What Problems are caused by the melting of permafrost?

The permafrost is the perpetually frozen peaty bogs of northern areas like Siberia or Canada's Nunavut.When the frozen material is melted several things happen:

• Trapped methane is released to add to the climate change problems
  
• Building, pipelines and rads sink into the soupy thawed mess
  
• Animals and people cannot pass over the thawed areas disrupting transportation, hunting and animal migration
  
• Erosion near the ocean, lakes and rivers increases.