In order to preserve as much Arctic sea ice as possible, several solutions are being studied. One of these involves the use of autonomous drones equipped to help thicken it.
The use of underwater drones, supported by the use of artificial intelligence techniques, is one of the possibilities under research consideration to slow the melting of Arctic sea ice.
There is less and less time to intervene: according to a study published in Nature – “Observationally-constrained projections of an ice-free Arctic even under a low emission scenario” – it could melt almost completely within the next decade, i.e. 20 years earlier than estimated in the IPCC (Intergovernmental Panel on Climate Change) sixth report.
The reduction of the albedo effect due to the disappearance of sea ice in the Arctic is already responsible for about 25% of global warming, predicts a study conducted by scientist Jennifer Francis of the Woodwell Climate Research Centre.
What is needed is the refreezing of the Arctic, which – as the well-known naturalist and populariser of science David Attenborough put it -“would be a huge defence against global catastrophes currently threatened by global warming“. This wish of his inspired the birth of the Refreezing the Arctic Foundation, a project coordinated by David King, former UK Chief Scientific Advisor and Special Representative on Climate Change.
In addition to a geoengineering idea such as the Marine Cloud Brightening – which we will discuss later – the initiative counts on the active participation of the Centre for Climate Repair at Cambridge University. Working with the same Centre is the British start-up Real Ice, founded at the Welsh University of Bangor, which is implementing another solution, aimed at thawing ice using water pumps. Inserted into the first winter’s ice, they pump seawater into the surface (which freezes rapidly), thus helping to increase its thickness.
The project, born from the theories of some scientists, has been implemented by the start-up, which has already successfully participated in the United Nations accelerator for Tomorrow. The aim is to develop a system of underwater drones equipped with pumps and other systems (including one to supply power to green hydrogen), capable of providing the necessary interventions to allow water to be fished out from under the ice sheet and gushed to the surface.
TAKEAWAYS
The importance of Arctic sea ice
Crucial in maintaining the energy balance of the Earth and influencing the global climate, Arctic sea ice, due to its white surface, reflects sunlight back into space. In other words, it does not absorb much solar energy, helping to maintain relatively low temperatures in the Arctic.
However, as sea ice recedes throughout the year, the darker, open oceans absorb more solar energy, generating more heat that accelerates melting. For this reason, the Arctic is warming at two to three times the rate of the rest of the planet, explains the National Snow and Ice Data Center (NSIDC).
Sea ice in the Arctic and Antarctic is of vital importance: it helps regulate heat, moisture and salinity exchanges in the polar oceans and is able to influence ocean currents, which also has a significant impact on the well-being of local fauna.
Unfortunately, there is a noticeable and progressive decline. Between 1979 and 2021, sea ice cover in the Arctic at the end of summer has decreased by 13% every decade, compared to the 1981-2010 [source: “Climate Change: Arctic sea ice summer minimum” – National Oceanic and Atmospheric Administration].
According to all emission scenarios, even the most optimistic ones, the phenomenon of the Blue Ocean Event will take place within the next decade. It means witnessing an ice-free summer, an event that will occur when sea ice falls below one million square kilometres.
Once this point is reached, it is very difficult to go back and recreate it. The ice that is recreated at the beginning of each winter is very fragile, while, if it manages to remain until the following year, it contributes to the thickening of the ice cap that is already present.
Thickening Arctic ice with underwater drones
Urgent measures are needed that can, at the very least, significantly slow down the phenomenon. Among the solutions devised in recent years, the technique of ice thickening (ice thickening) was illustrated in 2017 by Steven Desch, an astrophysicist at the School of Earth and Space Exploration at Arizona State University. To this end, he envisaged increasing Arctic sea ice production by using wind power during the Arctic winter to pump water to the surface.
Desch himself is on the scientific committee of the start-up Real Ice, along with other scientists including Shaun Fitzgerald, director of the Centre for Climate Repair in Cambridge, who published a paper last November – “Ice Thickening” – in which he illustrates the method developed by the Welsh innovator.
This method is based on the principle of freezing the water underneath the ice, pumping it up and making it flow over its surface. As the startup’s Co-Ceo, Italian Computer Scientist Engineer Andrea Ceccolini, explains:
“… if one pours water over Arctic ice, it immediately freezes. It is, therefore, a matter of exposing as much water as possible, taking it from under the ice layer“
If the ice cap acts as an insulator, hindering the formation, similarly, the exposure of water in contact with the upper surface and extremely cold temperatures allows for almost immediate freezing.
