Setting Fire To Sleeping Strawmen (now with extra Toniiiiiiiiiight, you're right, you're right, you're right)
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Unrestrained population growth is exponential [...]
There's no such thing as unrestrained population growth. It's a thing as real as unicorns.
Real world population growth is mostly not unrestrained. The Malthusian model does not apply strongly to reality.
It's never unrestrained and the model does not apply to reality at all.
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The population model, that assumes unrestricted exponential growth.
Ah. See, I've never seen it explained that way. The take-away I got from Malthus's writings is that any population that both grows exponentially and relies on resources constrained to grow linearly will always encounter resource restrictions.
And I don't see how that is wrong, even though it's perfectly correct to point out that fitting an exponential growth curve to historical global human population can't be done in a way that yields much confidence in extrapolations. Human motivations and behaviour turn out to be more complex than those of, say, bacteria (surprise!) and there will always be more factors affecting reproduction rates, both locally and globally, than food availability alone. And as you point out, technological advances do cause hard-to-model discontinuities in food availability.
Be all that as it may: a population with any positive rate of growth and occupying a fixed-size container must eventually suffer from overcrowding in one form or another. Earth's human population currently has a positive growth rate; Earth is a fixed size container; and we are already seeing overcrowding effects - notably, a sudden and profound increase in extinction rates for species we compete with for living space (or, looking at that from a different angle, a distressingly rapid loss of biodiversity).
The fundamental limits to growth here are a genuine problem, and simply shouting "Malthus was wrong! Ehrlich was wrong! Technology is the answer!" won't make that problem go away.
The only thing that will make it go away is for global population to stabilize. In particular, colonizing Mars is not a solution to growth-based overcrowding on Earth.
Consumption doesn't grow exponentially.
Exponentially? Perhaps not quite.
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It's never unrestrained
I think everybody agrees with that.
Really the only important question is how unpleasant the restraints are for those restrained.
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There's no such thing as unrestrained population growth. It's a thing as real as unicorns.
No, but it tends to not last for very long periods of time.
It's been observed in some populations of microorganisms, typically where they've just been pushed through a population bottleneck and dumped in a petri-dish full of perfect food. After that, the colony tends to settle to an equilibrium within its body and an exponential growth front on the edges.
Those circumstances are relatively unusual, but “colony enters comparatively benign virgin territory” has happened in human history too.
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Ah. See, I've never seen it explained that way. The take-away I got from Malthus's writings is that any population that both grows exponentially and relies on resources constrained to grow linearly will always encounter resource restrictions.
Such populations don't exist.
Be all that as it may: a population with any positive rate of growth and occupying a fixed-size container must eventually suffer from overcrowding in one form or another.
No.
The silent assumption that growth rate is fixed is wrong, making the conclusion false.
The only thing that will make it go away is for global population to stabilize.
It will stabilize when it reaches environment capacity. Like it always does.
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It will stabilize when it reaches environment capacity.
My point (and, I believe, Malthus's) is that what looks like "reaching environment capacity" from outside any given population can look pretty fucking miserable from the inside.
To "reach environment capacity" is exactly to have the population's growth rate constrained by resource limits. It seems to me that a forward-looking species such as the one I am allegedly a member of ought to be able to arrange its reproductive affairs in such a way as to leave plenty of environment capacity generally, and biodiversity specifically, in reserve.
It also seems to me that we simply don't understand the ecology of which we are a part well enough to stay safe while fucking with it to the extent that we currently are.
One thing we do understand, having observed countless examples of it in the wild, is that populations that "reach environment capacity" too rapidly tend to degrade their environments badly enough to cause rapid population crashes. I don't particularly want to be part of an environment-degradation-mediated rapid population crash.
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My point (and, I believe, Malthus's) is that what looks like "reaching environment capacity" from outside any given population can look pretty fucking miserable from the inside.
No, Malthus's model depicts a population that travels head first, eyes closed, with constantly increasing speed, until it hits a wall in a grand catastrophe.
It's not how human population grows (or any other animal with same type of reproduction cycle) in reality. The model is plain wrong, and doesn't predict anything useful. That simple fact is known from middle 19th century, when all Malthus's predictions failed and far better model was published. And yet, for over 200 years it stays popular, because it's a great tool for fear mongering.
