Interesting article.
One thing that stuck me as being perhaps in omission in the article (maybe not in the actual research report, I haven't looked): Warming hastens the hydrological cycle. This is why tropical areas are typically lush from rainfall, and the world's largest desert is in Antartica. Also, eras of past that were hotter than we are today tended to be wetter, and colder times tended to be drier (with exceptions). Maybe the conjunction of "a little warmer" and "a little wetter" add together to make more fire risk; this I don't know.
