Context
Permafrost covers 20-25% of the land surface in the Northern Hemisphere. Recent air temperature increase in the Arctic and Subarctic is significantly higher than the global average. Climate simulations predict continuing warming and increased wildfires occurrence. This rapid change is already leading to permafrost degradation, inducing ground subsidence and thermokarst, affecting land usability and stability of infrastructure. An increase in active layer thickness alters soil hydrology and groundwater drainage patterns.
Besides, large amounts of carbon and other inorganic elements, previously trapped in permafrost, are released towards aquatic systems. Microorganisms convert newly available highly biodegradable organic carbon into greenhouse gasses, amplifying global warming. As permafrost is known to contain vast amounts of frozen carbon, twice its current content in the atmosphere, its thawing poses a major risk because of the positive feedback on climate. Ultimately, climate change, through permafrost and habitat disturbance, affects local communities built on permafrost and threatens the traditional indigenous lifestyle. A better understanding of the impacts of permafrost thaw on soils, surface/groundwater fluxes (critical zone) and carbon cycle, as well as their controlling factors, will contribute to the understanding of permafrost-climate feedback.
Contributing to fill this knowledge gap, the overarching goal of the PRISMARCTYC project is to understand the different hydrogeomorphological and biogeochemical processes modifying permafrost soils, surface and groundwater runoff, driven by permafrost degradation in small watersheds.
This goal will be achieved by comparing different sites in Siberia, Canada and Alaska with different permafrost settings (e.g., ice-rich Yedoma permafrost or carbon-rich permafrost peatland; continuous or discontinuous permafrost), climate-sensitivity, vegetation, permafrost degradation types along a latitudinal and longitudinal gradient. The key study sites in Siberia and Canada have been chosen based on the expertise of the team members to cover a broad range of permafrost settings and degradation types, to allow cross-comparison. Central Yakutian lowlands (Eastern Siberia), Southwestern Yukon (Canada) and Chersky (North-Eastern Yakutia, Eastern Siberia) will be the main study areas where intensive fieldwork will be conducted. Olekma (Southern Yakutia, Eastern Siberia) and Batagay (Northern Yakutia, Eastern Siberia) will be the secondary study sites, where field research will be less detailed. Igarka (Western Siberia) and Alaska (transect from Denali Range to North Slope Toolik station) are selected as comparative sites as they were already studied by members of the project.
Work Package of the Project
A set of quantitative indicators (or ‘sentinels’) of the vulnerability of soils, surface- and groundwater is used to understand and cross-compare the impacts of permafrost degradation between the different sites. These indicators cover permafrost conditions, water chemistry, carbon cycle and microbial communities as major components of the permafrost-hydrosystem continuum. We analyze the differences and similarities between sites in terms of permafrost degradation, and develop and test numerous vulnerability/sustainability indexes for small watersheds encompassing different indicators.
The project is organized in several work packages (WPs) interacting with each other. Each WP focuses on a compartment and/or pathway of the near-surface permafrost-hydrosystem continuum:
WP1
Permafrost characteristics and degradation resulting from natural and anthropogenic disturbances
WP1 seeks to address critical knowledge gaps regarding the permafrost state, structure and loss rate.
T1.1: Analysis of spatio-temporal distribution of thermokarst subsidence after surface disturbances
T1.2: Identifying influence of surface disturbances on permafrost soil development
T1.3: Identifying key climatic and anthropogenic factors favoring thermokarst initiation
T1.4: Estimation of carbon stock in the vulnerable permafrost layer
Co-leaders: Go Iwahana (UAF), Aleksei Lupachev (IBPC)
Participants: T1.1: Masato Furuya, Kazuki Yanagiya (Hokkaido Univ.); T1.2: Go Iwahana (UAF); T1.3: Antoine Séjourné (GEOPS), François Costard (GEOPS); T1.4: Aleksei Lupachev (IBPC), Andrey Shepelev (Melnikov Perm Institute), Nic Jelinski (UM)
Permafrost characteristics and degradation resulting from natural and anthropogenic disturbances
WP2
Impact of permafrost thaw on groundwater and surface water composition. Transfers of particulate organic, dissolved inorganic and organic elements
WP2 seeks to understand how permafrost degradation affects groundwater and surface water pathways and the origin, composition and lability of organic matter released to surface and groundwater.
T2.1 Impact of permafrost thaw on surface and groundwater connectivity and soil erosion/weathering
T2.2 Origin and fate of organic matter released from thawing permafrost to aquatic ecosystems
T2.3 Seasonality of DOC and POC export/transfer in the context of thawing permafrost
Co-leaders: Nikita Tananaev (Melnikov Perm Institute), Laure Gandois (EcoLab)
Participants: T2.1: Christelle Marlin (GEOPS), Antoine Séjourné (GEOPS); T2.2: Laure Gandois (EcoLab), Nikita Tananaev (MPI), Frédéric Bouchard (GEOPS); T2.3: Nikita Tananaev (MPI), Laure Gandois (EcoLab), Roman Teisserenc (EcoLab)
Impact of permafrost thaw on groundwater and surface water composition
WP3
Characterization of microbial processes controlling the magnitude, speed and seasonal dynamics of greenhouse gas emissions from permafrost ecosystems
The main objective of WP3 is to better understand the microbial processes leading the production and mitigation of GHG and to relate MC structure and function with gas fluxes and C sources and ages.