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It's not how human population grows (or any other animal with same type of reproduction cycle) in reality. The model is plain wrong, and doesn't predict anything useful. That simple fact is known from middle 19th century, when all Malthus's predictions failed and far better model was published. And yet, for over 200 years it stays popular, because it's a great tool for fear mongering.
I've had a theory for a while that certain subjects make the logical parts of our minds short-circuit, and what causes the short-circuit varies from person to person. That's part of why fear-mongering works.
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I've had a theory for a while that certain subjects make the logical parts of our minds short-circuit, and what causes the short-circuit varies from person to person. That's part of why fear-mongering works.
Well, people just like fear, to put it simply. Preparing for the worst is something that helped us, as a species, to survive. You have spare provisions? Prepare for winter. Good crops this year? Store them for bad next year. You have weapons? Arm yourself for neighbor's assault. And so on.
Current times are always worse than past and civilization/world is always crumbling/degrading (famous writings from ancient Egypt come to mind). There's always some general fear of upcoming catastrophe. It was closing judgement day, comet that will end the world, end of millenium or age, depleting food sources (Malthus), global nuclear war, ice age (just 40 years ago), now it's global warming and 'dying Gaia'. Nothing new under the Sun.
What science gave us, is that we can predict real dangers and tell them apart from imaginary ones. Or so it would seem. But simple ideas sound better than complicated ones to general public, and fear is always preferred over soothing messages. Malthus is very simple, easy to grasp by anyone, and it seems correct by intuition. Models that actually correlate with reality are hard, and without the fear factor, just boring.
Now, forget what I wrote above. Give me your vote and your money, and I will fight with overpopulation and global warming. Two for one, it won't be cheaper than that!
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What science gave us, is that we can predict real dangers and tell them apart from imaginary ones.
Give me your vote and your money, and I will fight with overpopulation and global warming. Two for one, it won't be cheaper than that!
I am no longer astounded by those who wrap themselves in the cloak of Science! and then proceed to ignore its most pressing results. Saddened, yes; astounded, no.
Also completely unsurprised to observe that the best funded political operations are always those whose positions support the interests of existing large businesses, regardless of anything negative that science might reveal about the operation of those businesses.
Also also completely, totally and utterly unsurprised to observe that the first resort of the complacent is to project all their own worst characteristics (uncritical acceptance of a particular worldview, dishonest manipulation of public perception to support that acceptance, hypocritical religiosity) onto those pointing to the evidence that change is required.
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For the benefit of interested bystanders without a dog in this fight:
Malthus's model depicts a population that travels head first, eyes closed, with constantly increasing speed, until it hits a wall in a grand catastrophe.
is Julian Simon's strawman paraphrase of Malthus, not Malthus himself.
The imaginary Malthus in Julian Simon's head probably was wrong.
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Also, I'll just leave these here. Draw your own conclusions about whether or not they say the same thing.
It will stabilize when it reaches environment capacity. Like it always does.
[quote=Malthus, book 1, chapter 1]
I.I.4It is observed by Dr. Franklin, that there is no bound to the prolific nature of plants or animals, but what is made by their crowding and interfering with each other's means of subsistence. Were the face of the earth, he says, vacant of other plants, it might be gradually sowed and overspread with one kind only, as for instance with fennel: and were it empty of other inhabitants, it might in a few ages be replenished from one nation only, as for instance with Englishmen.*1
I.I.5
This is incontrovertibly true. Through the animal and vegetable kingdoms Nature has scattered the seeds of life abroad with the most profuse and liberal hand; but has been comparatively sparing in the room and the nourishment necessary to rear them. The germs of existence contained in this earth, if they could freely develope themselves, would fill millions of worlds in the course of a few thousand years. Necessity, that imperious, all-pervading law of nature, restrains them within the prescribed bounds. The race of plants and the race of animals shrink under this great restrictive law; and man cannot by any efforts of reason escape from it.
[/quote]
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Oh, one more thing:
It will stabilize when it reaches environment capacity.
