OVERVIEW

Imagery analysis has identified indicators of environmental damage to Russian airfield infrastructure built on permafrost within the Arctic Circle, as well as indicators of repair activities required to maintain the functionality of the airfields. The annual increase in warming of the region compared to the global average will likely require significant investment in airfield infrastructure maintenance and new construction techniques. These techniques should be more resilient against the threat of permafrost thawing at an accelerated rate.

Russia must engage in regular upkeep of existing airfields and robust construction of new ones to take advantage of its strategic posture in the Arctic. This analysis has identified significant shortcomings towards this effort and a systemic level of impact across airfields in the Russian Arctic. This report provides a background on Russia's Arctic ambitions and a brief explanation of permafrost. It then follows an indicator-centric approach to identify permafrost, damages to infrastructure, and evidence of repairs. A target-centric application of these indicators is applied to a case study focused on Tiksi Airbase, and the report concludes with recommendations for future analysis related to these topics.

The table below lists the Russian Arctic airfields that were the focus of imagery analysis for this report, in descending order of latitude. The list was adapted from the National Geospatial-Intelligence Agency's 2017 Arctic Open Data Portal; known additions were included based on open-source research. The assessments made in the table are best judgments based on imagery analysis and open-source research and are based on the suitability of each airfield for fixed-wing operations. Airfields in bold are referenced explicitly in this report due to their illustrative examples of indicators of interest, but this report is not meant to be an exhaustive compilation of all indicators at all sites.

RUSSIA’S ARCTIC DILEMMA

The increased warming of the Arctic presents both an opportunity and a challenge for Russian strategic military and economic interests. Decreased sea ice extent in the Arctic is expected to make the Northern Sea Route (NSR) and the Transpolar Sea Route (TSR) commercially lucrative economic corridors for Russia¹, but the associated permafrost thaw creates challenges in the maintenance of existing airfields and the construction of new ones to support economic and military activities in the region. According to the European Space Agency, climate change could result in an Arctic Sea free from summer ice by 2050², allowing longer shipping seasons along the NSR and TSR. Although Russia has the advantage of owning 53% of the Arctic coastline³, it must predict and address the risks posed by thawing permafrost to capitalize on its position. The same rapid increase in average temperature that is making the NSR, and eventually the TSR, a more viable shipping route is also destabilizing the permafrost-rich ground on which infrastructure must be maintained for Russia to capitalize on its geographically advantageous position in the region. Figure 2 illustrates that Russian Arctic airfields are generally evenly distributed along the Arctic coast but with a heavier concentration in the West.

In 2008, Russian President Dmitri Medvedev adopted a policy that laid out the federation’s interests, objectives, and strategic priorities in the Arctic until 2020.

“… it is necessary to carry out a complex building up of competitive advantages of the Arctic zone of the Russian Federation with a view of strengthening positions of Russia in the Arctic, consolidation of international security, maintenance of the peace and stability in the Arctic region.”⁴

Statements in this policy regarding the bolstering of infrastructure against climate change do not explicitly mention thawing permafrost as the leading factor in this threat, but the language used implies that unstable ground is a primary concern that needs to be addressed for Russia to take advantage of its strategic positions in the Arctic.

“…forecast and estimation of consequences of global climatic changes occurring in the Arctic zone Russian Federations under the influence of natural and anthropogenous (sic) factors, in intermediate term and long-term prospect, including an increase of stability of objects of the infrastructure…”⁵

On 05 March 2020, Russian President Vladimir Putin adopted a continuation of Medvedev’s Arctic policy, “Foundations of the Russian Federation State Policy in the Arctic for the Period up to 2035”. Though the policy largely follows the format and content of previous Russian and Soviet Arctic policies, it does contain slightly stronger language regarding the importance of the NSR to Russia’s economic health and the threats posed to infrastructure by climate change. The policy states that the implementation of Russia’s strategic aims in the Arctic is in direct support of overarching national priorities:

“e) developing the Northern Sea Route as the Russian Federation’s competitive national transportation passage in the world market;”⁶

The word “permafrost” does not appear in this policy. Yet, there is a clear emphasis on the need to adapt or develop science and engineering solutions that are resilient against climate change.

