Global Warming Debate: Refuting Common Arguments

[Mk]

There is no question that humans are destroying natural habitats at an alrming rate through agriculture, ranching, construction, destroying wetlands, destroying forests, killing off species that other species need to live on. But this is direct physical harm by man.

Wow Evo, you sound like a direct convert from the way you praised one of my posts in General Discussion a few years ago. What happened?

Assuming for the sake of argument that this is true, so what? Does the fact that a researcher is financed by Exxon-Mobil inherently mean they are lying? This is a logical fallacy called poisoning the well.

Actually a more accurate characterization would be a red herring fallacy known as an appeal to motive...

The warming that began at the beginning of the Holocene peaked about 7000 - 8000 years ago and the Earth has been cooling until the recent Anthropocene epoch.

Now that's poisoning the well.

Species do die all the time, but currently they are dying at some orders of magnitude faster than the long term average.

Bored Wombat, I'd like to know where it is you get your long-term data from. I can't quite imagine biologists empirically collecting meaningful biodiversity data thousands of years back. I am also unaware of the reliability of proxy data in the case of counting species over time.

 

[Evo]

Wow Evo, you sound like a direct convert from the way you praised one of my posts in General Discussion a few years ago. What happened?

That was an awesome post if I'm not mistaken, it was the one about humans, when they try to fix things, screw things up even worse.

Am I right? I don't think I've changed from that opinion. Do you have the link to that post? If it's the one I'm thinking of, it should be bronzed.

 

[Nebula815]

That was an awesome post if I'm not mistaken, it was the one about humans, when they try to fix things, screw things up even worse.

I have read about that with regards to nature, just shows how little we humans understand about the mechanics of the wilderness.

 

[Bored Wombat]

I'm faulting the '30% biodiversity drop' and 'observation' parts of your statement in #105, for which you attempt to use the LPI to show that these are widely accepted conclusions, but which if you read the reference actually contradict your statement there about biodiversity:


I contend a fair summary of these papers can go little further than to say something like "The Living Planet Index, a weighted index of vertebrate population data, has shown a ~30% decline from 1970 to 2000" without distorting the paper.

Okay. I accept the about 30% drop, and that it could be much more or much less.

The order of magnitude is the worrying thing.

And climate change is a significant player in this - particularly well documented is the invasion of sub Antarctic ecosystems by temperate species.

But certainly invasion of mountain amphibians by fungi is also noted. There are bat populations that have also been devastated by fungi too.

 

[Bored Wombat]

There is no question that humans are destroying natural habitats at an alrming rate through agriculture, ranching, construction, destroying wetlands, destroying forests, killing off species that other species need to live on. But this is direct physical harm by man.

There is also no question that climate change, overexploitation and pollution are killing of species.

This is also direct physical harm by man.

 

[Bored Wombat]

Right, and especially given the study referenced in this thread indicating that climate influences on species loss are overblown,...

Which study is that?
I've been reading this thread, and I didn't notice that study.

Because I'm aware of a lot of biodiversity loss in this part of the world that is due to climate change more than other factors.

So I'd like to learn that this is overblown, and that these ecosystems have not been destroyed.

 

[Bored Wombat]

Bored Wombat, I'd like to know where it is you get your long-term data from. I can't quite imagine biologists empirically collecting meaningful biodiversity data thousands of years back. I am also unaware of the reliability of proxy data in the case of counting species over time.

There are lots of estimates of biodiversity based on the fossil record. Speciation is hard to judge from the record, and so estimates vary about an order of magnitude.

What do you find hard to believe, and why?

 

[mheslep]

Which study is that?
I've been reading this thread, and I didn't notice that study.

Because I'm aware of a lot of biodiversity loss in this part of the world that is due to climate change more than other factors.

So I'd like to learn that this is overblown,

Andre referenced the paper and you commented on it:
http://www.sciencemag.org/cgi/content/summary/326/5954/806.
Kathy J. Willis and Shonil A. Bhagwat, Biodiversity and Climate Change Science 6 November 2009: Vol. 326. no. 5954, pp. 806 - 807
There have also been news summaries and paper excerpts were posted in thread.

...and that these ecosystems have not been destroyed.