According to the logistic model, population and environment capacity can interact in various ways ranging from stability to chaos.The logistic model is based on the following iterated function
pnew = a × pold × (1 - pold)
where the p numbers express population as a proportion of carrying capacity, and a is an aggregate representing environmental factors generally. If a is under roughly 3, p will stabilise; from 3 to about 3.5 it will display periodicity; above 3.5 it will behave chaotically.
Which is all very well, but the thing about attempting to apply the logistic model to human populations is that we really don't have much of a clue about what the Earth's carrying capacity for human beings is, so any value of p we stick in there is going to be at best an informed guess. Which means we can't reliably curve-fit historical population data to a logistic model in order to derive a. Which means we don't know if the human population is going to stabilize or bounce around with varying degrees of wildness in the long term.
If the logistic model is any good, though, then regardless of a, a value of pold that's very close to 1 will produce within one analysis period a a value of pnew that's very close to 0: the logistic model does not rule out short term population crashes regardless of its long term behavior. So it's in humanity's best interests to stop p from getting close to 1.
Cornucopians seem to think that we can do this without intentionally limiting our growth rate, on the basis that Human IngenuityTM will forever remain capable of increasing the Earth's carrying capacity for human beings regardless of absolute numbers or space constraints. Personally I have no faith that any such increase could ever be sustainable.
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But some models omit too much. They become totally misleading, impossible to use to learn or
predictrestrict anything.A model's value is in how it constrains your anticipation, not in what it allows you to predict.
A model that predicts anything might as well predict nothing.
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Also completely unsurprised to observe that the best funded political operations are always those whose positions support the interests of existing large businesses, regardless of anything negative that science might reveal about the operation of those businesses.
What's ironic is that AGW falls into this category, though most don't realize it. The thing is, if you take AGW seriously, you put carbon caps on everything. Like most regulations, however, it's actually a competitive advantage for large corporations as they can absorb the costs more easily than small businesses can.
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The idea that the amount of funding devoted to persuading politicians to get serious about reducing greenhouse gas emissions is anywhere even close to the amount spent on persuading them not to bother is pretty much the canonical example of an extraordinary claim requiring extraordinary evidence.
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I agree that your shoulder alien should provide evidence of that claim, but my point was that big corporations win either way.
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Like most regulations, however, it's actually a competitive advantage for large corporations as they can absorb the costs more easily than small businesses can.
That's a substantial part of the competitive advantage of large organisations, yes. Did you have a point? If you get rid of regulations altogether, you'll still find that large companies can do better than small ones, though in that case it might be because they can afford larger private security forces…
It's hard to be a small businessman.
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The anti-libertarian straw man thread is
over there.I actually had two points:
- You can't just automatically view regulation as anti-big-corporations. It's not that simple.
- Money isn't the only thing that corrupts science. Power does the job just as well.
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Money isn't the only thing that corrupts science. Power does the job just as well.
What about hard drive failure?
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What about hard drive failure?
By the prior rules, only if the hard drive fails as result of a dodgy power supply.
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Well now, perhaps when someone actually provides real evidence that global warming is actually a threat, as opposed to a bunch of cooked simulations that don't even match reality, it might be worth persuading people to do something about it, instead of just a money transfer.
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Global warming is a threat! You see, when I take this egg and boil it in water, it changes form. I can no longer make an omelette out of it. THAT COULD HAPPEN TO US!
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Yes, but, if you can't make an omelet out of me anymore, isn't that a good thing?
I don't want to be turned into an omelet.
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But do you want to have your head cut off and toast soldiers dipped into your neck?
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@Intercourse said:
No, @boomzilla was arguing that the shitloads of testing are unnecessary, which feeds in to my comment. At least that is how I read his comment.
I don't think that's true. I'm sure the process has many potential improvements in efficiency and so forth. A lot depends on the trade offs that you want to make, like anything else.
I'm just saying that since companies are required by law / regulation to do the testing, they wouldn't bother spending the billions of dollars to do all that testing if someone could simply wait and then reverse engineer their compound and undercut them on price.
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Gotcha. I stand corrected. This is what happens when I try to speak for people.
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The problem is ecology (more accurately, environmental activism) and capitalism collide.
