Hanne H. Christiansen

• PhD
• Professor (Full) at University Centre in Svalbard

Mountain permafrost, constituting 30% of the global permafrost area, is sensitive to climate change and strongly impacts mountain ecosystems and communities. This study examines 21st century permafrost warming in European mountains using decadal ground temperature data from sixty-four boreholes in the Alps, Scandinavia, Iceland, Sierra Nevada and S...

Interferometric Synthetic Aperture Radar (InSAR) remote sensing of surface displacement in permafrost environments has the potential to resolve ground ice dynamics and potentially active layer thickness, yet field validation is sparse. Here we present a comparison between in-situ ground ice contents and the seasonal InSAR displacements of the follo...

We perform a first permafrost higher education curriculum survey in Norden. Permafrost is part of the education within both bio- and geosciences and engineering, and the variation in educational activities reflect this. Five permafrost-specific geoscience and engineering permafrost courses exist, whereas there are 23 bachelor and 25 master courses...

Arctic observations in 2023 provided clear evidence of rapid and pronounced climate and environmental change, shaped by past and ongoing human activities that release greenhouse gases into the atmosphere and push the broader Earth system into uncharted territory. This chapter provides a snapshot of 2023 and summarizes decades-long trends observed a...

Rapid warming due to human-caused climate change is reshaping the Arctic, enhanced by physical processes that cause the Arctic to warm more quickly than the global average, collectively called Arctic amplification. Observations over the past 40+ years show a transition to a wetter Arctic, with seasonal shifts and widespread disturbances influencing...

Arctic wetlands are a globally significant store of soil organic carbon. They are often characterized by ice‐wedge polygons, which are diagnostic of lowland permafrost, and which greatly influence wetland hydrology and biogeochemistry during summer. The degradation of ice‐wedge polygons, which can occur in response to climate change or local distur...

Svalbard is a High Arctic Archipelago at 74-81 • N and 15-35 • E under the sovereignty of Norway. All settlements in Svalbard, including the capital of Longyearbyen (population 2400), currently have isolated energy systems with coal or diesel as the main energy source. Geothermal energy is considered as a possible alternative for electricity produc...

Rock glaciers are landforms related to permafrost creep that are sensitive to climate variability and change. Their spatial distribution and kinematic behaviour can be critical for managing water resources and geohazards in periglacial areas. Rock glaciers have been inventoried for decades worldwide, often without assessment of their kinematics. Th...

The dependence of rock glaciers on permafrost and thus their sensitivity to climatic parameters makes the spatial distribution of these landforms very important for hydrological and climate changes reasons. Inventories of rock glaciers have been produced for decades worldwide, often without an assessment of their kinematics; the availability of rem...

The carbon balance of high-latitude terrestrial ecosystems plays an essential role in the atmospheric concentration of trace gases, including carbon dioxide (CO2) and methane (CH4). Increasing atmospheric methane levels have contributed to ∼ 20 % of the observed global warming since the pre-industrial era. Rising temperatures in the Arctic are expe...

Svalbard is an area with high geothermal potential. The geothermal gradient (i.e. the temperature increase with depth) varies regionally but is generally high compared to e.g. mainland Norway. Below Longyearbyen, temperature rises with up to 45 °C/km. From 2013-2016, Longyearbyen-based company Store Norske led a RCN-financed pilot study which mappe...

In permafrost areas, the active layer undergoes seasonal frost heave and thaw subsidence caused by ice formation and melting. The amplitude and timing of the ground displacement cycles depend on the climatic and ground conditions. Here we used Sentinel-1 Synthetic Aperture Radar Interferometry (InSAR) to document the seasonal displacement progressi...

The carbon balance of high-latitude terrestrial ecosystems plays an essential role in the atmospheric concentration of trace gases, including carbon dioxide (CO2) and methane (CH4). Increasing levels of atmospheric methane have contributed to ~20 % of the observed global warming since the pre-industrial era. Rising temperatures in the Arctic are ex...

Large parts of the terrestrial area of planet Earth belong to the cryosphere. Its distribution is mainly governed by temperature, precipitation, and wind. Hence, snow and ice are predominant in high latitudes but are restricted to high altitudes in mid- and low latitudes. Here, we first give an overview of the physiography of mountains, cold lowlan...

Cold glacier beds, i.e., where the ice is frozen to its base, are widespread in polar regions. Common theories state that stable permafrost should exist under glacier beds on shorter timescales, varying from years to decades. Presently, only a few direct measurements of both subglacial permafrost and the processes influencing its thermal regime exi...

