ENVIRONMENT: PERMAFROST THAW & CARBON FEEDBACK LOOPS Arctic permafrost contains approximately 1,700 gigatons of organic carbon—roughly twice the amount currently in the atmosphere. As global temperatures rise, thawing permafrost releases methane and CO2, accelerating warming in a positive feedback mechanism that wasn't fully factored into earlier climate models. Current thaw rates in Siberia are 3-4 times faster than global average, with regions like the Yamal Peninsula losing up to 2 meters of ground elevation per decade. This matters because permafrost degradation represents a tipping point beyond human control: once triggered, the carbon release becomes self-sustaining regardless of emissions reductions, potentially adding 0.13-0.27°C to warming by 2100—equivalent to decades of current global emissions policy efforts.