How much have temps risen in the last 100 years?
Temperatures have risen < 1° C. Yep, that's it. This is science fact. Not fiction. And it's all perfectly normal for our planet.
Temperatures have gone through nearly two complete cycles of warming and cooling over the last 100 years. During the period 1900 to 1940 temperatures were increasing. Then from 1940 to 1975 temperatures were decreasing. Currently, temperatures are increasing back to about where they were in the 1930's.
Overall, the total average annual temperature increase in the last century is so slight the actual amount is uncertain -- maybe 1/3° C.