Strawman. Nobody said that ecosystems have not taken a hit, in fact just the contrary has been stated by several posters concerning habitat loss through farming, development, etc. My comment, based on the paper, was climate influences on species loss are overblown. To head off any more strawmen, this does not mean that climate has no impact, or that we can't point to some isolated examples of climate influence on species loss. The paper attacks some of the existing, published, global estimates of species loss due to climate change, and shows why they're likely inaccurate.

 

[Bored Wombat]

Andre referenced the paper and you commented on it:
http://www.sciencemag.org/cgi/content/summary/326/5954/806.
Kathy J. Willis and Shonil A. Bhagwat, Biodiversity and Climate Change Science 6 November 2009: Vol. 326. no. 5954, pp. 806 - 807
There were news summaries and excerpts were posted.

Ah you mean that one paper looking at species ranges to predict drops in biodiversity produced an overestimate.

I thought you were saying that the observed drop in biodiversity that is attributed to climate change was overblown.

Strawman. Nobody said that ecosystems have not taken a hit, in fact just the contrary has been stated by several posters concerning habitat loss through farming, development, etc. My comment, based on the paper, was climate influences on species loss are overblown.

Then I would say that you've overstated the significance of the paper. The climate influences on species loss are not "overblown". A particular prediction, (that was already suspected to be high by applying it to biodiversity over the end of the last glaciation), was an overestimate, because there are niches smaller than the resolution of the other study in which a species will often survive.

But our understanding of climate influences on species loss is built up of ecological studies involving species and ecosystem loss, not that particular prediction of species loss in the coming decades.

Also, not a strawman. I was talking about ecosystems destroyed by climate change, not by land use change. Notably the subantarctic communities.

 

[Evo]

There are lots of estimates of biodiversity based on the fossil record. Speciation is hard to judge from the record, and so estimates vary about an order of magnitude.

What do you find hard to believe, and why?

What on Earth do fossil records have to do with the current gloabl warming debate? Unless you want to show that so called "global warming" has virtually no effect on species if you look at the fossil record and previous mass extinctions.

 

[Bored Wombat]

What on Earth do fossil records have to do with the current gloabl warming debate?

Well they provide an estimate of historical biodiversity, and therefore a guide as to what rate of drop in biodiversity can be maintained.

Did I misunderstand MK's comment?

It seemed to me (s)he was questioning the long term average extinction and speication rates by wondering about my "long term data".

What do you think they were referring to?

Unless you want to show that so called "global warming" has virtually no effect on species if you look at the fossil record and previous mass extinctions.

Warm periods are periods of high extinction and high speciation (of course current climate change is very fast, which greatly exacerbates the problem), in the fossil record, and previous mass extinctions all occur at times of climatic upheaval.

What do you mean by 'so called "global warming" has virtually no effect on species if you look at the fossil record'. Surely the opposite is the case?

 

[mheslep]

Ah you mean that one paper looking at species ranges to predict drops in biodiversity produced an overestimate.

No that is not what I mean, that is not what Willis and Bhagwa say.
Edit: If and until the paper becomes more generally available, a news summary:
http://www.timesonline.co.uk/tol/news/science/article6905082.ece"

“The evidence of climate change-driven extinctions have really been overplayed,” said Professor Kathy Willis, a long-term ecologist at the University of Oxford and lead author of the article

I thought you were saying that the observed drop in biodiversity that is attributed to climate change was overblown

No, I said ... what I said.

Then I would say that you're wrong. The climate influences on species loss are not "overblown". A particular prediction, (that was already suspected to be high by applying it to biodiversity over the end of the last glaciation), was an overestimate, because there are niches smaller than the resolution of the other study in which a species will often survive.
But our understanding of climate influences on species loss is built up of ecological studies involving species and ecosystem loss, not that particular prediction of species loss in the coming decades.

These kind of unsupported opinions belong over in the General Discussion, or Politics forums, not here.

Also, not a strawman. I was talking about ecosystems destroyed by climate change, not by land use change. Notably the subantarctic communities.

You replied to my post with

[...]So I'd like to learn that this is overblown, and that these ecosystems have not been destroyed.

attributing to me the claim that 'ecosystems have not been destroyed.' I did not say any such thing.

