Sun Not a Significant Driver of Climate Change 552
damn_registrars writes "Scientists from Edinburgh, Scotland have recently published a study based on 1,000 years of climate data. They have compared the effects of differing factors including volcanic activity, solar activity, and greenhouse gases to find which has the most profound effect on climate. They have concluded that the driving factor since 1900 has been greenhouse gases."
no! no it hasn't! (Score:1, Informative)
weather stations near heat vents!
climatologists trying to make a buck off the rest of us!
anti free market hippies!
last time you said it was an ice age!
look at my linear fit to the last 4 years of data!
Re:In related news (Score:4, Informative)
Fortunately our sun can't go supernova, its too small, and has no close companion star to give it the extra mass needed.
However it is still a significant factor, after all if it wasn't there, this ball of rock would soon be covered in ice.
Re:Without the sun there is no climate change at a (Score:5, Informative)
I see you did not actually look at the Nature paper they published. The title is: "Small influence of solar variability on climate over the past millennium". The key word is variability. As in variations in solar activity aren't a major driver in climate change, not the Sun itself.
In other words, you are the loon.
110,000 year major glaciation Sun cycle (Score:3, Informative)
The article's title is patently false and provable as such. Time to report reality.
The Earth's orbital changes around the Sun varies from more circular to more elliptical and its axis wobble changes and the net effect is that the different solar inputs are what causes the major climate shift on about a 110,000 year cycle.
The Sun rules. Eventually as the Sun becomes a Red Giant, the Earth will become hotter until all life and water evaporates and eventually the Sun will effectively consume the Earth.
In a very short period of time, other factors may cause climate changes including asteroids, volcanism, forest fires and mankind's creation of soot, CO2 and such.
Re:And what was the driving factor before 1900? (Score:5, Informative)
How did the world warm up and cool down before then? Perhaps that is relevant?
Over geologic times, lots of things have affected Earth's climate. On astronomical time scales the Sun has an impact: as it ages the Sun emits more radiation: it becomes warmer. But not on human timescales, or even moderate geological time scales. 600 million years ago the Sun was about 4% cooler. That means over the last 15 million years the Sun's radiation has probably increased by about 0.1%. Oceanic circulation has a major role: as continents move around they alter how the oceans transport and circulate heat. Volcanism also has a significant impact, but that impact is tricky to work out: increased CO2 adds to the greenhouse effect, but other volcanic emissions like dust and SO2 have a net cooling effect on the surface of the Earth. The Deccan traps, for example, is believed to have caused significant cooling during their formation.
Life, on long time scales, also causes an effect, Much of the petroleum the industrial revolution is burning and adding to current CO2 levels came primarily from the Carboniferous period. During that time Earth had a warm and humid climate promoting the development of huge rainforests worldwide. These plants photosynthesized so much carbon out of the atmosphere that CO2 levels dropped from something like 1400ppm to 400ppm. That caused the climate to cool significantly over a few hundred million years until it became colder and drier. The rainforests died off, and with the rainforests gone atmospheric CO2 began to rise again, increasing temperatures again.
Actually, over Earth's history the largest contributors to climate change have been atmospheric greenhouse gases, oceanic circulation currents, and the configuration of the continents. Two of the three are things human activity is demonstrated to be capable of altering on timescales many times faster than they have changed in Earth's history.
Variability in insolation insufficient (Score:5, Informative)
Look at it this way. The variance in solar radiation over a thousand year period is less than 0.01% of the variability seen in global temperature increase during the same period. In other words, the variability in solar radiative output (insolation) is far too small to explain the wide range of variance in global warming since the onset of the industrial revolution. In contrast, increase in carbon dioxide, as expected from the physics of its absorbtion spectrum explains cha.nge in temperature quite well (in fact it explains it rather well over the past 500 million years if isotope data is evalatuated).
It should be noted that there is no 18 years pause in global warming of sea temperature records. In fact, if one uses the arbitrary 18 year intervals to assess global atmospheric climate change, the record still shows global warming. Its just that within the last 18 years it has not been increasing as fast as the average over the last 100. Consequently, no one should be surprised that November 2013 proved to be the warmest November in recorded human history.
Re:What about the Little Ice Age? (Score:5, Informative)
Or you could learn to read what they are actually saying, and stop listening to the made up crap you invent in your head.
