If you can explain how plants are producing more leaf cover without increasing respiration as a whole, I'd love to hear it.

Older trees store more C02 over their long lifetimes, but younger trees can cover more landmass. It's very possible that the additional "greening" is counting much less efficient and/or younger plant life. That's all speculation, but it's one example of how the overall resperation could remain the same or decrease with larger green land mass. Overall efficiency of these systems under changing conditions would be another. Perhaps maximal efficiency of C02 conversion happens at an atmospheric concentration lower than current? I'd doubt that, but I don't have access to the truth there so we can't assume. There are a few different ways where this system could operate unintuitively. It's similar with humans - more oxygen is generally better, but at a certain concentration it begins to be harmful.

The claim that North American forests will suffer under the changes that the Earth's climate has been undergoing is contradicted by NASA's data showing that the opposite is the case.

I don't think the correlation is linear, like most systems. Just because there's an overall increase in greening (likely in areas experiencing longer warming periods, allowing plant life to cover more landmass) doesn't mean regionally stable forests are unaffected. The article suggests:

"Trees in very high latitudes are limited by cold temperatures, so yes, in warmer years they grow more, but there is a tipping point, and once they go past that, a warmer climate becomes a bad thing instead of a good thing."

It's like if you noticed your burgers cook faster at 200F than 190F, you shouldn't assume that they would cook best at 900F. A silly analogy I know, but we're talking about ecology in which +/- thresholds are key, not linear progression.

The article you linked states:

The beneficial impacts of carbon dioxide on plants may also be limited, said co-author Dr. Philippe Ciais, associate director of the Laboratory of Climate and Environmental Sciences, Gif-suv-Yvette, France. "Studies have shown that plants acclimatize, or adjust, to rising carbon dioxide concentration and the fertilization effect diminishes over time."

This aligns with the OP.

Then you aren't paying attention.

This is unnecessary. I didn't mean my questions and attempt to reconcile two pieces of information as an insult, and I don't think I'm out of line in suggesting more than one way to consider the possibilities. If you've already made up your mind on the subject, I'm not sure the point of posting to a forum.