 

[Bored Wombat]

No that is not what I mean, that is not what Willis and Bhagwa say.
Edit: If and until the paper becomes more generally available, a news summary:
http://www.timesonline.co.uk/tol/news/science/article6905082.ece"

At the risk of repeating myself, this is about prediction studies, particularly "Extinction risk from climate change", Nature 2004, linked above.

And I agree that that paper makes overestimates.

It is not true that "climate influences on species loss are overblown," except in the context of prediction.

But that is not how climate influence on species loss is generally understood. Certainly not in ecology. It is understood by watching climate change cause species loss. And this is not overblown.

You replied to my post with
attributing to me the claim that 'ecosystems have not been destroyed.' I did not say any such thing.

Right. Because you were referring to predicted species loss.

If you were claiming that observed species loss was overblown, it would necessarily be a claim that ecosystems have not be destroyed (by climate change). I thought that that is what you were saying.

In conclusion, yes, predicted species loss is overestimated by the 2004 nature paper mentioned in your linked press article, and also linked above.

But the paper in your linked press article does not talk about the observed species loss due to climate change, or the unobserved, but yet to date species loss due to climate change.

 

[Evo]

BW, the number of species we know today have risen due to recent concentrated efforts to log species. The resulting figures showing what we think are losses of these species are also due to the recent concentrated efforts at tracking. Not that there has been any increase in extinctions, just an increase in tracking.

It's meaningless.

You want to see mass extictions, look at the fossil record.

Do you know that we have had extinctions on Earth that wiped out an estimated 95% of all life on the planet? This was the Permian-Triassic extinction. The Earth bounces back. Nothing man has done can even come close to the natural disasters that have hit the Earth in the past.

We're coming out of an ice age. Of course things are changing, they always change. Go back and learn about past climate events on Earth if you want to discuss current climate with any semblance of credibility. Someone here made the statement "Global Climate Change - perhaps the greatest challenge ever faced by civilization."

Well, if they mean the Ice Age, yes, I guess it was, but man adapted to the horrific changes and survived.

 

[Bored Wombat]

BW, the number of species we know today have risen due to recent concentrated efforts to log species.

Sure

The resulting figures showing what we think are losses of these species are also due to the recent concentrated efforts at tracking. Not that there has been any increase in extinctions, just an increase in tracking.

No.
The living planet index follows the same species. So the same species are tracked as they were 40 years ago.

And it can't be your genuine position that there has been no increase in extinctions surely?

It's meaningless.

No it's not. It's a measure of biodiversity by looking at populations of vertebrates.

You want to see mass extictions, look at the fossil record.

There are five especially big ones there. And we're probably standing in the middle of the sixth ... but it won't be on the fossil record for a million years or so.

Luckily the number of species around at any given time has another source of data if that time is the present.

You can look at the species.

In some ways this is better than fossil data, that has confounding factors as some species fossilise more than others.

Do you know that we have had extinctions on Earth that wiped out an estimated 95% of all life on the planet? This was the Permian-Triassic extinction. The Earth bounces back. Nothing man has done can even come close to the natural disasters that have hit the Earth in the past.

Well, nothing survived that that was bigger than about a cat. So if that's your standard of okay, then you're okay with the extinction of humans. Note that it would have been an unpleasant time to try to live through ... which is worth trying to avoid.

Also it doesn't bounce back very fast.

But this disaster is of a similar magnitude of the great extinctions of the past. One hopes not the Permian–Triassic, but it is difficult to imagine that this will look better than the Late Devonian extinction, which took about 70% of species. Given that we've lost about 30% in the 35 years to 2005, and there is no sign of that slowing yet.

So man can match some of the natural disasters that have hit Earth in the past. And by 2050 you'll probably be able to count the worse ones over the entire 4 billion year history of life on earth, with one hand in your pocket.

 

[Evo]

Sure

No.
The living planet index follows the same species. So the same species are tracked as they were 40 years ago.

And it can't be your genuine position that there has been no increase in extinctions surely?


No it's not. It's a measure of biodiversity by looking at populations of vertebrates.



There are five especially big ones there. And we're probably standing in the middle of the sixth ... but it won't be on the fossil record for a million years or so.

Luckily the number of species around at any given time has another source of data if that time is the present.

