Saturday, September 29, 2007

The Trouble with Lichen

“This is not the age of reason, this is the age of flummery, and the day of the devious approach. Reason’s gone into the backrooms where it works to devise means by which people can be induced to emote in the desired direction.”John Wyndham, J. (1960), The Trouble With Lichen.

There is a popular belief that the ozone layer has been "saved". Not so, says Joe Farman, one of the scientists who discovered the Antarctic ozone "hole" - even as the Montreal Protocol celebrates its 20th birthday, much remains to be done. Reports the BBC

The mid-70s saw the publication of several seminal scientific papers identifying the possibility of ozone-destroying chain reactions in the stratosphere.

Ozone depletion in early spring over Antarctica had been reported in the journal Nature in May 1985, much more severe than any prediction, and confirmed by Nasa in October 1985.


Lets ask the question what if it has been always there,as evidenced by the biosphere in responding to spring ozone losses!

There are few methodologies to show suitable proxies to ascertain the UV levels and variation ,Nitric acid in ice cores is one,but the resolution is coarse and shows only multidecadeal variation signals .Another method is to view the response of the biosphere to changes in UV.

As we have discussed here and here the changes and effects of UV flux is the precursor mechanism for the oscillations in CO2 absorption and emission from the biosphere and hence changes in the atmospheric levels.

The ability of biological species to adapt to adverse environments is one of the paradoxes of Ecological science.

How the exclusion of some “players” from the” marketplace” will allow for smaller players to dominate the market due to enhanced adaptability.

Changes to the ozone levels and UV penetration are cyclical over the solar cycles from the 27 day rotation, the 11 year cycle ,the Gleissberg cycle and longer orbital parameters.

Solar variability is observed on three main time scales: solar rotation (27-day), solar cycle (11year) and the Grand Minima time scale. The magnitude of the variability progressively increases from the short to long scales. Earth's climate responses are now found on all these scales. The most recognized are the responses to solar irradiance variations. These variations strongly depend on wavelength rising from 0.1% per solar cycle in total irradiance (mostly infrared-optical range) to 10% in UV and 100% per solar cycle in X-ray range. The variations in the total irradiance produce a small global effect. More substantial is the effect of solar UV variability on large-scale climate patterns. These patterns are naturally excited in the Earth's atmosphere as deviations (anomalies) from its mean state.

How does the distribution of UVB, UVA, and photosynthetically active radiation vary on sensitive surfaces within the biosphere in the agricultural and forest canopies over the growing season? Plants have widely varying sensitivity to solar UV radiation. This can result in shifts in the competitive advantage of one plant species over another and consequently composition and health of both manages ecosystems.

The so-called "season responders" are species with an opportunistic strategy growing only under optimal light conditions mainly in summer, whereas the "season anticipators", grow and reproduce in winter and spring.

This suggests that the microalgae have adapted to predicting not only the early spring photosynthetically active radiation, but also high spring flux of UV due to ozone loss as seen by the levels of melanin pigmentation

Rozema et al in a number of physical experiments have shown proofs that the responses to changes in UV by the biosphere in both Antarctic algae, and various Lichen is equivalent to a 15% change in Stratospheric ozone.

The growth of the lower land organisms studied, i.e. the lichens Cladina portentosa, Cladina foliacaea and Cladonia arbuscula, and the club moss Lycopodiumannotinum, was not significantly reduced when grown under elevated UV-B radiation (simulating 15% ozone depletion).

Most of the plant species and plant groups tested were well adapted to the enhanced UV-B simulating a 15% depletion of stratospheric ozone.

Thus the evolution of plant and animal life on Earth seems partly to have been governed by the changing UV climate, seen today in the array of different life forms, field habitats, and protective strategies.

Journal of Photochemistry and Photobiology B: Biology 66 (2002) 2–12

The role of UV-B radiation in aquatic and terrestrial ecosystems—an
experimental and functional analysis of the evolution of UV-absorbing
compounds

3 Comments:

Blogger Erl said...

Maksimovich
Two comments and a question:
Re UVB radiation:
The extent of very short wave radiation penetration is greatest in the tropics as revealed at http://www.temis.nl/uvradiation/world_uvi.html
There are to me obvious water vapour effects on the distribution including an interesting one east of the Antarctic peninsula.