Methane release from beneath lowland permafrost represents an important uncertainty in the Arctic greenhouse gas budget. Our current knowledge is arguably best developed in settings where permafrost is being inundated by rising sea level, which means much of the methane is oxidised in the water column before it reaches the atmosphere. Here we provi...

Active layer probing in northern Sweden, northeast Greenland, and central Svalbard indicates active layer thickening has occurred at Circumpolar Active Layer Monitoring (CALM) sites with long‐term, continuous observations, since the sites were established at these locations in 1978, 1996, and 2000, respectively. The study areas exhibit a reverse la...

Cold glacier beds, i.e. where the ice is frozen to its base, are widespread in polar regions. Common theories state that stable permafrost should exist under glacier beds on shorter time scales, varying from years to decades. Presently, only a few direct measurements of both subglacial permafrost and the processes influencing its thermal regime exi...

Abstract. Methane release from beneath lowland permafrost represents an important uncertainty in the Arctic greenhouse gas budget. Our current knowledge is arguably best-developed in settings where permafrost is being inundated by rising sea level, which means much of the methane is oxidised in the water column before it reaches the atmosphere. Her...

This report follows up on the report published in the SESS Report 2018 (Christiansen et al. 2019). Since 2018, the Norwegian Environment Agency has released the Climate in Svalbard 2100 report summarizing observed trends in permafrost conditions over the period of field measurements and a forecast for the future, based on recent climate and permafr...

Nordenskiöld Land in Central Spitsbergen, Svalbard is characterized as a high latitude, high relief periglacial landscape with permafrost occurring both in mountains and lowlands. Freezing and thawing of the active layer causes seasonal frost heave and thaw subsidence, while permafrost-related mass-wasting processes induce downslope ground displace...

Permafrost is a key element of the cryosphere and an essential climate variable in the Global Climate Observing System. There is no remote-sensing method available to reliably monitor the permafrost thermal state. To estimate permafrost distribution at a hemispheric scale, we employ an equilibrium state model for the temperature at the top of the p...

Terrestrial Arctic ecosystems play a key role in the global carbon (C) cycle, as they store a large amount of organic matter in permafrost. Among regions with continuous permafrost, Svalbard has one of the warmest permafrost and may provide a template of the environmental responses of Arctic regions to future climate change. We analyze the CO2 flux...

The processes associated with the release of CH4 and CO2 from sub-permafrost groundwaters are considered through a year-long monitoring investigation at a terrestrial seepage site in West Spitsbergen. The site is an open system pingo thought to be associated with the uplift of a former sea-floor pockmark in response to marked isostatic recovery of...

Permafrost in circum‐polar regions has been recently undergoing thawing, with severe environmental consequences, including the release of greenhouse gases and amplification of global warming. Although highly important, there are no direct methods to track thawing. In a research study conducted at Adventdalen, Svalbard, we identified a permafrost ra...

This report was commissioned by the Norwegian Environment Agency in order to provide basic information for use in climate change adaptation in Svalbard. It includes descriptions of historical, as well as projections for the future climate development in the atmosphere, hydrosphere, cryosphere and ocean, and it includes effects on the physical natur...

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 Perma...

In 2017, the dominant greenhouse gases released into Earth's atmosphere-carbon dioxide, methane, and nitrous oxide-reached new record highs. The annual global average carbon dioxide concentration at Earth's surface for 2017 was 405.0 ± 0.1 ppm, 2.2 ppm greater than for 2016 and the highest in the modern atmospheric measurement record and in ice cor...

Twelve years of continuous monitoring of diverse ground properties reveals the dynamics of three ice wedges and adjacent ground in a low‐centered polygon area in Svalbard. The monitoring documented ground displacements, the timing of crack generation, ground thermal and moisture conditions from the surface to the top permafrost, and snow conditions...

Soils in the northern high latitudes are a key component in the global carbon cycle, with potential feedback on climate. This study aims to improve the previous soil organic carbon (SOC) and total nitrogen (TN) storage estimates for the Zackenberg area (NE Greenland) that were based on a land cover classification (LCC) approach, by using geomorphol...

Quantifying the unfrozen water content of permafrost is critical for assessing impacts of surface warming on the reactivation of groundwater flow and release of greenhouse gasses from degrading permafrost. Unfrozen water content was determined along a ~12 km transect in the Adventdalen valley in Svalbard, an area with continuous permafrost, using s...

Quantifying the unfrozen water content of permafrost is critical for assessing impacts of surface warming on the reactivation of groundwater flow and release of greenhouse gasses from degrading permafrost. Unfrozen water content was determined along an ~12-km transect in the Adventdalen valley in Svalbard, an area with continuous permafrost, using...