You can look at the species.

In some ways this is better than fossil data, that has confounding factors as some species fossilise more than others.


Well, nothing survived that that was bigger than about a cat. So if that's your standard of okay, then you're okay with the extinction of humans. Note that it would have been an unpleasant time to try to live through ... which is worth trying to avoid.

Also it doesn't bounce back very fast.

But this disaster is of a similar magnitude of the great extinctions of the past. One hopes not the Permian–Triassic, but it is difficult to imagine that this will look better than the Late Devonian extinction, which took about 70% of species. Given that we've lost about 30% in the 35 years to 2005, and there is no sign of that slowing yet.

So man can match some of the natural disasters that have hit Earth in the past. And by 2050 you'll probably be able to count the worse ones over the entire 4 billion year history of life on earth, with one hand in your pocket.

How can man match the cataclysmic events of comets and meteors striking the planet, multiple huge volcanoes erupting at once, gulf streams changed by the closure of a waterway due to volcanic activity? Not to mention the super fast Ice Age? Please post the proof that this is even feasable.

 

[mheslep]

Jumping in here:

BW, the number of species we know today have risen due to recent concentrated efforts to log species. The resulting figures showing what we think are losses of these species are also due to the recent concentrated efforts at tracking.

Agreed.

Not that there has been any increase in extinctions, just an increase in tracking.

I don't think that's accurate. There have been some fairly long term studies (BW posted some peer reviewed references) looking at fixed species collections and they have definitely shown species loss in those collections. These collection sizes are in the thousands compared to the global ecosystem of millions, but they scientific studies none the less. We just don't know how representative those studies are of the world at large, but they can't be dismissed either.

You want to see mass extictions, look at the fossil record.

Do you know that we have had extinctions on Earth that wiped out an estimated 95% of all life on the planet? This was the Permian-Triassic extinction. The Earth bounces back. Nothing man has done can even come close to the natural disasters that have hit the Earth in the past.

If we look at the entire history of Homo sapiens apparently our impact does indeed approach some of those lesser disasters.

You're referring here to the http://en.wikipedia.org/wiki/Extinction_event#Major_extinction_events"ons over geologic time, the last one the famous dinosaur killer 65mya. However, there are indeed several well known biologists calling the Homo Sapiens period a 'sixth' extinction event. They mean by this the period from now going back 40,000 years, still short by these time scales. The causes include the modern ones you listed earlier, but also, over the millennia, general predation by HS and the rapid introduction of invasive species to isolated ecosystems made possible only by HS travel. I make no comment here on whether of not this is simply nature's way, but the fact is we whacked a lot of the low hanging fruit (Mastodons) as we came down out of the trees. Many of those species were probably on the edge of existence independent of HS, but we as top predator pushed them over. Per some biologists, HS past action combined with modern habit destruction is indeed adding up to a reduction in species loss comparable to some of the lesser earlier extinctions.

I can't find a peer reviewed article making this point so take this for what its worth, and I won't post any non peer reviewed links here. However, a google search for 'sixth extinction' will bring up a lot of material written in popular form by working biologists.

 

[heldervelez]

Earth is dominated since recent times by 'hot blood' animals that have internal solutions to be hotter than environment.

This is in contrast with extinguished solutions (cold blood) that, who kowns, could have solutions to be colder than environment.

To me it strongly suggest the long trend Earth's temperature declining.
And big extinctions could be tied to this fact.

 

[Sorry!]

Earth is dominated since recent times by 'hot blood' animals that have internal solutions to be hotter than environment.

This is in contrast with extinguished solutions (cold blood) that, who kowns, could have solutions to be colder than environment.

To me it strongly suggest the long trend Earth's temperature declining.
And big extinctions could be tied to this fact.

What exactly are you trying to say in this post?

 

[Sorry!]

I can't find a peer reviewed article making this point so take this for what its worth, and I won't post any non peer reviewed links here. However, a google search for 'sixth extinction' will bring up a lot of material written in popular form by working biologists.

I've read this in a book I'll look through my collection to see if I can recall the title to reference for you; this is a very real situation though. It is different than the past extinction events occurring more due to pollution, changing landscape, us taking animals from one location and putting them in another, and of course 'over-hunting' (couldn't think of a better word haha).

