Scientists are well aware of this. You say it as though it disproves the predictions made in the article, but you haven't said how. Particularly since the predictions take your fact into account.
From that article: "But these effects are very small, and Antarctic sea-ice levels have increased only marginally. In the coming decades, climate models suggest rising global temperatures will overwhelm the other influences and cause Antarctic sea ice to scale back, too."
If the Antarctic sea ice increase is "very small" and just "marginal," then how is Arctic sea ice decrease not also marginal?
Antarctic sea ice is now 1.3 million sq km above the 1979-2008 mean (19% above the mean).[1] Arctic sea ice is now 0.59 million sq km below the mean (4.8% below the mean). [2]
Derivatives. Instantaneous size doesn't matter. You have to measure how they are changing. Furthermore the physical (not climate) models based on these rates of change suggest that right now at this moment the rate of addition of new material to the ice sheet will not matter because the rate of melting to this point has made it unstable and the process of adding additional material will not be able to counter the processes of melting.
http://www.livescience.com/23333-antarctic-sea-ice-global-wa...