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Sun Not a Significant Driver of Climate Change
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."
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.
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.
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.
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. In 2008, they were saying the snow was a result of AGW.
No doubt you will see a reversal again when there is no snow.
"First they came for the slanderers and i said nothing."
Agree that the Sun is the source of all the energy in the climate. The composition of the earth's Atmosphere, oceans and crust, have been likened to the "thermostat" in that they can absorb or reflect that energy to varying degrees.
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.
And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.