The article does not really suggest that the variation must be related to climate change, and mainly simply reports an interesting result with the need for more

The article does not really suggest that the variation must be related to climate change, and mainly simply reports an interesting result with the need for more data. I suspect (though open to be corrected) we already know about plenty of weather features that can regularly vary by 1% over ten year periods, climate change or no climate change. (The annual minimum Arctic ice area, by comparison, shrunk by something like one-third in the same time period, although it has stalled the last few years.)