No growth stimulation of Canada's boreal forest under half-century of combined warming and CO2 fertilization
Considerable evidence exists that current global temperatures are higher than at any time during the past millennium. However, the long-term impacts of rising temperatures and associated shifts in the hydrological cycle on the productivity of ecosystems remain poorly understood for mid to high northern latitudes. Here, we quantify species-specific spatiotemporal variability in terrestrial aboveground biomass stem growth across Canada's boreal forests from 1950 to the present. We use 873 newly developed tree-ring chronologies from Canada's National Forest Inventory, representing an unprecedented degree of sampling standardization for a large-scale dendrochronological study. We find significant regional- and species-related trends in growth, but the positive and negative trends compensate each other to yield no strong overall trend in forest growth when averaged across the Canadian boreal forest.
Via @ClimateAudit -- if warming doesnt stimulate northern forest growth, dendro reconstructions of past temperature by Mann, Briffa etc are worthless. No surprise
...and how much of the temperature record cited by Manbearpig in AIT, etc. was from dendrochronology? That all gets tossed (and imho should never have been considered anywhere near reliable--too many significant variables besides temperature).
Sounds like the variables are out of control and research proves nothing. That doesn't spare us from a report. Maybe the reason nothing has changed is that nothing was actually changed.
"Climate Change" may well be the biggest and most urgent problem facing mankind today. If we don't get this scam fixed we could destroy our economy and lose our liberty.
That my friend is the point of the scam. ;-)
This study admits that growth responses didn't show the dramatic increases observed in controlled experiments (for example: http://www.co2science.org/articles/V1/N4/B6.php ), "Our study suggests that elevated atmospheric CO2 is a large-scale, but subtle phenomenon and the detection of a CO2 effect requires a large spatial covering where local confounding factors and interannual variability in climate and disturbances average each other out and allow the CO2-related effects to be detected...."
Good science isn't exciting and disappoints those looking for the instant gratification of reinforcement of preconceived notions. Greenhouses with enhanced CO2 produce enhanced growth and that is a well known phenomenon. I have seen it along side the controls and planted the enhanced outcome.
RightOn TheTooner. Govts will run out of revenue tools well before the climate changes. Then what? The law of the jungle?
If we don't get a course correction real soon, we will hit the brick wall at full throttle!
From the abstract:
"Growth–climate relationships bring evidence of an intensification of the impacts of hydroclimatic variability on growth late in the 20th century, in parallel with the rapid rise of summer temperature."
Did you catch that? Nothing about CO2. "hydroclimatic variability" = moisture, rain, WATER.
Much of my introductory course in basic ecology (or was it introductory botany) was spent discussing the principle of "limiting factors". In short and simplified, this is the principle that an organism (plant in this case) will respond negatively to a deficit of any one of its basic needs for growth.
As a simple example, give a plant abundant light and proper soil, etc but limit water and you will have little growth ...... water is a limiting factor.
"Our analyses suggest that soil moisture has been an important driver of tree growth in boreal Canada since the mid-20th century: 12 of the 19 species studied clearly show dependence on this variable."
and
"The sensitivity of Canada’s boreal forest to soil moisture during the second half of the 20th century is striking and in agreement with findings from US forests (31). Projections of future climatic drying pose a major concern for Canada’s boreal forest ecosystems (9), especially in the western Prairie Provinces where forest distribution and ecosystem functioning are strongly moisture limited (32)."
and
"In many Canadian areas, the trends in forest growth were consistent with the directional trend in soil moisture."
I'm unsure where in Canada moisture has been abundant and where it has been lacking or even what the summer temperatures have been. But on summer temperatures, I'm reasonably confident that they have not been so high as to be a limiting factor.
Overall, it's an interesting study but I wouldn't say it concludes anything new or unusual ABOUT THE EFFECTS OF CO2 on plant growth.
P.S. I just skimmed the article. Like most people I have neither the time nor the interest to dissect and ponder the whole thing.
These reports are purposely written in language that quickly turns of the average reader. They are very often quite lengthy. Hence the average Joe/ Jane will trust the "experts." and not "waste their time trying to figure it out. Hey "The Voice" or "X Factor" etc is on, let's watch that!
That is because trees don't make good thermometers. Everyone knows this, yet the Alarmists continue to try to use them. Trees do a much better job at recording rainfall and sunlight than they do temperature.
That is because trees don't make good thermometers. Everyone knows this, yet the Alarmists continue to try to use them. Trees do a much better job at recording rainfall and sunlight than they do temperature.
Didn't we already know this? Isn't this why Mann had to splice thermometers onto dendro to get the hockey stick? (Hide the Decline and all that)
The original bristlecone pine tree ring study, the one Mann used to infer temperatures, specifically said it should NOT be used to infer temperatures.
What % of Forestry "scientists" will still advocate for higher taxes and less freedom while promoting the scam at the expense of their science and integrity ?
I'm guessing 80%.
Selected science.
What kind of growth response did the computers models predict?
It'll be another big dead fish face slap.
Those of us who have worked around greenhouses where seedlings were grown with enhanced CO2 know the results and there is also an excellent database at CO2science.org where controlled experiments have been documented for a significant number of tree species including those mentioned in this study. The results all show various levels of enhanced growth and more efficient uptakes of water with given CO2 increased concentrations. The authors of this study know they didn't get the "expected" results and it's likely because they haven't accounted for all the variables in an uncontrolled environment.
This is my fifth attempt at trying to get through the SDA filters, just in case it makes it!
I was a "practicing" professional forester in BC up until the last year when I changed my status to "retired" in part due to my disgust at the level of rent-seeking and buy-in to CAGW hysteria. The Canadian Forestry Service (connected with this study), a federal research agency has bought in big time as have all provincial forest services and academia. Your number of 80% is likely low. Forest scientist aren't so much into the tax / climate control farce as they are into the hubris of selecting species and other management techniques for a "warmer" future forest. Don't ask what happens when we possibly get a cooler future forest in the mean time.
"Considerable evidence exists that current global temperatures are higher than at any time during the past millennium." And herein the rub. That "considerable evidence" is based on the very tree ring analysis which this paper now effectively debunks.
"trees don't make good thermometers"
This probably explains my failure last week to measure my core body temperature with a tree.
A significant greening of the world has occurred with higher CO2 in the atmosphere. It's not only the CO2 fertilization factor, but as-it-happens increased CO2 levels allow plants to require less water. Links to this have been posted over the past month or so. Anyone interested can go look in the archives.
Matt Ridley: global-warming-versus-global-greening is one of the best presentations on this subject.
http://www.thegwpf.org/matt-ridley-global-warming-versus-global-greening/
Red Neck translation-
Its gonna snow ass deep in Canada this winter.
I wonder why the obvious never seems obvious to so many?
I may not spell this correctly but the anti-transpiration effect has been known for decades. I read about it in depth at least twenty years ago. the global warmists just ignore anything that does not fit their template.
Matt Ridley "I am not saying the main cause of that increase (CO2) is not the burning of fossil fuels; it is."
Really! No one knows how much the burning of fossil fuels adds to the increase in CO2 and how much is 'natural'. His statement reduces the credibility of his presentation.
Paraphrasing one comment out of context only shows that the point of Ridley's talk was completely missed.