"Shane Gallagher
2.3
9 July 2012 at 10:00 am
Okay – I am going to assume you are simply mis-informed…. In order to create pasture out of what was once forest you have to either burn it down or chop it down. Mostly it was burnt – carbon goes into atmosphere. Then you plow the fields – more carbon escapes into the atmosphere as there is a lot of carbon trapped in the soil that is released when you plow it. Also you get run-off into water and that helps release more carbon. Then you put cows on the pasture land who essentially convert a large amount of the grass into methane. Now methane has a greenhouse effect 25 times that of CO2. So you chop down trees that are soaking up CO2 and storing it in the ground and replace them with Methane creating cows you have a net increase in our greenhouse gas emmsions.
Got it? This is basic chemistry… not that complicated really.
53 comments:
A mature forest is carbon neutral neither adding or removing any more atmospheric CO2, for a forest to be a net carbon sink it needs to be actively regenerating or harvested in a sustainable way and that carbon stored in floor boards or other timber.
Forest is definitely preferable to unsustainable farming practices though, no doubt about it, but it is possible to farm in a way where root recycling is adding to the carbon content of the soil.
Whether the modern dairy industry is really interested in anything other than mining the soil of carbon with lime, lime, and more lime due to very acidic urea fertiliser is another matter.
A mixed model of land use is the only sustainable option long term, unfortunately the modern dairy industry seems about as far away from that as is possible to get.
"A mature forest..."
I wonder, Shunda, if there's more to it than the wood alone. I reckon that vast amounts of carbon is stored in the soil under a forest through the impot of squillions of tiny critters that live and die there. Plus, the leafage that falls an becomes integrated into the soil as carbon, not lost to the air.
What do you reckon?
import
In order for it to be a net carbon sink it must be less 'forest' than a mature forest and by implication much of it's carbon would be in the wrong place so we should have no qualm with mature forests
So you are asking our current farmers to pay for when the forests were removed generations ago?
Also your correspondent misses some real basic chemistry. Farmers are net carbon fixers. Carbon is taken from the atmosphere and exported off farms in the form of meat, milk or wool.
But hey, don't let some minor details like facts get in the way of your religion.
Paranormal
I think there is an equilibrium that eventually develops that includes all those critters Robert, the rotting of which will always release CO2 to the atmosphere.
But as Bio said, any forest that was cleared has released most of it's carbon back into the atmosphere, so this in no way diminishes the importance of retaining forest cover. It also has an important role in retaining topsoil so the carbon cycle can continue.
I think the message here is that timber is an extremely "green" building material when it comes from a sustainably managed source, anything we build out of timber not only directly stores carbon, it removes all the CO2 needed to produce alternative materials like steel.
In this regard, engineering solutions involving the clever use of timber are probably the way of a sustainable future.
That's why I think we should investigate the sustainable use of NZ timbers such as Beech.
The situation that best fits a net natural carbon sink would be certain types of wetlands and peat bogs. This is effectively the creation of new coal, and could add weight to the importance of retaining such areas.
Unfortunately these wetlands are just as at risk from agricultural development as forests were or are.
Enough of the 'religion' slighting, paranormal. It makes you sound bitter and twisted. Argue the facts, if you must argue at all.
You supposition that anyonme is asking 'farmers to pay for forests removed historically', is trite. No one is. It's called a straw man, paranormal, and wastes our time with the asking. You ought to know better.
How can you possibly claim that 'farmers are net carbon fixers'? That's just daft and transparently wrong in the examples you give - meat, for example, is not a carbon store (unless it remains frozen) - it well be eaten and converted, in part, to methane etc. Milk too, Wool, to, though it takes longer.
Those 'minor details, wrongfully put by you, wouldn't 'get in the way' of anyone's 'religion', paranormal. It's such a insubstantial claim.
Shunda - I think you are not right (polite, eh!). Certain micro-organisms in the soil capture and bind carbonic gases, preventing them from rising into the atmosphere. I'm arguing that it's not just the timber that holds carbon in a forest.
It's not an equilibrium that is created, but an expanding store of carbon, especially where the forest is managed by humans, as is my prescription for the future health of the planet.
