Scientific meeting on Gaia at the Geological Society of London – November 11, 2015

5 10 2015
Carlsbad caverns. Photo by Lee Klinger.

Carlsbad caverns. Photo by Lee Klinger.

On November 11, 2015 there will be a meeting entitled “Puzzle of Earth’s Uninterrupted Habitability” to be held at the Geological Society of London (GSL). This meeting will have a strong emphasis on Gaia theory and several prominent Gaian scholars will be speaking, including Tim Lenton, David Wilkinson, Toby Tyrrell, and David Schwartzman. As a Fellow of the GSL I have been invited to speak at this meeting. Here are the title and abstract of my talk:

Biological mediation of acidity and alkalinity: Does habitability require regulation of environmental pH?

Lee Klinger, Independent Scientist, Big Sur, CA USA

Abstract – Climatic cycles such as ice ages represent large excursions in global temperatures and are associated with significant changes in atmospheric CO2, non-sea salt sulfate, and dust, as recorded in ice cores. Ice age excursions in the pH of marine waters are predicted to result from the altered concentrations of CO2 in those waters. In addition, there are a number of biologically mediated processes affecting the pH of terrestrial and marine environments.

During interglacials terrestrial ecosystems are dominated by forests and grasslands that experience frequent disturbances, especially fire, which tends to alkalinize the soils. At the onset of glaciation higher latitude fire regimes subside and the forests become podzolized, with a corresponding decrease in soil pH. Many of these areas are eventually paludified, owing primarily to the acidifying and swamping effects of mosses and lichens, which eventually dominate the expanding peatlands. Mosses and lichens are known to stimulate silicate weathering rates to levels that could significantly reduce atmospheric CO2, and the cooling effects of peatlands are thought to play a role in ice age initiation. There is evidence that the production of iron-rich organic acids by peatlands greatly enhances phytoplankton blooms in adjacent coastal areas. Rainfall chemistry from the Pacific northwest points to the occurrence of biogenic acid rain likely originating from DMS and other biogenic sulfur compounds emitted by the phytoplankton. A feedback results through the nss-sulfate deposition enhancing the growth of mosses.

As ice ages progress and glaciers grow, dust levels in the atmosphere are also seen to rise. Much of this dust is due to an increase in glacial loess. The iron content of the dust stimulates marine productivity in open ocean areas. Oceanic inputs of iron from volcanic ash and glacial outwash are also seen to increase during glacial periods.

The culmination of the glacial period is defined by feedbacks involving the expansion of glaciers into areas formerly occupied by peatlands. The high mineral content of the glacial loess, along with episodes of volcanic ash would tend to alkalinize the terrestrial ecosystems and discourage the proliferation of mosses and other acidifying organisms.

Thus, the pH excursions in the ice age cycle may be related to the biogeochemical coupling of the iron and sulfur cycles. This coupling could have its roots in the Precambrian banded iron formations (BIFs), cyclic depositions of iron-rich minerals that are likely biogenic in origin. BIFs are seen to be closely associated with snowball earth conditions.





Acid rain in Big Sur – 2011-2012 season summary

3 02 2013
Big Sur Coast

Marine haze comprised largely of sulfate aerosols produced by ocean phytoplankton is a possible source of acidity in the rain in Big Sur. Photo by Lee Klinger.

I’ve been remiss in not posting this sooner. Here is the summary data for the  2011-2012 rain season in Big Sur. During the season we received a total of 25.49″ of rain, which is below the average of the previous four years (32.25”). The rainy season lasted for nearly 8 months, with the first rains arriving on October 4, 2011 and the last rains falling on May 27, 2012.

Rainfall from 29 events, totaling 25.13″, was measured for pH. The season volume-weighted average pH was 4.91 ± 0.16. This mean pH was higher than the average of the previous seasons (mean volume weighted pH 2007-2011 = 4.77).

Season length: October 4, 2011 to May 27, 2012

Total rainfall: 25.49″

Rainfall from 29 measured events: 25.13″

Mean volume-weighted pH (± s.d.): 4.91 ± 0.16

For summaries of previous years see “Acid rain in Big Sur 2010-2011 season summary“, “Acid rain in Big Sur 2009-2010 season summary”, and “Acid rain in Big Sur”.

The graph below shows the mean volume-weighted pH values recorded from Big Sur for the past 5 rain years, along with the mean volume-weighted pH values reported from six National Acid Deposition Program (NADP) sites along the Pacific coast, from southern California (Tanbark) to southeast Alaska (Juneau). Note that the NADP sites have data only through the 2010-2011 rain year. Data for the most recent rain year are not yet available from NADP.