“In three to four days, in our last test in Canada, we added 30 centimetres to the thickness of the ice in an area of about 4000 square metres, with a simple 600-watt pump,” similar to those used in swimming pools, he adds.
The holes are drilled using an ice coring device, a kind of telescopic tube that is heated by a resistor, with energy from a battery. This type of technological solution is already being used for ice coring even for depths of tens of metres;
“For the intervention that we want to put into practice with the underwater drones, a metre depth or even less (30-60 cm) is enough and the contained ice will be ejected once the layer has been completely perforated, to make room for the pump outlet pipe,” explains Ceccolini himself.
Operating underwater is easier, given the extreme atmospheric conditions outside, with temperatures of -30/40 °C and winds of 50/70 km/hour. This is where the underwater drones come in.
Autonomous underwater vehicles (AUVs) are unmanned underwater robots (as other drones or autonomous software defined vehicles). Of different lengths, they are similar to other autonomous underwater vehicles used in various fields. They are used in ocean research, but also in telecommunications. In the case of the Arctic drillings, they are compact vehicles, about 1.5 metres in length, more than enough to carry the pump and heated hose and carry out the necessary operations.
The role of artificial intelligence in supporting underwater drones
In order to make this possible, it is necessary to ensure wide automation, providing the necessary intelligence both on board and in the control area, which will allow the underwater drones to be brought over the ocean and make them work together as a coordinated whole.
The AUVs will need to operate in a manner typical of the swarm robotic.
“They will need to collaborate with each other in a very intensive and close manner, because they will have to consider a number of factors, from weather conditions to the ice on which they operate, with a resilient network capability and whose nodes operate in a collaborative manner.”
To make this possible, artificial intelligence techniques are needed, which are envisaged on several fronts.”There are several areas where we can apply AI methods that are already well established. One is in the area of computer vision, exploiting Lidar technologies and solutions that can enable the most optimal image recognition.
Another element that will require the adoption of AI concerns the ability to move around in the marine environment, recognising and avoiding obstacles.For this vertical and horizontal sonar will be used, so as to realise a virtual map of the environment in which one is navigating.
“It will be necessary to adopt deep learning models that will require continuous learning. Existing consolidated solutions will be adopted to produce the richest volume of data, to enable the drones to move swarm robotic based on an evolved IoT network,” further specifies the Real Ice Co-Ceo.
Green hydrogen from renewable sources to power the system
To power the platform where the underwater drones and the AUVs themselves are housed, energy is needed. It will rely on renewable sources, to minimise the impact.
Real Ice intends to deploy green hydrogen and fuel cell technology, so as to produce and store the energy carrier where it is needed and when it is needed.
“The idea is to produce green hydrogen all year round with renewable energy and then bring it to hubs, platforms in the middle of the ocean, each with the task of operating over an area of up to 2000 square kilometres“.
The hubs are then used to supply the underwater drones – between 100 and 300 devices per hub – which work by moving progressively to cover the entire surface area. Each drone will be equipped with a 2-kg container of green hydrogen stored at 700 bar; by means of fuel cells, it will have to generate at least 40 kWh, being able to do the work of transporting, drilling and pumping.
“The expectation is to build an economically sustainable system: the goal is to arrive at a cost of less than $10,000 per drone, enabling a scalable project to be implemented in three years. The total construction cost is expected to be around $5 billion. Then there are the costs of the hubs and the overall system, which brings the total expenditure to USD 10 billion‘.
This is a large figure, but when climate mitigation measures are taken into account, they are significantly reduced: just considering the fires in California in 2017-2021, they caused an estimated average annual loss of $117.4 billion [source: Gordon and Betty Moore Foundation].
Green hydrogen will be produced by electrolysis with electricity generated by wind and photovoltaics.
“We will need to rely on specialised companies to implement this opportunity in an area that is extreme in terms of weather and climate conditions. But the first pilot applications do not require a great commitment in terms of production. The first ‘visible scale’ project, 100 square kilometres in a Canadian bay, will require a wind turbine of about 300 kW. Some operators have already brought wind power and even photovoltaics to these latitudes, so the possibility of using them in this context exists,’ Ceccolini notes.
Other solutions to preserve Arctic sea ice
In addition to ice consolidation using underwater drones, there are several technological solutions under study that are the focus of the Center for Climate Repair.
One of these, under consideration by the Refreezing the Arctic Foundation, involves Marine Cloud Brightening (MCB): it refers to an albedo modification technique, which aims to increase the reflectivity – and perhaps even the lifetime – of some clouds in order to reflect more sunlight back into space and partially offset some of the impacts of climate change. This technique seeks to concentrate cloud moisture into a large number of smaller droplets. In doing so, the cloud cover whitens, allowing it to reflect more sunlight.
