Thank you for that question.
Yes, in every individual chapter you must have agreement. Some people will make a big deal that there's no such thing as consensus in science, but in fact there is. There's consensus that we're going to use words such as “likely” and “very likely”, which have a probability attached to them. You'll find that when you come to consensus, the extremes are not there. This is a very conservative report.
In fact, people have actually studied the results and the predictions, projections, from the IPCC, since its first report in 1990. They looked at what has actually happened over the last two decades, since IPCC started issuing their projections. You'll find that what happened was within the bounds projected by IPCC, but at the upper end of those bounds.
So you should view the IPCC projections as being very conservative, although not in the political sense. It's conservative in that it's not alarmist; it's very middle of the road and good science by the world's best scientists.