I guess I am thinking of an ancient forest that has existed for thousands of years which reaches an equilibrium of bugs, rot, and replacement growth. It probably takes a while though, for example, the Podocarp forests in Westland probably sequester carbon for thousands of years before they reach that equilibrium.
The obvious evidence of atmospheric carbon being stored in the earth is peat, coal, and possibly limestone, but even then, this seems to require other forces such as plate tectonics to complete the process.
Have had a look at that web site. RG you must be desperate in believing that is 'excellent debate!.
The heading says it all - A lot of hot air from the majority of the commenters. Psycho Milt sure gave the watermelons a run for the money.
"Agricultures emissions from belching livestock are quite different to the emissions from car exhaust and gas
fired or coal burning power stations. The difference is that agricultural carbon emissions are sustainable and have no impact on the atmosphere because they do not result in an increase of carbon in the atmosphere whatsoever; where as the other sources of methane emissions do result in an increase to the carbon content of the atmosphere."
"Not one molecule of extra methane or carbon gas is produced from a cow eating grass."
HT - Pastoral Farming
Nonsense, Sally. Grass grown here in Southland does so because it is fed with urea which is made from natural gas. That gas, like the 'car exhausts' you cite, originates underground as stored carbon.The urea converts to grass, the cow eats the grass and converts some of it to methane. Your Pastoral farming quote is demonstrably wrong. New Zealand farmers are importing and releasing huge amounts of carbon into the atmosphere as a direct result of farming cows.
If one is to consider the entire farming operation then it well proves that modern Agriculture practises are corbon emitters. The urea that RG has pointed has pointed to, the animals themselves, the many associated vehicles in and around farming, ie motor bikes, tractors, utes, cars, and the many trucks involved. Most urea is shipped here and you want to see the size of their motors - ironicly, the system that is being used to clean up the vehicle emmissions today (SCR systems) uses urea as its main ingredient. It works very well to.
That's correct, Towack, though as farmers quickly point out, they pay the same as every one else for their fuel, transport etc. emissions. It's the belching that they are being granted gratis by Key. Those belches, I'm arguing, originate underground where they were contained. Cows release them into the atmosphere. Gwynne Dyer's Opinion piece in today's Southland Times was very interesting, wasn't it.
I dont get the rag so did not see it, but I, like the cows tend to belch a lot after reading anything Gwynne writes.
I will be interested to see the results of our community boards plan to ban smoking in Rivertons parks. I would have thought there were plenty of other things for them to talk about during the meetings - guess the agenda is getting a little empty. Best Mr Procter leave Bluff and shift to Riverton - that would liven up the meetings........what a plonker
My muppet was asking me whether I support banning smoking in playgrounds. I said I didn't. You?
If the afore-mentioned plonker did move to Riverton, I swear our family would up-sticks and join your little community...my partner wants to already.
We could be neighbours Towey!
*whispers - but Suz, he parks his wife on the street!
Before you shift Suz you better read my profile and see if you can get past the town boundry.....
And as for the smoking thing, 1st - I never believe in making laws that cannot be enforced, they are pointless.
2 - This by law would not change a thing - it is a nod towards the pc brigade.
Best you and I, and Suz when she arrives, give the local board some decent things to get their teeth into.
Like sponsoring a yacht race into Riverton, then having the V8's race around the foreshore and then build a stadium over the estuary. And if they are still quiet after that how about a Chinese garden.
How about a Babylon style hanging garden, quick, do it before Tony Kokshorn mayor of Greymouth does!
"Hanging garden", Suz?
You've seen my 'hanging tree' post, obviously.
Towack - the cellphone calls whilst driving ban? Same pc brigade at work?
Ohhhhhh, yes!
And it's 'local bored', Towack - you've seen 'em in action (inaction).
Meant Shunda. Hard to tell you two apart and now that you're morphing into Towack, Suz, confusion reigns!)
I call bullshit on you again RG.
It was in the article you quote that your correspondent suggests he wants to ping farmers for the deforestation. I merely asked a question to raise the absurdity of that notion.
In what way will wool be released back to the atmosphere? Similarly with meat and milk used as building blocks in the food chain. Farnmers are net carbon fixers just as foresters are.
