How we know that the sun changes climate (II). The present
Posted on May 17, 2024 by curryja | 42 Comments
by Javier Vinós
Part 2 of a 3-part series. Part I is here.
The effect of the Sun on climate has been debated for 200 years. The basic problem is that when we study the past, we observe strong climatic changes associated with prolonged periods of low solar activity, but when we observe the present, we are able to detect only small effects due to the 11-year solar cycle. There are several possible explanations for this discrepancy. But the main question is how the Sun affects climate.
In this article we examine the effects on climate caused by the 11-year solar cycle over the last few cycles and their relation to recent climate change.
The IPCC Says…
In its 5th Assessment Report, the IPCC used climate models to calculate the Sun’s contribution to warming. These models only take into account changes in the total energy coming from the Sun, which is known to vary by only 0.1%. Therefore, the IPCC’s answer is that the Sun has contributed nothing to the warming.
This is absurd given our knowledge of past climate and the fact that we passed through a 70-year solar maximum in the 2nd half of the 20th century, one of the most active periods of solar activity in thousands of years.
https://judithcurry.com/2024/05/17/how-we-know-that-the-sun-changes-climate-ii-the-present/#more-31234