The infilling history of the Adventdalen fjord‐valley in central Spitsbergen is reconstructed, with a focus on permafrost development, based on sedimentological and cryostratigraphic evidence from drilling cores. The techniques of optically stimulated luminescence and radiocarbon accelerator mass spectrometry dating were used to establish sediment...

Determining the exact timing of ice‐wedge cracking in permafrost is challenging. Five miniature accelerometers were installed near the ground surface in the trough of a primary ice wedge within a network of low‐centered polygons in Adventdalen, Svalbard, to test whether these instruments could be used to detect dynamics of thermal contraction crack...

The ability to continuously monitor the dynamic response of periglacial landforms in a climate change context is of increasing scientific interest. Satellite radar interferometry provides information on surface displacement that can be related to periglacial processes. Here we present a comparison of 2D surface displacement rates and geomorphologic...

This study aims to improve the previous soil organic carbon (SOC) and total nitrogen (TN) storage estimates for the Zackenberg area (NE Greenland) that were based on a land cover classification (LCC) approach, by using geomorphological upscaling. In addition, novel SOC estimates for deeper deposits (down to 300 cm depth) are presented. We hypothesi...

In High Arctic northern Greenland, future responses to climatic changes are poorly understood on a landscape scale. Here, we present a study of the geomorphology and cryostratigraphy in the Zackenberg Valley in NE Greenland (74°N) containing a geomorphological map and a simplified geocryological map, combined with analyses of 13 permafrost cores an...

Permafrost is vulnerable to rapid changes in climate, and increasing air temperatures have recently resulted in the increase of active layer thickness, thaw subsidence and warming of the underlying permafrost. Such changes have important implications for geotechnical properties and the stability of infrastructures in permafrost-affected areas. Many...

Editor’s note: For easy download the posted pdf of the State of the Climate for 2017 is a low-resolution file. A high-resolution copy of the report is available by clicking here. Please be patient as it may take a few minutes for the high-resolution file to download.

Ch 7. Regional Climates: f. Europe and the Middle East

The Zackenberg River delta is located in northeast Greenland (74∘30′ N, 20∘30′ E) at the outlet of the Zackenberg fjord valley. The fjord-valley fill consists of a series of terraced deltaic deposits (ca. 2 km2) formed during relative sea-level (RSL) fall. We investigated the deposits using sedimentological and cryostratigraphic techniques together...

The University Centre in Svalbard (UNIS) is a unique institution with a history that is closely related to Norwegian policy regarding Svalbard, and to clever development of a highly specialised Arctic university institution by all the Norwegian universities. In practical terms, Norwegian sovereignty on the archipelago as confirmed by the Treaty of...

High-resolution field data for the period 2000–2014 consisting of active layer and permafrost temperature, active layer soil moisture, and thaw depth progression from the UNISCALM research site in Adventdalen, Svalbard, is combined with a physically based coupled cryotic and hydrogeological model to investigate active layer dynamics. The site is a...

Methane (CH4) emissions from arctic tundra typically follow relations with soil temperature and water table depth, but these process-based descriptions can be difficult to apply to areas where no measurements exist. We formulated a description of the broader temporal flux pattern in the growing season based on two distinct CH4 source components fro...

In periglacial landscapes, snow dynamics and microtopography have profound implications of freeze-thaw conditions and thermal regime of the ground. We mapped periglacial landforms at Kapp Linné, central Svalbard, where we chose six widespread landforms (solifluction sheet, nivation hollow, palsa and peat in beach ridge depressions, raised marine be...

The Zackenberg Delta is located in Northeast Greenland (74°30'N, 20°30'E) at the outlet of the Zackenberg Valley. The deltaic fill at the mouth of the valley consists of a series of terraces (ca. 2 km²) formed during a fall in relative sea level. The modern Zackenberg River has incised through the paleo-deltaic deposits creating exposures (up to 22...

Measurements of the land-atmosphere exchange of the greenhouse gases methane (CH4) and carbon dioxide (CO2) in high Arctic tundra ecosystems are particularly difficult in the cold season, resulting in large uncertainty on flux magnitudes and their controlling factors during this long, frozen period. We conducted snowpack measurements of these gases...

A research-based understanding of permafrost distribution at a sufficient spatial resolution is important to meet the demands of science, education and society. We present a new permafrost map for Norway, Sweden and Finland that provides a more detailed and updated description of permafrost distribution in this area than previously available. We im...

