I have written on this subject before. Arctic amplification is a secondary effect of climate change, where global warming in the summer increases the temperature by more than twice as much in Polar Regions. A major concern from this is that it accelerates melting of the polar ice caps.
Unfortunately, rising oceans are not the endpoints of the risk from arctic amplification. Another effect, with a strong positive feedback element, may even be worse in the long run. Two recent articles and papers in Science describe this effect. The following text is from a summary of the main paper.
Vast amounts of organic carbon are stored in Arctic soils. Much of this is in the form of peat, a layer of decomposing plant matter. Arctic wildfires release this carbon to the atmosphere as carbon dioxide (CO2) and contribute to global warming. This creates a feedback loop in which accelerated Arctic warming dries peatland soils, which increases the likelihood of bigger, more frequent wildfires in the Arctic and releases more CO2, which further contributes to warming. Although this feedback mechanism is qualitatively understood, there remain uncertainties about its details.