“c) to increase research on natural hazards and man-made hazardous activities in the Arctic, and develop and implement modern methods and technologies for predicting these effects in a changing environment, as well as methods and technologies to reduce threats to human life;

d) to develop and implement practical engineering solutions to prevent damage to infrastructure components due to global climate change…”⁷

Russia’s adopted strategic plans for the Arctic are ambitious and a high priority for their near- and long-term focus, but official government policies only indirectly address the threat posed to these interests by thawing permafrost. Arguably the most notable and public disaster in the Russian Arctic that has been attributed to the degradation of infrastructure due to thawing permafrost is the 2020 Norilsk Nickel diesel tank leak. This disaster led President Putin to declare a state of emergency and to order inspections of other “particularly dangerous installations” in permafrost areas⁸. Investigators attributed the leak to a failure of the diesel storage tank’s supports due to thawing permafrost, but the Russian Investigative Committee ultimately charged the power plant’s director with negligence. Despite the apparent attempt by the Russian government to place blame on an individual’s actions or lack thereof, the Norilsk disaster is likely an indicator of a more systemic issue regarding infrastructure built on permafrost.

“There isn’t a single settlement in Russia’s Arctic where you wouldn’t find a destroyed or deformed building.”⁹
Alexey Maslakov, Moscow State University

Russian Arctic scientists and citizens are more direct when bringing attention to the serious problems that this threat has already uncovered. The town of Churapcha, a Siberian settlement in the Yakutia region, is one of the more glaring examples of airfield failure due to thawing permafrost. In the 1990s, Churapcha’s airfield, initially built in the era of Soviet expansion into Arctic territories¹⁰, was permanently closed as thawing and refreezing permafrost below its surface became too severe to maintain the integrity of the airfield’s surface. Today, there is little evidence that the airfield at Churapcha ever existed as seen in Figure 3. The former site is now a field of clearly visible ice wedge patterning, a familiar terrain in much of the Russian Arctic. According to Alexander Fyodorov, deputy director of the Melnikov Permafrost Institute of the Siberian Branch of the Russian Academy of Sciences, 72% of residents surveyed in the Yakutia region reported problems with the stability of their homes’ foundations¹¹, suggesting that the threat to infrastructure from thawing permafrost is widespread throughout the Russian Arctic.

PERMAFROST OVERVIEW

Basic understandings of permafrost’s definition, extent in the Russian Arctic, and visible signatures of its presence are necessary to observe its effects on infrastructure. The first scientific studies of “permanent frost” were published in the 1830s by the Royal Geographical Society of London following a study of the thickness of frozen ground in Yakutsk, Russia, but the word “permafrost” was not adopted until over a century later during the construction of the Alaska Highway¹². Today, permafrost is defined by the National Snow and Ice Data Center (NSIDC) as a:

“…layer of soil or rock, at some depth beneath the surface, in which the temperature has been continuously below 0°C for at least several years; it exists where summer heating fails to reach the base of the layer of frozen ground”¹³

This general definition over arches two subcategories of permafrost: continuous and discontinuous. As the name implies, an area with continuous permafrost contains uninterrupted permafrost coverage beneath the surface, whereas discontinuous permafrost signifies an area containing pockets of permafrost amongst areas with no permafrost¹⁴. The below map shows that nearly all Russian airfields within the Arctic Circle have been built atop permafrost to some extent.

As Arctic temperatures continue to increase, thawing the permafrost layer to deeper depths, formerly solid ground held together by ice will become a fluid mass with the potential to wreak havoc on infrastructure built on the surface. Since the 1960s, some Russian Arctic cities have already seen a decrease in the ground’s load-bearing capacity by more than 40%¹⁵. Despite the difficulty in assessing whether a specific site has been built on continuous or discontinuous permafrost from satellite imagery, several visible indicators of permafrost thaw can assist in determining the severity of local ground destabilization. Ice wedges and thermokarst features are two common indicators of permafrost presence most useful for imagery analysis.

Permafrost Indicators

Ice Wedges

NSIDC defines an ice wedge as a:

“narrow ice mass that is 3 to 4 meters (10 to 13 feet) wide at the ground surface, and extends as much as 10 meters (33 feet) down; a decrease in temperature during the winter leads to ice wedge cracks in the ground around ice wedges; during the summer, these cracks accumulate melt-water and sediment, forming pseudomorphs.”¹⁶

Figures 5 and 6 show the degradation of ice wedge patterning over time and a cross-section view of an ice wedge, respectively.

Although ice wedges exist below the surface, their presence can be easily detected in satellite imagery by the distinctive polygonal patterning created on the surface as seen in Figures 7 to 12. Ice wedges shrink year over year as the permafrost continues to warm, leaving meltwater and troughs in their place. This evolution is important regarding threats to nearby infrastructure because ice-wedge degradation changes the hydrology in the surrounding area; this results in increased runoff of surface water with the potential to erode and destabilize foundations of buildings and airfields, buckle roads and railways, and cause the failure of the support pilings of above-ground gas and oil pipelines¹⁷.

