A blog item discusses melting permafrost and existential dispair.  Someone in the comments is just asking questions:
"Also, how is the report of melting permafrost different from a conservative saying that a particularly cold winter disproves the climate change?" 
What is your answer?
There is an answer in the thread , but it isn't helpful: it doesn't address the question, it wanders all over the place, and it's hard to understand (to be fair, I suppose, the first sentence does sort of point towards what I think is the right answer).
My answer is the difference is the same as the difference between long-term trends and short-term fluctuations. Permafrost melts due to year-after-year temperature increases and means possibly significant change. Freakish weather is a happenstance due to particular circumstances and doesn't mean much past its own existence.
"I appreciate SDF but it's a general-purpose server and the name doesn't make it obvious that it's about art." - Eugen Rochko