"the National Academy of Sciences report, Climate Change Science: An Analysis of Some Key Questions, begins: "Greenhouse gases are accumulating in Earth's atmosphere as a result of human activities, causing surface air temperatures and subsurface ocean temperatures to rise" [p. 1 in (5)]. The report explicitly asks whether the IPCC assessment is a fair summary of professional scientific thinking, and answers yes: "The IPCC's conclusion that most of the observed warming of the last 50 years is likely to have been due to the increase in greenhouse gas concentrations accurately reflects the current thinking of the scientific community on this issue" [p. 3 in (5)]."
"Global mean temperature continues to increase for hundreds of years at a rate of a few tenths of a degree per century after concentrations of CO2 have been stabilised, due to long time-scales in the ocean....If greenhouse gas concentrations were stabilised (even at present levels), sea level would nonetheless continue to rise for hundreds of years....The loss of a substantial fraction of the total glacier mass is likely. Areas that are currently marginally glaciated are most likely to become ice-free."
Both the National Academy of Sciences and the IPCC are essentially political organizations (in the sense that their purpose is to inform policy, I don't mean to suggest that they are partisan) and what they say should not be conflated with the scientific literature on climate change.
Scientists are working very hard to understand past and future climate change, but it is an incredibly complex problem. (For analogy, can political scientists predict who will be elected president in 2012?...it's possible to make some good guesses but there are a lot of factors and it's hard to know what will happen.)
Sure, there is general agreement on some points and organizations such as the IPCC are doing a noble job of trying to synthesize the mountains of complex science into a few simple statements, but I think you are drastically oversiplifying the case when you say that
"99.99% of the world's scientists, based on careful interpretation of many thousands of peer-reviewed studies, agree that global warming is real, and is caused by human activity. A vanishingly small handful of scientists happen to disagree with this assessment, based mostly upon their opinion and politics."
Yes, it's a complicated problem, but there's a heck of a lot more than just "general agreement."
When it comes to the two central questions (is global warming real? is it caused by human activity?) the situation is just overwhelming: very nearly all of the published literature is in agreement that the answer to both questions is "yes".
There is certainly less unity on other questions related to climate change, but it's misleading to suggest that there's any significant scientific disagreement on the issue.
What caused the earth to get warmer?
"the National Academy of Sciences report, Climate Change Science: An Analysis of Some Key Questions, begins: "Greenhouse gases are accumulating in Earth's atmosphere as a result of human activities, causing surface air temperatures and subsurface ocean temperatures to rise" [p. 1 in (5)]. The report explicitly asks whether the IPCC assessment is a fair summary of professional scientific thinking, and answers yes: "The IPCC's conclusion that most of the observed warming of the last 50 years is likely to have been due to the increase in greenhouse gas concentrations accurately reflects the current thinking of the scientific community on this issue" [p. 3 in (5)]."
Will it continue?
Directly from the IPCC report:
http://www.grida.no/climate/ipcc_tar/wg1/035.htm#temperature
"Global mean temperature continues to increase for hundreds of years at a rate of a few tenths of a degree per century after concentrations of CO2 have been stabilised, due to long time-scales in the ocean....If greenhouse gas concentrations were stabilised (even at present levels), sea level would nonetheless continue to rise for hundreds of years....The loss of a substantial fraction of the total glacier mass is likely. Areas that are currently marginally glaciated are most likely to become ice-free."