Thermokarst Features

Thermokarst features are another familiar sight on the landscape of the Russian Arctic. Thermokarst is defined by NSIDC as:

“the process by which characteristic landforms result from the thawing of ice-rich permafrost or the melting of massive ice.”¹⁸

The definition of thermokarst is broad, and the phenomenon can manifest itself in various ways but is most easily observed on satellite imagery when a depression forms that has collected water. The presence of thermokarst lakes, ponds, and smaller pockets of standing water suggests that large portions of permafrost in the area no longer remain completely frozen in consecutive seasons. Though melting ice wedges can play a part in thermokarst feature formation, their development typically involves large-scale thawing of permafrost as well. The thermokarst process can create a feedback loop wherein thermokarst feature formation is followed by an even more rapid ice melting and permafrost thawing in the area¹⁹. Figures 14 through 18 are illustrative of the varying visual indicators of thermokarst lakes and ponds.

While larger thermokarst features like lakes and ponds can be associated with natural processes, imagery analysis has identified a trend of smaller thermokarst feature development directly adjacent to human activities such as excavation, construction, and routine activities. These smaller thermokarst features resulting from human activity can be identified by their irregular shapes as compared to thermokarst lakes; often, their shapes follow airfield drainage lines, artificial embankments, and building footprints. Figures 19 through 24 demonstrate examples of thermokarst feature development adjacent to human activity.

Permafrost Indicators Conclusion

Ice wedges and thermokarst features are two visible indicators of thawing permafrost, but it should be noted that their direct effects on nearby infrastructure can be difficult to ascertain from imagery analysis alone. The temporal and spatial resolution of electro-optical satellite imagery products are adequate to track incremental changes to permafrost indicators from year-to-year or season to season, but as the thawing continues to increase rapidly, abrupt permafrost thaw events have the potential to impart significant damage to infrastructure in a short period of time depending on local conditions at a specific site²⁰. Despite the challenges of predicting location-specific permafrost impacts to infrastructure, imagery analysis has identified a trend of permafrost-related damage to airfields and their surrounding infrastructure within the Russian Arctic.

INDICATORS OF DAMAGE

A rudimentary explanation of Russian airfield construction, which today is an evolution of Soviet techniques, is helpful in understanding indicators of airfield damage and their implications. A unique aspect of Russian airfield construction in the Arctic is the use of pre-cast, pre-stressed concrete slabs, which are welded together in place after being leveled atop a foundation generally made of sand, gravel, and crushed concrete which serves to insulate the surface from unstable ground and is necessary to increase the load-bearing capacity of the slab surface above²¹. An example of concrete airfield slabs and the welding technique used to secure them is provided in Figure 25. The portability of prefabricated concrete slabs made off-site makes them advantageous for use in the harsh and remote Arctic terrain; airfield slabs can be transported from concrete factories by land, sea, or air in batches for new airfield construction and for repairs as required²².

Proper drainage design is another component of Russian Arctic airfield construction which comes with unique considerations given the challenging nature of building above permafrost; Russian building codes for aerodromes provide guidance for creating drainage structures based on the unique hydrological and climatic characteristics of a specific site but does not offer precise requirements beyond stating that it is “necessary to provide measures aimed at preventing the occurrence and activation (of) thermokarst, thermal erosion, thermal abrasion, heaving, frost cracking, solifluction, ice formation, and other cryogenic processes”²³. Imagery analysis has identified damage to drainage structures and the secondary effects of this damage on other features of airfields, likely due to changes in local hydrology and surface stability caused by thawing permafrost since initial construction. Figure 26 uses Rogachovo airfield to illustrate an overview of common Russian airfield construction components.

Damage to Russian Arctic airfields and their supporting infrastructures poses a direct threat to Russia’s ability to project power and capitalize on economic opportunities in the region. Airfield surfaces and foundations, drainage features, and supporting facilities like fuel storage depots are all critical to the safe and effective functioning of an airfield. These airfield features are also all at risk of damage due to the unstable ground created by thawing permafrost. Imagery analysis has identified several trends in each category of infrastructure that show damage to key components of a usable airfield.

Airfield Surfaces and Foundations

The unique construction characteristics of Russian Arctic airfields present an opportunity for imagery analysts to identify surface damage indicators in two main categories. First, satellite imagery can show both horizontal and vertical dispersion between adjacent slabs. A significant enough difference in the spacing or vertical disparity of adjacent slabs in key areas of the airfield surface can render the airfield unusable if allowed to reach critical levels. Second, the degradation of individual slabs can be observed in the form of crumbling and cracking patterns. Both indicators are prevalent in all Russian Arctic airfields that were originally built in the Soviet era.

Runway touchdown zones (TDZs) are the “…point at which an aircraft first makes contact with the landing surface…” and are susceptible to the greatest vertical forces and are common areas showing indicators of damage to the airfield surface²⁴. At Rogachovo Air Base, distinct discoloration between concrete slabs within the TDZ is visible in Figures 27 and 28 and seems to suggest some degradation in the integrity of the surface.

