The Yukon river goes through periods of freezing and unfreezing during the year, and when it isn’t frozen, the riverbank and areas around it are eroded quite easily. This leads to large amounts of phosphorus entering the water and eventually flowing into the Arctic Ocean. Permafrost is already wearing downs in this area, and is completely changing the way ecosystems work in the northern hemisphere. The changes of mineral composition in the water will cause huge changes within the entire Arctic and may have consequence for the carbon cycle, animal and marine life habitats, and other important parts of the ecosystem.
In general, the thawing of the permafrost is clearly an effect of global warming. The temperature has been getting warmer, and the permafrost has been melting increasingly faster because of this. This thawing can cause huge problems for people in Alaska because permafrost makes up a major part of their landscape. They usually only get a few inches of precipitation per year, but frozen layer provides a sort of safety net for the water, and makes the water sit at the surface which nourishes that plants. Furthermore, there are certain plants that actually insulate the permafrost and keep it from melting. If the temperatures keep increasing, the permafrost will melt little by little, and won't be able to sustain these insulating plants. They in turn, won’t be able to insulate the permafrost anymore which will lead to it melting even more.
I think that there are many global issues that are important, but we hear about them in the news all the time. It's very unusual to hear a major news story about a specific effect of global warming in a certain area. I've never heard a story on the news about Alaska and I think it's important to bring awareness to effects of global warming that are less known.