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Plateau pikas, small mammals native to the Qinghai‐Tibet Plateau (QTP), create bare patches through burrowing. No previous assessment exists on their impact on permafrost. This study fills this gap by simulating hypothetical scenarios in the Three Rivers Headwaters Region of the QTP using the Noah‐MP model for the plant growing seasons during 2015–2018. Our findings reveal a significant increase in soil temperature in the active layer due to pika‐induced bare patches, particularly during July–August. The average temperature rise at 2.5 cm depth was 0.36°C in permafrost regions and 0.29°C in seasonally frozen ground regions during August. Minimal impact on unfrozen water content was observed, with a slight increase in deep soil layers in permafrost regions, and negligible in seasonally frozen areas. These findings underscore the previously unexplored influence of pika burrowing on permafrost temperature, suggesting a potential risk of accelerating permafrost degradation, especially in permafrost‐dominated regions. Plain Language Summary On the vast Qinghai‐Tibet Plateau (QTP), plateau pikas are actively excavating burrows, creating bare patches of exposed earth within the typical grassland landscape. These seemingly minor disturbances can have significant consequences, as they alter heat and water conditions within the underlying permafrost. However, a comprehensive understanding of how these pika‐made patches impact the permafrost remains elusive. To address this gap, our study employed a computer model and simulating scenarios with and without pika patches in the ecologically fragile Three Rivers Headwaters Region (TRHR) of the QTP. We found that the pika‐induced bare patches significantly raised permafrost temperatures, especially in the shallow soil layers. During August, the peak pika activity month, the average soil temperature at a depth of 2.5 cm increased by 0.36°C in permafrost zones and 0.29°C in seasonally frozen ground zones. While the patches had minimal impact on unfrozen water content in the active layer, the temperature rise in permafrost warrants future concern. Key Points Bare patches due to plateau pika burrowing warmed permafrost, particularly during peak activity months and in shallow soil layers Pika bare patches warmed permafrost and seasonally frozen ground by about 0.36°C–0.29°C, respectively, at a 2.5 cm depth in August Pika‐induced bare patches had negligible impact on the unfrozen water content in the active layer of permafrost

The Qinghai–Tibet Plateau (QTP) is characterized by its extreme climate and dominated by periglacial processes. Permafrost conditions vary greatly, and the recent changes on the QTP are not well known in the hinterland. Here, we examine the changes in climate and permafrost temperatures in several different regions. Climate data were obtained from three weather stations from 1957 to 2019. Annual mean air temperature (T a ) has gradually increased at .031°C/yr–.039°C/yr. Climate warming has been more rapid in the past two decades, particularly during the cold season (November to February). Precipitation has also been slowly increasing during the instrumental record. However, there is pronounced heterogeneity in the seasonal distribution of precipitation, with very little falling between October and April. Ground temperatures and active-layer thickness (ALT) have been investigated over ∼20 years at five sites representative of the hinterland of the QTP. These sites are located along the Qinghai–Tibet Highway, which crosses the permafrost zone and traverses the mountainous area and basin areas. Annual mean ground temperatures within the active layer (T al ∼ 1 m depth) indicate recent ground warming at all sites, at rates near .05°C/yr. The ALT at five sites has been increasing steadily by 2–9 cm/yr, with an average of 4.6 cm/yr. The temperature near the permafrost table (T ps ) has been increasing at .01°C/yr and .06°C/yr, with an average of .03°C/yr. Permafrost temperatures at 15 m depth (T g ) have been increasing by about .01°C/yr–.02°C/yr. The southern boundary (AD site) of the permafrost has warmed the least among the five locations. In high mountainous areas where permafrost temperatures are low (e.g., KLS site), the annual mean T g has increased by nearly .02°C/yr. The rate of permafrost warming at a basin site (BLH), with relatively high ground temperatures, was approximately .01°C/yr. The GIPL2.0 model simulation results indicate that the annual mean permafrost temperature at 1 m depth at these sites will increase by .6°C–1.8°C in the next 100 years (to 2100) and that ALT will increase by ∼40–100 cm. We also discuss the impacts of permafrost changes on the environment and infrastructure on the QTP. This study provides useful information to understand observed and anticipated permafrost changes in this region, under different shared socioeconomic pathways, which will allow engineers to develop adaptation measures.

