Well, I have a different opinion about the near future, and likely the recent past, but am glad to see that you are open minded about the state of the science. I do wish the IPCC would consider what the sun is up to in all this, but that is not in their interests perhaps. Instead its dire prediction after dire prediction, the anticipated dates of some of them are now past, yet those failures don't get much air time. There were 4 hurricanes on year that came into the East Coast of the US. These were blamed on global warming with dire predictions of more more more. Instead hurricanes are now very few. Fifty million climate refugees, polar bears the habitat of which they know nothing, endless freakin drama that is not science but hysteria, why? I hope that soon things make the hard turn to cold just so the can get their drama right, because cold is worse. Don't know how they are going to blame it on humanity but they will find a way. They shifted gears from global warming to climate change fairly flawlessly and are trying to bury the "pause" in the deep oceans, so one must give credit where its due. Still if the cold that I anticipate occurs, I'm sure it will somehow be our fault.
Anyway I better give it a rest.
The IPCC report is not a hysterical document. It has low confidence in predictions about what will happen with regard to hurricanes and other storm systems, and in general it actually seems more likely that they'll become less frequent (but more severe when they do happen). Sea level rise by 2100 is predicted to be less than a meter even under high-emissions scenarios. It does state that shifting precipitation patterns causing droughts, more heat waves and fires, and sea level rise are likely to cause stress on human society and on ecosystems, but there's nothing apocalyptic about it at all. The most dire things you hear are generally from activists, not scientists, although there are a few like James Hanson who cross that line.
It actually has been considered that solar activity might be entering a minimum, and climatologists have looked at what would happen if solar output were to decline to the same levels it was at during the
Maunder Minimum of 1645-1715, where sunspots virtually disappeared and the worst part of the Little Ice Age occurred.
This paper simulates exactly this and finds that the effect would be a reduction in global temperatures of no more than 0.3 C, and most likely substantially less. This is approximately a tenth of what is expected to happen with a doubling of CO2. Other sources I found seem to agree as well.
There are other reasons to believe this. Here's a figure from the IPCC report, which I'll explain below:
What it's saying is that a bunch of reconstructions have been made based on data ranging from sunspots to radioactive isotopes produced by cosmic rays. All of the reconstructions have shown the total amount of solar radiation that reaches the sunlit side of the Earth (the solar constant or Total Solar Irradiance (TSI)) has varied by about 1.8 W/m^2 between the Maunder minimum and the largest recorded activity maximum around 1950.
There’s a wrinkle I’ll explain here. This ~1361 W/m^2 gets spread over the Earth's surface, including the dark half, and not as much reaches the poles as the equator; the effect is that the average over the whole surface of the Earth is ¼ of the amount at the equator on the sunlit side (which is what the TSI really is). Then 29% reflects back to space. So the amount of energy actually absorbed is 1361*0.71/4 = 242 W/m^2, and the variation since the Little Ice Age is 1.8*0.71/4 = 0.32 W/m^2. That’s from the modern maximum to the Maunder Minimum; at the moment we’re in between the two, so if we suddenly lost 0.32 W/m^2 we would be getting even less energy than during the Little Ice Age.
The amount of extra heat trapped by the amount of CO2 we have emitted so far is known fairly well; the IPCC estimates it as 1.68 W/m^2, with a range of 1.33 to 2.03. That’s not based on any projections; it’s true at the present time. As you can see, this dwarfs the 0.32 W/m^2 reduction we could expect if the sun suddenly shifted to a grand minimum of solar activity worse than in the Little Ice Age. Even if your prediction that we’re about to enter a severe solar minimum comes true, we’re still going to warm, just a little bit more slowly.
A dose of political science please!
