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theycallmeebryan 10-29-2009 09:27 AM

< 350ppm CO2 : Where we need to aim
 
350.org

On Saturday, there was a worldwide rally to promote James Hansen's theory of 350ppm atmospheric CO2 as a "safe" level for sustainable life on Earth. About 5200 different organized rallies occurred all over the world.

I just wanted to give a heads up to everyone here on Ecomodder. Even if it makes you think for a second, or if it adds to your ecomodding edge, i think its information everyone should know.

Here is James Hansen's original paper published on the topic suggestion 350ppm as a safe point. Earth used to be about 260-270ppm before civilized human life thrived. That number is considered the natural atmospheric CO2 levels for earth. We are currently at levels of 387ppm CO2. If we reach levels any higher (and we WILL given current trends), we will face complete loss of ice caps on the planet and we will see species pass.

http://arxiv.org/ftp/arxiv/papers/0804/0804.1126.pdf

THIS IS WHY WE ECOMOD! :turtle:

Piwoslaw 10-29-2009 10:12 AM

I found out about just before Saturday: The Big Ask. (Oh, how I love crosslinking:) )
Here in Warsaw they were supposed to be collecting signitures between 10am-1pm. I called up a friend and showed up at 12:30 and there wasn't any one there! Just the usual groups of tourists. No banners, no balloons, no tables where we could sign the petition. My wife says that they probably quickly got the number of signitures they needed and didn't want to sit in the cold and rain. Not nice of the organisation that was responible for it :(

chuckm 10-29-2009 02:52 PM

Quote:

Here is James Hansen's original paper published on the topic suggestion 350ppm as a safe point. Earth used to be about 260-270ppm before civilized human life thrived. That number is considered the natural atmospheric CO2 levels for earth. We are currently at levels of 387ppm CO2. If we reach levels any higher (and we WILL given current trends), we will face complete loss of ice caps on the planet and we will see species pass.
Please don't blast me for saying this, but I have a bone to pick with Hansen's science. While I do not doubt that global warming is real and it is, to some extent, anthropogenic, I have doubts about how bad moderate warming is. Why?
First, 90% of the past 400,000 years have been characterized by ice age. Ice ages are, to put it mildly, going to be detrimental to food production for humans and other species. Let's say that we bring down CO2 to Hansen's 260-270ppm level. Well, during the "Little Ice Age" (approx. 1550-1850AD), CO2 levels hovered around the 280ppm level. The twelve thousand year Holocene era, which we live in, has also been warmer - between 2-5ºC warmer! That warm time period, about 7000 - 5000BC, was associated with the rapid transition from nomadism to the development of agriculture and sustainable human culture. Humanity also thrived during the Medieval Warm Period, ~800 - 1300AD, where temperatures were ~1ºC warmer than today.
I have two points here: a) It is not the hottest it's ever been and b) Warmer temperatures are not historically linked to humanity fairing poorer.

jamesqf 10-29-2009 10:58 PM

Quote:

Originally Posted by chuckm (Post 136676)
Ice ages are, to put it mildly, going to be detrimental to food production for humans and other species.

This is not the case. Biological productivity is highest in the Arctic and Antarctic oceans, while human food production is greatest in the temperate regions. Tropical jungles give a misleading impression, because much of the tropical world (including those pretty clear blue ocean waters) is in fact desert.

You might consider the megafauna that ranged North America during the last Ice Age: everything from wooly mammoths to the sabertooths & dire wolves that preyed on them. Fast-forward to immediate pre-Columbian times, and only a few moderately large herbivores remained - buffalo, moose, & elk.

Quote:

That warm time period, about 7000 - 5000BC, was associated with the rapid transition from nomadism to the development of agriculture and sustainable human culture.
I think you're looking at this backwards, and that it's more likely that agriculturally-supported urbanism arose because the warmer climate made it harder to support the nomadic lifestyle. Whichever's the case, though, you might want to consider the quality of life of the nomad versus the typical urban dweller (not the elites, IOW). Indeed, you might think about their relative quality of life nowadays, too. Urbanism may have been a necessary phase in human history, but it sure wasn't and isn't a quality life.

chuckm 10-30-2009 07:38 AM

Quote:

This is not the case. Biological productivity is highest in the Arctic and Antarctic oceans, while human food production is greatest in the temperate regions. Tropical jungles give a misleading impression, because much of the tropical world (including those pretty clear blue ocean waters) is in fact desert.
I'm not sure how you are defining "biological productivity." Biological density is higher, by an order of magnitude, in temperate climates than in Arctic and Antarctic.
Quote:

I think you're looking at this backwards, and that it's more likely that agriculturally-supported urbanism arose because the warmer climate made it harder to support the nomadic lifestyle. Whichever's the case, though, you might want to consider the quality of life of the nomad versus the typical urban dweller (not the elites, IOW). Indeed, you might think about their relative quality of life nowadays, too. Urbanism may have been a necessary phase in human history, but it sure wasn't and isn't a quality life.
Umm... you seem to be saying that nomadism is a preferred life style? Weird.

captainslug 10-30-2009 08:18 AM

Setting arbitrary Co2 benchmarks is pure bull****. Especially if such figures don't really reflect a correlation to global quality of life and food production.
The climate always has and always will change. We're not evenly remotely close to global temperatures being "too high".