2012 rain pH

Mean volume-weighted pH values of precipitation at six NADP sites and at Big Sur

This graph shows that the rainfall pH readings from Big Sur are significantly lower than those at the NADP sites near the Pacific coast. As I mentioned in last year’s summary, some of this difference is possibly due to the fact that the NADP sites report “lab pH” and the Big Sur readings are “field pH”. Typically the “lab pH” readings are higher (less acidic) than “field pH”. Another reason is that the Big Sur station is significantly closer to the Pacific Ocean than the NADP sites. If the Pacific Ocean is the source of much of the acidity, as I suspect, then the lower readings at Big Sur could be due to the closer proximity to the source of acidity.





Acid rain in Big Sur – December 2011

21 01 2012

Marine haze in Big Sur. Photo by Lee Klinger.

December 2011 was a dry month. I recorded only two precipitation events totaling 0.75″ of rain. Only one event provided an amount that could be measured for pH. That occurred on December 12 with a pH of 4.67, which is close to the mean pH of the 2010-2011 rainy season (pH = 4.66). See the table below for the December 2011 data:

Rainfall amount and pH recorded in Big Sur for December 2011

During the warm sunny days of December a thick marine haze developed that engulfed the region for many weeks (see photo above). This haze has been shown on other studies to be comprised largely of sulfate and organic aerosols, the precursors to biogenic (i.e. natural) acid rain.





Acid rain in Big Sur – November 2011

30 12 2011

Sunset at rain pH station in Big Sur. Photo by Lee Klinger.

After some respite in the acidity in October, the rain pH in Big Sur has returned to more typical acidic levels this past November. There were six rainfall events in November 2011, totaling 3.31″. Rainfall pH values ranged from 4.64 to 4.94 in November, considerably more acidic than the previous month which saw rainfall pH’s as high as 5.13. Below are the data for November: Read the rest of this entry »





Acid rain in Big Sur – October 2011

27 11 2011

Acid rainbow over Big Sur, October 2011. Photo by Lee Klinger.

The rainy season has started early again this year in Big Sur, with the first rains falling on October 3. October rainfall at my rain gauge (see station photo below) totaled 3.53”. Below are the pH readings. Three of the four readings are notable higher (less acidic) than usual here in Big Sur, though all the readings are more acidic than what is considered normal for unpolluted rainfall pH (~ 5.6). This is not meant to imply, however, that the acidity measured here in Big Sur is due to anthropogenic pollution. There is a distinct possibility that a portion of the acidity is coming from natural, oceanic sources. Still, no one knows for sure where the acidity in the Big Sur rain is coming from.

For summaries of acid rain readings from previous years see my previous posts. Read the rest of this entry »





Acid rain in Big Sur – 2010-2011 season summary

14 06 2011

[Update: Another late season storm moved through Big Sur yesterday (June 28) depositing 0.42″ of rain with a mean pH of 4.74. I’ve adjusted the seasonal rainfall data below. These new data have no effect on the overall mean weighted pH for the 20010-2011 rain season.]

The 2010-2011 rain season in Big Sur seems to be over, finally, after a late season June storm. This season we received a total of 32.66” 33.08″ of rain, which is very near the average of the previous three years (32.0”). The rainy season lasted for 8 full well over 8 months, with the first rains arriving on October 6, 2010 and the last rains falling on June 6, June 28, 2011.

Sun casting on the side of my home in Big Sur being dissolved by acid rain. Photo by Lee Klinger.

Rainfall from 36 37 events, totaling 23.04” 23.46″, was measured for pH. The season volume-weighted average pH was 4.66 ± 0.10. This mean pH was lower than the average of the previous seasons (mean volume weighted pH 2007-2010 = 4.78).

Season length: October 6, 2010 to June 6, June 28, 2011

Total rainfall: 32.66″ 33.08″

Measured rainfall from 36 37 events: 23.04” 23.46″

Mean volume-weighted pH (± s.d.): 4.66 ± 0.10

For summaries of previous years see “Acid rain in Big Sur 2009-2010 season summary” and “Acid rain in Big Sur”.

The graph below shows the mean volume-weighted pH values recorded from Big Sur for the past 5 rain years, along with the mean volume-weighted pH values reported from six National Acid Deposition Program (NADP) sites along the Pacific coast, from southern California (Tanbark) to southeast Alaska (Juneau). Note that the NADP sites have data only through the 2009-2010 rain year. Data for the most recent rain year are not yet available from NADP. Read the rest of this entry »





Acid rain in Big Sur – May 2011

6 06 2011

Acid rain falling on Big Sur. Photo by Lee Klinger.

It has been an unusually rainy spring here in Big Sur. We received 1.86″ of rain in May and have just had another full on winter storm here in the first week of June. I’ll be summarizing the 2010-2011 rain season data once it is clear the rainy season had ended.

The rains in May were notably acidic. There were five measurable rainfall events with pH values ranging between 4.46 to 4.63. The table below shows all the results for May 2011. Read the rest of this entry »