Permafrost warming has the potential to amplify global climate change, because when frozen sediments thaw it unlocks soil organic carbon. Yet to date, no globally consistent assessment of permafrost temperature change has been compiled. Here we use a global data set of permafrost temperature time series from the Global Terrestrial Network for Permafrost to evaluate temperature change across permafrost regions for the period since the International Polar Year (2007–2009). During the reference decade between 2007 and 2016, ground temperature near the depth of zero annual amplitude in the continuous permafrost zone increased by 0.39 ± 0.15 °C. Over the same period, discontinuous permafrost warmed by 0.20 ± 0.10 °C. Permafrost in mountains warmed by 0.19 ± 0.05 °C and in Antarctica by 0.37 ± 0.10 °C. Globally, permafrost temperature increased by 0.29 ± 0.12 °C. The observed trend follows the Arctic amplification of air temperature increase in the Northern Hemisphere. In the discontinuous zone, however, ground warming occurred due to increased snow thickness while air temperature remained statistically unchanged.

The results of the International Permafrost Association's International Polar Year Thermal State of Permafrost (TSP) project are presented based on field measurements from Russia during the IPY years (2007-09) and collected historical data. Most ground temperatures measured in existing and new boreholes show a substantial warming during the last 20 to 30 years. The magnitude of the warming varied with location, but was typically from 0.58C to 28C at the depth of zero annual amplitude. Thawing of Little Ice Age permafrost is ongoing at many locations. There are some indications that the late Holocene permafrost has begun to thaw at some undisturbed locations in northeastern Europe and northwest Siberia. Thawing of permafrost is most noticeable within the discontinuous permafrost domain. However, permafrost in Russia is also starting to thaw at some limited locations in the continuous permafrost zone. As a result, a northward displacement of the boundary between continuous and discontinuous permafrost zones was observed. This data set will serve as a baseline against which to measure changes of near-surface permafrost temperatures and permafrost boundaries, to validate climate model scenarios, and for temperature reanalysis.

Recent years of increasing air temperature in the Arctic have led to a significant increase in the rate of retreat of permafrost coast, which has threatened livelihoods and infrastructure in these areas. The Kara Sea hosts more than 25% of the total Arctic coastline. However, little is known about how coastal erosion in the Kara Sea may have changed through time, and the climatic and environmental drivers remain unclear. Here we study coastal dynamics along a 4-km stretch of permafrost and sea-ice-affected coastline in south-west Baydaratskaya Bay of the Kara Sea, western Siberia, between 2005 and 2016, by using handheld differential GPS mapping and satellite imagery.We identified temporal and spatial variations in the retreat rates, ranging between 1.0 (+0.1/−0.6) and 1.9 (+0.7/−1.3) m/yr over the studied coastline during 2005-2016. We also made ground temperature measurements, subsurface resistivity measurements and estimates of wave energy flux of wind-driven ocean waves, to investigate the dominant climatic factors influencing the observed retreat rates through time. We found that wind-driven wave activity during sea-ice-free days influences the magnitude of coastal retreat in the study area, while recent temperature rise has contributed less to enhancing coastal retreat during the study period. This suggests that the amount of eroded sediment and the associated release of nutrient to the nearshore zone are controlled by the magnitude of wave activity, which may influence infrastructure along the permafrost coast and marine ecosystems in the proximal ocean.

The natural and human-induced explosive processes in the permafrost area were studied. A new approach is proposed to the theory of formation of gas emission funnels. It is based on the mechanism of migration of gas fluids from the gas hydrates dissociation zone to the overlying permafrost. The dissociation zone is formed in the areas of local heating due to the heat input from above. The preparation stages of the explosive process that formed the Yamal crater are shown. The preparation phases of natural explosive processes have been identified and characterized. Different scenarios are considered for the preparation of natural explosive processes in the cryolithozone. The main conclusions of the conducted research are the following: the explosions of hydrolaccoliths and the formation of gas emission funnels belong to one group of processes, i.e., physical explosions of natural origin; preparation of explosive processes in the permafrost goes through several stages; the migration of gas fluids plays an important role in the preparation of natural explosions in the permafrost. With the ongoing economic development of the Arctic, thermal effects on permafrost increase, and so does the hazard of explosive processes for engineering structures. However, this group of processes is not taken into account when choosing design solutions and predicting the interaction of an engineering structure with permafrost soils; moreover, these processes are even not included in the group of hazardous geological processes.