Hot spot

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he Arctic is often described as the first “hot spot” of climate change, as it is warming significantly faster than lower-latitude regions. The terrestrial cryosphere—including continental glaciers, permafrost, and snow cover—along with sea ice, is shrinking at an alarming rate. These melting processes are driving widespread changes, including infrastructure instability, shifts in the hydrological cycle and albedo,1 alterations in soil structure and composition, and disruptions to ecosystems. The impact is especially pronounced on water and carbon fluxes between soil, vegetation, the ocean, and the atmosphere, potentially triggering feedback mechanisms that could accelerate both regional and global warming. 

 

The Aldo Pontremoli Center 

To investigate these issues, Eni and the Italian National Research Council (CNR) established Italy’s first integrated research center for the study of the Arctic terrestrial cryosphere in 2019. The center is dedicated to Aldo Pontremoli, a renowned scientist who perished during the ill-fated Dirigibile Italia mission. Pontremoli was a strong advocate for Arctic scientific research, playing a key role in the exploration campaigns led by Amundsen and Nobile. The Pontremoli Center focuses on studying and quantifying the climate and environmental feedbacks triggered by the thermal destabilization of the Arctic terrestrial cryosphere, particularly permafrost.2 These feedback mechanisms have the potential to accelerate global warming and reshape the Arctic environment. While their impact is clear, the rate of change and its broader effects remain uncertain. This is largely due to the challenges of accessing remote Arctic regions, which limit the collection of field measurements and hinder precise forecasting. 

To ensure a holistic and integrated approach, the Pontremoli Center conducts research across three key areas: 

1. The impact of atmospheric emissions on the cryosphere 

2. The effects of permafrost thawing on the Arctic Ocean 

3. The impact of permafrost degradation on terrestrial ecosystems 

These research lines aim to deepen our understanding of how Arctic changes influence both regional and global climate dynamics. 

 

 

 

The impact of climate-changing emissions on the cryosphere

Research Line I focuses on atmospheric processes and their effects on the Earth’s cryosphere, particularly in relation to climate change. One area of investigation includes phenomena that were once rare at high latitudes but have now become more frequent, such as rain-on-snow events, where precipitation occurs while the ground is still covered in snow. However, much of the research has concentrated on analyzing the composition of the lower atmosphere, with a specific focus on greenhouse gases and aerosols, the primary agents of climate change. Among greenhouse gases, the project has examined carbon dioxide and methane, studying their fluxes—both emission and uptake—between tundra and atmosphere in the Svalbard Islands. This research, conducted in collaboration with Project Line III, considers the distinct meteorological and seasonal patterns of Arctic environments. 

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ne of the study’s unexpected findings revealed that, during the summer months, not only carbon dioxide but also methane was absorbed in the dry tundra of Svalbard, a landscape characterized by nutrient-poor soils. This suggests that in addition to vegetation, methanotrophic bacteria—microorganisms that consume methane —play a significant role in the Arctic carbon cycle. The project also examined tropospheric ozone using a high-resolution chemical transport model (CTM), powered by high-performance computing (HPC) infrastructure provided by Eni. This approach allowed for detailed simulations of ozone chemistry, taking into account air mass transport and seasonal variations in Arctic light cycles, which shift dramatically between winter and summer. 

Another major area of research has focused on the role of atmospheric aerosols in the Arctic cryosphere, a particularly complex issue due to the extreme variability of their sources—both natural and anthropogenic—and their diverse chemical properties. Aerosols interact with solar radiation, influence cloud formation, and can be deposited on snow cover, altering its physical properties while also carrying pollutants and contaminants. To better understand these processes, snow deposition has been studied in two contrasting Arctic environments: a coastal fjord site in the Svalbard Islands, home to the Dirigibile Italia Station, and a site near Fairbanks, Alaska, in the interior Arctic region. Observations from both locations revealed that, despite the stabilizing effect of a cold surface on atmospheric layers, wind-driven turbulence plays a key role in transporting aerosol particles to the snow surface. The porous structure of the snowpack acts like a sponge, absorbing aerosols more than previously predicted by analytical models, which tend to assume a perfectly smooth snow surface. This leads to a higher-than-expected accumulation of atmospheric particulate matter, highlighting the significant role of dry deposition in surface snow composition. 

Snowpack sampling also demonstrated that its actual composition is influenced by physical changes such as partial melting events, which cause chemical compounds and contaminants to migrate through the snowpack’s layers. In cases of extreme weather—such as intense winter rainfall that activates the hydrographic network—partial melting and runoff can lead to the early and rapid release of nutrients into fjords, with potential ecological consequences. A final measurement campaign, conducted in 2024 at Oliktok Point near Eni’s infrastructure in northern Alaska, will further expand this research by studying atmosphere-surface fluxes of climate-altering compounds and pollutants in yet another Arctic environment: the polygonal tundra wetlands overlooking the Arctic Ocean. 

