Climate change alarmism is certainly a real effect, and is most apparent whenever a new 'weather record' is set (e.g. "hottest July on record", "wettest Labour Day since JFK's death", "most active hurricane season since the last one", etc.), when frequently some pundit - and infrequently an actual climatologist - has a microphone shoved in his face and is asked "Is this due to Global Warming?". A good climate scientist will probably end up on the editing-room floor for pointing out that it's pretty hard to make a convincing argument for an increasing trend in a time-series of global averages from a single data point.
Naysayers do much the same only in reverse. A local cold spell or a single decreasing trend (of whatever magnitude and duration) is instantly the death-knell for anthopogenic climate change and/or global warming in general.
It's a single paper, with problems. It's not the smoking gun that did for GW, any more than last year's hurricane season was proof positive that climate change is going to wipe Florida off the map!