Similar indicators of airfield surface damage are evident on parking aprons; Rogachovo and Naryan Mar are two locations with strong visual indicators of such damage as seen in Figures 29 and 30. Areas showing damage to the apron surface are consistent with what would be expected from recurring increased temperatures proximate to jet exhaust; this indicator suggests subsidence due to thermokarst processes or direct damage to the structural integrity of slab welds. This evidence shows that thermal impacts, as well as direct mechanical forces, have the potential to degrade airfield surfaces.

Indicators of damage to airfield surfaces resulting from abandonment or failure to perform routine maintenance of concrete slabs are also evident and can serve as a baseline for environmental effects over time. Severomorsk-2 is one example with indicators of surface damage in the form of slab separation and vegetation growth. This site is a particularly good example of long-term damage indicators, as hexagonal slabs, which were likely used for original construction in the 1930s²⁵, are visible alongside more recent rectangular slab additions to the airfield surface and surrounding areas. Both the hexagonal and rectangular slabs show visible indicators of increased separation and vegetation growth between adjacent slabs. Severomorsk-2 is also unique in that a new section of the runway was paved onsite, rather than constructed with concrete slabs, between August and October of 2016; the paved sections of the airfield already show significant indicators of cracking and subsidence. Figures 31 through 39 show the prevalence of this type of damage at airfields across the Russian Arctic.

Supporting Infrastructure

Russian Arctic airfields possess varying levels of local infrastructure related to their effective operation. In general, more remote airfields located at higher latitudes operate with a minimum of supporting infrastructure, such as fuel storage and distribution, command and control facilities, and limited aircraft maintenance support. Airfields collocated with industrial activities, such as resource mining or natural gas extraction, often have more robust supporting infrastructures required to carry out such activities and to support a local population. Imagery analysis has identified permafrost-related damage to supporting infrastructure at Russian Arctic airfields, the most extreme examples of which have resulted in the complete abandonment of infrastructure built on affected tracts of land.

Anadyr Ugolny Airport, located in Russia’s Far East, is a prime example of the extent to which permafrost thaw can damage infrastructure beyond what is reasonable to repair or repurpose. The west side of Anadyr Ugolny airfield, originally built in the 1950s²⁶ as a strategic deployment base for long-range bombers, stands in stark contrast to the modern infrastructure which has been built on the east side of the airfield to support civil flights. The original airfield infrastructure and neighboring settlement, known as “Coal Mines²⁷”, show extensive indicators of damage due to thawing permafrost. User-provided commentary of the village on Wikimapia suggests that the area was officially ordered to be resettled in 2014, yet a handful of hearty residents remain²⁸. Figure 40 demonstrates the impact of permafrost on infrastructure at Anadyr Ugolny; critical infrastructure from the original airfield and settlement has largely been abandoned in favor of new construction atop ground with less visible indicators of permafrost presence.

Modern fuel storage facilities have been built at Anadyr Ugolny, but damage to the Soviet-era fuel storage facilities in the area paints a concerning picture for the potential future of any infrastructure built on thawing permafrost. Four Soviet-era fuel storage sites dispersed along the west side of the airfield all present significant indicators of damage induced by thawing permafrost and associated thermokarst processes. Although these fuel storage sites are no longer necessary for the operation of Anadyr Ugolny, the disaster at Norilsk should serve as a warning that similarly constructed infrastructure is at risk of causing serious environmental damage if any fuel remains in the tanks. Figures 41 to 44 show a concerning pattern of thermokarst related deterioration of fuel tanks at Anadyr Ugolny.

Damage to buildings at Anadyr Ugolny is extensive and at varying levels of severity. In general, buildings closer to obvious indicators of permafrost have fared worse over time. The former village known as “Coal Mine” is a mix of residential and industrial buildings, some of which are in complete ruin, and it presents numerous indicators of damage from thawing permafrost as seen in Figure 45.

Outside of the former village itself, abandoned Soviet-era military infrastructure has fared poorly over time in the face of encroaching thermokarst features. One such example is the former site of “Unit 60082”, an anti-air defense unit that operated in support of the airfield²⁹. Figure 46 is an approximation of the footprint of the former military facility based on the presence of human-caused thermokarst indicators combined with open-source research.

Despite the obvious and extensive damage to infrastructure at Anadyr Ugolny and many other Russian Arctic airfields, it can be difficult to ascribe the damage to permafrost thaw with satellite imagery analysis alone. Open-source, user-provided images of Anadyr Ugolny and other sites can help demonstrate the extent to which subsidence of the ground is detrimental to the structural integrity of critical infrastructure, including energy delivery, communication lines, and buildings. Figures 47 through 50 provide ground-level examples of thermokarst features that are also visible from satellite imagery.

