According to the latest report of the Intergovernmental Panel on Climate Change (IPCC), governments must take urgent action to address the climate emergency and protect the world’s oceans.
The report, written by more than one hundred climate scientists, based on nearly 7,000 documents, represents the most comprehensive assessment to date, which sets out the severity of the climate impacts through which the oceans and the cryosphere cross Earth).
Sea level rise to one meter by 2100, the loss of up to 90% of coral reefs in the planet’s warm waters and increased frequency of up to 50 times sea heat waves by the end of this century , are some of the consequences highlighted by the report.
According to Estefanía González, coordinator of Greenpeace’s Oceans campaign in Chile «both climate actions and the resilience of our oceans must go hand in hand. The climate crisis is also an ocean crisis. The impacts of carbon emissions on the oceans are greater and faster than anticipated. The ocean is absorbing large amounts of CO2, resulting in ocean acidification that puts marine life and unique ecosystems like corals at risk.»
«Governments must work on concrete measures to abandon fossil fuels and submit national plans to keep temperaturebelow in the coming years, according to the commitment made in the Paris Agreement. In addition, they must agree at the United Nations on a strong Global Oceanic Treaty capable of protecting at least 30% of the world’s oceans through a network of marine sanctuaries,» he explained.
He adds: «As a result of the loss of ice from the Greenland and Antarctic ice sheets and the warming of the oceans, the global average sea level is rising, at an unprecedented rate in 2006-2015, and sea level rise since 1970 mainly to anthropogenic emissions.»
This is how by the end of the century, 1.6c of average global warming could cause you to expect about half a meter of average sea level rise. With an average heating of 4.3c 8 will reach approximately 1 m for 2100 and more than 3.5 m for 2300.
«In this scenario, the importance of protecting glaciers is fundamental, large amounts of carbon dioxide are trapped in the ice and if this melts that carbon will be released into the atmosphere,» Gonzalez said.
The IPCC also presents solutions through policies that help governments mitigate the worst impacts of global warming. It also highlights the challenges facing the oceans as their governance systems have so many barriers, without allowing effective protection.
«This report is another wake-up call for governments sleeping during the climate crisis. We need serious commitment to addressing the climate emergency of our oceans, countries represented at the UN must be able to sign a Global Ocean Treaty to protect our oceans in April next year,» he warned.
Sea level rise by 2100 could be close to one meter if global warming exceeds 3 degrees Celsius, which is where the world’s current governments’ current policies are headed. This could lead to the displacement of millions of people from coastal areas
As sea surface temperatures rise and the oceans become more acidic, marine life and ocean ecosystems will suffer great challenges. Even if global warming is limited to the agreed target of 1.5oC, up to 90% of warm-water coral reefs are projected to be lost.
The widespread thaw of permafrost is projected for this century. Arctic and sub-Arctic permafrost contains 1460-1600 gigatonnes of organic carbon, equivalent to nearly twice the carbon currently in the atmosphere.
By the end of this century, the frequency of sea heat waves could increase 50 times (with temperature increases of 3-5oC) compared to the end of the 19th century.
Anthropogenic CO2 emissions cause chemical changes in the oceans. It is highly likely that the oceans have absorbed 20 to 30% of the total CO2 emissions from human activities, changing the pH of the surface ocean most likely beyond the natural variability at more than 95% of the ocean surface. Ocean acidification is almost certain to continue and be exacerbated by 2100, raising the risks to species that form aragonite platforms in the Polar and subpolar oceans by 2081–2100 under a high-emission scenario.
The oceans are projected to move into unprecedented conditions, with rising temperatures, increased acidification and declining oxygen during the 21st century.
Unless adaptation measures are improved, annual coastal flood damage will increase by an order of magnitude from 2 to 3 by the end of the century compared to today’s
Unprecedented weather conditions are developing in the ocean. Increased precipitation, wind and extreme sea level events associated with some tropical cyclones have increased due to climate change.
Projected increases in tropical cyclone intensity and precipitation will exacerbate extreme sea levels and hazards in coastal areas.
El Niño’s extreme events are expected to occur about twice as many times as in the 21st century
The National Snow and Ice Data Center has just announced the minimum extent of Arctic sea ice for 2019. It has 4.15 million square kilometers (1.6 million square miles).
Summary of the report here