 

Ocean-land interactions 

Research Line II focuses on the interactions between the ocean and land, with two main areas of investigation. The first examines the impact of rising Atlantic waters in the Arctic, a process driven by the retreat of sea ice and known as the Atlantification of the Arctic Ocean. This phenomenon accelerates the melting of the Earth’s cryosphere, contributing to shrinking glaciers and thawing permafrost. To study these changes, the research team monitored water column properties in northern Svalbard through a permanent marine observatory, strengthening the CNR’s observational network in Kongsfjorden along the Fram Strait, a critical passage for the North Atlantic Current. The high-resolution data collected was supplemented with sediment core analysis, which serves as a natural environmental archive. These archives allow researchers to extend observations back in time, filling gaps left by the absence of instrumental measurements in earlier decades. 

 

 

 

Findings indicate that the progressive reduction of sea ice, which initially began due to natural climate dynamics in the early 20th century, has been overtaken by a rapid acceleration linked to Arctic amplification and intensified warming at high latitudes. 

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nother research line, spanning the Fram Strait, the Siberian margin, and Alaska, examines how the loss of sea ice and tundra warming influence permafrost reactivation. This process has major implications for the release of greenhouse gases and the acidification of the ocean. By analyzing chemical signatures in sediments, researchers assessed how much carbon release originates from coastal erosion versus river transport, both of which are linked to Arctic permafrost destabilization. Their findings reveal contrasting regional trends. In Svalbard, a process known as "greening" is taking place, where retreating snow and glaciers enable the growth of young plant biomass. This phenomenon could act as a negative climate feedback, as the new vegetation helps capture atmospheric CO2. 

In contrast, regions such as Siberia and Alaska are releasing organic material that has been frozen in permafrost for thousands of years. Once this material enters the carbon cycle, it can easily be converted into greenhouse gases, including carbon dioxide and methane, amplifying climate change through a positive feedback loop. 

 

Melting of the cryosphere and response of the ecosystems  

Whether rising Arctic temperatures lead to CO2 capture or release—and thus trigger a negative or positive climate feedback—depends on how climatic and environmental factors influence photosynthesis and cellular respiration. Research Line III investigates this balance, as it remains unclear which of these processes will dominate and how other variables contribute to their spatial and temporal variability. It is well established that solar radiation intensity is the main driver of photosynthesis, while temperature regulates respiration. However, tundra ecosystems present unique challenges. Their growing season is extremely short but intense—within just a few weeks, plants must complete their entire life cycle, including growth, flowering, pollination, seed dispersal, or vegetative expansion. This rapid summer growth occurs within a narrow window when the ground is snow-free, radiation is relatively strong, and temperatures rise above freezing. The Arctic tundra supports a variety of vascular and nonvascular plants, including mosses and lichens, which form extensive networks of “biocrusts” that contribute to photosynthetic activity. The distribution of these plant communities is shaped by geomorphological factors, such as the age of soil formation, which depends on the timing of glacial retreat. Some soils have existed for thousands of years, while others are only decades or even years old, particularly in areas near retreating glaciers. 

At the same time, vegetation and soil microorganisms respire, breaking down and consuming organic matter. Different plant species exhibit varying levels of biological activity, affecting both soil moisture and temperature, which in turn influence CO2 fluxes. To quantify these dynamics, researchers conduct point-scale measurements of photosynthetic capacity (“primary productivity”) and respiration across large areas and over extended periods. 

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hese measurements are taken using an Infrared Gas Analyzer, a portable CO2 concentration sensor. Combined with an accumulation chamber placed on the soil, this setup allows scientists to track CO2 fluxes between the soil, vegetation, and atmosphere. Each summer, extensive field campaigns gather primary productivity and ecosystem respiration data, which are then used to build mathematical models that quantify how various environmental factors influence Arctic CO2 exchange. Empirical models, derived through statistical analysis, indicate that besides solar radiation and temperature, two key factors determine CO2 flux: the degree of vegetation cover (“Green Fractional Cover”) and the time elapsed since snowmelt. Both serve as indicators of vegetation growth (phenology) and highlight the seasonal dependence of photosynthesis and respiration. Additional factors, such as soil moisture and temperature, drive spatial variability but become less significant when analyzing long-term seasonal trends. Accurately measuring high-resolution CO2 fluxes between the tundra and the atmosphere is crucial for improving large-scale climate models. These refinements help predict whether rising Arctic temperatures will cause the tundra to permanently shift from a carbon sink to a net CO2 source. Arctic soils have long helped mitigate rising atmospheric CO2 levels, slowing climate change. Understanding whether this function will persist or reverse is critical—if the tundra becomes a net emitter of CO2, it could further accelerate global warming. Over more than five years of operation, the Aldo Pontremoli Center has systematically examined and quantified climate and environmental feedbacks linked to the thermal destabilization of the Arctic terrestrial cryosphere, particularly permafrost. Its research has helped reduce uncertainties about the potential role of Arctic soils in a warming climate. Beyond advancing scientific understanding, the center has also expanded access to Arctic research sites and established permanent monitoring infrastructure, including several one-of-a-kind facilities. These resources enable the long-term observation and quantification of climate change effects in one of the planet’s most critical hot spots.