Damage Indicators Conclusion

Indicators of damage at Russian Arctic airfields demonstrate a perpetual and extensive challenge to their continued operation; the non-exhaustive examples above are indicative of the current extent of the problem as well as a possible preview of what is to come, even at sites that do not currently show serious indications of damage. As climate change causes permafrost to thaw more rapidly, changes to local hydrology are likely to outpace original design efforts to manage their effects on airfield surfaces and supporting infrastructure. Permafrost-induced damage to Russian Arctic airfield surfaces and supporting infrastructure appears to be outpacing the nation’s efforts to anticipate, identify, and address the effects.

INDICATORS OF REPAIRS

Indicators of repairs to airfields are considerably easier to discern in satellite imagery than indicators of permafrost extent and indicators of damage. Imagery analysis has identified that repairs to existing airfields (many from the Soviet era) are completed in an ad-hoc manner. As sections of damaged airfield surfaces are removed and replaced, they offer a large temporal window in which the repair activities can be observed. Similarly, the replacement of large sections of concrete slabs and accompanying equipment entails a large spatial footprint that is easily observable. Onsite repair capabilities can also be observed through satellite imagery as concrete replacement slabs are often stored in the open on parking aprons, aircraft revetments, or nearby ports. As noted from indicators of damage to buildings and other supporting elements of airfields, permafrost thaw can render some infrastructure unusable beyond repair. This level of damage can require new construction to replace the assets in an area that has not yet been fully impacted by permafrost thaw. Additionally, it is useful to observe the construction of new airfields within the Russian Arctic to assess whether new techniques are being employed to combat the threat of permafrost.

Repairs to Existing Airfields

Monchegorsk Airbase, located in Murmansk Oblast on the Kola Peninsula, provides an opportunity to evaluate the airfield repair process from the arrival of materials until the completion of needed repairs. Monchegorsk, a center of copper and nickel mining³⁰, is well connected to Russian industrial centers from which concrete slabs are transported. The airfield’s nearness to the supply chain of necessary materials for airfield repairs allows it to serve as a measure for repair timelines against the remote and isolated airfields, which are more typical of the Russian Arctic. Despite the relative geographic advantages of Monchegorsk Airbase in comparison to most other Russian Arctic airfields, including minimal severe indicators of permafrost within its fence line, progress in addressing clear indicators of damage has been a slow process.

The first indicator of imminent airfield repairs at Monchegorsk is observable in available satellite imagery in June of 2009 as seen in Figure 51. By this date, a large reserve of concrete slabs has been staged on a parking apron on the west side of the runway. Indicators of damage are present in various areas of the airfield at this time, with the TDZ showing the heaviest signs of use.

In August 2009, the new concrete slab reserves were repositioned to a parking apron and taxiway that is adjacent to the runway near the TDZ as seen in Figure 52. Additional slab reserves also arrived in this two-month window and were staged on the central taxiway of the airfield. While the movement of the first batch of concrete slabs could be interpreted to indicate that repair efforts were imminent, the movement appears to have been necessary to accommodate fighter aircraft parking on the apron. The appearance of replacement slabs during the same summer period in which a significant increase in fixed-wing aircraft also arrived at the base is relevant in that it suggests that repairs were needed to support increased future operations. The arrival of new aircraft to the base in 2009 suggests that the airfield surface was deemed at least functional enough to accept an increase in operational capacity in the short-term, despite equal evidence that repairs were needed soon.

By August 2010, slab reserves were visible at both north and central taxiways while fighters occupied the parking apron on which the slabs were originally delivered.

The first indicators of repairs were evident in July of 2013, nearly four years after the replacement slabs arrived at Monchegorsk Airbase. The replacement of concrete slabs within the TDZ is clearly visible, as is a significant reduction in the available slab reserves.

By May 2014, the entirety of the stockpile from the central taxiway and approximately half of the slabs stored on the north parking apron had been used to complete repairs on the north TDZ. The indicators of recent repairs are clear on satellite imagery thanks to the contrast of the newer, lighter-colored slabs adjacent to those that have not been replaced. The repaired area is also clearly surrounded by an exposed layer of sandy soil, likely from the process of re-grading and leveling the foundation during the repair process. The total length of this repaired runway section measures approximately 370 meters.

Many indicators of damage to the airfield surface remain evident even after the repairs of 2013-2014, but additional replacement slabs do not appear until the summer of 2017. Two years later, in June 2019, the first indicators of additional repair work were apparent in the area directly adjoining the section of previous repairs.

