All people on Earth depend on the oceans and cryosphere in one way or another. The cryosphere is those parts of the Earth, located at and below the land and ocean surface, that are frozen, including snow cover, glaciers, ice sheets, ice shelves, icebergs, sea ice, lake ice, river ice, permafrost, and seasonally frozen ground. This is the subject of a recent Special Report by the United Nations Intergovernmental Panel on Climate Change (IPCC) called ‘The Ocean and Cryosphere in a Changing Climate’ prepared by 104 scientists from 36 countries and based on 6981 peer reviewed scientific reports.
Permafrost is any ground that remains completely frozen (0°C) or colder for at least two years. These permanently frozen grounds are most common in regions with high mountains and in Earth’s higher Northern and Southern regions, near the North and South Poles. What happens to the Permafrost as the world’s climate warms up, is of huge interest to us all.
193 of the 196 countries that exist on our planet are members of the United Nations. The IPCC draws upon research and studies by hundreds of scientists from all member states. The UN has been intensifying its efforts to inform and warn Governments of the grave consequences that we will all face from the climate crisis, biodiversity and habitat losses and ongoing mass extinction events caused entirely by humans.
All the 193 Governments members of the UN receive the detailed UN reports and a Summary for Policymakers (SPM). The SPMs outlines the key findings of the reports and are structured in three part, (a) Observed Changes and Impacts, (b) Projected Changes and Risks and (c) Implementing Responses. All Governments are extremely well informed on the subject, in fact far more informed than we are of the dire consequences of inaction. Yet they do nothing, or simply not enough – apart for the notable exceptions of Costa Rica, New Zealand and possibly Austria (1%). Future generations (should they exist) would certainly consider the lack of political will to take sufficient and effective action to protect and restore nature, to have been a crime against humanity.
The Ocean and Cryosphere are of critical importance for people. The global ocean covers 71% of the Earth surface and contains about 97% of the Earth’s water. Around 10% of Earth’s land area is covered by glaciers or ice sheets. The oceans and cryosphere support unique habitats, and are interconnected with other components of the biosphere through global exchange of water, energy and carbon. The report addresses how the oceans and cryosphere are reacting to the greenhouse gas emissions and ongoing global warming. It also points out ‘Feedbacks’.
Feedbacks are those chain reactions of cause and effect that, having been set in motion, are impossible to control. It also points out the dramatic changes with uncertain outcomes over the coming decades to millennia, that cannot be avoided. The report points out the planetary ecosystems’ destruction thresholds leading to abrupt change and irreversible consequences. If you are alarmed by this language, you should be – welcome to the real world. ‘Feedbacks’ is a scientific term that sounds harmless. However, in this context, it is the stuff of Armageddon and the word should send a shiver down your spine.
Human communities in close connection with coastal environments (680 million people), small islands, polar areas (4 million people) and high mountain regions (670 million people), where glaciers, snow or permafrost are prominent features of the landscape, are all particularly exposed to catastrophic change, such as sea level rise, extreme sea conditions and shrinking cryosphere. Other communities further from the coast are also exposed to extreme weather events as a result of changes in the ocean.
The oceans and cryosphere provide people with food and water supply, renewable energy, and benefits for health and well-being, cultural values, tourism, trade, and transport. The health of the ocean and cryosphere is critical to every aspect of the UN Sustainable Development Goals.
Over the last decades, global warming has led to the widespread melting of the Earth’s frozen waters and the thawing of frozen lands. This has meant reductions in the volumes of ice sheets and glaciers and reductions in snow cover. The Arctic sea-ice extent and thickness has diminished due to an increase in surface air temperature of more than double the global average over the last two decades and the warming up of the permafrost.
Permafrost temperatures have increased to record high levels since 1980. The Arctic and surrounding frozen lands contain 1460–1600 Gt organic carbon, almost twice the carbon already in the atmosphere. This trapped methane and carbon dioxide (greenhouse gases) stored in the ground by low temperatures is at high risk of being released due to thawing caused by global warming in any near future.
Global-scale glacier mass loss, permafrost thawing, and decline in snow cover and Arctic sea-ice are expected to continue up to 2050 due to surface air temperature increases, with unavoidable consequences such as flooding and other natural disasters. The Greenland and Antarctic ice sheets are projected to lose mass at an increasing rate throughout the 21st century and beyond. Scientists are predicting, with a high degree of confidence, that the permafrost thawing will become more widespread. The speed and magnitudes of these catastrophic changes are projected to increase further in the second half of the 21st century.
We need to appreciate that a small increase of 0.5°C or 1°C in the Earth’s average temperature would have a disproportionate climatic effect. Arctic sea ice loss is projected to continue through to 2050, with differences thereafter depending on the extent of global warming. For example, in the case of a stabilised global warming increase of 1.5°C, the annual probability of a September without sea ice in the Arctic by the end of century is approximately 1%. This probability rises to up to 35% for stabilised global warming of 2°C.
When permafrost thaws the organic matter in the permafrost does as well and starts to decay. The microorganisms start to eat it. If there is no oxygen the microorganisms make methane. If there is oxygen they make carbon dioxide.
In 2015 the nations of the world agreed to limit the mean Earth temperature increase from pre-industrial base (mid-19th century) to 1.5°C. This was to be achieved by reducing fossil fuel burning and therefore greenhouse gas emissions. This so-called Paris Agreement was an unmitigated fiasco. Firstly, the highly polluting shipping and airline industries were exempted. Secondly, greenhouse gas emissions continued to increase year on year all the way to 2019.
Permafrost melting releases carbon dioxide and methane. Methane in the atmosphere is, in the short to medium term, 25 to 100 times more conducive to global warming than carbon dioxide. The thawing permafrost is one of those Feedback loops mentioned earlier where warmer temperatures cause the permafrost to thaw and to release greenhouse gases that in turn cause increased warming that then thaws more permafrost. This type of Feedback would cross the threshold of irreversibility. Governments, and the CEOs of just 100 companies causing 71% of the world’s emissions, are gambling away our future. Should the permafrost Feedback gather momentum most of life on Earth, including us, would be on death row counting the years, or even months.