Your science is suspect to say the least - hence the religion analogy. You stick to your faith. You give IV2 a hard time for his faith. Why do you get so touchy when your faith based rubbish is pointed out to you.
Paranormal
Tony Kokshorn was my Rugby League coach way back when he was a car salesman......used to play for Marist - being the good Dooly that I am, not!
As for cell phones when driving, I dont think you can put it in the same conversation - I drive for a living and have seen to many close calls and also results, plus it can be, and is policed.
I would put it in the same line as Rivertons ban on camping, so many signs, yet so many campers...
paranormal - nt going to address the urea aspect then? Thought you'd dodge that one. Stored gas, spread on paddock, becomes grass, gets eaten, burp! - methane!
Come on, para. have a go at it at least.
Cellphone use, policed?
Ha ha ha!
Good one.
The incidence of cellphone use while driving has risen sharply in Southland over the past year, Towack, according to the Southland Times. Policed, maybe, but effectively policed, nah.
No point in having it if it can't be enforced eh!
I dont really understand where you are coming from RG, I know people who have been ticketed for yakking, it is surely an issue, esp those texting whilst driving - I see it all the time.
Plus I know people who have been ticketed - only a sucker would ever use newspaper stories to back them up -must go though as sending this from my iphone as I drive home
Yeah, Toawack - I know someone who was on the benefit but got a job so welfare-crisis is over in NZ!
Hooray!
Well that's good news Robert, I am surprised you didn't put up a separate post!!
I'll do a double when I've solved the unemployment issue.
RG. your logic is quite distorted you have made big assumptions that all grass is grown using urea which of course it is not.
RG, you actually have admitted that that it is only the CO2 produced from the manufacture of urea that is the problem, not the CH4 the cow produces.
Urea an d other nitrogen fertileisers only forms a very minor part of total livestock emissions. The price of their greenhouse effect will be incorporated into the price of the fertiliser.
Two thirds of our livestock emissions suppposedly come from methane and the other third from naturally produced nitrous oxide. I say supposedly quite intentionally. It takes a carbon atom to make a methane molecule. That carbon atom comes out of the grass which originally took it out of a carbon dioxide molecule that it took from the atmosphere. After an average of nine years that methane molecule will revert to a carbon dioxide molecule. This results in a full cycle and no change in the composition of the atmospheric gases occurred so no climate change or global warming has occured.
It is only by increasing livestock numbers that methane concentrations can increase in the atmosphere. If the total number of farmed animals in the whole world were to double there would only be a temperature increase of 0.01 degrees. Read that carefully. The temperature would increase by one one hundredth of a degree.
Tragically the whole climate change debate has been hijacked by misinformation being spread by those with no understanding of basic science.If we have more carbon dioxide inthe atmosphere plants will grow better thyan they do now. Almost all plants are currently suffering from too little carbon dioxide in the atmosphere. As soon as I hear someone calling carbon dioxide a pollutant I konw I am listening to somone who has been brainwashed or someone who is lying.
RG To say urea converts to grass is nonsense, the nitrogen provides the protein needed to create the cells in the grass using CO2 from the air.
So it helps promote grass growth and therefore a greater removal of CO2 from the atmosphere, but the carbon atom in the methane of the belching cow is sourced from the atmosphere not the underground store. That was released earlier. Therefore no net increase from the animal.
If global warming is happening it is not being caused by livestock biological emissions. No scientific link exists between these emissions and any increase in the atmospheric concentration of any greenhouse gas.
It is deliberate misinformation from the Greens that biological emissions need to be included in our ETS because international consumers demand it.
No other country has or intends putting a price on these emissions, so they are hardly likely to demand we do.
Disengenuos Labour claims farmers are receiving a subsidy. This utter rubbish.
No money is taken from a taxpayer and paid to anyone, because biological emissions are not due to enter the ETS until 2015 and until then, there is no cost to these emissions.
Almost all plants are currently suffering from too little carbon dioxide in the atmosphere. As soon as I hear someone calling carbon dioxide a pollutant I konw I am listening to somone who has been brainwashed or someone who is lying.