Then there is stratospheric aerosol injection (Stratospheric Aerosol Injection – SAI). It involves the use of aircraft as well as balloons or giant tubes that release sulphur dioxide from the surface into the upper atmosphere to increase the Earth’s atmospheric albedo (reflectivity). This method of limiting the sun’s rays ideally mimics the phenomenon of volcanic eruptions, which emit millions of tonnes of sulphur dioxide into the atmosphere.
Specifically, a team of scientists hypothesised – in an article in Environmental Research Communications – the use of high-altitude airplanes as a means of dispersing aerosol particles in the atmosphere. Once released at an altitude of about 13,000 metres, higher than that of airliners, these aerosols gradually move towards the poles, causing a slight reduction in sunlight reaching the surface.
Another idea is based on the use of so-called ‘seabed curtains‘, a name inspired by the project Seabed Curtain, led by climatologist John Moore of Lapland University. It involves applying fabric to prevent warm water from lapping the base of ice shelves, a concept derived from a 2018 proposal to build underwater docks. Each curtain, approximately 100 metres high, would be anchored to the seabed via a foundation and would be buoyant.
Equally important is research that studies the behaviour and dynamics of Arctic sea ice and employs artificial intelligence and machine learning. These include the digital twin project for Earth and space observation, which is being developed by the National Oceanic and Atmospheric Administration, together with Nvidia and Lockheed Martin;
Glimpses of futures
The solutions devised, designed and partly implemented to attempt to reduce the melting of Arctic summer sea ice, from the use of underwater drones to thicken the ice cover to other ideas under consideration,require funding and further investigation to assess their actual realisation. The objective is a virtuous one: to protect an asset of global significance as much as possible. These are tasks and responsibilities that must also be taken on at a political and institutional level, because the further reduction of polar ice opens up dramatic scenarios. As the WWF recalls, the Arctic and Antarctic are the world’s refrigerator:
“Because they are covered in white snow and ice that reflect heat back into space, they balance out other parts of the world that absorb heat. Less ice means less reflected heat, which means more intense heat waves around the world“
It is good, now, to anticipate the possible future scenarios by analysing – by means of the STEPS matrix – the impacts at social, technological, economic, political and sustainability levels.
S – SOCIAL: the melting of Arctic ocean ice will further exacerbate global warming and the rising sea level, with major knock-on effects, starting with those living along the coasts. Currently, about 40 per cent of the world’s population lives within 100 kilometres of coastal areas [source: ONU] and more than 600 million reside in coastal areas less than 10 metres above sea level [source: “Assessing population exposure to coastal flooding due to sea level rise” – Nature].
T – TECHNOLOGY: the solutions under consideration by the scientific community that can reduce or delay the melting of Arctic ice are, in part, theoretical and must be studied very carefully to prevent them from not only being ineffective, but also having a negative impact on the environment. Already today, however, thanks to the combination of various instruments (satellites, Lidar, drones) with artificial intelligence systems, it is possible to rely on increasingly accurate weather and climate forecasts to better understand the situation of Arctic sea ice.
E – ECONOMY: the cost involved in transforming some of the ice-preserving projects and solutions in the Arctic is not ‘light’. We have mentioned the ice thickening project; in the case of the Seabed Curtains, however, the authors of the project for the installation of the curtains estimate an expenditure of $40 to $80 billion, to which two billion dollars per year must be added for maintenance. But the costs resulting from the consequences of melting ice must also be taken into account. Consider sea level rise: the construction and maintenance of coastal protection is expected to cost about USD 40 billion per year for every metre of sea level rise [source: Artic Centre].
P – POLITICAL: the melting of polar ice is a huge problem, which affects all countries in the world. However, a number of factors affect the chances of taking prompt action. One example is the Arctic Council, the main intergovernmental forum promoting cooperation in the Arctic. The invasion of Ukraine by Russia (among the Council’s member countries) has profoundly influenced Arctic geopolitics and security dynamics, as the Arctic Institute has pointed out.
S – SUSTAINABILITY: the disappearance of Arctic ice has several environmentally relevant effects and impacts, affecting the rise in temperature and the resulting enhanced effects of global warming. Not only that: significant amounts of methane and methane hydrates are stored under the Arctic submarine permafrost. The thawing of this layer results in their release into the environment and atmosphere, further worsening global warming. [source: “Groundwater springs formed during glacial retreat are a large source of methane in the high Arctic” – Nature Geoscience].
