Marine species subjected to high CO2 extremes – 8,891 to 95,000 ppm – in their natural environments may not be adversely affected. They may even “thrive”.
Earlier this year we highlighted a study that says coral reefs “thrive” near seafloor volcanic vents where CO2 concentrations reach 60,000 to 95,000 ppm.
Image Source: PHYS.ORG
Urchins basking in volcanic vent streams of 8,891 ppm CO2 and daily CO2 variations of more than 2,000 ppm as well as day-to-day pH fluctuations ranging from 6.9 (“acidification”) to 8.1…grow more than two times faster than nearby control (stable 394 ppm CO2, 8.1 pH) urchins (Uthicke et al., 2016).
Image Source: Uthicke et al., 2016
According to a new study, corals “were observed to persist within acidified [<7 U] waters”, with pH lows reaching as low as 6.5 (Enochs et al., 2020). This effectively means corals can endure any doomsday “ocean acidification” scenario allegedly linked to human fossil fuel burning.