The plants are suffering? I think I'm listening to someone that's been brainwashed! ;)
So it helps promote grass growth and therefore a greater removal of CO2 from the atmosphere, but the carbon atom in the methane of the belching cow is sourced from the atmosphere not the underground store. That was released earlier. Therefore no net increase from the animal.
I'm not so sure you have that correct Sally.
Intensive dairying is reliant on external inputs to the natural grass growing cycle, and because energy can neither be created nor destroyed, the energy being placed into the system will be released in other forms including methane and co2. So I believe that Robert is correct in assuming that we are effectively using cows as little methane factories and turning at least some of those 'inputs' into greenhouse gasses. You can't add energy to the land from an external source and then suggest there is no net gain in emissions, the process of digesting grass means at least some of that energy is being converted to methane.
Nicely reasoned, Shunda.
Sally - I see the sort of arguer you are: an extrapolater-to-suit-your-own-ends, that sort. You say:
"RG. your logic is quite distorted you have made big assumptions that all grass is grown using urea which of course it is not."
Pish! I've not said all grass. You seized upon a claim from your own head and assigned it to me. I've watched your sort of argument unfold before - it goes nowhere except around and around the arguers own head.
"RG, you actually have admitted that that it is only the CO2 produced from the manufacture of urea that is the problem, not the CH4 the cow produces."
Again, you've seized upon an imaginary foe and have proceeded to defeat it. Well done! No connection to reality though. Stick to what I have said, not what you hope I've said, if you want to make any progress with the argument (you do want to make progress with it, don't you?)
Oh, Sally!
"No money is taken from a taxpayer and paid to anyone, because biological emissions are not due to enter the ETS until 2015 and until then, there is no cost to these emissions."
How self defeating this argument of yours! You, Sally, as a taxpayer, are paying now toward the cost of NZ's total assessed emissions. That is, the calculation was made of how much we emit, including from agriculture and we, as a country, have been paying that 'penalty'. You have, Sally, been paying for it and will continue to pay for it. Farmers were to have taken over the payment for their share of total, the amount that is attributed to emissions from their animals etc. but have been granted immunity by National, so that the taxpayer has to continue to shoulder the full amount. Get it?
"If global warming is happening it is not being caused by livestock biological emissions. No scientific link exists between these emissions and any increase in the atmospheric concentration of any greenhouse gas."
No scientific link exists... oh, Sally.
Contraptions designed to measure animal belches have been used here in NZ for some time now, proving that animals emit methane and CO2 into the atmosphere. Clearly, animals add to the atmospheric load of greenhouse gases. Animals don't 'suck it back in' and exude oxygen in it's place, as plants do, so it's plants and algae that you should look to to see if the balance is being achieved. How are our global forests looking, Sally? On the increase to counter the increase in gaseos emissions from vehicles, factories and pastoral animals? Answer on the back of a self-addressed envelope please.
Emissions are increasing. The 'greenhouse effect' isn't a marketing tool, it's an easily-proven phenomenon.
Neil, Neil...
"Urea and other nitrogen fertileisers only forms a very minor part of total livestock emissions."
(See, Sally? Neil agrees urea contributes to livestock emissions.)
"The price of their greenhouse effect will be incorporated into the price of the fertiliser."
Are you saying, Neil, that there is a greenhouse tax on urea? At what point is that extracted and to whom is it paid? This is news to me.
"Two thirds of our livestock emissions suppposedly come from methane and the other third from naturally produced nitrous oxide."
Your 'naturally-produced nitrous oxide' refers to urine from the cow, for example. That urine would not have been produced in such volume, without the addition of urea, which as we know, originates underground as a carbon store, safely sequestered, not being released into the atmosphere as a gas. farming does that. Takes it from underground, puts it through a plant, an animal and out into the atmosphere, where it adds to the atmospheric gas-load.
"I say supposedly quite intentionally. It takes a carbon atom to make a methane molecule. That carbon atom comes out of the grass which originally took it out of a carbon dioxide molecule that it took from the atmosphere."
