molly -- I more than agree with your "yow!," and I'll raise you a "yowza!"
to Lori_k and the rest of the climate change doubters, I have a few comments. first, I'm a paleoclimatologist. this means that I was looking forward to the new IPCC report like most people look forward to the super bowl. (or like we look forward to the start of ski season!) I want to keep this forum as friendly and awesome as possible, but I just NEED to inject a little science into this discussion, because I can't in good conscience just scroll on by.
I personally work largely with marine geochemistry, but I have fingers in various other climate pies -- stalagmites (speleothems), sediment records, that sort of thing. so the first thing I want to tell you is that there is not just 100 years of observational records and a little bit of ice information. there is an overwhelming preponderance of data, from all over the planet. all the continents, all the ocean basins. this data comes from ice (from air bubbles trapped in glaciers), from tiny, tiny microfossils in deep-sea sediments, from oxygen isotopes in stalagmites from caves, from tree rings, you name it. we currently have a very good climate record going back half a million years or more (visit
https://epa.gov/climatechange/science/images/co2-temp.gif for an excellent graph showing just that).
second, you're absolutely right that there are indeed natural climate fluctuations. however, the natural fluctuations do
not explain the shifts we've seen recently. are there variations in earth's orbit, solar intensity, etc? absolutely. but a look at plots of global temperature show that we are moving way, way out of whack with those fluctuations. furthermore, we're concerned just as much with the alarming rate of change (a degree in 100 years? that's enormous!) as with the
third, you're also right that a chance of a degree or two doesn't sound like much. however, the difference between the last glacial period global average temperature and the right-now global average temperature is only about 6 degrees (C) (that's about a 12.5 F difference). the climate is a delicately balanced place, and it only takes a shift of a few degrees to cause serious changes.
I'm glad we all agree (because of climate change or otherwise) that it's crucial to conserve, to cut down emissions, etc. and I think we also all agree that a certain dose of skepticism is important, and even necessary to weed out the true bits from the political ones. but I just wanted to go on record that the is-global-warming-really-happening phase of scientific discussion is over and has been for a long time. there is absolute agreement that we
are warming up the planet, that it's bad, and that it needs to stop.