Here’s a surprise. The growth of trees in Britain appears to correlate to cosmic ray intensity. University of Edinburgh researchers have found that trees are growing faster when high levels of cosmic radiation arrive from space. This may also correlate to the Interplanetary Magnetic Field which tends to modulate Galactic Cosmic Rays. The discover lends credence to Svensmark’s work on GCR to cloud cover correlation by demonstrating yet another tangible effect.
The researchers made the discovery studying how growth rings of spruce trees changed over the past half a century.
Here’s the kicker: the variation in cosmic rays affected the tree growth more than changes in temperature or precipitation.
ABSTRACT (link)
- Here, we investigated the interannual variation in the growth rings formed by Sitka spruce (Picea sitchensis) trees in northern Britain (55°N, 3°W) over the period 1961–2005 in an attempt to disentangle the influence of atmospheric variables acting at different times of year.
- Annual growth rings, measured along the north radius of freshly cut (frozen) tree discs and climatological data recorded at an adjacent site were used in the study. Correlations were based on Pearson product–moment correlation coefficients between the annual growth anomaly and these climatic and atmospheric factors.
- Rather weak correlations between these variables and growth were found. However, there was a consistent and statistically significant relationship between growth of the trees and the flux density of galactic cosmic radiation. Moreover, there was an underlying periodicity in growth, with four minima since 1961, resembling the period cycle of galactic cosmic radiation.
- We discuss the hypotheses that might explain this correlation: the tendency of galactic cosmic radiation to produce cloud condensation nuclei, which in turn increases the diffuse component of solar radiation, and thus increases the photosynthesis of the forest canopy.
The BBC also covers this in an article, here is an excerpt:
By Matt Walker
Editor, Earth News
The growth of British trees appears to follow a cosmic pattern, with trees growing faster when high levels of cosmic radiation arrive from space.
Researchers made the discovery studying how growth rings of spruce trees have varied over the past half a century.
As yet, they cannot explain the pattern, but variation in cosmic rays impacted tree growth more than changes in temperature or precipitation.
The study is published in the scientific journal New Phytologist.
“We were originally interested in a different topic, the climatological factors influencing forest growth,” says Ms Sigrid Dengel a postgraduate researcher at the Institute of Atmospheric and Environmental Science at the University of Edinburgh.
“The relation of the rings to the solar cycle was much stronger than to any climatological factors “Sigrid Dengel University of Edinburgh
To do this, Ms Dengel and University of Edinburgh colleagues Mr Dominik Aeby and Professor John Grace obtained slices of spruce tree trunks.
These had been freshly-felled from the Forest of Ae in Dumfriesshire, Scotland, by Forest Research, the research branch of the UK’s Forestry Commission.
The trees had been planted in 1953 and felled in 2006.
The researchers froze the trunk slices, to prevent the wood shrinking, then scanned them on to a computer and used software to count the number and width of the growth rings.
As the trees aged, they showed a usual decline in growth.
However, during a number of years, the trees’ growth also particularly slowed. These years correlated with periods when a relatively low level of cosmic rays reached the Earth’s surface.
When the intensity of cosmic rays reaching the Earth’s surface was higher, the rate of tree growth was faster.
Read the entire BBC report here
Kerry Rodgers (10:52:33) “[…] correlation and causation?”
Everyone knows this — throwing this in peoples’ face does not advance the discussion.
Here is another study supporting the idea that cloudiness actually enhances plant photosynthesis
In a research article published in March 28, 2003 Science magazine titled
“Response of a Deciduous Forest to the Mount Pinatubo Eruption: Enhanced Photosynthesis” (http://www.as.wvu.edu/biology/bio463/Gu%20et%20al%202003.pdf ) authors, Lianhong Gu, et al, contend that:
“Volcanic aerosols from the 1991 Mount Pinatubo eruption greatly increased
diffuse radiation worldwide for the following 2 years. We estimated that this
increase in diffuse radiation alone enhanced noontime photosynthesis of a
deciduous forest by 23% in 1992 and 8% in 1993 under cloudless conditions.
This finding indicates that the aerosol-induced increase in diffuse radiation by
the volcano enhanced the terrestrial carbon sink and contributed to the temporary
decline in the growth rate of atmospheric carbon dioxide after the
eruption.”
Furthermore, they state:
“There is evidence indicating that Mount Pinatubo aerosols increased high
cloudiness, particularly in the middle latitudes. Variations in cloudiness can influence the global carbon cycle, because clouds are effective producers of diffuse radiation and can also change many meteorological variables that affect plant activities.
The observation that forest ecosystems often absorb more CO2 under cloudy
conditions than under cloudless conditions supports this idea.”