Besides the above: Co2 levels are not the cause of temperature averages, they are an outcome.

NeilBlanchard 10-30-2009 08:58 AM

Arbitrary?

How do you think the atmosphere keeps in the heat from the sun?

Changes have always been happening sure -- but how FAST were the changes in the past? Going up or down a degree C in 100,000 years is easy, but having that change in ~100 years is another thing altogether.

We will probably lose all the ice in the Arctic in the summer within the next 10 years. This will accelerate the warming, because of the low albedo of open water vs the higher albedo of snow and ice. Additional warming will then melt the permafrost more quickly -- which will release lots of methane -- which is ~20X stronger greenhouse gas than is carbon dioxide. And so the very quick warming will become even quicker.

jamesqf 10-30-2009 12:37 PM

Quote:

Originally Posted by chuckm (Post 136810)
I'm not sure how you are defining "biological productivity." Biological density is higher, by an order of magnitude, in temperate climates than in Arctic and Antarctic.

Biological productivity = amount of living matter produced per unit area. You need to look at the oceans as well as the land.

Quote:

Umm... you seem to be saying that nomadism is a preferred life style? Weird.
Why would you think so? Don't want to get into a long discussion, but just look at the differences. On the one hand you've open space, natural surroundings, varied food available for the hunting & gathering, which takes a few hours a day, the chance to do different things every day. On the other hand, your typical urban dweller of those days crammed a family into a single room, and survived on a sparse diet of mostly grains. Even into Shakespeare's time and later, streets were often open sewers, the air was full of smoke & stink, disease abounded. The great majority of people worked long hours for little return beyond survival. Humm... seems like some things haven't changed all that much :-)

chuckm 10-30-2009 12:44 PM

Quote:

Changes have always been happening sure -- but how FAST were the changes in the past? Going up or down a degree C in 100,000 years is easy, but having that change in ~100 years is another thing altogether.
Not so. Google "8.2k event". During the Holocene Climatic Optimum (the warm period mentioned in my post above), there was a climatic, uh, bump in the road. As ice sheets retreated, a large North American fresh water lake suddenly drained into the North Atlantic, generating a large scale shift in ocean currents. The fallout was this: in a five year time span, the earth cooled by an astounding 6ºC and remained this cold for about 60 years. Also, to counter jamesqf's belief that a nomadic culture is happier, this event seems to coincide with the collapse of the first human settlements (archeological sites in Iraq, Israel, and Jordan) and their remission into hunter-gatherer culture. When the climate did recover from this cold snap, it then warmed up 6ºC in just 100 years. By comparison, some of the worst-case climate models show us warming by 5ºC in the next 100 years (as a note, these models are already showing divergence from actual conditions, ie, we're not as warm as we should be). The return to warm conditions coincides with the rise of the ancient cultures of the fertile crescent we know so much about. And again, global temperatures were higher than the present day.

Quote:

Arbitrary?
I won't go so far as to say "arbitrary" - but I don't believe that 350ppm is scientifically justified. Why? Simply this: Water vapor and clouds are the dominant players in the greenhouse game. They account for 66-85% of the greenhouse effect. CO2 contributes about 9-25%, with methane and other GHGs filling out the rest. (FYI - The variability in the percentage is largely dependent upon relative humidity and cloud cover.) The CO2 reinforcement of the positive feedback loop of the water vapor cycle is mitigated by two forces: 1) dust generation in dry conditions leads to cloud formation and 2) the power of evaporative cooling. On the first, clouds reflect solar radiation even while they absorb re-radiated heat from earth. On the second, yes, higher atmospheric temperatures mean a larger capacity for water vapor, but getting more vapor in the atmosphere takes tremendous amounts of solar energy, which puts negative feedback into the loop.

Please do not misunderstand or misrepresent my opinions here. I do believe that we must work on being better stewards of the Earth and our resources. I do believe that we should develop cleaner and more efficient energy sources. I also believe that cheap, clean and efficient energy sources has the potential to raise billions of people out of poverty - meaning that developing this clean energy is imperative from a humanitarian perspective. While I do believe in anthropogenic climate changing forces, I do not believe that anthropogenic warming is, as of yet, the dominant force in our global climate. I believe this to be the case because of the past.
http://www.geocraft.com/WVFossils/Pa...0-400k_yrs.gif

Climate changes in the past have been sudden and dramatic. Did humans, 130,000 years ago, cause the temperature peak shown in this graph? Unless our great(5x 10^3)grand-daddy Ugg the Clumsy accidently started the largest forest fire ever, obviously not. No, other forces, Milankovitch cycles for example, are a bigger player than we could ever pretend to be.

chuckm 10-30-2009 01:00 PM

Quote:

Why would you think so? Don't want to get into a long discussion, but just look at the differences. On the one hand you've open space, natural surroundings, varied food available for the hunting & gathering, which takes a few hours a day, the chance to do different things every day. On the other hand, your typical urban dweller of those days crammed a family into a single room, and survived on a sparse diet of mostly grains. Even into Shakespeare's time and later, streets were often open sewers, the air was full of smoke & stink, disease abounded. The great majority of people worked long hours for little return beyond survival. Humm... seems like some things haven't changed all that much
In urban settings, we do have different worries, to be sure. But why would cultural evolution favor urbanism over nomadism? If nomadism provides better life and health, why didn't that lifestyle come to dominate modern human populations? Simply this, nomads were too busy with their "few hours a day" hunting and gathering and surviving in general to develop things like writing and science. (Just curious, have you ever tried to live off the land, lacking any tool you could not make from wood or stone? I haven't, but rumor has it that it is tough. Starvation is one of many occupational hazards. I wouldn't spend too much time romanticizing this life.)

From an earlier post:
Quote:

You might consider the megafauna that ranged North America during the last Ice Age: everything from wooly mammoths to the sabertooths & dire wolves that preyed on them. Fast-forward to immediate pre-Columbian times, and only a few moderately large herbivores remained - buffalo, moose, & elk.
Much of the rise and fall of the warm-blooded megafauna has to do with thermal regulation. In a cold climate, heat retention is a big deal and large animals do better than small animals there. For small animals, the caloric requirement per pound of body mass needed only to maintain body temperature becomes a problem. In very warm climates, heat dissipation becomes the dominant issue, favoring smaller animals. A large animal (apart from special adaptations - the ears of the African elephant being one) exerting itself can quickly die from overheat. A wooly mammoth in a warm environment would be forced to either move slowly (making it easy, high calorie prey!) or risk dying of overheating (which early humans probably prodded the animals into doing - again easy prey).

chuckm 10-30-2009 01:29 PM

Quote:

Biological productivity = amount of living matter produced per unit area. You need to look at the oceans as well as the land.
I'm okay with that. But after googling for "high latitude biological productivity", I haven't seen anything thus far that supports the idea that "Biological productivity is highest in the Arctic and Antarctic oceans..." In fact, as pertinent to this discussion, I did find this abstract: SHIFTING OCEAN PRODUCTIVITY PATTERNS DURING THE INTENSIFICATION OF NORTHERN HEMISPHERE GLACIATION. In the abstract, it states that "We find that biological productivity in all high latitude regions declines precipitously in association with the intensification of (Northern Hemisphere Glaciation)." So that I might better understand, please point me to your source.

jamesqf 10-30-2009 06:41 PM

Quote:

Originally Posted by chuckm (Post 136844)
If nomadism provides better life and health, why didn't that lifestyle come to dominate modern human populations?

Armies.

Big Dave 10-30-2009 07:35 PM

I Have no use for this Hansen dude. He cooks his data.

I thought we were supposed to stick to the cars.

chuckm 10-30-2009 08:41 PM

Big Dave - You're right. On both counts. Sorry for starting the debate.

NeilBlanchard 10-30-2009 11:29 PM

Hi,

How is it that a couple of guys on an Internet forum are better scientists than a head of NASA?

James Hansen is one of the most visible people on the global climate change, but he is certainly not the only one.

Get ready for some Fact Bombs:

ApteraForum.com - Aptera Car Forum - View Single Post - End of Global Warming

ApteraForum.com - Aptera Car Forum - View Single Post - End of Global Warming

ApteraForum.com - Aptera Car Forum - View Single Post - End of Global Warming

ApteraForum.com - Aptera Car Forum - View Single Post - End of Global Warming

chuckm 10-31-2009 04:08 PM

NeilBlanchard and jamesqf,
Because, as Big Dave pointed out, ecomodder is focused on cars, I've replied to you with a PM.

NeilBlanchard 10-31-2009 04:36 PM

Hi,

This thread probably should be moved to The Lounge? But I think it is perfectly legit to discuss this topic in "public".

jamesqf 10-31-2009 06:42 PM

Quote:

Originally Posted by chuckm (Post 136844)
But why would cultural evolution favor urbanism over nomadism? If nomadism provides better life and health, why didn't that lifestyle come to dominate modern human populations?

Remember that we're talking about quality of life - or at least I am - and especially QOL for the average individual. The advantage of cities is that they allowed more specialization, but that came at a cost. For every Socrates or Plato, you had maybe ten thousand helots (and a thousand soldiers to keep them in line). So you had a few, up at the top of the pyramid, developing the arts of civilization and enjoying a pretty decent lifestyle. Average their QOL out with those down at the bottom, and it's not such a pretty picture at all.