Re Cosmic ray penetration and the strength of the heliomagnetic sheet:
The strength of the suns magnetic field relates to the influence of the solar wind on the upper atmosphere and the penetrability of the tropical atmosphere to all forms of solar radiation. Svensmark’s cloud effect relies on exactly the same mechanism that I suggest is responsible for the El Nino oscillation. However, I am suggesting a fluctuation in the amount of solar radiation reaching the surface. Both mechanisms work in the same direction.

In the south west of WA where I live the vegetation has to withstand lots of UVB and the tannin and quercetin levels in the skins of my grapes varies accordingly. This assists to make long lived wines relying on natural preservatives rather than having to rely on sulphur dioxide. With the La Nina developing the tropical and subtropical atmosphere has become less penetrable to short wave radiation and all the plants here are having a great time. The forest is revegetating with a lighter shade of green. Of course its partly rainfall but rainfall is never limiting in winter and spring anyway.

How are you going with the paper at: http://happs.com.au/downloaders/Chance_of_rain.pdf

Consider: If the heat absorbing capacity of a medium that lies between a very warm body A and a much cooler body B increases, the medium warms. If the medium has the capacity to lose warmth to the space between A and B there will be a net reduction in the flow of energy to B, causing the surface of B to cool.

erlathapps.com.au

Erl

4:10 PM  
Blogger Erl said...

Maksimovich
Two comments and a question:
Re UVB radiation:
The extent of very short wave radiation penetration is greatest in the tropics as revealed at http://www.temis.nl/uvradiation/world_uvi.html
There are to me obvious water vapour effects on the distribution including an interesting one east of the Antarctic peninsula.

Re Cosmic ray penetration and the strength of the heliomagnetic sheet:
The strength of the suns magnetic field relates to the influence of the solar wind on the upper atmosphere and the penetrability of the tropical atmosphere to all forms of solar radiation. Svensmark’s cloud effect relies on exactly the same mechanism that I suggest is responsible for the El Nino oscillation. However, I am suggesting a fluctuation in the amount of solar radiation reaching the surface. Both mechanisms work in the same direction.

In the south west of WA where I live the vegetation has to withstand lots of UVB and the tannin and quercetin levels in the skins of my grapes varies accordingly. This assists to make long lived wines relying on natural preservatives rather than having to rely on sulphur dioxide. With the La Nina developing the tropical and subtropical atmosphere has become less penetrable to short wave radiation and all the plants here are having a great time. The forest is revegetating with a lighter shade of green. Of course its partly rainfall but rainfall is never limiting in winter and spring anyway.

How are you going with the paper at: http://happs.com.au/downloaders/Chance_of_rain.pdf

Consider: If the heat absorbing capacity of a medium that lies between a very warm body A and a much cooler body B increases, the medium warms. If the medium has the capacity to lose warmth to the space between A and B there will be a net reduction in the flow of energy to B, causing the surface of B to cool.

erlathapps.com.au

Erl

4:11 PM  
Blogger maksimovich said...

Dear Erl

1 The extent of very short wave radiation penetration is greatest in the tropics

Correct as we see in Wuttke et al.
http://www.rsc.org/Publishing/Journals/PP/article.asp?doi=b617602j

Changes in the upper atmosphere water content can be observed in nox-ch4 uv photolysis with were ch4 is the primary source of water vapour.

Replace gcr with high energy particles for the precurser energy mechanism and you are not to far from the mark.

Rather then Svensmark to eliminate controversies real or imagined by " climate modelers with vested interests"(tenure) it is easier to use Mansurov et al., 1974,Turco,Yu Tinsley etc.

The optical atmospheric transparency is quite correct M. G. Ogurtsov covers this well in "Secular Variation in Aerosol Transparency of the Atmosphere
as the Possible Link between Long-Term Variations in Solar Activity and Climate"

you are also on the right path with colour changes in phyto tissues,if you search for xanthrophylls you will see the evolutionary histological defense strategy odf adaption.The lighter pigmentation seen in leafs at midsummer can be either mg deficiency or "photon overload" ie full up.

Re your paper I will finish reading after the symposium I have posted on.

Regards

2:04 AM  

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