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OAE - Natural Cycles Feedbacks, https://pmc.ncbi.nlm.nih…

- - - - move C back into long term storage
        
        with lower temp (due to GHG), slower circulation (THC)
        
        increased residence time
    - - INCREASE in pH instead of decrease
- - - - slow Global warming
        
        cooler atmosphere
        
        cooler oceans
        
        intake more CO2
        
        less degassing at warmer regions
      - lower emissivity/absorptivity of atmosphere
        
        less radiation absorbed and emitted back by atmosphere to surface
- - - - more PS CO2 intake
        
        more glucose produced
        
        biological pump more C into deep sea
  - - - reduced growth and reproduction
        
        https://onlinelibrary.wiley.com/doi/10.1111/j.1461-0248.2010.01518.x#b73
  - - - https://www.mdpi.com/2077-1312/8/10/821
        
        "higher water temperatures had a negative effect on the growth of most autotrophic phytoplankton groups/species"
        
        reversing ocean acidification would decrease CO2 conc and decrease temperature
- - - - move ph back to original
        
        more CO32-
        
        more CaCO3 can be formed
        
        aragonite (and calcite) organisms less at risk
        
        less HCO3-
        
        less CO2 and H2CO3
      - "However, seawater with slow air-sea gas exchange, in which alkalinity increases, consumes CO2 from the surrounding water without immediate replenishment from the atmosphere, which would increase seawater pH and saturation states and may impact marine biota (Meysman and Montserrat 2017; Montserrat et al. 2017). It may be possible to use this effect to ameliorate ocean acidification"
        
        https://www.ipcc.ch/report/ar6/wg3/downloads/report/IPCC_AR6_WGIII_FullReport.pdf
    - - reverse thermal expansion
        
        lower sea levels
    - - cooling surface water
        
        Atlantic Meridional Overturning Circulation speeds back up
        
        normal Gulf Stream (driven by subtropical gyre and AMOC)
        
        normal amount of heat and water transfer in Atlantic
        
        less stratification with deep ocean (density is more similar)
        
        more mixing
        
        top layer more re-oxygenised after materials decay
        
        more nutrient supply to surface layers
        
        phytoplankton growth
        
        https://www.nature.com/articles/nature06267
  - - - cooling atmosphere
        
        less ice sheets melt
        
        albedo feedback
        
        less algae growth
        
        reversing melt-elevation feedback?
        
        marine ice sheet instability - cooler water under ice shelf
        
        less melting
        
        reduce sloping inwards
        
        reduce further melting
        
        less permafrost melting
- - - - cooling
        
        less rainfall
        
        less weathering
        
        increase CO2
  - - - very long residence time
- - - - less soluble
        
        less dissolved CO2
        
        decrease pH
- - - - https://bg.copernicus.org/articles/22/499/2025/#section4
        
        "OAE will result is a rise in pH with adjustment of the DIC speciation towards bicarbonate and carbonate, followed by ingassing of CO2 to restore the equilibrium. If ingassing is restricted, the rise in pH will be accompanied by a draw-down in DIC if there is an excess of photosynthesis versus respiration."
        
        "unequilibrated OAE in coastal waters. In this scenario, discharge in the nearshore will likely be into strong lateral flow. Under these conditions, exposure to elevated pH would be relatively short until cumulative discharge of alkalinity raised the pH of the entire water body. The combination of dilution by transport and reaction of the alkalinity with CO2 (followed by CO2 invasion) would greatly reduce the timescale of exposure to elevated pH"
        
        "This study clearly shows that there are significant differences between the effects of transientand long-term exposure to elevated pH. There are significant changes in growth rates with chronic exposure to elevated pH that are consistent with reports from the literature but are not observed following transient exposure to the same range of high pH. If consistent results are found across taxa or in mixed assemblages, the estimates of threshold pH at which growth rates were reduced – which were all based on chronic exposure in pH drift or semicontinuous culture – are likely to overestimate the potential impact of OAE if the alkalinity is diluted on timescales of 10 min to 1–2 h following discharge into the receiving waters."