London - A new paper just published in Science summarizes the projected impacts of climate change on the world’s oceans, and consequently on humans and our economy. The study concludes that global warming beyond the international limit of 2°C above pre-industrial temperatures would pose serious threats to marine ecosystems and their millions of human dependents. It builds on the consensus science published by the Intergovernmental Panel on Climate Change last year.  The oceans have absorbed over 90% of the excess heat and 28% of the carbon pollution generated by human consumption of fossil fuels. As the authors of the paper note, in many regions, the ocean plays an important role in the livelihood and food supply of human populations. The ocean represents more than 90% of the Earth’s habitable space, hosts 25% of eukaryotic species, provides 11% of global animal protein consumed by humans, protects coastlines, and more. The study considers human impacts on the world’s oceans under two different scenarios. The first is a business-as-usual high fossil fuel consumption scenario (called RCP8.5 in the latest IPCC report), and the second is a scenario in which humans take immediate serious steps to curb fossil fuel consumption (called RCP2.6). Between now and 2100, RCP8.5 involves 6 times more global carbon pollution emitted by humans than RCP2.6. In summary, the carbon that we emit today will change the Earth System irreversibly for many generations to come. The ocean’s content of carbon, acidity, and heat as well as sea level will continue to increase long after atmospheric CO2 is stabilized. These irreversible changes increase with increasing emissions, underscoring the urgency of near-term carbon emission reduction if ocean warming and acidification are to be kept at moderate levels. (FA)