A rapid sea-level rise caused by warming oceans and melting ice sheets and glaciers could impact 1 billion by 2050, the Intergovernmental Panel on Climate Change (IPCC) has warned today in a landmark report.
Authored by 100 experts from 36 countries, the report warns that no part of the world will be spared from the impact of climate change on oceans and the cryosphere, and that the changes could be irreversible.
It highlights how the sea level increased by around 15cm during the twentieth century, and claims this could rise to 60cm by 2100 even if greenhouse gas emissions are cut sharply, and increase to 110cm if emissions grow strongly.
Some island nations are likely to become uninhabitable due to climate-related ocean and cryosphere change, according to the report, with the sea level continuing to rise for centuries.
The researchers also forecast changes in water availability, and increase in marine heatwaves, a rise in storms, the extinction of ice-dependent species like polar bears, and the continued acidification of the ocean.
Launched at the UN's Climate Summit in New York, the report outlines the benefits of ambitious and effective adaptation for sustainable development, and the escalating costs and risks of delayed action.
“The world's ocean and cryosphere have been 'taking the heat' from climate change for decades, and consequences for nature and humanity are sweeping and severe,“ said Ko Barrett, vice-chair of the IPCC.
“By understanding the causes of these changes and the resulting impacts, and by evaluating options that are available, we can strengthen our ability to adapt.“
A total of 670 million people in high mountain regions, and 680 million people in low-lying coastal zones, depend directly on the ocean and the cryosphere – the frozen parts of the planet.
The report gives evidence of the benefits of combining scientific with local and indigenous knowledge to develop suitable options to manage climate change risks to these systems and enhance resilience.
However, it also warns that damage to oceans and the cryosphere will lower humanity's ability to mitigate and adapt to climate impacts, and urges nations to be more ambitious with their emission reduction targets.
“The more decisively and the earlier we act, the more able we will be to address unavoidable changes, manage risks, improve our lives and achieve sustainability for ecosystems and people around the world ,“ said Debra Roberts, co-chair of IPCC Working Group II.
“The ambitious climate policies and emissions reductions required to deliver the Paris Agreement will also protect the ocean and cryosphere – and ultimately sustain all life on Earth.“
Image credit: ©iStock
