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Discussion > Greening?

Meh, I see you and RR have already discussed this. Over time, replacement of CO2 has not kept pace with sequestration.

Oct 28, 2016 at 3:52 PM | Unregistered Commenterkim

If you are right, ACK, and if we've reached balance, 280 ppm may be the nadir. I suspect we don't know enough about the fluxes yet. I think there has been continuing lowering.

Nonetheless, raising the level in the atmosphere is a good.

Oct 28, 2016 at 4:00 PM | Unregistered Commenterkim

This is an interesting question, ACK; you are the geologist and have clearly thought about this before. Where is the proof that we have a good handle on the fluxes, which act over immense periods of time. Where is the evidence besides the IPCC, which couldn't possibly have a conflict of interest, could they?

Oct 28, 2016 at 4:13 PM | Unregistered Commenterkim

Kim. I don't think so. Let's take the Ordovician, a division of the Lower Palaeozoic. Lots of limestones in NorthAmerica (where I studied them), very few over most of Europe and most of those accumulated slowly and are rather thin. If we try to reconstruct their original extent we find that most of them have gone, most eroded away, some involved in subduction into the mantle or into deep parts of the crust, later to be involved in mountain building (a very thin Ordovician limestone occurs within the Scottish Dalradian metamorphic rocks of the Highlands). Much, perhaps most Ordovician limestones have been destroyed.

Certain periods in the past are characterized by net additions of geocarbon. The Carboniferous with abundant limestones, and coals, and the Cretaceous with abundant carbonates (chalks), coals and petroleum source rocks. Other times (like the present) are characterized by tall and still rising mountains (lots of weathering) and only small areas where modern shallow water carbonates are forming. So over geological time there is a great variation between net accumulation and net destruction of geocarbon.

Oct 28, 2016 at 5:33 PM | Unregistered CommenterACK

Kim. On certain parts of science, one of which is the carbon cycle, I implicitly trust the IPCC reports as displaying some of the finest summaries of their subject.

Oct 28, 2016 at 5:41 PM | Unregistered CommenterACK


Oct 28, 2016 at 5:48 PM | Registered CommenterMartin A


Oct 28, 2016 at 5:53 PM | Registered CommenterMartin A

Now look at Figure 1d, the trend probability distributions. The modes, the maximum probability values, are what I am looking at.

Both GIMMS and GLOBEMAP show no trend at all.(etc etc)
Oct 27, 2016 at 11:03 PM | Unregistered CommenterEntropic man

EM - I understand your motivation to discredit anything that suggests increased atmospheric CO2 may have benefits. But, unless you make a load of assumptions and then verify them, the mode of an estimated probability density function tells you nothing at all or, worse, will seriously mislead you.

For example, here is a discrete distribution of a random variable x. (Discrete for ease of understanding but the argument applies equally to continuous probability density functions)

x p(x)

0 0.1
1 0.05
2 0.05
3 0.05
4 0.05
5 0.05
6 0.05
7 0.05
8 0.05
9 0.05
10 0.05
11 0.05
12 0.05
13 0.05
14 0.05
15 0.05
16 0.05
17 0.05
18 0.05

The mode (x = 0) is the most probable value but, all the same, there is a probability of 90% that the value of the random variable will be greater than 0. So to say something like "The mode is equal to zero, so large values are unlikely" would be outright wrong.

Oct 28, 2016 at 6:12 PM | Registered CommenterMartin A

I don't particularly have a view on this, but it's an interesting subject, so I'm grateful to EM for starting this thread.

I followed the link, and hoped to find the full paper, so that I could read it in full, and see what I made of it, but unfortunately its paywalled. All I could find were the greening (or otherwise) maps/charts, and a summary of the main findings:

"Global environmental change is rapidly altering the dynamics of terrestrial vegetation, with consequences for the functioning of the Earth system and provision of ecosystem services. Yet how global vegetation is responding to the changing environment is not well established. Here we use three long-term satellite leaf area index (LAI) records and ten global ecosystem models to investigate four key drivers of LAI trends during 1982–2009. We show a persistent and widespread increase of growing season integrated LAI (greening) over 25% to 50% of the global vegetated area, whereas less than 4% of the globe shows decreasing LAI (browning). Factorial simulations with multiple global ecosystem models suggest that CO2 fertilization effects explain 70% of the observed greening trend, followed by nitrogen deposition (9%), climate change (8%) and land cover change (LCC) (4%). CO2 fertilization effects explain most of the greening trends in the tropics, whereas climate change resulted in greening of the high latitudes and the Tibetan Plateau. LCC contributed most to the regional greening observed in southeast China and the eastern United States. The regional effects of unexplained factors suggest that the next generation of ecosystem models will need to explore the impacts of forest demography, differences in regional management intensities for cropland and pastures, and other emerging productivity constraints such as phosphorus availability."

The summary seems to contradict EM's desire to rubbish Ridley and the whole greening argument ("Zhu et al is very weak evidence of greening. Goldany and Ridley are making a propoganda [sic] mountain out of a greening molehill.").

Maybe it is very weak evidence of greening, maybe it isn't, but it seems to me we all need rather more to go on than we have seen, before we can make such statements. I'm not inclined to pay to see the paper, but I would like to know what it says in detail, before commenting further.

Oct 28, 2016 at 7:42 PM | Unregistered CommenterMark Hodgson

Entropic man
I have no knowledge, as you specifically mention Australia I wondered if you did, or had references which I wouldn't be able to read at the moment.

Oct 28, 2016 at 9:01 PM | Unregistered CommenterSandyS

Thanks, Alan. Should I mention Dover?