Sort of. Keeping the environment nice is a luxury item, relative to stuff like keeping sheltered and fed. It's when we're actually rich that we care enough to do anything about the environment. Not that there aren't conflicts or anything, but at a big scale, that's the deal.
Stone Age
Obviously, at low enough levels of population and wealth, we simply can't do enough damage to really matter much.
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The idea that the amount of funding devoted to persuading politicians to get serious about reducing greenhouse gas emissions is anywhere even close to the amount spent on persuading them not to bother is pretty much the canonical example of an extraordinary claim requiring extraordinary evidence.
How much is actually spent persuading them not to bother and who's spending it? I've heard lots of accusations about Big Oil and the like, but no figures or anything to back that up, and plenty of commercials from those companies about how much they're interested in other energy sources.
From everything I've seen, you have the extraordinary nature of this issue completely backwards.
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It seems to me that a forward-looking species such as the one I am allegedly a member of ought to be able to arrange its reproductive affairs in such a way as to leave plenty of environment capacity generally, and biodiversity specifically, in reserve.
I love it when a human assumes they are a logic based organism and not an emotional based one.
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toast soldiers dipped into your neck
You keep your militarist carbohydrates to yourself!
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@CarrieVS said:
toast soldiers dipped into your neck?
You keep your militarist carbohydrates to yourself!
Just for you, replace with: toast peace corps workers.
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That's better. Now get some vegan egg substitute in here and we're sorted.
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[i]Vegan egg substitute[/i]? Watch your mouth unless you want to be hard-boiled and peeled.
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A model's value is in how it constrains your anticipation, not in what it allows you to predict.
A model that predicts anything might as well predict nothing.
I dunno, I kind of like the idea of One Model to Rule Them All, One Model to Find Them, One Model to Regress Them All and in the Error-Term, Forecast Them.
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Vegan egg substitute? Watch your mouth unless you want to be hard-boiled and peeled.
Now you're just egging him on.
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I was only yolking.
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Am I being storked?
Filed under: Community Server 4 evar
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Well, most people in this forum seem to think climate change is somewhere between not real and No Big Deal™, whereas everyone else I've seen on every other website seems to disagree. Man I'm kinda torn on this.
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The climate scientists seem to think it's going to be a big deal and they're the experts. In science careers are made by going against the status quo and being able to back that up with evidence. See Galileo, Pasteur, Einstein, etc. So when all the experts agree and dissenters aren't changing anybody's minds with evidence I'm pretty convinced that the scientists are probably right. At this point it's a fact in the same way that plate tectonics, the big bang and evolution are, which is to say that some knuckleheads still try to deny it.
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convinced that the scientists are probably right.
18 years of no global warming, dude. Arctic ice drastically increased in the last few years. You should consider that they might just be in it for the money, since 40 years ago they were saying the exact same things except that we were going to freeze instead of overheat.
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Well, most people in this forum seem to think climate change is somewhere between not real and No Big Deal™, whereas everyone else I've seen on every other website seems to disagree. Man I'm kinda torn on this.
Careful, if you eggspress political views left of center around here, you may end up with egg on your face.
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The existence or not of climate change is not a political view. It's fucking fact.
The soviets rejected all of genetics because it was "bourgeois pseudoscience". They made their own theories instead, all wrong. When you politicize science you get silly results 100% of the time.
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The existence or not of climate change is not a political view. It's fucking fact.
Yawn. The existence of CAGW becomes more suspect with each month with none recorded.
Oh noes, the temperature might warm up a little bit and be like the Medieval Warm Period. Wouldn't that be awful if we had more arable land?
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18 years of no global warming, dude.
That's noise. The signal being measured is tiny, the noise is huge. You're looking at a tiny part of a noisy graph and thinking you can make decent predictions from that.
I don't think anybody who uses the phrase "global warming" knows any more about the subject than I do which is next to nothing.
Arctic ice drastically increased in the last few years
What did I read recently(ish) about sailing the northwest passage for the first time in forever?
You should consider that they might just be in it for the money
You mean all that oil money? I don't know what money you're talking about. There's probably enough money going around to enable the kind of analysis necessary to debunk climate change if the evidence supported it.
40 years ago they were saying the exact same things except that we were going to freeze instead of overheat
There is so much wrong with this statement.
Who is "they"?