This study examines soil physical and environmental conditions controlling patterned-ground variability on an alluvial fan in a continuous permafrost landscape, at Adventdalen, Svalbard. On-site monitoring of ground temperature, soil moisture and snow depth, laboratory analyses of soil physical properties and principal component analysis indicate t...

A review of recent progress in understanding the dynamics, internal structure and palaeoenvironmental potential of ice wedges and sand wedges is presented, based on literature published between 2008 and 2015. Ice wedges constitute the most ice-rich and widespread periglacial landform in permafrost lowlands. Thus, progress in understanding the proce...

Avalanche activity in snow climates dominated by direct-action avalanches is primarily controlled by the local and synoptic scale meteorological conditions just prior to and during winter storm events. Previous work on Svalbard characterized the region’s unique, direct-action snow climate as “High Arctic maritime” and demonstrated an association be...

High resolution field data for the period 2000–2014 consisting of active layer and permafrost temperature, active layer soil moisture, and thaw depth progression from the UNISCALM research site in Adventdalen, Svalbard, is combined with a physically-based coupled cryotic and hydrogeological model to investigate active layer dynamics. The site is a...

In the Arctic, the 2015 land surface temperature was 1.2°C above the 1981–2010 average, tying 2007 and 2011 for the highest annual temperature and representing a 2.8°C increase since the record began in 1900. Increasing temperatures have led to decreasing Arctic sea ice extent and thickness. On 25 February 2015, the lowest maximum sea ice extent in...

The geomorphic development of mixed-type coasts, which consist of bedrock cliffs overlain by unconsolidated sediment, is poorly known in the Arctic but important for addressing long-term coastal responses and potential socio-economic implications of climate change. At Vestpynten, Svalbard, ground temperatures, erosion rates and thermo-denudation pr...

Large parts of the terrestrial area of planet Earth belong to the cryosphere. The distribution is mainly governed by temperature, precipitation, and wind. Hence, snow and ice are predominant in high latitudes, but are restricted to high altitudes in mid-latitudes and low latitudes. Here, we first give an overview of the physiography of high mountai...

A methodology was tested for high-resolution mapping of vegetation and detailed geoecological patterns in the Arctic Tundra, based on aerial imagery from an unmanned aerial vehicle (visible wavelength – RGB, 6 cm pixel resolution) and from an aircraft (visible and near infrared, 20 cm pixel resolution). The scenes were fused at 10 and 20 cm to eval...

The transport of reactive iron (i.e. colloidal and dissolved) by a glacier-fed stream system draining a high relief periglacial landscape in the high Arctic archipelago of Svalbard is described. A negative, non-linear relationship between discharge and iron concentration is found, indicative of increased iron acquisition along baseflow pathways. Si...

ABSTRACT The Global Terrestrial Network for Permafrost (GTN-P, gtnp.org) established the new ‘dynamic’ GTN-P Database (gtnpdatabase.org), which targets the Essential Climate Variable (ECV) permafrost, described by the thermal state of permafrost (TSP) and active layer thickness (ALT). This paper outlines the requirements for assessing the GTN-P dat...

The Jettan rockslide is an active topmost part of a large instability in paragneiss along the fjord Storfjorden in Northern Norway. It has deep back fractures in the top part with sliding planes at 45-50 m depth. The sliding planes seem to be controlled largely by SW-NE trending regional faults dipping steeply downslope towards NW. The displacement...

Large parts of the terrestrial area of planet Earth belong to the cryosphere. The distribution is mainly governed by temperature, precipitation, and wind. Hence, snow and ice are predominant in high latitudes, but are restricted to high altitudes in mid-latitudes and low latitudes. Here, we first give an overview of the physiography of high mountai...

The map is accompanied by popular science text and photos explaining the main land-forms and processes on the map. The landscape story told on this map is the result of geology, geomorphology and climate driven processes in high arctic Svalbard. The map informs about the landscape we see today and also gives information about hazards and challenges...

This map illustrates land-forms and sediments in an small area along the central Svalbard coast. Additional text and photos explains in a popular science language the main land-form units ans the processes that have created them. Map is in scale1:10'000.

As part of the world’s needs for CO2-injection test sites, the city of Longyearbyen in Svalbard is an interesting location for testing technologies related to carbon capture and storage (CCS) in a vulnerable arctic environment, being a closed energy system with a coal-fuelled power plant. Therefore, the University Centre in Svalbard (UNIS) establis...

Knowledge about the detailed processes linked to the existence of permafrost in rockslide fractures is sparse. Large parts of the Jettan rockslide are located right below the discontinuous permafrost limit in the arctic part of the alpine landscape of northern Norway. Combining four years of meteorological and rockslide deformation data with temper...