You seem to be forgetting about the addition of urea, Neil. That must be part of an honest assessment, surely? "After an average of nine years that methane molecule will revert to a carbon dioxide molecule." CO2 is a greenhouse gas. You've described a process whereby more co2 than was previously in the atmosphere, now floats about in it, given that urea has added its contribution.
"This results in a full cycle and no change in the composition of the atmospheric gases occurred so no climate change or global warming has occured."
Quite wrong, as I've described. How can you ignore that urea contribution, Neil?
"It is only by increasing livestock numbers that methane concentrations can increase in the atmosphere. If the total number of farmed animals in the whole world were to double there would only be a temperature increase of 0.01 degrees. Read that carefully. The temperature would increase by one one hundredth of a degree."
Wrong again.Neil. If the total number of farmed animals in the whole world were to double, so to would the fossil-fuel inputs into pasture stimulation, and therefore the contribution to greenhouse gas emissions, so to would the amount of land that is not already in agriculture, that is, land that is carbon positive or carbon neutral; forests, swamps, wetrland etc, thus we would lose the beneficial effects on the atmosphere those environments have. Your science, Neil, with all due respect, is full'a holes!
"Tragically the whole climate change debate has been hijacked by misinformation being spread by those with no understanding of basic science."
Seems to be the case here, Neil :-)
"If we have more carbon dioxide in the atmosphere plants will grow better thyan they do now. Almost all plants are currently suffering from too little carbon dioxide in the atmosphere."
Shunda covered this claim elegantly :-)
" As soon as I hear someone calling carbon dioxide a pollutant..."
Have you heard someone claim this, Neil? Or are you making it up to suit your prejudice?
"...I konw I am listening to somone who has been brainwashed or someone who is lying."
So far, the only one using the word "pollutant", has been you, Neil.
What are we to make of that?
Ok RG how about those farmers that don't use Urea. It's been said on this blog numerous times that farmers are not all the same.
You're still avoiding the fact that at their core farmers are harvesting CO2. Have a look at the economics. At the farm gate the carbon inputs are priced higher per unit than the carbon outputs of a farm. For a farm to be profitable they must be net collectors and exporters of carbon.
Mind you that is still based on the misconstrued assumption that CO2 is not the life gas that it is.
Doesn't matter how often the flaws are pointed out the new religion prevails.
Paranormal
(Robert - on a thin client, said)
Paranormal - you're an ossified denier, so I'll have to couch my language to try to penetrate your plugged ears...
Not all farmers use urea, I agree. I'm not claiming they do. Those who aren't contributing to the greenhouse gas load should make their case to the tax collectors. Are you confident that they aren't applying some other previously sequestered carbon in its place though?
Some will be clean; the organic farmers, the bioliogical farmers, the biodynamic farmers. Their efforts should certainly be considered.
Farmers are harvesting CO2?
From the atmosphere, yes. From underground where it's sequesterd as well, as we've already covered. Harvesting and releasing into the atmosphere. Ploughing too, released stored carbon into the atmosphere. Forsets are rarely plougghed. Likewise swamps, if left to their own devices. Farming releases huge amounts of carbon into the air, where another practice might release none.
Co2 is a 'life gas'?
Not if you're trapped in a room that's entirely filled with it, it's not! You are playing with words, but anyone can do that. I can do that.
You are not, as you seem to believe, pointing out flaws. The discussion here seems to me to be science based, albeit amateur, whereas you consistantly claim it's religious. You have a curious obsession with the religious - were you brought up in a Brethren household, paranormal? Scientologist? Church of the Latter Day Saints?
Stick to the facts and we'll increase our understanding. Revert to your petty slights (Liarbour, anyone?) and you'll remain stuck in ignorance :-)
Sally,
Those pastoral farming guys don't know what they're talking about. The problem with cows (or their bacteria actually) is that they turn carbon from C02 into methane, which, as the OP says, traps heat about 25x more strongly than the C02 (actually a lot more than than, but it breaks down over time, so 25x is a life-adjusted number) so is a problem.
This is, as Rob said, basic physics but that's not enough to stop most "skeptics". Consider this though, if it is as easy as those clowns think it is to make a case that our biological emissions (most of our carbon footprint!) shouldn't be counted against us, don't you think the hundreds of policy experts and negotiators we send to meeting to lower our kyoto liability might have spotted this get out of jail free card?