Do you know that we have had extinctions on Earth that wiped out an estimated 95% of all life on the planet? This was the Permian-Triassic extinction. The Earth bounces back. Nothing man has done can even come close to the natural disasters that have hit the Earth in the past.

This extinction event wiped out approximately 54-58% of families around at the time. Probably something closer to 70-75% of species on Earth (some families are huge and some are small); not 95%.

Anyways aside from that you are comparing the greatest extinction event ever observed on our planet to what humans can cause. All of the other extinction events were much smaller (If my memory is correct only up to 24% of families going extinct average probably around 20%). I have no doubts in my mind that we are currently in a man-caused extinction event, I'll look for that book see the references in it. (the ones specifically relating to increase in temperature.)

 

[vanesch]

For me, the worst possible extinction is that of the skiing resorts close to me, and that by itself merits that the world changes attitude!

 

[DanP]

I know nothing about climate, but one thing bothers me, and I would like to know more:

How do we know that global warming is anomalous ? After all we had multiple glacial eras, and I am pretty sure that between said eras periods of global warming existed.

 

[sylas]

I know nothing about climate, but one thing bothers me, and I would like to know more:

How do we know that global warming is anomalous ? After all we had multiple glacial eras, and I am pretty sure that between said eras periods of global warming existed.

It depends what you mean by "anomalous".

Here's a quick summary of what seems to be pretty basic.

The rate of temperature increase at present is unusual, but most likely not unprecedented. (Although of course it is very hard to get accurate measurements of short term rates of change in the distant past.)

The amount of temperature change so far is a long way off much larger changes seen in the past.

The global temperatures being reached now are quite likely to be a new high for the Holocene, or at least for the last couple of thousand years, but still probably not quite as high as the most recent interglacial some 120,000 years ago or so.

The main driver for change in the present is something new; a change in atmospheric composition driven by human industrial emissions. That's a new factor.

If temperatures continue to increase (which by now seems to be no longer in any credible doubt) then the current episode of warming is likely to be a clear anomaly for an extended high rate of change, with few credible equivalents in the past. The actual temperatures likely to be reached are still very uncertain, however. It is quite likely to see a new high mean global temperature that beats out anything for several million years; but still not up to temperatures likely to have been in place in the early part of the current Cenozoic Era, say, 50 million years ago.

Definite answers, however, are not really possible, given inaccuracies in measurements of climate in the past and uncertainties about how temperature will behave over the next century.

Cheers -- sylas

 

[Sorry!]

It depends what you mean by "anomalous".

Here's a quick summary of what seems to be pretty basic.

The rate of temperature increase at present is unusual, but most likely not unprecedented. (Although of course it is very hard to get accurate measurements of short term rates of change in the distant past.)

The amount of temperature change so far is a long way off much larger changes seen in the past.

The global temperatures being reached now are quite likely to be a new high for the Holocene, or at least for the last couple of thousand years, but still probably not quite as high as the most recent interglacial some 120,000 years ago or so.

The main driver for change in the present is something new; a change in atmospheric composition driven by human industrial emissions. That's a new factor.

If temperatures continue to increase (which by now seems to be no longer in any credible doubt) then the current episode of warming is likely to be a clear anomaly for an extended high rate of change, with few credible equivalents in the past. The actual temperatures likely to be reached are still very uncertain, however. It is quite likely to see a new high mean global temperature that beats out anything for several million years; but still not up to temperatures likely to have been in place in the early part of the current Cenozoic Era, say, 50 million years ago.

Definite answers, however, are not really possible, given inaccuracies in measurements of climate in the past and uncertainties about how temperature will behave over the next century.

Cheers -- sylas

Well, we have been in an interglacial period of the Ice Age for close to 12,000 years. In the last say 100 years we have noticed a dramatic increase of temperature.
What's unusual I believe is the rate of change not the change itself.

It's almost impossible to say that humans do not contribute to the greenhouse effect which is known to raise temperatures of the planet. (Yes, the greenhouse effect exists even without humans, so to argue that there's no such thing as a greenhouse effect isn't exactly the best method.)