When we get to dominance, it's those armies again. The top of the urban pyramid has those soldiers keeping the helots in check, so they might as well use them - and all the other arts - to go out and dominate some nomads. Besides, the helots tend to wear out rather quickly, so it helps to acquire a fresh supply every now & then.

chuckm 10-31-2009 10:27 PM

Quote:

Remember that we're talking about quality of life - or at least I am - and especially QOL for the average individual. The advantage of cities is that they allowed more specialization, but that came at a cost. For every Socrates or Plato, you had maybe ten thousand helots (and a thousand soldiers to keep them in line). So you had a few, up at the top of the pyramid, developing the arts of civilization and enjoying a pretty decent lifestyle. Average their QOL out with those down at the bottom, and it's not such a pretty picture at all.
Okay, I still don't think living in tents and praying for a successful hunt at least once a week are better than an urban and agricultural life.

rmay635703 10-31-2009 11:40 PM

Quote:

Originally Posted by chuckm (Post 137073)
Okay, I still don't think living in tents and praying for a successful hunt at least once a week are better than an urban and agricultural life.

Actually traditional prehistoric hunter gatherers typically
1. Worked an average of 2 hours per day
2. Took an afternoon nap when climate allowed (we are designed to nap)
3. Lived as long as we do, oddly hunter folks always outlived the agricultural folks, they lived long enough into old age to get advanced arthritis. (assuming natural disaster, starvation or some form of blunt force death didn't occur)
4. Hunters rarely had heart disease, diabetes. cancer and most of the common modern ailments, whereas most agricultural societies had huge increases in heart disease, especially grain based societies. Look at Egypt, they had huge problems with obesity, heart disease and only lived to about 21 and they ate almost solely grain.

The above ONLY apply to those who were strictly hunter gatherer, not the hybreds like native americans who tended to also farm on the side. Usually they were restricted to favorable climate as well thus eliminating many of the weather related hardships.

You can find the facts I list above from more than one source and aren't speculation.

So although we have cool stuff we are paying for it in more than one way.

chuckm 11-01-2009 06:36 PM

I seriously question assertions 1 and 3. I don't have any reason to doubt 2. I'd put a huge asterisk on 4.
1) Typically about 80% of the paleolithic diet came from gathering. Gathering sufficient food to provide about 900 digestible calories per day, with enough variation to provide all the required nutrients probably took more than 2 hours, especially during winter. Hunting with primitive weapons is a dubious thing (anybody here ever tried to hunt with a spear? a bow and arrow made from sticks, a stone, and plant-fiber twine?) and probably involved much more than 2 hours a day and had a low success rate.
3) The sources I've found put paleolithic life expectancies between 33 and 54 (if you made it past 15 years old, you had a good chance of making it to 39-54). In the neolithic, life expectancy was about 20. Could you point me to your source?

Quote:

The above ONLY apply to those who were strictly hunter gatherer, not the hybreds like native americans who tended to also farm on the side.
The problem with that is that paleolithic populations were processing cereal grains for food some 23000 years ago, with evidence suggesting as early as 200,000 years ago (Piperno, D; Weiss, E., Hols, I., Nadel, D (2004), 200,000 years from People, Plants and Genes: The Story of Crops and Humanity. Oxford: Oxford University Press.). Everybody would be, as you termed it, a hybrid.

FYI, both the American Dietic Association and the National Health Service of England have designated the "Paleolithic diet" (aka caveman diet) as a fad diet.

rmay635703 11-01-2009 06:52 PM

Actually 3 is still true assuming that they don't die from some sort of brute force or starvation. The longest lived peoples on the planet also live the most simplistically. And that tends to be regardless of whether its meat or vegetable. There are many examples of 60/70+ year old individuals from tropical basin hunter gathers.

1. is also true when you limit it to our origins in the tropical basin, people generally didn't survive into the cold blue yonder as hunter gathers.

4. Is almost always true when comparing a traditional diet to a grain based diet. The diet of wheat that has been pushed down our throats was historically proven to be the worst as exemplified by the Egyptian culture.

The low sucess rate now can be attributed to us having a vastly different world than of many years past, with very few people and lots of animals, especially in the the tropical basin, hunting would not be difficult and would not occupy all of your day since a little cooperation can net one larger animal feeding the group. Our ancestors DID NOT start in the cold barren wasteland but in regions where they could live near naked.

The lifespan averages again typically involve a lot of speculation and a lot of deaths due to being killed by something or falling or whatever. Historically men were killed by something other than old age.

Quote:

Originally Posted by chuckm (Post 137184)
I seriously question assertions 1 and 3. I don't have any reason to doubt 2. I'd put a huge asterisk on 4.
1) Typically about 80% of the paleolithic diet came from gathering. Gathering sufficient food to provide about 900 digestible calories per day, with enough variation to provide all the required nutrients probably took more than 2 hours, especially during winter. Hunting with primitive weapons is a dubious thing (anybody here ever tried to hunt with a spear? a bow and arrow made from sticks, a stone, and plant-fiber twine?) and probably involved much more than 2 hours a day and had a low success rate.
3) The sources I've found put paleolithic life expectancies between 33 and 54 (if you made it past 15 years old, you had a good chance of making it to 39-54). In the neolithic, life expectancy was about 20. Could you point me to your source?