Robert
Nitrogen fertiliser will be charged according to the amount of N in them. The fertiliser manufacturer will add it to the selling price and buy credits to cover it. Currently this will be from 2015, but I presume that will be delayed along with livestock emissions.
You are absolutely wrong to say that urea leads to methane being emitted. Urea has only one carbon atom and as the urea breaks down in the soil this is released as carbon dioxide. The nitrogen in the urea, which is the reason it is used by some farmers, is used for plant protein which in turn becomes animal protein. The source of all carbon released by an animal, be it carbon dioxide in the air it breathes out or in the methane it belches originally came from carbon dioxide the plant 'breathed in' from the atmosphere.
Applying urea overcomes a nitrogen deficiency. This allows more grass to grow and more carbon dioxide to be taken out of the atmosphere.
Our livestock emissions are deemed to be about one third nitrous oxide before allowing for nitrogen fertiliser. I do ot use urea, yet if livestock emissions come into the ETS about a third of my emissions costs will be from nitrous oxide. As I explained above, those that do use nitrogen fertiliser will pay an additional charge for that.
Your knowledge of methane is very incomplete. You mention swamps and wetlands being carbon positive or carbon neutral. Swamps and wetlands produce copious quantities of methane. The common name for methane is, afterall, swamp gas. It has been estinmated (it can't be calculated because nobody did the necessary measurements first) that the swamps and wetlands that farmers have drained produced more methane than the animals we now farm.
Even a pine forest produces methane and tropical rain forests produce even greater amounts. Wet, waterlogged soils also release methane.
I am stunned you have never heard people refer to carbon dioxide as pollution. Why, the Australians were even going to call their ETS the 'Carbon Pollution Reduction Scheme'.
In talking about the doubling of livestock I was only considering the methane component. It was also not a serious suggestion. It was merely to demonstarte that livestock are not causing a problem. Are you aware that the world's rice paddies produce more methane than the world's livestock?
If plants are put in an environment that has twice as much carbon dioxide their growth rate will improve by 30%. This means their current growth is being restricted compared to its potential. It was on this basis I used the word 'suffering'. I mean it in the same context that if we are put into a rarified atmosphere that is low in oxygen we 'suffer' in that our energy is sapped and we can not move as fast, we tire easily etc.
You are correct that ploughing removers soils carbon. But there is more carbon stored under healthy permanent pasture than there is under a pine forest.
"You are absolutely wrong to say that urea leads to methane being emitted."
Neil. Urea stimulates greater than normal plant growth. Those plants are eaten by cows who create methane relative to the amount of grass they have eaten. Therefore, the application of urea increases the amount of methane released. That the carbon came from the air is immaterial to my argument. The problem is, as David Winter explains, that methane is a far worse gas, warming-wise, than CO2. It exists for a much shorter time, but creates much more warming before it changes state to CO2.
As to your "pollutant" claim, I was stating that commenters here in this discussion haven't made the claim that Co2 is a pollutant. I have heard mention of it befroe today, but usually from people like yourself, arguingthat it isn't, rather than anyone claiming that it is. Don't be "stunned thatI'd never heard people refer to carbon dioxide as pollution", I didn't make that claim. It's a non-starter for me, but 'your lot' seem to like making an issue of it.You are stretching your argument to say that the Australians are doing it - as you wrote, they call their scheme, 'Carbon Pollution Reduction Scheme',not, 'CO2 Pollution..."
Your swamp claims are poorly supported as well. I know there are waterbodies of those sorts that emit methane but I've read papers that differentiate those that do the opposite. I won't/can't argue the details, as I haven't gone into swamps/bogs/quagmires/wetlands in any depth, so would be winging it, as I believe you are, simply claiming as you do, that swamps are bad emitters of methane.
"
If plants are put in an environment that has twice as much carbon dioxide their growth rate will improve by 30%. This means their current growth is being restricted compared to its potential. It was on this basis I used the word 'suffering'"
Presumably, if plants are put into an environment that has half as much carbon dioxide, their growth rate will decrease by some percentage. This could mean that or plants presently are thriving, rather than suffering, as you claim. Lucky things.