This repair effort was completed by September 2019 with an additional 230 meters of repaired runway, but only the slabs along the centerline were replaced as compared to the total surface replacement of the TDZ in 2014.

By January 2021, a new batch of replacement slabs had arrived on the center taxiway at Monchegorsk.

The next visible indicator of completed repairs occurs in August of 2022 when an additional 300 meters of runway centerline was replaced.

In total, since the first batch of replacement slabs arrived at Monchegorsk in 2009, it took over thirteen years to complete repairs for 900 meters of runway. This slow, piecemeal approach to airfield surface repairs at Monchegorsk is typical of all Russian Arctic airfields which show indicators of repairs, and this trend implies a systemic challenge to their proper upkeep in the face of regular use on top of thawing permafrost. The infrequent delivery of replacement material in small batches appears to dictate the pace of repairs at Monchegorsk, and the conservative decision to replace only the centerline of runway sections beyond the TDZ is evidence that the production of new concrete slabs is unable to keep pace with needed repairs.

Dudinka, a small and remote airfield on the Yenisei River, provides further indicators of delayed or abandoned repair efforts. By May 2013, several sections of the airfield surface were removed, and replacement slabs had been staged for repairs.

By the summer of 2022, no indicators of progress on the repairs are evident.

The lack of progress on repairs at Dudinka, despite an apparent desire or need to carry them out, roughly matches the timeline in which repairs at Monchegorsk were heavily delayed. Dudinka’s remoteness and lack of strategic and economic importance are likely factors to blame for the apparent abandonment of repair efforts there. Airfields that support industry, military, and civil flights on a regular basis have significantly less tolerance for delayed repairs; a lack of available replacement slabs threatens to significantly disrupt required operations unless an alternative solution is employed. The airfields at Novy Urengoy and Salekhard show indicators of alternative repair methods which utilize traditional paving methods rather than direct slab replacement. It is notable that these two examples reside at the lowest latitudes of all airfields observed in this study; longer summer seasons and higher average temperatures could be a factor in the feasibility of traditional paving methods for sustainable repairs.

In May 2018, an agreement was signed to modernize Novy Urengoy airport by the end of 2021 with no disruption to airport operations³¹. The appearance of Novy Urengoy’s airfield surface prior to the start of repairs is typical of a Soviet-era airfield constructed completely of pre-stressed concrete slabs.

By July 2021, most of the runway surface was paved over. In comparison to slab replacement repairs, the airfield was resurfaced from the center outwards rather than starting with the TDZs.

By July 2022, the modernization project was behind the stated schedule but close to completion, with indicators of continued paving on parking apron areas.

Salekhard Airport also received similar upgrades to the airfield surface between 2005-2007, when the slab surface of the runway was paved in conjunction with changes to the drainage design. These upgrades are clearly visible in Figures 65 and 66.

Indicators of patchwork repairs to the runway with a paving approach are evident as recently as August of 2021.

Indicators of repairs across Russian Arctic airfields show a trend of long delays and alternative (even if less than ideal) techniques to address damage. While modular concrete slab airfield design was intended to facilitate rapid repairs, imagery analysis suggests that increasing damage due to thawing permafrost has outpaced Russian production and supply chain capabilities to leverage this advantage. The assessment that the production of replacement slabs is a major roadblock to the proper upkeep of Russian airfields in the Arctic is further bolstered in a statement by the deputy director of construction for Yamal LNG regarding building a new airfield to support a $27 billion liquid natural gas facility in Sabetta³², located on the Yamal peninsula. Deputy director Dmitry Monakov stated in 2015, regarding airfield surface construction at Sabetta, that:

“The main problem we faced was that Russian plants have long stopped producing these plates in such industrial volumes. We had to hold a serious competition, and we had to give the winner some time to grow their production capacities before they were able to satisfy our requirements.”³³

Sabetta and other recently built airfields within the Russian Arctic provide an opportunity to view adjustments made to the construction process based on lessons learned and a better understanding of the impact of permafrost on infrastructure.

New Construction

The completion of the airfield at Sabetta in 2014³⁴ provides an example of adjustments to Russian Arctic airfield design, which can be monitored in the future to measure their resilience against thawing permafrost, ideally limiting the need for repairs. Sabetta will be a particularly tough test of any new design implementations, as it was built atop an area showing severe indicators of permafrost threat. Satellite imagery of the site in 2003 shows extensive thermokarst features and vehicle tracks (likely from initial gas field reconnaissance) left in the soft ground.

