The least generous interpretation of that is that this one event ought to convince all my friends of AGW. Now somehow the climate change topic is an ongoing co

The least generous interpretation of that is that this one event ought to convince all my friends of AGW. Now somehow the climate change topic is an ongoing conversation with a heck of a lot of things said about it. You can't summarize it all in a comment, and in any case this is an introductory statement meant to take the reader to the main issue, which is how evidence is supposed to work. I would suggest a more generous interpretation is "evidence such as this has been piling up for quite some time and yet does not change minds".