 

[DanP]

Well, we have been in an interglacial period of the Ice Age for close to 12,000 years. In the last say 100 years we have noticed a dramatic increase of temperature.
What's unusual I believe is the rate of change not the change itself.

Meaning that you can compare current rate with any other local rate (lets say over 50 years)which occurred during the last 2 ice ages ?

 

[sylas]

Meaning that you can compare current rate with any other local rate (lets say over 50 years)which occurred during the last 2 ice ages ?

Yes, as long as you have some suitable data to use. However, the comparisons are limited in accuracy. Your best bet is a comparison with rises coming up out of the last glacial maximum and into the Holocene, since this is the most recent, and does include some rapid changes. Unfortunately, it is particularly hard to look at a genuinely global rate of temperature rise in the past.

Never-the-less, a possible comparison is the Younger Dryas, a short (1,200 years) return to glacial conditions on the way from the glacial maximum to the balmy conditions of the Holocene. The end of the Younger Dryas seems to have been particularly abrupt.

One problem is that it is not clear how abrupt the global change might have been; but the local change in Greenland, which can be estimated from ice core data. An estimate from 1989 suggests 7 degrees increase in fifty years in Southern Greenland. That is a lot more rapid that what we have at present. Reference: Dansgaard, W. et. al. (1989) The abrupt termination of the Younger Dryas climate event, in Nature 339, pp 532-534 (15 June 1989).

The impact was felt more widely, but may not have been that abrupt in other regions. Others may have better references for this event.

This is why I say the current rate of change is anomalous... but not unprecedented. There have been other times with an anomalous rate of change.

Cheers -- sylas

 

[Integral]

We are discovering tons of new species all of the time.



http://www.cnn.com/2009/TECH/science/08/11/eco.himalayas.newspecies/index.html#cnnSTCText



http://www.cnn.com/2009/TECH/science/09/26/mekong.species/index.html#cnnSTCText



http://www.cnn.com/2008/TECH/science/12/16/rat.mekong/index.html#cnnSTCText

The list goes on and on.

This is a huge red herring.

What does the discovery of new species have to do with anything. One could argue that a changing climate would create new niches into which new species would evolve to fill. Meanwhile the species adapted to the old climate would expire. So it would not be to far fetched to expect a blossoming of new species in time of a climate change.

Yep, no peer reviewed links, but then, Evo, I do not see any peer reviewed links of yours showing the link between new species and climate change.

I do not think there is anyone who thinks that climate change will threaten life on earth, or for that matter even the human race. Short of a major catastrophe, life on Earth and man will continue no matter what the climate does in the next millennia. What is at risk is life as we now know it. The question is not whether man will survive, but whether our civilization will.

 

[Integral]

New estimates have been coming out that show there's more oil than once thought. We're developing the technologies to actually get this oil. OPEC can just say there's xxxx oil left when there's actually yyyy oil left. There's an interview with an OPEC representative on YouTube that I'm trying to find.

...

So the message I get from you is, don't worry there is an infinite amount of fossil fuels and we will never run out.

What does it matter what the latest discovery is, it does not change the fact that there is a finite amount of fossil fuels available. It does not change the fact that every new discovery is deeper and harder to get to with lower overall yields. If we want to ensure that our grandchildren and their grandchildren have a technology driven lifestyle we need to start developing renewable sources of energy. We simply cannot assume that we will always find more fossil fuels.

 

[DrClapeyron]

If we want to ensure that our grandchildren and their grandchildren have a technology driven lifestyle we need to start developing renewable sources of energy. We simply cannot assume that we will always find more fossil fuels.

Are grandchildren that hopeless that they cannot figure how to heat their homes or fuel their cars? I remember being told by my father that necessity is the mother of invention, not inconvenience.

The day will come when people blast 20 billion solar pannels up into space and use microwaves to beam back energy, but I think we are far from that time.

 

[Integral]

Are grandchildren that hopeless that they cannot figure how to heat their homes or fuel their cars? I remember being told by my father that necessity is the mother of invention, not inconvenience.

The day will come when people blast 20 billion solar pannels up into space and use microwaves to beam back energy, but I think we are far from that time.

Sure they can, the question is whether they heat their home with electricity or cow dung.

This is not an impossible outcome if by some weird accident the AGW camp is correct.