You say 'livestock is not causing the problem', and I'm not one to blame the cow. It's those who create cow-country and stock it with cows who are responsible for the amounts of greenhouse gases that rise from that operation.
Robert
This is just a quick reply as I do not have time tonight for a full one.
The urea does allow greater plant growth, but all that does is accelerate the cycling of carbon dioxide through methane back to carbon dioxide. If by using urea the farmer increases the number of cows there will be a one off increase in the amount of methane in the atmosphere until a new equilibrium is reached. But it does not follow that all the extra grass grown produces methane. The amount of methane produced varies with the quality of the feed, with high quality feed producing less methane. Methane is produced when bacteria break down cellulose. Low quality stalky pasture has more cellulose and produces more methane. Lush grass produces less. Some of the research being done at present is to quantuify this.
The word 'Carbon' in the Australian Carbon Pollution Reduction Scheme clearly infers carbon dioxide as that is the primary gas being targeted. It is very common, but mislesading for people, especially politicians, to refer to carbon dioxide reductions as the need to reduce carbon emissions. I strongly disagree that it is 'our side' that use this term the most. I shall find you some examples when I get a chance.
That swamps and wetlands produce large amounts of methane is well documented and I shall dig out some figures etc when I have the chance.
If we halved the amount of carbon dioxide in the atmosphere from the current approximately 400 parts per million most plants would die. Again I will come back with some figures to back this up.
If we halve the amount of C02 in the atmosphere...
has anyone suggested we should? If we multiply the number of dairy cows in Southland by 100, the environment would collapse over night...
Methane, Neil, if you keep adding it to the atmosphere at rate, well see serious effects very soon. It doesn't become 'part of the cycle' if there's more and more new methane emitting from increased numbers of cows. The effect of having new methane in the atmosphere does not equal that of C02. Extra cows, extra pastures, more vigorous pasture, fewer forsts, a Co2-saturated ocean - can't see why you're not a little alarmed, Neil. And we're not even looking at nitrates in ort ground and surface water, Southland's un-spoken-of problem. Cows, they're buggers of things :-)
Robert
You made the statement about plant growth rate decreasing in an environment with only half the amount of carbon dioxide. I was merely pointing out the growth rate would not simply decrease. It would stop and they would die. However I believe 180 parts per million is the limit of growth so they may not quite die, though some more sensitive species would. They would perform like plants that are under serious water stress. Growth would be negligible. They would be more vulnerable to disease and pests etc. But there is an organisation that calls itself 350.org that wants to reduce carbon dioxide levels back to 350 parts per million. It has a branch here in New Zealand.
Methane is a more powerful greenhouse gas than carbon dioxide. But it is far less simple than saying it is 21 times more powerful, as it is defined under the Kyoto commitment period, or 25 as it will be from 2013. For starters this is not a precise figure. That is why the value is being changed. It could be as low as 19 or as high as 31 for a period of 100 years.
But why do we choose this arbitrary period of 100 years. Methane breaks down after less than ten years. According to Mr Flannnery, an Australian climate change expert, carbon dioxide lasts at least 1000 years. Wouldn’t a fair comparison point be mid way between the two? That would lower the value for methane significantly. But Global Warming Potentials (GWP), which is what the above are, are not the only way to compare gases.
Another one is called Global Temperature Potentials and measures the amount of warming at a given future time. For 100 years time methane would be likely to be 6.9 under this regime with a possible range of 3.9 to 13.9.
GWPs are based on the same weight of gas. This is fine if you are comparing a kg of methane that has leaked out of a natural gas pipeline with a kg of carbon dioxide. But if you are comparing a kg of methane from an animal or rice paddy with carbon dioxide you need to make an important adjustment. As explained previously these methane molecules can only be made by first extracting a carbon dioxide molecule from the atmosphere. Allowance has to be made for this removal. A carbon dioxide molecule is 2.75 times as heavy as a methane molecule so the relative global warming potential of methane when considering biological emissions is only 7.6 times as much as carbon dioxide. Yet only once have I ever seen anyone from the global warming believers group explain this. Yet a check of the figures used to calculate the emissions for a farm shows that it is being done this way. They know the truth of it but they continue to tell all and sundry that methane is 21 times worse.
