That was my point. The global warming advocate says that there is no die-off in the tropics and that is proof that the die-off in the Northeast is man made. The skeptical scientist in the article had already pointed out that autumn might explain the die-off in the Northeast. The article calls the skeptic "discredited global warming skeptic". The article was obviously intended for humor.
Here is the paragraph that contains the questionable argument:
When contacted for comment on the new results, discredited global warming skeptic Dr. John Michaels told this reporter, "I think the NASA scientists should investigate the possibility that this die-off is directly related to decreasing levels of sunlight and the resulting cold temperatures as winter approachers". When told of Dr. Michaels' theory, Jorgeson replied, "Well of course he would say that…everyone knows he is in the pocket of 'big oil'. Besides, how else would you explain the fact that the die-off does not occur in tropical locations, where heating oil use is virtually unheard of?"
Yes, I know it was humor, albeit, poor humor. :)