying the sun and more spacecraft studying the magnetosphere and it's interaction with the solar wind. However, it seems that we only have understanding of individual events and the immediate effects of those events. It will be really interesting when some people get a good idea of what long term effects CMEs (coronal mass ejections) and other Sun activity has on our little blue world.
I wonder if instead of just examining the historical record, they also took one additional factor into account.
Physicists modelling the history of the Sun say that its overall brightness (read: activity level) has increased by about 30% since being born. This is related to the buildup of helium "ash" (from fusion of hydrogen) in its core. Furthermore, the trend is expected to continue -- quite slowly, of course. Nevertheless, any forcast that the current activity can be expected to decrease in the next few years -- or even decades -- might be rather "off" if that factor is not taken into account....
So... we'll schedule the Global Cooling panic for what, 2030-ish? That good for everyone?
Save your Global Cooling books from the 70s, they'll be invaluable in showing how long it has been a problem even as the Global Warming hysteria is quietly, but thoroughly, whitewashed out of existance (just as the Global Cooling panic has been, as of today).
See you then!
(This is about 1/3 humorous, 1/3 a troll, and 1/3 an attempt to get people to be a little less dogmatic and a little more thoughful about climate issues in general. Moderate accordingly, I guess.)
(PS: I would expect the Earth's temp, if it is affected significantly by the Sun, to lag behind it by several years, because it has one hell of a lot of "thermal inertia".)
I just hope we have enough hydrocarbons to survive the oncoming dark. This explains where all the light is going though: Previously reported here
...But I digress. TREMBLE PUNY HUMANS!ONE DAY MY SPECIES WILL DESTROY YOU ALL!
The temperature variations have been tracked over centuries using heat-flow measurements in boreholes.
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I think this is a very significant find. The sun is the single most dominant factor in environmental conditions.
While we know that there are ways to deflect or absorb sunlight in the earth, this only deals with a fraction of the sun's energy. For instance, putting more water in the atmosphere will "reflect" the sun's light, but even if we saturated the atmosphere with water to reflect excess incoming sunlight, we wouldn't be able to do enough should the sun increase its radiation. Conversely, if we used greenhouse gasse to trap the sun's heat, if the sun drops in output, there will be less to trap, and the "warmest" blanket of greenhouse gasses will not be enough to keep the earth warm.
What does this mean? It means that the weather is something beyond our control and our understanding. Until we can control the output of the sun, we can't expect to control the weather on earth.
The radical sect of Islam would either see you dead or "reverted" to Islam.
The Sun is approximately 4.5 billion years old. An increase in the average brightness of 30% over that time is equal to 6.7% per billion years, or .00000067% per century. If you think that this will become a measurable change in the next century, you obviously never learned anything worthwhile from a lab course (and nobody should trust you with numerical methods, either).
Sustainability and energy independence essay
Except, if you had read the article, you'd see that it quite explicitly says that this study shows that solar activity does not account for the rise is global average temperature since the start of industrial revolution.
Sustainability and energy independence essay
Here's another article that talks a little more about the findings, including a very short discussion on possible implications regarding climate change and global warming. Although a correlation makes sense and there appears to be a link between global climate change and sunspots in several instances, there is not enough data to be conclusive and the current warming trends do coincide with increasing levels of methane and CO2. It could be either or both.
In addition to the obvious question of whether this affects our climate, the findings are interesting simply because they provide more information about our sun. I think it's amazing we can look at carbon-14 content here on earth an make inferences about the solar weather 10000 years ago. They're using this to show indirectly that the sun exhibits it's own long term "climate changes" as expected. Of course, other bodies do this as well. For example, that hurricane on Jupiter (the red spot) that's been hanging around for just a little bit longer than Frances.
I believe the now-cancelled Solar Probe mission was to have flown at night, for the same reason you posted. IIRC, some portion of its trajectory was to have placed it in the shadow of a sun-grazing asteroid...local night. This would have a) kept its electronics cool until it was ready to begin its final mission, and b) given us a chance to study the asteroid at close range.
Since the mission was cancelled, the NASA "Fire and Ice" page (combining this mission and the Pluto-Kupier Belt probe has been taken down), so I can't verify that this was the plan.
Time is Nature's way of keeping everything from happening at once... the bitch.
OMFG guys! It's solar warming! Kill the Republicans!
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