And I actually understand the link you provided. Here is a hint, ignore the left column (for now, we will come back to the left column) and look at the numbers from 1990 to today, aka 25 years. Notice in all 3 examples we had a ph drop of 0.05 to 0.1.
I told you to ignore the first 3 graphs on the left side for they are measuring something completely different than the graphs on the right side. The right side measures ph, the left side measures carbon dioxide concentrations in the earth's atmosphere.
Yet due to the fact the graphs share similar colors sometimes people forget the graphs on the left side and the graphs on the right side are showing different things and all they notice is the graphs show different directions where one is going up and the other is going down.
But there is a reason why this occurs, higher carbon dioxide in the air leads to more acidity in the oceans, and since lower numbers in the ph scale represent greater acidity these left and right sides are actually showing the interconnected relationship of two different functions.
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In other words you just proved my point.