Variations in solar output is not the key driver behind climate variation since 1900AD. That's it. Note the decided lack of dismissal of the sun as an energy source, or of the possibility that the sun could have been the primary driver of climate change. People suggested it, so they checked a millennium's worth of proxy data, and they showed a marked disconnect between the trends in solar and climate activity that appears in the last 100 years. This reconfirms similar studies over the last 20 years that have shown the same thing. Science.
Re:Way to state the obvious (Score:5, Informative)
"They aren't saying that the climate is not affected by changes in solar radiation."
That's what they're saying. But they're offering absolutely nothing new here. This is merely a review of others' past (perhaps too long past) work.
What they do say (section 6.4, "climate change", which is their conclusive paragraph) is:
"Extensive climate model studies have indicated that the models can only reproduce the late twentieth century warming when anthropogenic forcing is included, in addition to the solar and volcanic forcings [IPCC, 2007]. The change in solar radiative forcing since 1750 was estimated..."
Here is a plain English translation. (This bit is pretty important.)
"Climate model studies by other people can only reproduce the late twentieth century warming when anthropogenic radiative forcing is included."
This paper actually claims no new evidence that Anthropogenic Global Warming (CO2 AGW) is actually occurring. Their own statements (their own concluding paragraph above if you read the whole thing) says that they are relying on past studies to come to that conclusion. Other people concluded that. And they cite as a reference, an old IPCC report. The newer IPCC report is much toned down from the 2007 version they cite.
Not much to see here, and certainly nothing new, by their own admission. Move along now.
I should also point out that the entire concept of "radiative forcing" this is based on was refuted a few years ago, and so far that refutation has not been successfully challenged.
Re:Way to state the obvious (Score:0, Informative)
Computer models to deal with the ice ages have been around for a while. Geocarb III (Bob Berner - Yale) comes to mind, as well as a few others.
Modern climate models essentially are working on an applied problem (anthropogenic forces) over a narrow domain (1900 - 2100). They don't deal with ice ages because they're not relevant to the time period we're trying to model.
Finally, the last decade was the warmest on record. Hardly a lull over historic averages.
http://bit.ly/19mTk7b
Re:Without the sun there is no climate change at a (Score:4, Informative)
There's a great video by Bill Nye performing this very experiment.
Check it out at result of carbon dioxide in atmosphere [smithsonianmag.com]
What the deniers are claiming is that somehow the bulbs really aren't of equal intensity, which in this experiment is easily shown false since one can place a second pair of thermometers on the top of the vessels at equal distances from their respective lamps and readily demonstrate that for these two thermometers the temperature outside the vessels are the same. Not surprisingly the deniers ignore the findings of the scientific article, which demonstrates that at least for the last 1000 years (of which the last 100 has seen the most warming) solar output has been relatively stable by comparison, with very little variation outside of the usual solar cycles that amounts to less than 0.01% difference in output from maximum to minimum.
Re:Grasping at Straws (Score:5, Informative)
The UK getting record snowfall despite AGWers claiming the UK wouldn't see snow after 2008.
It goes back and forth. In 2000, they were saying that AGW would get rid of snow [independent.co.uk]. In 2008, they were saying the snow was a result of AGW [theguardian.com].
No doubt you will see a reversal again when there is no snow.
Re:That's not a conservative reply (Score:5, Informative)
the now decade long pause in global warming.
Except that's not actually a thing. It's a deliberate misreading of data by people who are lying to you for political reasons. (Specifically, separating out selective readings (variations in surface temps) from broader data which shows a pretty constant heating effect, and falsely presenting the selective readings as "Global temperatures".)
Re:Way to state the obvious (Score:4, Informative)
Arguments refuting this idea are available HERE [climateofsophistry.com] and HERE [principia-scientific.org] (pdf).
Re:Grasping at Straws (Score:5, Informative)
Grasping at straws indeed. This is the map for November, and you're telling me that the AGW folks are grasping at straws?
http://www.ncdc.noaa.gov/sotc/service/global/map-percentile-mntp/201311.gif [noaa.gov]
Re:That's not a conservative reply (Score:5, Informative)
The pause in temperature rise has been written off as merely the effect of solar minimum.
The supposed "pause" is only surface temps, which is caused by the El Niño dominated cycle of the 1990s switching to a La Niña dominated cycle since 2000. This changed the warming pattern from surface dominated to deep ocean dominated (due to the shift in trade-winds exposing different layers of ocean.) This has been known for... well, I've known it for nearly a decade. (It's also known that this normally correlates with a marked cooling of global surface temps (such as in the 1940s), but this cycle is notable that there's still a (slower) rise in surface temps in spite of being a strong "cooling" cycle.)
