Really ought to have someone else explain it as chemistry was always my weakest subject, but the reaction here is well known, well documented, and not at all controversial. I simply don't have the chemistry to tell you at what atmospheric CO2 concentration will effect a body of water with a given buffering capacity and bioload mix.
At the moment is very hard to answer that kind of questions since there is really no data set for the ocean pH and since the ocean acts as a buffer solution and pH is logarithmic it will take considerable CO2 to acidify the oceans.
I've seen people saying that man made CO2 is responsible by the change of 0.02 units per decade, but there is really no tool to accurately measure ocean pH.
There is even a prize to design an ocean pH sensor.
http://oceanhealth.xprize.org/competition-details/overview
"OVERVIEW
The Challenge: Improve Our Understanding of Ocean Acidification
The Wendy Schmidt Ocean Health XPRIZE is a $2 million global competition that challenges teams of engineers, scientists and innovators from all over the world to create pH sensor technology that will affordably, accurately and efficiently measure ocean chemistry from its shallowest waters… to its deepest depths.
There are two prize purses available (teams may compete for, and win, both purses):
A. $1,000,000 Accuracy award – Performance focused ($750,000 First Place, $250,000 Second Place): To the teams that navigate the entire competition to produce the most accurate, stable and precise pH sensors under a variety of tests.
B. $1,000,000 Affordability award – Cost and Use focused ($750,000 First Place, $250,000 Second Place): To the teams that produce the least expensive, easy-to-use, accurate, stable, and precise pH sensors under a variety of tests.
The Need for the Prize
Problem
Our ocean are currently in the midst of a silent crisis. Rising levels of atmospheric carbon are resulting in higher levels of acidity. The potential biological, ecological, biogeochemical and societal implications are staggering. The absorption of human CO2 emissions is already having a profound impact on ocean chemistry, impacting the health of shellfish, fisheries, coral reefs, other ecosystems and our very survival.
The Market Failure
While ocean acidification is well documented in a few temperate ocean waters, little is known in high latitudes, coastal areas and the deep sea, and most current pH sensor technologies are too costly, imprecise, or unstable to allow for sufficient knowledge on the state of ocean acidification.
Solution
Breakthrough sensors are urgently needed for scientists, managers and industry to turn the tide on ocean acidification and begin healing our ocean. A competition to incentivize the creation of these sensors for the study and monitoring of ocean acidification’s impact on marine ecosystems and ocean health will drive industry forward by providing the data needed to take action and produce results."
Ocean acidification and ocean temperature rising have basically no data and no instruments to acquire that data reliably, so lots of theory and few facts.
http://www.nbcnews.com/science/2-mi...-tools-monitor-ocean-acidification-8C11097122
""It is only in the last decade where scientists have begun to study ocean acidification, so our knowledge is really limited still," Paul Bunje, a senior director with the X Prize Foundation who is the lead scientist behind the ocean health competition, told NBC News.
"But we do know that we don't know enough, and we don't have the tools needed to even begin to measure it sufficiently — much less to begin to respond, to adapt to it, to implement local policies that might allow ocean acidification to be less harmful," he said.
Just as the $10 million Ansari X Prize spurred innovation in the private space industry, the Ocean Health X Prize aims to jump-start new business ventures dedicated to sensors that can dramatically improve understanding of the oceans, including acidification.
The open ocean is acidifying at about .02 pH units per decade, according to according to Richard Feeley, a marine scientist and leading researcher on ocean acidification at NOAA's Pacific Marine Environmental Laboratory in Seattle. "That means that you have to have an instrument that you can rely on to be both precise and accurate for a very, very long period of time, so that you can actually see that signal," he told NBC News."