The Arctic is the fastest-warming region on Earth. Last year, an international team of climatologists discovered that the Arctic could warm even 4.5 times faster than the rest of the globe. It means that in the next 25 years, we can experience a no-ice in the Arctic in the summer season.
Why is it like that? Well, the phenomenon responsible for the unprecedented heating of the North Pole area is the so-called polar (or Arctic) amplification. What is it all about?
Polar amplification – what is it?
In general, a polar amplification means that at high latitudes, the surface temperature warming exceeds the global average temperature change. There are a lot of more or less certain causes impacting the Arctic amplification.
Scientists most frequently point to reducing the ice albedo, cloud feedback, and oceanic heat transport system.
Ice-albedo feedback due to diminishing sea ice
The loss of sea ice is one of the most frequently cited reasons. When the reflective ice melts, a darker ocean dominates. The ocean’s surface absorbs more solar heat than the surface of snow and ice. This means that the fall of the ice reduces the albedo (the ability to reflect sunlight) of the surface and contributes to the increase in temperature.
Cloud feedback
Clouds play a crucial role in polar amplification because they can both amplify and mitigate the warming effects in polar regions.
Cloud feedback is a complex phenomenon meaning clouds’ response to temperature changes caused by external forcings, such as greenhouse gas emissions. It can be positive or negative, depending on how clouds interact with the Earth’s radiative balance.
Positive cloud feedback occurs when increasing temperatures lead to more cloud formation, which in turn traps more heat in the atmosphere, further enhancing the warming effect. Positive cloud feedback can contribute to polar amplification in the polar regions by trapping more outgoing longwave radiation, reducing the net heat loss from the polar regions, and intensifying the warming.
Negative cloud feedback, on the other hand, occurs when increasing temperatures lead to changes in cloud properties that enhance the Earth’s albedo (reflectivity), resulting in more incoming solar radiation being reflected back to space. This leads to a cooling effect. Negative cloud feedback can partially offset the warming and dampen polar amplification. The exact impact of cloud feedback on polar amplification is still an area of active research, and uncertainties are involved.
Ocean heat transport and storms
Ocean currents play an unprecedented role in climate regulation. One of the most powerful of them is the Gulf Stream, which is a fast-flowing, warm ocean current that originates in the Gulf of Mexico and moves northeastward along the Atlantic coast of North America before crossing to Europe. The movement of the Gulf Stream keeps Europe from being much colder than it really should be because of its northern latitude while also impacting precipitation across large parts of Africa and South America.
The global warming phenomenon we’re currently experiencing is also believed to be linked to the weakening of the Gulf Stream. According to Nature magazine, the speed of the Gulf Stream system has declined by 15% since the middle of the 20th century. The further changes can significantly affect climate stability and drastically impact different parts of the world – in particular, Europe.
As for storms, they transmit the heat from the surface to the atmosphere, where the global winds move the heat towards northern latitudes. Massive storms are a form of temperature regulation at the equator. They reduce the global warming impact on tropic locations but boost polar amplification.
Polar amplification in numbers
As mentioned in the introduction, polar amplification is responsible for an even 4.5 higher pace of warming in the Arctic than in the rest of the World. But let’s take a closer look at the two essential elements of the Arctic climate – permafrost and Arctic sea ice.
Permafrost
Permafrost is incredibly important for the Earth’s climate because of the enormous carbon and methane reservoirs in Arctica. A decrease in permafrost areas will release gigatons of greenhouse gases that are currently trapped by permafrost. According to scientists, it will have a moderate impact for the following decades, but it can significantly impact in a matter of centuries.
It’s worth mentioning that 15% of land in the Northern Hemisphere contains permafrost. Moreover, the Artic permafrost has warmed by 2 – 3 °C in the last 50 years. We can observe the strongest warming of permafrost in parts of Northern Alaska, where the average temperature rose over 3°C throughout half a century. The near-surface permafrost area has decreased by 37%, and according to predictions, it will decrease by 87% compared to the 1980s.
Arctic sea ice
The annual mean Arctic sea ice extent decreased from 1979 to 2019 by even 43%. The ice cover of the sea is also getting younger and thinner than in the past. According to observations, it is likely the sea ice will continue declining in the range of 3.5 to 4.1% per decade (range of 0.45 to 0.51 million square kilometers per decade) and very likely in the range of 9.4 to 13.6% per decade (range of 0.73 to 1.07 million square kilometers per decade) for the summer sea ice minimum (perennial sea ice).
From reconstructions, we know that over the past three decades, Arctic summer sea ice retreat was unprecedented, and sea surface temperatures were anomalously high in at least the last 1,450 years!
Polar amplification – why is it so crucial for the planet?
Polar amplification, with its accelerated warming of the Arctic, profoundly impacts the planet. The Arctic’s role as a global air conditioner and its influence on weather patterns make it a crucial component of our climate system.
This phenomenon disrupts temperature gradients, leading to extreme weather events and altering precipitation patterns in mid-latitude regions. Furthermore, it releases greenhouse gases as diminishing sea ice and thawing permafrost exacerbate climate change.
All these consequences extend beyond the environment, affecting ecosystems, biodiversity, and human livelihoods. Moreover, political implications arise as countries compete to access newly accessible resources and shipping routes. It is important to note that the full extent of the consequences is still uncertain.
Addressing polar amplification necessitates global efforts to mitigate climate change, reduce emissions, and protect the fragile Arctic ecosystem. Urgent action is imperative to safeguard our planet’s future, as the fate of the Arctic carries potentially significant and far-reaching consequences.
About The Author
Michal Jonca is a digital nomad working as a Content Writer for Passport Photo Online and a professional leader in adventurous travel experiences.
This piece was prepared online by Panuruji Kenta, Publisher, SEVENSEAS Media