IPCC Ocean & Cryosphere Report: Humans are Rapidly Turning Oceans into Warm, Acidifying Basins Hostile to Lifehttps://www.vox.com/platform/amp/energy-and-environment/2019/9/25/20881595/ipcc-report-ocean-cryosphere-2019A new UN report warns changes to the oceans this century will be “unprecedented.”https://report.ipcc.ch/srocc/pdf/SROCC_SPM_Approved.pdf“The ocean has been acting like a sponge, absorbing heat and carbon dioxide to regulate global temperatures, but it can’t keep up,” IPCC vice chair Ko Barrett said at a press conference. “The world’s oceans and cryosphere have been taking the heat of climate change for decades. The consequences for nature and humanity are sweeping and severe.”
On Wednesday, the IPCC, convened by the UN to assess climate science, released a summary of the report on the oceans and frozen regions of the world, or cryosphere, for policymakers after more than 100 scientists reviewed thousands of scientific papers. The findings are immense and comprehensive, and seeing them all in one place is sobering.
In all, “over the 21st century, the ocean is projected to transition to unprecedented conditions,” the report warns. The ocean will be warmer, more acidic, hold less oxygen, be more greatly stratified (i.e. the top and bottom layers won’t mix as much). Ocean heat waves are growing more common, and it’s likely extreme El Niño and La Niña systems will form, leading to more extreme weather around the globe.
... The report makes it clear: the two largest ice sheets on Earth — the Greenland ice sheet, and the Antarctic ice sheet — are melting at an accelerating rate. “Mass loss from the Antarctic ice sheet over the period 2007 – 2016 tripled relative to 1997 –2006,” the report finds. “For Greenland, mass loss doubled over the same period.”The new IPCC report finds that “between 1979 and 2018, Arctic sea ice extent has very likely decreased for all months of the year.” Additionally, every year, the amount of ice older than five years (which is thicker and more stable) decreases in proportion to young ice. It’s a sign the whole region is unstable.