LIVING in Malaysia and its tropical climate, we may well ask ourselves: “Why should we be worried about areas of our northern hemisphere where the soil and subsoil is near permanently frozen?” Permafrost – a term first coined in 1943 – refers to soil or rock with a temperature remaining at or below zero degrees Celsius for two or more years and usually is used with reference to areas surrounding the Arctic and Antarctic, but can also be found in high mountainous regions such as the Himalayas and Andes. It has even been found on Tanzania’s Mount Kilimanjaro and until 3,000 years ago on Mount Kinabalu!
Usually occurring at a depth of up to five to six metres, this permafrost layer freezes and thaws annually in its upper or active layer thereby causing headaches for oil pipeline and thermal heating engineers in Alaska and Iceland. A quarter of the ice-free land area of the northern hemisphere is influenced by permafrost. Much of this land is located not only in the previously mentioned countries but also in northern Canada, Greenland, and Siberia.
During the Pleistocene Ice Ages, about 1.4 million to 11,000 years ‘Before the Present’ (BP), much of southern Europe, eastern Asia and North America were subjected to permafrost conditions beyond the southern edges of the continental ice sheets. Evidence of this is seen in plenty where frost riven stones mixed with soil sludged downslope from mountainsides and hill masses onto valley floors when the permafrost eventually melted. These deposits are referred to as solifluction head. The permafrost once held these hillsides together in a stable state but, upon thawing, the slopes became unstable and accordingly adjusted their angles of rest.
Vast carbon stores being released
Ice is a great absorber of carbon dioxide and thus the frozen state of permafrost areas allows huge amounts of that gas and methane to be naturally stored. It is calculated that twice as much of these gases exist in a frozen state than are currently in our atmosphere. A recent study has revealed that carbon emissions from thawing permafrost could well be in the order of 4.35 billion metric tonnes a year during this century alone. This, surprisingly, is about 50 per cent as much as present day fossil fuel emissions. Undoubtedly, the tundra areas of our world are as important in the storage of albeit fossil carbon as our present day rainforests are in absorbing atmospheric carbon dioxide.
Thinning of the Arctic Ocean’s sea ice
New research by Oxford University’s Department of Earth Sciences, together with teams from the Geological Survey of Israel, Northumbria University, UK, and the Institute of the Earth Crust Academy of Sciences, Irkutsk, Russia joined forces with the local Irkutsk Cave Exploration Club to provide evidence from Siberian caves implying that the summer sea ice in the Arctic Ocean plays an essential part in stabilising permafrost areas, thus contributing to withholding their carbon content. Drip stone formations of stalactites and stalagmites in these caves provided evidence that these formations were directly related to past summer episodes when the Arctic Ocean was devoid of sea ice.
The Arctic sea ice has decreased significantly in recent years and the Arctic Ocean is expected to be ice-free in summertime for many decades to come.
Already we are seeing summer shipping movements from the Atlantic to the Pacific Oceans along the once legendary and much explored Northwest Passage!
It is logical that the absence of summer sea ice will lead to increased heat and evaporation from the sea into the atmosphere with warmer air passing overland into Siberia.
This will lead to an increase in autumnal snowfall and the snow blanketing the ground will act as insulation from the bitterly cold winter temperatures.
In turn, the average annual ground temperatures will increase allowing the permafrost to thaw and thus releasing the carbon dioxide which has been trapped there for millions of years.
Re-wilding and mega-faunal engineering
During Interglacial periods during the Pleistocene, the tundra or permafrost regions of the Arctic were clad with a type of grassland ecosystem. Fossil evidence has revealed that during these times of ameliorating climates the thawing permafrost of today has exposed an average of one mammoth, five bison, 7.5 wild horses, 15 reindeer, 0.25 cave lions and one wolf per km of this area. This revelation by Oxford University’s Environmental Change Institute approximates to the present day animal density in East Africa’s savannah grassland game reserves.
As today’s climate warms and the permafrost continues to thaw, it is suggested that the tundra ecosystem can be restored to its previous grassland state by reintroducing herds of bison and wild horses as grazers of tree sapling thus allowing grass to grow. The grasses would then trap the released gaseous emissions from the thawing permafrost in their rooting systems. Such animals would be ‘eco-engineers’ in slowing the rate of permafrost thaw. The gradual diminishing of rainforest areas has received worldwide attention regarding the loss of natural carbon stores, yet we need to look carefully at the loss of sea ice, permafrost thawing and subsequent release of stored carbon dioxide into our atmosphere and the inevitable rise in sea-levels.
The Pleistocene Park
There is hope for the Arctic’s permafrost areas which is no better demonstrated than in The Pleistocene Park, a family-run restoration project by Sergey and Nikita Zimov along the Kolyma River in North East Russia. There, the reintroduction of hardy animals is taking place with ‘promising results’, in a 144 sq km nature reserve, which was established in 1988. This is a serious lifelong attempt to recreate the Mammoth Steppe Ecosystem of about 11,000 years BP. This park now boasts herds of reindeer, elk, Yakutian horses, muskoxen, European bison, yaks, sheep, which have been interbred to withstand Siberian winters, Kalmyki cattle, and Plains American bison. Mountain hares, marmots, red and Arctic foxes, Arctic ground squirrels, Eurasian lynx, sable, and stoats already existed
Experiments in the genetical engineering of mammoth DNA (derived from the thawing permafrost) implanted into elephants may eventually see mammoths again grazing there. In the fullness of time it is hoped to reintroduce the highly endangered Siberian tiger.
Re-wilding can only be achieved at a cost, as we well know in the costs of planting trees in urban areas to create urban lungs. Cleary, we seriously need to think about the amount of money world governments need to set aside to offset climate change or at least to attempt to slow global warming down.
For fascinating viewing, do visit www.pleistocenepark.ru and click on the 25-minute video, which is an award-winning documentary.
For further scientific evidence read the Philosophical Transactions of the Royal Society (Jan 27, 2020) entitled, ‘Pleistocene Arctic mega-faunal ecological engineering as a natural climate solution?’