Exploring one of the greatest potential contributors to climate change-thawing permafrost-and the anxiety of extinction on an increasingly hostile planet Climate scientists point to permafrost as a \"ticking time bomb\" for the planet, and from the Arctic, apocalyptic narratives proliferate on the devastating effects permafrost thaw poses to human survival. In Earth, Ice, Bone, Blood , Charlotte Wrigley considers how permafrost-and its disappearance-redefines extinction to be a lack of continuity, both material and social, and something that affects not only life on earth but nonlife, too. Earth, Ice, Bone, Blood approaches the topic of thawing permafrost and the wild new economies and mitigation strategies forming in the far north through a study of the Sakha Republic, Russia's largest region, and its capital city Yakutsk, which is the coldest city in the world and built on permafrost. Wrigley examines people who are creating commerce out of thawing permafrost, including scientists wishing to recreate the prehistoric \"Mammoth steppe\" ecosystem by eventually rewilding resurrected woolly mammoths, Indigenous people who forage the tundra for exposed mammoth bodies to sell their tusks, and government officials hoping to keep their city standing as the ground collapses under it. Warming begets thawing begets economic activity- and as a result, permafrost becomes discontinuous, both as land and as a social category, in ways that have implications for the entire planet. Discontinuity, Wrigley shows, eventually evolves into extinction. Offering a new way of defining extinction through the concept of \"discontinuity,\" Earth, Ice, Bone, Blood presents a meditative and story-focused engagement with permafrost as more than just frozen ground.

The permafrost along the China-Russia Crude Oil Pipeline (CRCOP) is degrading since the pipeline operation in 2011. Heat dissipated from the pipeline, climate warming and anthropogenic activities leads to permafrost warming. The processes of permafrost warming along the CRCOP were studied based on the monitoring of air and soil temperatures, and electrical resistivity tomography (ERT) surveys. Results show that: (1) the mean annual air temperature (MAAT) in permafrost regions along the CRCOP increased with a rate of 0.21°C/10a–0.40°C/10a during the past five decades; (2) the mean annual ground temperature (MAGT, at −15 m depth) of undisturbed permafrost increased by 0.2°C and the natural permafrost table remained unchanged due to the zero-curtain effect; (3) permafrost surrounding the uninsulated pipeline right-of-way warmed significantly compared with that in a natural site. During 2012–2017, the MAGT and the artificial permafrost table, 2 m away from the pipeline centerline, increased at rates of 0.063°C/a and 1.0 m/a. The thaw bulb developed around the pipe and exhibits a faster lateral expansion; (4) 80- mm-thick insulation could reduce the heat exchange between the pipeline and underlying permafrost and then keep the permafrost and pipe stable. The MAGT and the artificial permafrost table, 4.8 m away from the center line of the pipeline, increased by 0.3°C/a and 0.43 m/a, respectively. Due to the heat disturbance caused by warm oil, the degradation of wetland, controlled burn each autumn and climate warming, the permafrost extent reduced and warmed significantly along the CRCOP route. Field observations provide basic data to clarify the interactions between CRCOP and permafrost degradation and environmental effects in the context of climate change.

Permafrost in Northeastern China is not only controlled by latitude and elevation, but also locally environmental factors, such as vegetation cover and human activities. During 2009–2022, thinning active layer, increasing annual maximum frost depth in talik zones and lowering ground temperature above the depth of dividing point (DDP) between permafrost cooling and warming have been observed in many places, possibly due to the global warming hiatus (GWH). However, the responses of permafrost below DDP did not show a clear trend to the GWH, despite an evident ground warming. The warming and degradation of permafrost below DDP in the Da Xing’anling Mountains are more strongly influenced by the overall climate warming than by regional GWH. This study improves our understanding of changing permafrost temperature and its drivers. It also helps to provide data support and references for the management of the ecological and hydrological environment of the northern Da Xing’anling Mountains and the Heilongjiang-Amur River Basin.

This paper investigates the stability of the earthen roadbed built in the warm and ice-rich permafrost region. The varying thermal regime of the subgrade and the ongoing settlement of the roadbed were observed at field. The temperature data demonstrate that in warm and ice-rich permafrost regions, adoption of earthen roadbed results in warming of the underlying permafrost. It is primarily because the earthen roadbed traps the warm-season absorbed heat in the natural ground. In addition, the carried heat of the earthen roadbed that was constructed in warm season propagates downward to warm the underlying soil. The warming permafrost layer promotes the roadbed settlement, which was mostly linearly developed in the past five service years. A comprehensive analysis for the varying thermal regime and the ongoing settlement shows that the unfrozen water liberated from the warming, undrained layer experiences consolidation. The deformation of the undrained soils is mainly responsible for settlement of the roadbed. In comparison, the temperature variation of this warming permafrost layer is found to be less beneath roadbeds protected by thermosyphons or crushed rock revetments. The installation of thermosyphons into the earthen roadbed is recommended to prevent the further degradation of the underlying permafrost.

