Dear Frank I want to get the math of this correct. The claim is that the oceans have changed pH from 8.2 to 8.1, that this is (at least in part or totally) caused by human emissions of CO2, right? And further that this represents a '30% increase in acidity'.
The method described asserts that it is a logarithmic scale and that the 30% and the term 'acidity' are appropriate. I would like to put this in perspective. If the 'acidity' rose 15,800% then the oceans would be Neutral, neither acidic nor alkaline using conventional terminology. As oceans vary from about 8.4 to 7.8 that is a natural variation of '400%', using the same definition as is applied in the case of '30%'. In the case of rain, which has a CO2 content of over 10,000 ppm it is '50,000% more acidic' than ocean water at pH 8.2. In fact rain really is acidic. Seems to me that if '30%' is catastrophic the EPA should ban rainfall with immediate effect. It is obviously wrecking the ocean. Regards Crispin >From BB9900 -----Original Message----- From: "Frank Shields" <[email protected]> Sender: "Stoves" <[email protected]> Date: Fri, 5 Jul 2013 10:29:22 To: 'Discussion of biomass cooking stoves'<[email protected]> Reply-To: Discussion of biomass cooking stoves <[email protected]> Subject: Re: [Stoves] on ocean acidification This is a very good topic and related to Stoves to the point of noting the difference of a measure of Biochar pH value and alkalinity value. The pH is really not that important as many think it is. It's the alkalinity that is important. Having a water with a pH of 8.3 takes little acid to lower the pH but toss in a chunk of lime and the pH is still 8.3 but you will need to add acid until all the lime is dissolved before the pH goes down. So pH is just a reading. Alkalinity (or neutralizing value) is a measure of the amount of buffering holding that pH. We report this as CaCO3 equivalent units so it can be compared to adding limestone to a soil. We boil a Biochar sample in 100 mls of 0.5N HCl to dissolve all the carbonates and oxides in the sample then back titrate using NaOH to determine the amount buffering (or neutralizing value) the sample has. Much more useful. Frank Thanks Frank Shields BioChar Division Control Laboratories, Inc. 42 Hangar Way Watsonville, CE 95076 (831) 724-5422 tel (81) 724-3188 fax [email protected] www.controllabs.com -----Original Message----- From: Stoves [mailto:[email protected]] On Behalf Of [email protected] Sent: Thursday, July 04, 2013 11:47 PM To: Discussion of biomass cooking stoves Subject: Re: [Stoves] on ocean acidification On Thu, 04 Jul 2013 23:21:20 -0600,Mark Bigland-Pritchard / Low Energy Design Ltd <[email protected]> wrote: >I wouldn't normally want to post off-topic, but I think it is necessary >that an error be corrected before this thread is put to sleep. Mark I'm happy with your correction explaining pH. As we generally do use pH to denote acidity rather than hydrogen ions I think it is misleading to then say a 30% increase in hydrogen ion activity equates to a 30% change in acidity. I think change in ocean ecology due to this small change in pH is a very serious concern but please all of you take the discussion elsewhere and stick to stove issues. AJH _______________________________________________ Stoves mailing list to Send a Message to the list, use the email address [email protected] to UNSUBSCRIBE or Change your List Settings use the web page http://lists.bioenergylists.org/mailman/listinfo/stoves_lists.bioenergylists .org for more Biomass Cooking Stoves, News and Information see our web site: http://stoves.bioenergylists.org/ _______________________________________________ Stoves mailing list to Send a Message to the list, use the email address [email protected] to UNSUBSCRIBE or Change your List Settings use the web page http://lists.bioenergylists.org/mailman/listinfo/stoves_lists.bioenergylists.org for more Biomass Cooking Stoves, News and Information see our web site: http://stoves.bioenergylists.org/ _______________________________________________ Stoves mailing list to Send a Message to the list, use the email address [email protected] to UNSUBSCRIBE or Change your List Settings use the web page http://lists.bioenergylists.org/mailman/listinfo/stoves_lists.bioenergylists.org for more Biomass Cooking Stoves, News and Information see our web site: http://stoves.bioenergylists.org/