“Around noontime at the Harvard Forest site, diffuse radiation increases with cloud cover and reaches maximum when cloud cover is about 60%. Because of this, Harvard Forest photosynthesis also increases with cloud cover, with a peak at about 50% cloud cover (SOM text; fig. S8). Improved moisture condition and reduced solar heating may further enhance carbon uptake under cloudy conditions. If Mount Pinatubo aerosols increased global cloudiness moderately (without overly reducing global solar radiation), this would be an additional pathway for global terrestrial photosynthesis to be enhanced by the eruption, further contributing to a larger terrestrial carbon sink and the decline in the observed growth rate of atmospheric CO2. Our study suggests that long-term trends and interannual variability in cloudiness and aerosol concentrations may play important roles in the dynamics of the global carbon cycle.”
In other words, if Svensmark’s theory is correct, we don’t need a huge volcanic explosion to produce diffuse radiation to enhance plant growth, as all we need is a little more cloudiness caused by an increase in atmospheric aerosols production due to more cosmic rays reaching the Earth’s atmosphere.
Another factor in this is forest density. Tree ring increase is a lateral increase in the size of a tree. Growth is three dimensional and in a crowded forest there is a race to the top of the canopy. Have a look at the commercial crowding in http://news.bbc.co.uk/earth/hi/earth_news/newsid_8311000/8311373.stm (middle photo) to see this effect where growth is directed vertically for commercial reasons at expense of lateral growth.
Therefore forest crowding is another factor in tree ring width.
Stephen Brown (above),interesting comments about greenhouse modification increasing the fruit bearing properties of tomatoes and potatoes. Our Tomato growing season in Canberra is short and one suggested method of bringing on the fruit rapidly is to pull the bush out of the ground and immediately replant it. This seems to shock the plant into thinking Armageddon has come,plant vegetative growth stops and all energy goes into the reproductive mode. I have suggested before that this cycle is enacted by all plants, with vegetative growth rate being restricted by the need to reproduce.
Another tree ring size factor.
Boy, this is complex.
It seems to me that what’s needed in this research area (and many others) are the equivalent of double blind medical studies. The trees should be selected at random, etc. Does anyone know if this philosophy has been discussed and/or formulated?
supercritical (07:12:27)
On chirality and polarisation, I make the obvious speculation that direct sunlight in high latitudes is heavily polarised, but cloud cover will diffuse the light and so depolarise it, and that may be why photosynthesis seems to be faster in cloudy conditions.
Maybe plants like depolarised light, so high latitude tree-rings could be a proxy for variation in polarisation of sunlight … such as cloud cover, local magnetic field, auroral effects, & co. etc. ,
The most probable reason efficiency ,where nature has around 2.7g/yr to evolve a very efficient mechanism fo energy transfer.At the molecular or quantum level this efficiency is close to 100%. in the light harvesting centers to the reaction centers a nm distance.
In addition the changes or process are very fast in the region of picosecond so temperature has little difference at 77k or 300k in energy transfer .
There is an interesting article here .
http://www.lbl.gov/Science-Articles/Archive/PBD-quantum-secrets.html
There is this study out there :
Biomarker Response to Galactic Cosmic Ray-Induced NOx And The Methane Greenhouse Effect in The Atmosphere of An Earth-Like Planet Orbiting An M Dwarf
http://www.spaceref.com/news/viewsr.nl.html?pid=23857
Though it does look to be model based so GIGO rules could apply.
Tree ring data from a single exotic tree plantation shows a very weak correlation with cosmic rays.
Nope, can’t get too excited about that.
Interesting to note, 15,000 years ago there were no trees in Scotland, nary a one. Trees wouldn’t grow there at all, due to the abundant ice. Whatever the recent microscopic perturbations in tree growth that researchers claim to have detected there, they are nothing compared to the massive vegetative changes of the aberrant Holocene.
Thankfully, Most Scots are all PC-hot and PC-bothered that trees will grow at all in their country, since by all rights Mother Nature prefers that landscape to be frozen solid and devoid of life of any kind.
I quite agree. We need massive global cooling to sterilize Scotland by freezing it solid in conformance with the Intent of Mother Nature, as best as we mere mortals can understand Her. Kumbaya.
Quality control please. Has anybody here ever hear of autocorrelation? Or does that only matter if you don’t like the paper. Dengel et al. is a case study in what happens when you ignore autocorrelation.
just wondering if this discussion is still active…
I just read all the comments (out of curiousity) and though I contribute…
– Sitka spruce is a native to Alaska, so the cooler the better, the moister the better too, I guess. Also, if its raining its cloudy but it does not always rain when its cloudy….