The objectives were (i) to evaluate the relationship between recent climate change and extreme hydrological events and (ii) to characterize the behavior of hydrological events along the Alazeya River. The warming rate of air temperature observed at the meteorological station in Chersky was 0.0472 °C·year−1, and an extraordinary increase in air temperatures was observed in 2007. However, data from meteorological stations are somewhat limited in sparsely populated regions. Therefore, this study employed historical remote sensing data for supplementary information. The time-series analysis of the area-averaged Global Precipitation Climatology Project (GPCP) precipitation showed a positive trend because warming leads to an increase in the water vapor content in the atmosphere. In particular, heavy precipitation of 459 ± 113 mm was observed in 2006. On the other hand, the second-highest summer National Oceanic and Atmospheric Administration (NOAA) Advanced Very High Resolution radiometer (AVHRR) brightness temperature (BT) was observed in 2007 when the highest air temperature was observed in Chersky, and the anomaly from normal revealed that the summer AVHRR BTs showed mostly positive values. Conversely, riverbank, lakeshore and seashore areas were much cooler due to the formation, expansion and drainage of lakes and/or the increase in water level by heavy precipitation and melting of frozen ground. The large lake drainage resulted in a flood. Although the flooding was triggered by the thermal erosion along the riverbanks and lakeshores—itself induced by the heat wave in 2007—the increase in soil water content due to the heavy precipitation in 2006 appeared to contribute the magnitude of flood. The flood was characterized by the low streamflow velocity because the Kolyma Lowlands had a very gentle gradient. Therefore, the flood continued for a long time over large areas. Information based on remote sensing data gave basic insights for understanding the mechanism and behavior of climate-induced extreme hydrologic events.

This chapter contains sections titled: Introduction Lessons from the Past Freezing, Thawing and Bedrock Instability Warming Permafrost Changes in Azonal Processes Geotechnical Implications of Warming Permafrost Conclusions References Discussion Questions Some Useful Internet Sources

Northern peatlands have accumulated large stocks of organic carbon (C) and nitrogen (N), but their spatial distribution and vulnerability to climate warming remain uncertain. Here, we used machine-learning techniques with extensive peat core data (n > 7,000) to create observation-based maps of northern peatland C and N stocks, and to assess their response to warming and permafrost thaw. We estimate that northern peatlands cover 3.7 ± 0.5 million km² and store 415 ± 150 Pg C and 10 ± 7 Pg N. Nearly half of the peatland area and peat C stocks are permafrost affected. Using modeled global warming stabilization scenarios (from 1.5 to 6 °C warming), we project that the current sink of atmospheric C (0.10 ± 0.02 Pg C·y−1) in northern peatlands will shift to a C source as 0.8 to 1.9 million km² of permafrost-affected peatlands thaw. The projected thaw would cause peatland greenhouse gas emissions equal to ∼1% of anthropogenic radiative forcing in this century. The main forcing is from methane emissions (0.7 to 3 Pg cumulative CH4-C) with smaller carbon dioxide forcing (1 to 2 Pg CO2-C) and minor nitrous oxide losses. We project that initial CO2-C losses reverse after ∼200 y, as warming strengthens peatland C-sinks. We project substantial, but highly uncertain, additional losses of peat into fluvial systems of 10 to 30 Pg C and 0.4 to 0.9 Pg N. The combined gaseous and fluvial peatland C loss estimated here adds 30 to 50% onto previous estimates of permafrost-thaw C losses, with southern permafrost regions being the most vulnerable.

As global temperatures rise, large amounts of carbon sequestered in permafrost are becoming available for microbial degradation. Accurate prediction of carbon gas emissions from thawing permafrost is limited by our understanding of these microbial communities. Here we use metagenomic sequencing of 214 samples from a permafrost thaw gradient to recover 1,529 metagenome-assembled genomes, including many from phyla with poor genomic representation. These genomes reflect the diversity of this complex ecosystem, with genus-level representatives for more than sixty per cent of the community. Meta-omic analysis revealed key populations involved in the degradation of organic matter, including bacteria whose genomes encode a previously undescribed fungal pathway for xylose degradation. Microbial and geochemical data highlight lineages that correlate with the production of greenhouse gases and indicate novel syntrophic relationships. Our findings link changing biogeochemistry to specific microbial lineages involved in carbon processing, and provide key information for predicting the effects of climate change on permafrost systems. Analysis of more than 1,500 microbial genomes sheds light on the processing of carbon released as permafrost thaws.