The problem with that is that paleolithic populations were processing cereal grains for food some 23000 years ago, with evidence suggesting as early as 200,000 years ago (Piperno, D; Weiss, E., Hols, I., Nadel, D (2004), 200,000 years from People, Plants and Genes: The Story of Crops and Humanity. Oxford: Oxford University Press.). Everybody would be, as you termed it, a hybrid.

FYI, both the American Dietic Association and the National Health Service of England have designated the "Paleolithic diet" (aka caveman diet) as a fad diet.


chuckm 11-01-2009 06:58 PM

The following is a PM I sent to NeilBlanchard in response to his post.

Regarding the first Apteraforum post: I fully acknowledge that temperatures from ca. 1880 have increased. However, it should be noted that earth was just coming out of the "Little Ice Age." One should hope that temperatures since then have increased! Lookup the following: the Maunder minimum, the Irish famine of 1740-41, the year without a summer (1816 BTW, when the already below average temps were further impacted by a massive volcanic eruption). WRT the Little Ice Age, global warming was a GOOD thing.

It's not that I'm better educated than Hansen... I'm not. I do not pretend to be a climatologist. I do not think I've put on airs like I am one... but I am not utterly unable to read a scientific paper or read a graph of the data. In that regard, can you find fault with the facts I've presented? I know you disagree with my conclusions, but are the facts I've presented erroneous?
For example, is it a fact that, in the past 400,000 years, it has been warmer on several occasions?
http://upload.wikimedia.org/wikipedi...emperature.png
Is it a fact that temperatures during the Holocene Climatic Optimum was warmer than present?
http://upload.wikimedia.org/wikipedi...Variations.png

Is it a fact that the Medieval Warm Period had temperatures comparable to the present 10 year averages?
http://upload.wikimedia.org/wikipedi...Comparison.png

Was I incorrect regarding the 8.2k event, mentioned in one of my posts? Was I in error regarding the relative impacts of the various greenhouse gases?

I think Hansen is disingenuous in representing 260-270ppm as "normal," considering that CO2 concentrations have, in earth's history have been much higher. What's normal? The Devonian period had mean CO2 levels of 2200ppm. The Carboniferous period had mean CO2 levels of 800ppm. The Permian: 900ppm. The Triassic: 1750ppm. The Jurassic: 1950ppm. The Cretaceous: 1700ppm. The Paleogene seems to have ranged from 1000-1500ppm. Only in the pre-modern human Neogene and Quaternary periods do we see CO2 drop into the 280ppm range. Interestingly, some of the Neogene and much of the Quaternary is also dominated by glaciation. Thus, what Hansen is defining as "normal" is glaciation. The current temperatures and global ice volumes, however, are not much different than other interglacial periods (see ~125,000, ~300,000, and ~400,000 years ago and, to a lesser extent 200,000 years ago).

chuckm 11-01-2009 07:17 PM

Quote:

Actually 3 is still true assuming that they don't die from some sort of brute force or starvation. The longest lived peoples on the planet also live the most simplistically. And that tends to be regardless of whether its meat or vegetable. There are many examples of 60/70+ year old individuals from tropical basin hunter gathers.

1. is also true when you limit it to our origins in the tropical basin, people generally didn't survive into the cold blue yonder as hunter gathers.

4. Is almost always true when comparing a traditional diet to a grain based diet. The diet of wheat that has been pushed down our throats was historically proven to be the worst as exemplified by the Egyptian culture.
Could you help me with some sources? Thanks!

Quote:

The low sucess rate now can be attributed to us having a vastly different world than of many years past, with very few people and lots of animals, especially in the the tropical basin, hunting would not be difficult and would not occupy all of your day since a little cooperation can net one larger animal feeding the group.
Actually, humans typically have done more to decimate predator populations, meaning an over-abundance of prey animals. Check out the populations of white-tailed deer in North America... or on your bumper. Besides, wouldn't evolution tend to kill off easy prey before humans even came into the picture? I don't think gazelles became tremendous runners in the last 20,000 years.
Quote:

Historically men were killed by something other than old age.
Agreed. Disease often did the trick too. But again, if you could point me to some sources that support your assertion, it would be very helpful. Thanks again.

jamesqf 11-02-2009 12:54 AM

Quote:

Originally Posted by chuckm (Post 137184)
Hunting with primitive weapons is a dubious thing (anybody here ever tried to hunt with a spear? a bow and arrow made from sticks, a stone, and plant-fiber twine?) and probably involved much more than 2 hours a day and had a low success rate.

Opinions differ on that, for instance The Atlatl and Dart: An Ancient Hunting Weapon

You need to keep in mind that things like hunting become much easier when you practice the skills continuously, rather than for a couple of weeks in hunting season.

chuckm 11-02-2009 09:13 AM

The effective range of the atlatl was about 20-30 yards (accuracy and penetration) for thin-skinned mammals. Perhaps 40 yards with a very well made one (dowel-like straight pieces of wood simply don't fall off trees, so these were probably exceptionally rare).
Again, my point is simply that I seriously doubt that 2 hours of hunting could consistently provide meat. If it were that easy, why would neolithic man tie up valuable time and resources by working to domesticate cattle and protect them from predation?
FYI, pastoralism (nomadism + herding) is a typical intermediate state between agrarianism and nomadism.

jamesqf 11-03-2009 12:14 PM

Quote:

Originally Posted by chuckm (Post 137279)
Again, my point is simply that I seriously doubt that 2 hours of hunting could consistently provide meat.

