Assuming the measurements are accurate. Arriving at a global mean temperature is voodoo enough, but when you place your surface temperature measuring stations beside air conditioning unit exhaust vents you have to wonder if the temperatures even reflect reality. Most of these stations surveyed have a margin of error in recording temperatures of more than 2C... while your measured catastrophic increase is 0.6C?? Next stop, measuring your member with an unmarked ruler. "Hey, it's about a foot long. Really!!"
I certainly agree that some of the surface measurement sites are situated poorly. However, given that "changes in borehole temperatures (Section 2.3.2), the recession of the glaciers (Section 184.108.40.206), and changes in marine temperature (Section 220.127.116.11), which are not subject to urbanisation, agree well with the instrumental estimates of surface warming over the last century" and that there is no statistically significant difference between the records from rural and urban surface temperature stations ("While there is little difference in the long-term (1880 to 1998) rural (0.70C/century) and full set of station temperature trends (actually less at 0.65C/century), more recent data (1951 to 1989), as cited in Peterson et al. (1999), do suggest a slight divergence in the rural (0.80C/century) and full set of station trends (0.92C/century) However, neither pair of differences is statistically significant.", as detailed in the IPCC report, it doesn't, well, appear to be statistically significant. Oh, and could we omit the petty attempts at vulgar "humor"?
We're now glossing over point 2 and making broad assumptions. Nevermind that "To the consternation of global warming proponents, the Late Ordovician Period was also an Ice Age while at the same time CO2 concentrations then were nearly 12 times higher than today-- 4400 ppm. According to greenhouse theory, Earth should have been exceedingly hot. Instead, global temperatures were no warmer than today. Clearly, other factors besides atmospheric carbon influence earth temperatures and global warming." [Source] Hmmm... what's the phrase I'm looking for here... something about correlation and causation.
Perhaps you ought to take a look at this study. I quote: "The answer: This particular ice age didn't begin when CO2 was at its peak -- it began 10 million years earlier, when CO2 levels were at a low." "Taken together, the evidence suggests that the ice began to build up some 10 million years earlier than when volcanoes began pumping the atmosphere full of the CO2 that ended the Ordovician ice age."
"Our results are consistent with the notion that CO2 concentrations drive climate."
May want to update your talking points...though I rather suspect you'll regurtitate the same set the next time a climate change discussion comes up here.
This last one brings us to the ultimate death blow to the global warmers' argument. The warming we've experienced since the last glacial period has brought us grasslands, forests, jungles.... When the next glacial period comes, the planet will be covered mostly by icy tundra and extreme deserts again. Warming has only made this planet MORE habitable to us. I've got 12000 years of proof that warming is good. What do you have to the contrary?"
Dude...are you being deliberately obtuse? It's not just sea levels rising due to glacial melt, though that alone is problematic (though there's this thing called empathy where some humans sympathise with the plights of other humans...something you apparently lack). Potential consequences also include droughts, heat waves, disruption of various ecosystems, increased oceanic acidification due to greater CO2 absorption (up to a limit) and so many others. If you were genuinely interested, I could go into the details.