Left with little choice but to build atop this unstable ground to capitalize on the extraction of natural gas, there are some indicators in the design of the airfield and supporting infrastructure that appear to be designed to minimize the need for future repairs. Sabetta’s airfield consists of a substantial outer berm, well removed from the edges of the airfield surface, and appears to have a drainage system that routes surface water far away from the perimeter towards an existing thermokarst pond. Notably, pre-stressed concrete slabs have been chosen as the best solution for airfield construction in this environment despite previously mentioned indicators of repairs that employ other techniques.

The natural gas extraction site at Sabetta, which the airfield supports, entails dramatic industrial activity which can accelerate local warming. Figure 70 shows the port area of the Yamal LNG site, which is only a small percentage of the infrastructure built in the immediate area. Supporting infrastructure has been built atop sandy foundations, some of which display signs of damage and need for repairs before construction was completed as seen in Figure 71.

Some skepticism regarding the sustained effectiveness of these efforts is warranted, according to Columbia University lecture and energy and marine transport expert Natasha Udensiva:

"I'm not sure how long the project will go on because of climate change. They built the LNG plant on pilings because of the permafrost, and yet everything in the Arctic is melting. In gas fields, in particular there is some danger. There are many holes in the permafrost there already and you don't know when they will open up."³⁵

One such example of this danger is already emerging in the form of a thermokarst pond which has rapidly increased in size; the difference is notable when comparing Figure 72 to 73. This pond is encroaching on the foundation for dormitories and currently supports a pipeline that has been routed directly through its center. The change in the size of the thermokarst pond from 2016-2020 is drastic and will provide a formidable test to the strength of the sand foundation as well as the support piling for the pipeline.

Sabetta is just one example of several recently constructed or completely overhauled Russian Artic airbases which should be monitored for eventual repairs. Russian Arctic bases in the far north, such as Temp Naval Base and Nagurskoye airfield, are other examples of more modern construction methods employed in harsh conditions with significant indicators of permafrost. The recently built “trefoil” style buildings will be particularly useful to observe for resilience against thawing permafrost; a baseline for needed repairs can be established once the first indicators of repairs arise. The construction similarities between the two sites are visible in Figures 74 and 75.

Indicators of Repairs Conclusion

Russia’s ability to repair airfield damage in a timely and sustainable manner lies at the crux of the nation’s Arctic dilemma; the ability to produce, transport, and install replacement concrete slabs is crucial to the sustained operation of Russia’s network of airfields within the Arctic Circle. Imagery analysis has identified no “on-site” concrete slab production capabilities at these airfields, and other sources suggest that the highest quality concrete slabs are produced near Moscow, St. Petersburg, and other sites within European Russia³⁶. The modular design nature of Russian Arctic airfield construction is beneficial in that it allows “piecemeal” repairs only to affected areas versus complete airfield resurfacing, but this concept also demands an efficient supply chain and construction process to minimize airfield downtime. Indicators of alternative methods of repair, such as more traditional paving, are evident but unlikely to provide a long-term solution, particularly at the most remote sites. New airfield construction on permafrost should be monitored for indicators of repairs; this effort would help to establish baselines and determine Russia’s ability to successfully adapt construction practices based on lessons learned from challenges faced at Soviet-era airfields within the Arctic Circle.

CASE STUDY-TIKSI

Previous Tearline reporting published by CSIS in 2019 addressed the significant delays in upgrades to Tiksi Airbase (for the eventual deployment of an S-400 air defense regiment and MiG-31 interceptors) in contradiction to official Russian statements but did not explain the lack of progress beyond possible financial limitations or an attempt at misdirection regarding the true purpose and strategic value of the site³⁷. A target-centric application of permafrost indicators suggests that permafrost-related damages, and a limited supply of replacement slabs, play a significant role in the disparity between official Russian statements on progress at Tiksi as compared to the reality observable in satellite imagery. Evidence of delayed, but still ongoing, repairs to the airfield surface since the CSIS publication in 2019 suggest that Russian ambitions to utilize Tiksi as a MiG-31 staging base remain valid. This suggests that the disprovable Russian statements of progress at Tiksi are meant to avoid a public admittance of the mounting challenges of maintaining airfields that the country faces in the future rather than intended to obfuscate adversaries regarding their intended use of the site. Tiksi has been chosen for a case study application of permafrost-related indicators due to its strategically important location, previous reporting on the site, and because it displays strong examples of each indicator.

Site Orientation

Tiksi Airport was established in the 1950s as a staging base for strategic long-range bombers³⁸. In 2012, Tiksi airport was suddenly closed to all aircraft except for helicopters from 01 October until 31 December with no public explanation³⁹. In 2014, the Russian Ministry of Defense announced that a restoration of the airport would be completed the following year to support the populations of eight new villages to be built in the region⁴⁰. Satellite imagery of the airport shows that no significant improvements were made to the airport during that period; the only notable change is the construction of a large building sometime between 2016-2020 which is visible upon comparison of Figures 76 and 77.

