Why Permafrost Is Thawing, Not Melting

Soil CO2 production in upland tundra where permafrost is thawing

[1] Permafrost soils store nearly half of global soil carbon (C), and therefore permafrost thawing could lead to large amounts of greenhouse gas emissions via decomposition of soil organic matter. When ice-rich permafrost thaws, it creates a localized surface subsidence called thermokarst terrain, which changes the soil microenvironment. We used soil profile CO2 measurements to understand the r...

Arctic Landscapes in Transition: Responses to Thawing Permafrost

Stability Results for Convection in Thawing Subsea Permafrost

Penetrative convection is investigated in a porous medium bounded above by the ocean bed and below by the interface of the thawing permafrost ground. Such convection ow is observed oo the coast of Alaska. The physical model for the thawing subsea permafrost is that of Harrison and Swift 8], with the eld variables: the brine velocity, the temperature and the salinity. We simplify the problem by ...

Discovery of a novel methanogen prevalent in thawing permafrost.

Thawing permafrost promotes microbial degradation of cryo-sequestered and new carbon leading to the biogenic production of methane, creating a positive feedback to climate change. Here we determine microbial community composition along a permafrost thaw gradient in northern Sweden. Partially thawed sites were frequently dominated by a single archaeal phylotype, Candidatus 'Methanoflorens storda...

Why the melting layer radar reflectivity is not bright at 94 GHz

[1] At 94 GHz, the highest radar frequency used for atmospheric research, no radar bright band is observed at the melting layer. In this study, simulations of a vertical profile of melting particles and their scattering properties for a variety of melting particle models are used to capture the basic features of the radar reflectivity structure at 94 GHz in the melting layer. Observations of st...