In the Arctic, the damage is now irreversible: summer sea ice will melt completely for the first time in at least 8,000 years.
The melting will be cyclical and will happen at least once before 2050.
Reducing CO2 emissions will serve to prevent further irreversible damage to the cryosphere.
We can’t negotiate with melting ice caps. Before the start of COP27 in Egypt, the International Cryosphere Climate Initiative published its State of the Cryosphere 2022 report, which contains a stark warning about what awaits us in the near future, starting in the Arctic.
The ICCI’s conclusions are deeply troubling: total loss of summer sea ice in the Arctic is inevitable and will very likely happen before 2050.
Irreversible impacts in the Arctic within human timescales
The terminal diagnosis for Arctic summer sea ice comes a year after the first report on the state of the cryosphere, which was also released in time for COP26 in Glasgow. The first edition gave a detailed description of the implications of a lack of action in terms of reducing emissions, including the potential collapse of the western Antarctic ice sheet, the disappearance of glaciers outside of polar regions, and the unstoppable rise of sea levels all over the world.
At the time, the most devastating impacts still seemed to be distant from the most populated regions of the cryosphere, but the news has worsened in the past year. In March 2022, temperatures in Antarctica hit 40 degrees above average, while in September, record temperatures were recorded in Greenland and the Alps, which have lost over 5 per cent of their glaciers. All of this happened alongside the first massive documented permafrost methane release.
All these impacts are irreversible in human timescales. The 2022 report highlights the alarming conclusion of the sixth IPCC assessment report, according to which, even with very low emissions, total Arctic summer sea ice loss will occur at least once, and likely before the year 2050.
Announcing the launch of a new report – State of the Cryosphere 2022: Growing Losses, Global Impacts. Authored and reviewed by more than 60 leading #cryosphere scientists.
The presentation of the report at the Cryosphere Pavilion in Sharm el Sheikh emphasised that, although we can no longer prevent or change this future scenario, the containment of global heating within the 1.5-degree limit can drastically reduce the risk of exceeding other thresholds that could cause increasing damage to the cryosphere.
“This occurrence lies outside modern human experience: the Arctic Ocean has not been ice-free for at least 8,000 years; and probably, not for 125,000 years,” said Robbie Mallett, an Arctic sea ice researcher at University College London. “The impacts and feedbacks will be global, and dangerously unpredictable”.
“Our planet’s melting ice pays no attention to climate pledges and NDCs (Nationally Determined Contributions, the non-binding national climate change action plans, ed.). It responds only to the level of CO2 and warming in the atmosphere, which shows no sign of pausing. Until our CO2 rise slows, halts and begins to decrease, the ice will continue to respond as it always has: to the only number that really matters,” said Pam Pearson, Director of the ICCI.
The two lower-emission climate scenarios forecasted by the IPCC are the only ones that have some chance of preventing catastrophic events that cannot be reversed for centuries, or even tens of thousands of years. Whether these thresholds will be exceeded has to do with political decisions. Hopefully, these warnings are clear in the minds of the decision-makers at COP27.