This quote is from the comprehensive booklet, 'Ocean Acidification: Questions Answered', published by The Ocean Acidification Reference User Group, a confederation of more than 160 marine scientists from across the globe.

As the headline 'the evil twin' suggests, ocean acidification (OA) is potentially as serious as predicted climate changes. This is because human-caused increases of CO2 in the atmosphere are projected to increase the acidity of the surface layers of the ocean by 150% before 2100. Only an immediate return to pre-industrial levels of CO2 in the atmosphere—an impossibility—could reverse the process of ocean acidification. OA is almost certain to produce a mass extinction event for life in the oceans with consequent impact on the food supplies for many land-based species, humans included.