This does serious damage to the credibility of their whole argument. Why don’t they use facts rather than wild exaggerations?
You mention ‘if we keep adding methane to the atmosphere at rate we’ll see serious effects soon’. I disagree. The amount of methane in the atmosphere is only rising slowly, and the rate of rise is slowing. This is because of the equilibrium effect. If more methane is added to the atmosphere then the processes that break it down speed up. An analogy is adding wood to a fire. If you put more wood on it burns the wood more quickly. It doesn’t keep burning at the same rate.
Robert
Coming back as promised about the wetlands producing more methane:
The IPCC fourth report has a table that list the work of half a dozen researchers. The range for wetlands is 100 to 231. The average is 174
The range for ruminants is 76 to 92. The average is 84. Therefore wetlands are over twice as important for methane emissions.
You conclude by saying you can’t see why I am not a little alarmed. That is easy. I once believed that our greenhouse gases were going to be a problem but as the science has developed I have watched with an open mind and observed that it is far from settled. I noticed that the IPCC and those associated with it tended to make exaggerated claims. For example James Hansen predicted the sea would rise 10 feet in 40 years. That was nearly 30 years ago. Has it happened? No.
They also make claims that are not logical. They say we can’t have more carbon dioxide in the atmosphere. Yet plants would benefit from it and through them all other life forms as there would be more food.
Humanity itself would benefit from a warmer climate. In spite of the fact that the world’s population is concentrated in the tropics more people die of cold than heat. Similarly, plants would grow better giving more food.
In recent years it has become apparent that the IPCC temperature models are wildly exaggerated. It is now conceded by even the likes of the University of East Anglia and the British Met Office that there has been no significant warming for fifteen years. The current temperature is below the most conservative of the IPCC projections and has been for four of the last five years. Honest scientists ditch their models when facts come in that contradict them. Why are the IPCC scientists hanging on to theirs?
With solar physicists now suggesting the world could cool for the next twenty years I have real concerns. That will bring problems for humanity with crop failures and problems from the cold with people simply freezing as they did in the Little Ice Age. With our world governments so pre-occupied with the myth of global warming the effects will be worse as no preparation is being done. You should be worried too. It will be even colder at your end of the country. Forget the urea on the Southland farms.
Sorry, Neil, I'd not noticed your new, very comprehensive comments.
"But there is an organisation that calls itself 350.org that wants to reduce carbon dioxide levels back to 350 parts per million. It has a branch here in New Zealand."
You're not suggesting that these '350' people are wrong in calling for maintaining a level of 350 parts per million, are you? You seem to be equating any figure lower than we have now as being a threat to plant health. Surely you jest? We were quite comfortably getting by when we were sitting on the 350 mark, as I recall.
Regarding methane, I don't know about the 'equilibrium effect'(or rather, I don't know if one operates in the case of methane), so can't argue that, although my feeling is that if the de-frosting tundra is releasing large and constant amounts of methane into the atmosphere, there'll need to be some pretty fast 'equilibrium' going on to prevent harm occuring.
I simply don't believe that we are due for a freezing time ahead, based on all I have read and heard. You've presented plenty of commentary on that, but it doesn't ring true with me, as warming doesn't with you. I guess were not going to find common ground there.
Robert
I do not jest about lowering carbon dioxide to 350. This will lower plant growth rates, lowering crop yields. This means more land will be needed to feed the world, and thus creating pressure to clear more forests.
This will be excerbated by the current stupidity of growing biofuel crops to reduce emissions of fossil fuels. We have tractors ploughing paddocks to produce biofuel to run tractors to plough fields to produce biofuel to run tractors.... All this puts even more pressure on the forest and jungles.
Yes, if large amounts of methane are released from the tundra there will be a chnage in atmospheric levels. But the half life of methane is somewhere about eight years. That is the lenght of time it will take for the new equilibrium to come into effect. But is this tundra going to continue to thaw? After all the ice was thick enough to be able to hold the curling in Otago this year for the first time for many years.
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