T3.1 Stocks and fluxes of GHG in the active layer and shallow permafrost
T3.2 Production and emission of GHG from aquatic systems: physicochemical factors
T3.3 Characterization of microbial (bacteria and archaea) community structure and function
Co-leaders: Frédéric Bouchard (GEOPS), Maialen Barret (EcoLab)
Participants: T3.1: Maria Cherbunina (Moscow State Univ.), Liudmila Krivenok and Vladimir Kazantsev (IAP); T3.2: Frédéric Bouchard (GEOPS), Lea Cabrol (MIO-IRD), Frédéric Thalasso (University of Magallanes); T3.3: Maialen Barret (EcoLab), Urania Christaki (LOG), Kostantinos Kostantinidis (GATECH), Ludwig Jardillier (ESE)
Characterization of microbial processes and greenhouse gas emissions from ecosystems
WP4
Transversal WP: Indigenous community-based monitoring observatories of the evolution of permafrost environment
The objectives of WP4 are to document traditional knowledge on permafrost and to develop multidisciplinary community-based monitoring of permafrost.
T4.1 Document traditional knowledge on permafrost
T4.2 Address how indigenous communities perceive changes
T4.3 Develop multidisciplinary community-based monitoring of permafrost
Co-leaders: Alexandra Lavrillier (CEARC), Semen Gabyshev (Indigenous reindeer herder and co-researcher CEARC)
Participants: T4.1: Alexandra Lavrillier (CEARC), Semen Gabyshev (Indigenous reindeer herder); T4.2: Alexandra Lavrillier (CEARC), Semen Gabyshev (Indigenous reindeer herder), Nikita Tananaev (MPI), Dmitrieva Valentina (EYGE); T4.3: Alexandra Lavrillier (CEARC), Semen Gabyshev (Indigenous reindeer herder), Antoine Séjourné (GEOPS)
Transversal WP: Indigenous community-based monitoring observatories
WP5
Management, synthesis and comparisons
The objective of this WP is to carry out the daily management and funding of the project. This task will be in charge of the Management Group.
Co-leaders: Antoine Séjourné (GEOPS), Nikita Tananaev (MPI), Go Iwahana (UAF), Masato Furuya (Hokkaido Univ.)
Management, synthesis and comparisons
WP6
Communication and Education toward Arctic communities
The objectives of this WP is to support the teaching of climate changes in the Arctic and to develop outreach activities about the Arctic
T6.1 Education of climate change and permafrost degradation issues in the Arctic
T6.2 Outreach activities with children
T6.3 Communication toward local communities of the impacts of permafrost degradation
T6.4 Indigenous knowledge of the evolution of environment in Yakutia
Co-leaders: Lydie Lescarmontier (OCE), Antoine Séjourné (GEOPS)
Participants: T6.1: Lydie Lescarmontier et David Wilgenbus (OCE), Galina Burtseva (School, Syrdakh); T6.2: Antoine Séjourné (GEOPS), Frédéric Bouchard (GEOPS); T6.3: Nikita Tananaev (MPI), Dmitrieva Valentina (EYGE); T6.4: Alexandra Lavrillier (CEARC), Galina Burtseva (School, Syrdakh), Anna Andreeva (School, Bestyakh)
Communication and education toward Arctic communities
Expected outcomes of the PRISMARCTYC project and scientific impact
By linking the different Work Packages together, from field and remote sensing studies of permafrost to the hydrosystems, the project is likely to produce several outcomes:
- Identification of changes in the critical zone and water resources in small Arctic watersheds from the modifications on soils, carbon cycle and ground/surface waters due to permafrost degradation subsequent to natural and anthropogenic disturbances. Those knowledge gaps were identified as priority in the last Intergovernmental Panel on Climate Change (IPCC) Special Report on the Ocean and Cryosphere in a Changing Climate (processes associated with release of carbon (greenhouse gases and dissolved carbon) and impact of widespread wildfires on permafrost-supported ecosystems)
- Co-construction of two indigenous (Evenk and Sakha) community-based environmental observatories stemming from indigenous and scientific knowledge on permafrost evolution resulting in a new monitoring protocol
- Improved communication toward local communities with support from citizen-based associations of the current and future modifications of soil and water resources due to permafrost degradation
- Production of a handbook for teachers in several languages to support education of climate changes and permafrost at school as developing outreach scientific activities toward children
- Gathering of a strong international multidisciplinary consortium able to fully understand a complex system under natural and anthropogenic disturbances