Does the sun have an impact on climate change? How strong is the influence? Is there any influence at all?
In this post I am going to find answers to these questions, which will bring me closer to the answer for my main question. How strong is the human influence on climate change?
To start with, solar variability is quite difficult to measure. There are measurements from satellites since 1979, which shows a variation of ca. 0,1%. But it is difficult to interpret the results; you have to make an approximate estimation to erase false measurements and it is just a short-term observation, which makes this method imprecise.
Therefore, you can’t make a scientific statement, with just this method, concerning the connection between solar variability and climate change. (Joanna D. Haigh 2002)
But satellite measurements are not the only thing we can use to make a statement concerning the solar activity. Since 1600 scientist have recorded the number of sunspots (dark patches on the sun) and faculae (bright patches on the sun) and had connected them to the TSI (total solar irradiance). (Joanna D. Haigh 2002)
Figure 4: Joanna D. Haigh 2002
Without bothering you with physical details, how they actually accomplished that. You can all see, there is just a small correlation between the TSI and the surface temperature on the earth. But it is uncertain how strong this actually influences our climate. Mostly, because of unmentioned factors like volcanic eruptions or El Nino, which could have affected the climate as well. (Joanna D. Haigh 2002)
In this post, I just worked with one paper from Joanna D. Haigh 2002, so it is just one opinion and I just scratched the surface of the article, but I hope, I got the main points right.
I will end with a statement of the conclusion, which summarizes my post quite good.
“The warming that occurred during the latter half of the 20th century
cannot be ascribed entirely to solar influences.“(Joanna D. Haigh 2002)