The claim re hunter-gatherer cultures is that about 2 hours a day was/is devoted to gathering food, not necessarily meat. Even here & now, it wouldn't be impossible for someone with the knowledge, especially given the great number of quite edible things that we seldom if ever eat.

Quote:

If it were that easy, why would neolithic man tie up valuable time and resources by working to domesticate cattle and protect them from predation?
To have something to do with all that free time :-) But if you look at the history of domestication, the first domestic animals - dogs, then horses - were probably aids to hunting. Then other animals seem to have been kept as much for milk & wool as for meat.

chuckm 11-03-2009 12:55 PM

Quote:

But if you look at the history of domestication, the first domestic animals - dogs, then horses - were probably aids to hunting. Then other animals seem to have been kept as much for milk & wool as for meat.
In other words, these were enhancements in resource availability and security over simple nomadic hunting-and-gathering.
Quote:

Even here & now, it wouldn't be impossible for someone with the knowledge, especially given the great number of quite edible things that we seldom if ever eat.
I don't disagree, but food availability also varies significantly by region. But would 2 hours of gathering provide for a diet with sufficient caloric and nutritional intake?

Where DOES this 2 hour figure come from anyway? If it is from Sahlins' Notes on the Original Affluent Society, you ought to know that the studies he relied on weren't exactly exhaustive, limited in both scope and duration.

So, anyway, I still think Hansen's figure of 350ppm is not well grounded in scientific fact. I also think his citing 280ppm as "normal" is lacking in context. Don't get me wrong, though; I do believe that we have a moral responsibility to develop and implement clean, efficient and cheap energy sources. But I think that the climate alarmism that Hansen is promoting is ultimately destructive to the cause.

jamesqf 11-03-2009 10:07 PM

Quote:

Originally Posted by chuckm (Post 137493)
Where DOES this 2 hour figure come from anyway? If it is from Sahlins' Notes on the Original Affluent Society, you ought to know that the studies he relied on weren't exactly exhaustive, limited in both scope and duration.

I don't really know. I've seen the figure in various articles, but I don't make a .bib file for my casual reading :-) But there are other accounts of the life of e.g. the various Plains Indian tribes, or the California ones, which certainly support the idea that it wasn't exactly a hand-to-mouth existence.

Quote:

So, anyway, I still think Hansen's figure of 350ppm is not well grounded in scientific fact. I also think his citing 280ppm as "normal" is lacking in context.
I have to agree on the 350 ppm figure, but from the opposite direction. Though it might be tolerable, t's probably too high to allow for a pleasant climate. I'm for 280 at a max - but then I think an ice age might well be an improvement on present conditions. FTM I'd even like to go back to conditions in the late '70s & early '80s, when ski season usually started in October. Some of the immigrants (I regard Californians as immigrants) have complained about this year being cold, but I was out cutting firewood at about 7500 ft yesterday, in a T-shirt.

chuckm 11-04-2009 07:37 AM

Quote:

I have to agree on the 350 ppm figure, but from the opposite direction. Though it might be tolerable, t's probably too high to allow for a pleasant climate. I'm for 280 at a max - but then I think an ice age might well be an improvement on present conditions.
Define pleasant climate... I can tell you that my definition doesn't involve ice ages, resulting in mass starvation, lower biological productivity and such. Honestly, a real return to ice age condition could well wipe out 2 or even 3 billion people.
Quote:

I'd even like to go back to conditions in the late '70s & early '80s, when ski season usually started in October.
I like skiing too. But you do know that back in the 70s, Time had a magazine cover proclaiming climate alarmism of a different form - global cooling. The cover showed an iced over earth, IIRC.

NeilBlanchard 11-04-2009 08:44 AM

If you do not agree that Global Cimate Change is real...
 
What other parts of science do you not believe are true?

Do you believe that the Theory of Gravity is correct? Or, do you believe in Intelligent Falling?

Do you believe in evolution? Or, do you believe in Intelligent Design?

Do you believe in the theory of atomic structure? Or, something else is responsible for how physics and chemistry work?

Do you believe in DNA? Or, do you believe that God chooses what characteristics to give your child?

What about the theory of how the Universe works, and the life cycles of stars and galaxies? Or, do you believe that God created it all in 6 days?

Do you believe that the Earth and the other SEVEN planets are orbiting the Sun? Or, does everything revolve around the Earth?

Is the Earth (approximately) a sphere -- or is it flat?

Do you believe that drugs are developed using scientific methods? Or, are they just lucky guesses?

You see, you can't believe in just parts of science -- it all works the same: we explore the unknown, and as we find out more and more, we theorize about how it works. Then, based on the evidence and peer review, the accepted theory emerges; and is continuously tested and debated. Things settle more, as scientist come into closer and closer agreement.

