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Scrodimite 6 points ago +6 / -0

I was watching some video where a guy explained the impact solar cycles had and how they started the ice ages etc. It kind of made sense, I mean any impact humanity has on the planet is going to be absolutely dwarfed by the star that has enabled life and weather to exist here in the first place. Maybe its right, maybe it's wrong, who knows? Interesting to think about anyways.

PantySoup69 3 points ago +3 / -0

The sun beating on his bald head has made his brain shrink.

RightOfSask -3 points ago +3 / -6

They have nothing to do with the current change. Solar irradiance (speak the energy in W/m² we get from the sun) is as high today as it was 100 years ago.


BeetlejuiceForSenate 5 points ago +6 / -1

That graph is the leading image on the Solar activity and climate Wiki page. The temperature is modeled as a rate of change in degrees C, and the irradiance energy in W/m² is modeled in absolute value. The thick lines are averages. The total solar irradiance (TSI) data has large peaks and troughs after 1950. I mention this because the way the data is presented doesn't really tell the whole story, it's designed to not show correlation.

The TSI before 1970 is modeled on reconstruction analysis from this paper, extrapolating TSI based on the earth's magnetic flux. Interestingly that paper models TSI from 1700-1970 but this chart starts in 1880. That leaves out nearly 200 years of available data, which to me suggests cherry picking. Based on that paper TSI is high before 1880, while also other data sets suggests global temperatures were lower. Before 1880 anthropogenic CO2 emissions were low. This suggests that factors other than only TSI and CO2 play a role.

This paper, Long-term global temperature variations under total solar irradiance, cosmic rays, and volcanic activity, suggests that "there are combined effects of solar, cosmic rays, geophysical and human activity on climate change patterns. It should be noted that more detailed investigations of such complex interactions are necessary."

RightOfSask 1 point ago +3 / -2

and the irradiance energy in W/m² is modeled in absolute value.

If the solar irradiance was modeled as change, it would have gone down in the last few decades. It wouldn't make much sense to say that lower solar irradiance (speak less energy from the sun) leads to a higher global temperature.

Long-term global temperature variations under total solar irradiance

What we currently see is a high short term temperature increase, while the solar irradiance decreased slightly. The exact opposite effect should be the case.

BeetlejuiceForSenate 4 points ago +4 / -0

It wouldn't make much sense to say that lower solar irradiance...leads to a higher global temperature

Not at first glance, and I don't disagree with you. I'm only pointing out that graph paints a narrow picture and conclusions shouldn't be made based from that alone. This is a complicated scientific issue which has sadly become very politically charged.

If global temperature was directly correlated to TSI, large spikes of irradiance would be offset by large depressions of irradiance in change of global temperature. This is not the case so this is not the only factor. That is not to say however that TSI is not a factor in relationship with other variables.

The paper Long-term global temperature variations... examines the relationship between these variables. The greenhouse effect (from a combination of sources (to varying degrees), anthropogenic and natural) might explain changes in global temperature not falling during lower levels of solar irradiance. This is not say that solar irradiance has nothing to do with climate change (it does!), only that there is not a direct correlation.

Anyways the linked CTV article isn't about TSI but solar flares and earth/moon orbits, which have a more tenuous link if at all to climate change. Interestingly I've seen some papers years ago examining solar flares interaction with the earth's magnetic field which might be worth investigating. Anyways OP's title is a bit misleading which might be why we've gone down this tangent!

brutanana_dilewski 4 points ago +4 / -0

This is a complicated scientific issue which has sadly become very politically charged.

You could apply this to climate change in general.