According to a press release from the Russian Federal State Enterprise in August 2016, Tiksi’s runway had been deemed suitable to receive large aircraft due to the extension of usable runway from 1,800 meters to 2,220 meters⁴¹. Despite this claim, satellite imagery shows no improvements to the runway surface until 2021. These recent repairs are located on the south end of the runway and would indeed lengthen the useable runway upon completion, albeit five years after the Russian government claimed the site suitable for large aircraft such as Tu-154s and Boeing-737s.

B. Indicators of Damage

Indicators of damage to infrastructure at Tiksi caused by thawing permafrost are evident on the runway surface, adjacent taxiways, and in areas that were likely excavated for construction purposes. Historical satellite imagery of the areas of the runway most recently under repair reveals visual indicators of damage in those same areas in years prior. Despite the low image quality, dark/ wet spots suggest damaged slabs that are lower than the surrounding slabs or low points on individual slabs. These damaged areas match up with the sections of runway that began to receive repairs in 2021.

In addition to the above indicators, which are visible from 2016 until repairs began in 2021, imagery from September 2022 shows similar indicators across much of the airfield. These wet spots suggest that some slabs sit lower than others and require replacement to ensure that the runway is usable for fixed-wing aircraft.

At Tiksi, erosion is evident underneath portions of the taxiway. Indicators of surface failure on the south taxiway at Tiksi were apparent in 2005 as water near the raised embankment of the airfield began to erode the foundation and subsurface of concrete slabs.

By 2016, the taxiway erosion appears to have worsened, with no evidence of an attempt to repair it.

The taxiway remained in a state of disrepair until June 2021, when the surface slabs above this area were removed. As of September 2022, the surface had yet to be replaced; the construction effort appears to be focused on improvements to drainage and the embankment prior to slab replacement.

Many buildings within the footprint of Tiksi Airport have fallen into disrepair, possibly due to permafrost freezing and thawing beneath their foundations at a more severe rate. It is also possible that the deterioration of buildings is a result of abandonment and general neglect combined with the severe weather of the region. Buildings directly west of the terminal area at Tiksi have deteriorated significantly since 2005; note that permafrost signatures in the form of standing water and ice wedges are more apparent in 2020 as compared to 2005. Figures 82 and 83 provide a comparison of thermokarst feature development over this time period.

West of Tiksi’s airfield, a delivery pipeline running from a now abandoned port to fuel storage tanks near the town of Tiksi completely collapsed sometime between 2006 and 2020. Imagery analysis is unable to conclude whether this damage is deliberate, the result of a severe weather event, thawing permafrost, or some combination of multiple factors. The contrast between Figures 84 and 85 is evidence of the pipeline becoming unusable due to a seemingly rapid vent, whatever the cause may be.

Indicators of Repairs

In the most recent imagery available, significant repairs were underway as of September 2022. In some cases, indicators of damage are visible and obvious prior to repair. The erosion of the taxiways at Tiksi is one such example and appears to have become significant enough to require repairs in 2022 to allow access to the full length of the runway.

Visible indicators of damage to the airfield surface itself are more difficult to ascertain beyond the previously highlighted low spot indicators, but the areas of major slab replacement on the runway are located near the TDZ. These sections under repair cover the same areas mentioned above where indicators of damage were previously present.

Repair Capabilities

Concrete slabs are stored on the west side of the airfield as well as near Tiksi Sea Port. The slab reserve near the port does not appear to have been utilized for current repairs; some stacks of slabs appear to be sinking into rising surface water which has significantly increased since 2005. Figures 88 and 89 are another example of thermokarst indicators resultant from and proximate to human disturbance of the ground.

Slabs for the most recent repairs are first visible on-site in the summer of 2020, with repairs beginning one year later. The most recent available imagery, from September 2022, shows that the runway repairs still needed to be completed at that time. Figures 90 and 91 illustrate a portion of the pre-construction process that occurs onsite.

Indicators of Permafrost

Visual indicators of the presence of and potential threat from permafrost can be seen at Tiksi Airport and in the surrounding area. Significant ice wedge ground coverage, the emergence of more standing water in the summer months, and thermokarst ponds near the airfield and support facilities all pose a threat to the integrity of artificial surfaces and structures. Figures 92 and 93 provide just a few examples of the many permafrost indicators present at Tiksi.

Indicators of increasingly severe thawing of permafrost are apparent to the west of Tiksi Airport, where a thermokarst pond has increased in size since 2005, and a section of an unimproved service road appears to have been abandoned in favor of a diagonal off-road bypass. A comparison of Figures 94 and 95 illustrates how rapidly thermokarst indicators can emerge.