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.

Life and the Planet – Part 1

23 05 2011

Life and the Planet meeting at the Geological Society of London

I recently attended the Life and the Planet meeting (May 5-6) held at Burlington House, home of the Geological Society of London, of which I am a fellow. In attendance were many of my friends and colleagues from the Gaia in Oxford meetings, including Jim and Sandy Lovelock, Lynn Margulis, Susan Canney, Tim Lenton, Andrew Watson, David Wilkinson, Anne and Mark Primavesi, and Bill Chaloner.

While the meeting had a Gaia theme, the program consisted of a number of speakers mainly from the geological sciences who are new to the discussion of Gaia. In general the speakers did a fair job of characterizing many of the dramatic shifts in earth’s history, such as the great oxygenation event, snowball earth, and the effects of the first plants on the planet, but many avoided mention of feedbacks, regulation, chaos, and complexity.

The one exception, of course, was the opening talk by James Lovelock. His keynote address was masterful, starting with a concise historical overview of Gaia theory for the many newcomers to the debate. He pointed out that the “atmosphere is almost entirely a biological product”. In his unapologetically alarmist voice he warned of “massively harmful climate change”, and suggested that climate change should mobilize science to geoengineer a fix. He then brought Gaia into the discussion of snowball earth by proposing a set of phytoplankton-driven ocean/atmosphere feedbacks involving sulfur pathways that could help drive the onset and termination of ice age conditions. Acknowledging ocean scientist Brian von Herzen in helping formulate this biotic ice age feedback, he stated “We have no notion if it offers a correct explanation but I put it to you as an example of the need for a whole science approach when seeking explanations of planetary scale phenomenon on a live planet like the Earth” (my bold). He then added, “This is especially true of the next catastrophe, the climate change we are now causing by the excessive excretion of CO2.” Read the rest of this entry »

The potential role of peatland dynamics in ice-age initiation

10 01 2010

As I mentioned in a previous post I am putting up some of my earlier work on feedback mechanisms by which the planet cools itself. This background will be useful in an upcoming post on planetary temperature regulation.

The potential role of peatland dynamics in ice-age initiation

by Lee F. Klinger, John A. Taylor, & Lars G. Franzen

Quaternary Research 45: 89-92 (1996)

Summary – Physical and chemical coupling of peatland vegetation, soils and landforms and atmosphere creates feedbacks which may be important in ice-age initiation. A box diffusion CO2 exchange model shows that a transient forcing of 500Gt C (the amount proposed to have accumulated in peatlands during the last interglacial-glacial transition) over 5000 yr results in a lowering of atmospheric CO2 by about 40 ppm. Proxy data indicate that a decrease in atmospheric CO2 may have occurred over the last 5000 years up to pre-industrial times, and the amount (~22 ppm lowering in 5000 yrs) is similar to that calculated from Holocene peatland expansion. These results suggest that models should consider the role of peatlands in ice-age initiation.

View the entire paper here.

In Fig. 2 (see below) we present evidence that prior to the industrial era atmospheric CO2 was undergoing a decline. We attribute the decline to large-scale landscape transformation involving the replacement of forests by peatlands. Peatlands store immense amounts of carbon and, as described in an earlier publication, are potentially powerful organs that help cool the planet.