What is new and interesting is the correlation between the decline in sunspot activity during the same decade as the La Niña dominance. So some researchers wonder if variations in solar activity are a factor in the decadal variation in the El Niño/La Niña cycle.
The is completely different from the research in TFA, which concerns the longer term climate trends, for which there is good correlation with solar output variations across the last 1000 years, except over the last century. The last hundred years are a new thing which needs a factor besides solar variation, the most parsimonious explanation is changes to levels of known greenhouse gases.
Now, it should tell you something about the progress of climate science that the researchers are drilling down and teasing out specific smaller parts of how the climate works in detail; while opponents of the existence of climate change are still stuck on the first page. But I suspect it doesn't.
Re:That's not a conservative reply (Score:4, Informative)
Re:Way to state the obvious (Score:5, Informative)
CO2 has been a major factor in climate for a looooong time, at least as far back as the Cambrian explosion since CO2 is what melted "snowball" earth prior to the Cambrian explosion. CO2 can be both a "feedback" (melting permafrost) or a "forcing" (volcanos, human emissions). When acting as a feedback it always amplifies the direction of the change. We have known about CO2's major role since the 1950's when improved spectrometers finally pinned down it's role in the ice ages, ( Milankovich cycles alone cannot account for the magnitude of the changes observed in the ice ages).
Our best estimates of an important metric called "climate sensitivity" come from Fourier's formula and paleoclimatology (aka-geology). Fourier's formula alone gives ~1.5C rise for a doubling of CO2 but that assumes Earth is an ideal black body, which it is not. Adding geological evidence to estimate the feedback component brings it up to ~3.0C, the error bars are between 1.5c and 4.5C for a doubling of CO2, with the upper limit being far less certain then the lower. The uncertainty at the upper end is due to the lack of knowledge on things like frozen methane in deep ocean beds. The recent IPCC report downgraded the risk from sudden "tipping points" so the current high end estimate of climate sensitivity (whatever it is exactly) has a smidge more certainty than the previous report.
Disclaimer, IANACS, just a layman with a 30yr interest in the subject, don't rely on what my aging neurons tell you, WP is your friend for climate facts and trivia and I'm more than happy to be (politely) corrected.
Re:What about the Little Ice Age? (Score:4, Informative)
Nobody is denying the Sun is (practically) the only source of energy on the Earth's surface including the oceans, land and atmosphere. All they are saying is that the Sun isn't variable enough to account for most of the variability in climate that is seen.
Re:every year we have winter summer cased by sun (Score:2, Informative)
You don't have to go to that extent. Leave Earth & Sol where they are but remove all the greenhouse gases.
Granted, without CO2 there would be no plant life and there would have to be no source of GHGs but if you had a world exactly like ours in this orbit with an atmosphere of only nitrogen, oxygen & argon, it would be too cold to support the current humans and the current flora & fauna.
Re:Yet tiresome denialism will still reign supreme (Score:4, Informative)
A perfect example of Dunning-Kruger at play.
The "hockey stick" was from actual data! D'oh!
Temperatures have risen, and the changes in atmospheric radiative properties have been observed and confirmed for ever.
There was a major prediction about global warming in a Nature article in 1980. The understanding then was substantially less mature and there was no clear-cut observed signal in the data at that time (as we know now, fossil fuel soot was temporarily counteracting increased greenhouse forcing). Since then, observed data have turned out the way that it was predicted then, and the understanding of the fundamental physics then is the same as now.
The predictions are not groundless, and the models aren't wrong.
The hypotheses HAVE been reinforced and confirmed by observable facts, over and over and and over and over and over.
Re:Care to explain the climate change of Mars (Score:4, Informative)
Anyone care to explain what happened to Mars (without the involving the Homo Sapiens Sapiens) ?
Ok, pay attention:
Mars has no magnetic field to divert the solar wind. This, combined with the lower gravity allowed Mars' atmosphere to escape and/or be blown away. There's still a bit left (Mars has wind), but not enough to prevent the water from evaporating.
Now, stop trying to be a smart-ass. Ignorant people trying to be smart-asses just make themselves look stupid.
Re:Way to state the obvious (Score:4, Informative)
You must have missed that whole no warming in 17 years thing.