Oct 28, 2016 at 9:12 PM | Unregistered Commenterkim

ACK, if we could subduct climate science, how long before it was forcibly rejected by Mother Earth and explosively ejected as a lava flow?

At least when it cooled it would have metamorphosed into something solid, dependable and reliable to build on.

Oct 28, 2016 at 11:36 PM | Unregistered Commentergolf charlie

If the current Greening continues, with extra rainfall thrown in for good measure, the UNESCO World Heritage site "Petra" in the Jordanian desert, may become habitable again, just as it used to be.

It will be terrible for the Jordanian Tourist Board.

Oct 28, 2016 at 11:57 PM | Unregistered Commentergolf charlie

Oct 29, 2016 at 1:21 AM | Unregistered Commentergolf charlie

golf charlie
That'll be science catching up with why farmers and gardeners take precautions against frost which can prevent plants ever budding at all. Plants use all sorts of triggers to start growth in the spring, but more the vast majority cold day or night isn't one of them. The same is true for insects, cold winters tend to reduce populations.

Next we'll learn that unseasonably warm/cold and dry/wet also has an impact on plants.

Oct 29, 2016 at 8:54 AM | Unregistered CommenterSandyS

Mark Hodgson. When you next come across a pay-walled paper you really want to read, contact the author identified by e-mail and request a PDF. If this request is accompanied by a commentary explaining your interest (especially if you refence a related paper) you will have established your bona fides. I can tell you there is nothing an author values more than to be contacted by someone outside of academia with a genuine interest in your work.

That's why CRU's reaction to McIntyre was so very odd, but then he was asking for data not a copy of a published paper.

Happy hunting!

Oct 29, 2016 at 9:00 AM | Unregistered CommenterACK

golfCharlie. Climate science probably would never be subducted - it's far too light weight. More likely it would be scraped off the descending plate to form a highly contorted accretionary wedge. Ultimately this will be raised, almost unrecognizable to form the cores of new mountains. Some might be caught up by rising magma to erupt as volcanic lavas and pyroclastic flows. Nothing recognizable from the original.

Oct 29, 2016 at 9:12 AM | Unregistered CommenterACK

Kim. Why would you want to mention Dover, what does he have to say about it?

Oct 29, 2016 at 9:16 AM | Unregistered CommenterACK

With Planet Earth now appearing more green when seen from space, are we now at greater risk from alien invasions, attracted by the natural fertility, or will bug eyed monsterss from outer space conclude that the planet, with semi intelligent lifeforms, is already doomed by the proliferation of Greens and their destructive thinking?

Oct 29, 2016 at 10:25 AM | Unregistered Commentergolf charlie

I see now you've already mentioned those chalk cliffs.

Instinctively I reject that unsequestration of carbon has reached balance with sequestration but it may be so. These are vast time scales, not completely understood, over which these processes act.

Nonetheless, raising the atmospheric level above 280 ppm is a great boon to the biome, and I stand by my prediction that a self-aware biome(that includes us) will prefer a higher level than the minimum at dynamic balance.

Oct 29, 2016 at 1:01 PM | Unregistered Commenterkim

Martin A

Why does everybody assume I am trying to fiddle the data? Is fiddling the data normal practice among sceptics?

I am familiar with the problem you describe.

For other readers, a symmetrical distribution has equal numbers of values on each side. The mode (the most frequent value) and the mean ( the average value) are the same.

The probability distributions in Zhu et al Figure 1d are not symmetrical. They are right-skewed,weighted towards the right. The mean has a larger value than the mode.

In such cases one can compare means or compare modes. Since I do not know the means, but could pull the modes off the graph, I compared the modes.

Climate sensitivity curves are also right-skewed. For example, see this guest post by Nic Lewis at Bishop Hill.

Nic Lewis is comparing different determinations of climate sensitivity using their modes. Martin, are you going to tell Mr Lewis he is wrong?

Oct 29, 2016 at 1:37 PM | Unregistered CommenterEntropic man

kim. It's long been known that plants have been on near starvation rations. I recall my father discussing this with me when I was at Junior School. There can be no doubt that the entire biota is benefiting from the CO2 increase, and will continue to do so.

Oct 29, 2016 at 1:43 PM | Unregistered CommenterACK


If you knew that the person requesting your paper or data was going to use it to craft a propoganda attack on your work, would you still be keen to give it to them?

Oct 29, 2016 at 1:43 PM | Unregistered CommenterEntropic man

EM 1:43 ACK may have his own response but ...

If the paper was sound science, based on reliable data, why would there be a problem? Just because a paper has passed climate science peer review, does not mean it is sound science based on reliable data.

You used the term "propaganda attack". Just because Climate Science now suffers from guilt and embarrassment due to perpetual failure, does not constitute confirmation that they are right. People are after climate science data due to the track record of lies and dishonesty.

Oct 29, 2016 at 2:02 PM | Unregistered Commentergolf charlie

Mark Hodgson. When you next come across a pay-walled paper you really want to read, contact the author identified by e-mail and request a PDF.

Oct 29, 2016 at 9:00 AM | Unregistered CommenterACK

Alan, many times I have politely requested a pdf of a climate science paper, explaining that I do not have access to library facilities nor a budget to access papers.

Richard Betts of the Met Office has sent me stuff I requested from him. But, apart from RB, I only once received a reply. In that case, the author, notwithstanding what I had said, simply advised me to download the paper for myself.

My impression is that this reluctance to reply to such requests is a purely climate science thing.

Oct 29, 2016 at 2:12 PM | Registered CommenterMartin A