This is how it is for all scientific endeavors -- they are not just making this up! Global Climate Change is real and it is the predominant scientific conclusion that humans have affected an abrupt change in the climate, by burning old carbon fuels; releasing millions of years worth of old carbon in about 150 years.

A few naysayers here and there may be right -- but on the other hand, maybe the large majority of the scientists who study this are right? Which is the bigger risk: that the naysayers are right and we conserve too much fuel and move to renewable energy anyway -- or, we keep on keepin' on and the ocean rises 40 feet in the next 100 years or so, and parts of the world go into an ice age, other parts go into drought, etc. etc. etc. -- who knows what the risks are??

Are you willing to take that risk?

jamesqf 11-04-2009 11:09 AM

Quote:

Originally Posted by NeilBlanchard (Post 137698)
Do you believe that the Earth and the other SEVEN planets are orbiting the Sun?

Off topic, but a REALLY bad example there, picking a number based on a definition cooked up to give the desired result. There's just no rational basis for concluding that there are eight planets.

As to the rest, I wish people would stop believing things, and start thinking instead.

chuckm 11-04-2009 11:43 AM

Quote:

If you do not agree that Global Cimate Change is real...
What other parts of science do you not believe are true?
NeilBlanchard,
If you remember, in my first response to this thread, I said, "While I do not doubt that global warming is real and it is, to some extent, anthropogenic, I have doubts about how bad moderate warming is."

Regardless of what you or I may believe is the cause, the DATA says the earth has been warming over the past 150 years. Look through my posts... have I said otherwise? Do I think humans have contributed to this warming? Yes, though I do not think that anthropogenic CO2 is the dominant source of warming. Again, let's go to the data. During the Jurassic period, the CO2 level was at 1950ppm. Agreed or not? The earth was 3ºC warmer than present. Agreed or not? But did you catch that? The Jurassic period had CO2 levels 5 times present levels and was only 3ºC warmer! It wasn't 10ºC warmer or even 5ºC warmer, but 3ºC. (Also, life seems to have flourished during the Jurassic period, despite this relative warmth.) The IPCC Special Report on Emission Scenarios predicts that CO2 levels could be 541 - 970ppm by 2100. IOW, the worst case is that CO2 will be 1/2 of what it was in the Jurassic. Agreed or not? Based on those facts, what conclusions could I reasonably reach re: what temps will be like in 2100?

Just because I question the religious fervor surrounding global warming alarmism doesn't mean I am anti-science. Find me one statement that I've made on this thread that demonstrates an anti-science bias. I have gone out of my way to find and reason from a broad base of data, rather than throwing out so-called "fact bombs." You're not-so-veiled attempts above to set science against religion are misplaced. I am a Christian, yes, but I did not remove my brain at the altar.

So again, challenge me on facts. I welcome it.

Quote:

Which is the bigger risk: that the naysayers are right and we conserve too much fuel and move to renewable energy anyway -- or, we keep on keepin' on and the ocean rises 40 feet in the next 100 years or so, and parts of the world go into an ice age, other parts go into drought, etc. etc. etc. -- who knows what the risks are?
Again, I've already stated that I strongly favor the development and implementation of cleaner, more efficient and cheaper energy sources.
Quote:

Originally Posted by chuckm
I do believe that we must work on being better stewards of the Earth and our resources. I do believe that we should develop cleaner and more efficient energy sources. I also believe that cheap, clean and efficient energy sources has the potential to raise billions of people out of poverty - meaning that developing this clean energy is imperative from a humanitarian perspective.

Additionally, since I believe that anthropogenic warming is real (also stated before), I do think that this is another reason we should strive for these non-fossil energy sources. However, I just don't happen to believe it is the crisis Hansen purports.

NeilBlanchard 11-04-2009 05:32 PM

Hi,

The huge majority of all climate scientists think that global climate change is a bad thing, and many of them now know that it is worse than we originally thought. In fact, all the data show that it is accelerating much faster than was thought just a few years ago. We need to let the scientists who study the facts, make their judgments. If we want to dismiss their conclusions, or reinterpret the data, then we are being arrogant.

James Hansen, Lonnie G. Thompson, et al are not making it up.

http://livinggreenbarrie.com/LvGnGlblWarmgIPCCRpt.pdf

As far as the number of planets in the solar system -- this is the decision also made by scientists based on the facts. Pluto is smaller than other objects that we have never called a planet, and it's orbit is pretty strange -- out of the plane and some of the time it is inside Uranus, IIRC.

roflwaffle 11-04-2009 07:07 PM

Quote:

Originally Posted by chuckm (Post 137720)
Again, let's go to the data. During the Jurassic period, the CO2 level was at 1950ppm. Agreed or not? The earth was 3ºC warmer than present. Agreed or not? But did you catch that? The Jurassic period had CO2 levels 5 times present levels and was only 3ºC warmer! It wasn't 10ºC warmer or even 5ºC warmer, but 3ºC. (Also, life seems to have flourished during the Jurassic period, despite this relative warmth.)