You must have fallen for the climate deniers' play on public ignorance. The full and correct statement is this: "There has been no statistically significant warming in the past 15 years."
Notice that the word "statistically" is emphasized because it makes all the difference. If you remove it, the statement will be about plain average temperature. But as it is written above with the word "statistically" in place, the statement is about error bars [wikipedia.org] around the average. The longer timespan you measure, the smaller the error bars become. 15 years timespan is just barely too short to make definite conclusions. But 16 years or more is enough and the conclusion is that warming is still ongoing.
Re:Care to explain the climate change of Mars (Score:3, Informative)
The current theory is that Mars, like Earth, at one point had a molten core that spun, thus causing a magnetic field that held an atmosphere.
The core solidified, stopped spinning, the field collapsed and the atmosphere went its merry way off into space.
In other news, just because your house burned down after getting hit by lightning does not mean it's safe for my 3 year old to play with matches.
Re:Grasping at Straws (Score:4, Informative)
You're probably just trolling, but you're currently modded +3, so I'm going to reply.
Such as the US just had one of the 10 coldest years on record.
Minima and maxima are by definition outliers. While there is an entire body of statistical literature on outliers, they're not used to determine trends or draw conclusions, because they are essentially (bad) luck.
The UK getting record snowfall despite AGWers claiming the UK wouldn't see snow after 2008.
Sources please. Because no serious scientist would ever make such a definite statement. A mathematician might, but science, including climate science, is all about statistics and probabilities. In any field. Perhaps you mean this article in the Independent [independent.co.uk]? The scientist quoted says that in 20 years time, snowfall will become a rare and exciting event. So I think that we can consider him proven wrong if it snows in southern England for say, five out of ten years from 2020 onwards?
Antarctica getting within .5 degrees of the coldest recorded temperature on earth.
Antarctica is a huge and largely unexplored continent. Finding a new minimum in a situation where very little information was available is hardly suprising, and certainly shouldn't be used to draw any conclusions.
Along with 2000 record low temperatures recorded over the last couple of months.
Among how many measurements? Record since when? And see above about outliers.
Add that to the IPCC report showing no warming for 17 years.
Indeed. They also investigated why, but you're conveniently leaving that out since it doesn't fit your agenda. I'll give you a hand as to the causes according to the IPCC: an exceptionally quiet sun (there's another of those outliers), several smaller volcanic eruptions increasing the amount of dust in the upper atmosphere, and an increase in dust in the lower atmosphere, probably due to industrial pollution. According to the IPCC, the discrepancy is partially explained by these three causes (which weren't put into the models when the prediction was made), and the remaining difference is small enough to fit within the natural variation (stochasticity) of the models, or be attributed to errors in the models.
Its become pretty obvious which side has been lying. Now they are grasping at straws to report ANYTHING that shows their side "might" be right.
Sorry, this is not the 18th century anymore. Science is a quantitative affair, and necessarily so, because our world isn't binary. The question is not whether there is human-induced climate change, the question is how strong an effect humans are having on the biosphere. Maybe it's small enough to be negligible (probably not, according to what we currently know), maybe it's huge and a danger, but it's a quantitative question.
I'm going to ignore the alarmists and look at the evidence myself. If AGW was real, they wouldn't have to lie as often and at least ONE of their predictions would have happened.
Excellent idea. Try reading the IPCC report [www.ipcc.ch] instead of The Drudge Report and you might find some.
Re:Without the sun there is no climate change at a (Score:4, Informative)
Solar output has been gradually increasing for a long time, and some "skeptics" claim this is the real reason for the climate changes we've observed (ie: not greenhouse gas emissions). But the emerging consensus is that this increase in solar output is nowhere near enough to account for the warming we've seen in the last century.
Re:every year we have winter summer cased by sun (Score:4, Informative)
Water vapor doesn't last enough to be a forcing so it's a feedback. When there a long-lived GHGs, that can raise the temperature enough to evaporate sufficient amounts of water, then its effect becomes large enough that it's dominant.
From http://en.wikipedia.org/wiki/Global-warming_potential [wikipedia.org]
Although water vapour has a significant influence with regard to absorbing infrared radiation (which is the green house effect; see greenhouse gas), its GWP is not calculated. Its concentration in the atmosphere mainly depends on air temperature. There is no possibility to directly influence atmospheric water vapour concentration