An illustration of "tipping point" effects; reduction of sea-ice leads to even faster take-up of CO2 by the ocean, leading to accelerated acidification.
Acidity 30% higher than pre-industrial levels. "Even if CO2 emissions stopped today, it would take tens of thousands of years for the sea chemistry to revert to pre-industrial levels".
Tarrel - there's much more to it than this crummy BBC report of a research study riddled with optimism bias describes. One of the minor warming feedback effects can be foreseen in the decline of the oceanic carbon sink due to both raised water temperature and raised acidity, leaving a larger fraction of annual CO2 outputs in the atmosphere.
The statement that it will take tens of thousands of years to return acidity to normal is potentially nonsense - it ignores the presence of humans. To successfully control global warming, one of the three necessary main forms of action is Carbon Recovery, which will have to be used to cleanse the atmosphere of anthro-CO2 pollution.
At present CO2 passes into seawater when the airborne concentration is at least 7ppmv higher than that in the water. Peaking the airborne concentration will thus halt the net oceanic anthro-carbon sink, and intentionally reducing airborne CO2 will cause the oceans to outgas CO2 into the atmosphere. While this will extend the period for which the Carbon Recovery program must run, it will in effect also cleanse the oceans' surface waters of their anthro-CO2 burden, thereby ending their acidification.
Using a maximum of the potential for terrestrial biomass feedstocks (without diverting farmland or natural forests) including native coppice afforestation, water hyacinth, and urban & agricultural wastes for the Carbon Recovery program, it will, by my calculation, take around 30 years to reach full flow, and will then need around 80 years of operation to achieve its objective of restoring the pre-industrial CO2 level of 280 ppmv.
This implies that, given the accompanying Emissions Control & Albedo Restoration programs, marine acidification can be peaked around 2040 and fully terminated early next century.
Biff - you're mistaken to think my comment is optimistic - it lays out the requirement for action on acidification within the limits of our biomass capacities under rational constraints, and does so as objectively as possible.
I'd fully agree that achieving that level of action will require emulating creatures with rather more backbone than jellyfish (meaning no offence to jellyfish of course) - but the problem of acidification is plainly far from intractable.
It is the international politics of inaction that are problematic, though the natural dynamics we're unleashing would, if left unaddressed, certainly outrun any human control given time. Those international politics we've briefly discussed previously, with you taking the position that it is mere conspiracy theory to suggest that the US intransigence over the requisite climate treaty is intentionally facing China with the rising threat of crop failures, shortages and civil unrest leading to regime change.
Being unable to subscribe to the conventional conspiracy theory that the avarice of the US fossil lobby - that provides just 8% of US GDP - is allowed to dictate US foreign policy to the extreme detriment of US interests, I must stick with the analysis of a covert US foreign policy of a 'Brinkmanship of Inaction' with China.
I wonder if you've considered how, if US policy was only accidentally hitting China's food security, it would probably be the first empire in history to be destabilizing its rival's food supply by accident ?
I suspect that China is far more resilient than the US in terms of food supply. They have, within living memory, much experience of dealing with famine and even today a large proportion of food consumed in cities is actually produced within the cities. The Americans are not allowed to grow veg on their front lawns.
But that's getting away from ocean acidification, which I regard as a hard problem.
Billhook wrote:It is the international politics of inaction that are problematic
The nail firmly hammered home.
What to do, Lewis? What are your suggestions?
I experience pleasure and pains, and pursue goals in service of them, so I cannot reasonably deny the right of other sentient agents to do the same - Steven Pinker
Hey, long time no, ermm, read Keela. Welcome back.
I experience pleasure and pains, and pursue goals in service of them, so I cannot reasonably deny the right of other sentient agents to do the same - Steven Pinker
Anyone else wondering whether ocean acidification, and the recent collapse of a load of chalk-type cliffs on the South Coast, are at all Related? I think we should be told, etc...