If only we could dial back the solar constant on demand! Unfortunately, we can't, and we also can't expect to see the same rise in temperature w/ similar Carbon levels unless we figure out how to turn the sun down, or maybe drop the Earth's albedo. Geo-engineering anyone?

Mustang Dave 11-04-2009 08:16 PM

Quote:

Originally Posted by NeilBlanchard (Post 137772)
...Pluto is smaller than other objects that we have never called a planet, and it's orbit is pretty strange -- out of the plane and some of the time it is inside Uranus, IIRCC.

Yes, Pluto's status has been changed to "minor planet". Sort of a bummer for those who live in the town whose observatory's astronomer discovered Pluto.

Pluto's orbit only intersects the orbit of Neptune. Pluto has never been inside Uranus. ;) Had to say it. :D

chuckm 11-04-2009 08:39 PM

Okay, jamesqf wants me to stop believing things and start thinking instead. NeilBlanchard want me to stop thinking and let the experts do that, saying it is "arrogant" for anybody else to question their conclusions. What to do?

Neil, I assume you are accusing me of being arrogant by disagreeing with these scientists. If it is arrogant to "reinterpret the data," then can you tell me how is that different than a dogmatic and authoritarian religion?

BTW, in reading that report, I happened to notice a GLARING error.
Quote:

Since 1905 the average temperature of the planet, then at 14oC, has increased 2.5%, an unusually rapid rate (a 0.35oC rise). Over the last 25 years, from 1970 to 2005, it went up 4% (or 0.55oC). The total increase in global average temperature represents a rise of 5.4% (or 0.74oC) since 1750.
What's the problem? Simply this: units. They are using Celsius rather than Kelvin. Using Kelvin, 14oC becomes 287K. Recalculating the percentages, using Kelvin transforms the 2.5% into 0.11%. Next, using Kelvin transforms 4% into 0.19%. Finally, the scary 5.4% becomes 0.26%. Why is this important? Because 0oC represents only the temperature at which water freezes, nothing more. Picking that temperature scale only serves to blow the percentages higher. It is a disingenuous and self-serving choice of units.
Quote:

Natural global temperature swings, whether up or down, took millennia to work themselves out. But over time the global climate itself is relatively stable and predictable.
Again, I've already shown that these generalizations are either false (again, the 8.2k event was a drastic 6oC shift that occurred in a 5 year time span) or gross misrepresentations (the Volstok ice cores show 8-10oC variations 5 times in the last 400 years... is that stable?).
Quote:

IPCC scientists say that even if GHG concentrations remain at constant year 2000 levels (which have already been exceeded), the global average temperature will likely rise from 0.3 to 0.9oC per decade.
I find this assertion to be vague and nearly useless. The implication is that temperatures will increase by 0.3-0.9oC every decade forever and ever. Such an implication is ridiculous; at some point, the temperature rise will stop (basic thermodynamics!). Besides, earlier periods with high CO2 concentrations had temperatures that were as stable, though 2-3oC higher, as ours - see above ;) . Instead, they should have said that temperatures will increase by 0.3 - 0.9oC each decade for the next x years. But leaving the blank implication is much scarier.

Again, challenge me with facts. Until I see you present facts, my response to you will be like the French soldier in Monty Python and the Quest for the Holy Grail:
Quote:

Sir Galahad: Is there someone else up there we can talk to?
French Soldier: No, now go away or I shall taunt you a second time.

chuckm 11-04-2009 09:01 PM

Quote:

Originally Posted by roflwaffle (Post 137793)
If only we could dial back the solar constant on demand! Unfortunately, we can't, and we also can't expect to see the same rise in temperature w/ similar Carbon levels unless we figure out how to turn the sun down, or maybe drop the Earth's albedo. Geo-engineering anyone?

Thanks for the link. Let me look through some of the associated papers it links to.


EDIT: As of 11/6, I still have only skimmed two of the linked papers. I've been pretty busy... I should have a little time this weekend.

jamesqf 11-04-2009 09:08 PM

Quote:

Originally Posted by chuckm (Post 137720)
During the Jurassic period, the CO2 level was at 1950ppm. Agreed or not? The earth was 3ºC warmer than present.

Sure, but the problem is that you're creating the unstated assumption that everything else was the same then as now, which is far from being the case. Solar constant, atmospheric pressure & composition, and many other things were different, so not surprising that there might be different results.

jamesqf 11-04-2009 09:16 PM

Quote:

Originally Posted by NeilBlanchard (Post 137772)
As far as the number of planets in the solar system -- this is the decision also made by scientists based on the facts. Pluto is smaller than other objects that we have never called a planet, and it's orbit is pretty strange -- out of the plane and some of the time it is inside Uranus, IIRCC.

No, this was a decision made by a small committee, who cooked up a rather whacky definition of planet specifically to exclude Pluto. Those smaller objects are a few of the moons of the outer planets (which aren't called planets only because they orbit those planets), and the several recently-discovered planet-sized objects outside the orbit of Pluto, which the committee for some reason refuses to accept as planets.


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