::::::::Well, then.  So you HAD heard of him prior to this thread and precisely for the work that is applicable here.
  
As for the "impact" part of your statement it is entirely irrelevant to the question at hand.  As a journalist he is not expected to have an "impact", he is merely expected to report on it ... which he does as a professional employed by a prominent national Canadian news outlet.  When we quote writers from say, The New York Times or the Washington Post, we don't question whether the authors of those pieces have "impacted" the debate or not because it is merely their reporting on the people who DO have an impact that matters.

You can't deny that he has written extensively on the subject of GW Deniers, his record is there for all to see, and this makes him particularly relevant to the specific criticisms that he raises, namely the methods used by opponents of the GW Deniers to smear and misrepresent them.  Thank you for making my point.