Where to begin on this......
I suspect that there is not enough time for me tonight to look up reference information to try and bring the article into context. There are figures in there that are, as far as I can see, pretty much meaningless.
But the quote that really needs checking out is "As a scientist, I know that this is unprecedented in at least as much as 1,500 years. It is truly amazing - it is a huge dramatic change in the system," Dr Hansen said."
More information needed. A lot more.
Is there something worth worrying about? Not based on this article there isn't, no. There is something worth more time and resource investigating.