40 years ago morons took "ice ages seem to cycle every 20,000 years" to mean "we're overdue for an ice age! Oh noes!" I don't think scientists actually took that seriously. We're also overdue for an extinction level meteorite impact, the north/south magnetic pole switch, and probably a thousand other "these things happen regularly" events.
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You're looking at a tiny part of a noisy graph and thinking you can make decent predictions from that.
Are you bereft of a sense of irony when you say that?
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There is so much wrong with this statement.
Who is "they"?
All kinds of scientists and others. Heck, it was even featured on the cover of National Geographic.
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I put way too much time into this post, especially because I anticipate it will convince pretty much no one... but it was interesting, so whatever.
18 years of no global warming, dude.
I wonder why you pick 18 years?
Could it be that 1998 (I'm assuming you actually meant 16 years1) was far outside of the long-term mean, and if you move the start point the warming trend reemerges? The majority of pairs of (start,end) points will show a warming trend.
Here's a monthly visualization I cooked up. Below4 you'll find the Python script I cooked it up with; it uses land and sea measurements from NOAA3, which is they data set they say should underapproximate warming. (Really it should moderate temperature changes in general.)
Each pixel in the lower left half represents a comparison of two monthly averages. For a pixel at row coordinate r and column coordinate c (i.e. matrix coordinates not plane coordinates), the pixel represents the how much warmer or cooler the rth month since Jan 1984 is compared to the cth month. Red means warmer, blue means cooler, black means no change. The intensity indicates the degree of change, in a linear scale relative to RGB intensity with 255 being the maximum absolute difference across the time frame. The scaling is done separately for each picture below.
So the bottom few rows represent how much warmer or cooler 2014 has been relative to other years, and the further right you look the more recent your basis of comparison is.
Here is the image:
Now at least to me this looks very red, but I think some of that is a perceptual illusion and maybe blue doesn't stand out as much as I'd like, but it takes too long to generate this image because of WTFness so I was lazy and just inverted the colors in Paint; I think this makes the cooler months much more visible. Now warmer is cyan and cooler is yellow:
Here is the last 20 years (starting Jan '94):
And the last 10 years (starting Jan '04), scaled up 300%:
Only the last of these graphs doesn't show a clear warming trend, and you have to get into the 2000s (about 10 years ago, not 16 or 18) before it doesn't. 1998 was a special year and you should stop citing it; it discredits your arguments.
Here's a graph I pulled from another source4:
Now, this agrees with the last 10 years of my graph; the last 10 years don't show a warming trend. But look at the broader picture of it: there are plenty of deviations that are in the 10-year-long ballpark: a big spike around WW2, decade-long zig-zags in the 70s and 80s, etc. You could even argue that the 90s were a little bit of a spike. But if you look beyond about a decade, the trend becomes clear. (More on predictions later.) So looking at the most recent 10-year period and saying "no warming!" is utterly unconvincing to me, especially as we continue setting temperature records. (Guess what there's a good chance will be the hottest year on record? Hey, it's 2014! Surprise! Not. Remember January's polar vortexes in the US? It was still the fourth warmest on record.)
1 Or your argument becomes even weaker, as 1996 was a pretty cool year, cooler than every year since. In fact, out of the 214 possible comparisons of the global average temperature from a month in 1996 to the same month in a later year, only 12-14 (depending on whether you use land2 or land/sea satellite3 measurements) are not warmer in the later year. That doesn't sound like "no global warming" to me.
2 http://data.giss.nasa.gov/gistemp/tabledata_v3/GLB.Ts.txt; see http://data.giss.nasa.gov/gistemp/ for methodolgy
3 http://data.giss.nasa.gov/gistemp/tabledata_v3/GLB.Ts+dSST.txt
4 http://data.giss.nasa.gov/gistemp/graphs_v3/Here is the Python script. I don't have PIL installed here so I just dump a bunch of ImageMagick commands to standard output, so grab those and run. Note that this takes a really long time. (Like 20 or 30 minutes or something for the 30-year pictures above.) In retrospect it was probably a mistake, especially because I wound up not being able to create the image in one big
convertcommand because it had too many arguments.#!/usr/bin/env python2from __future__ import print_function from __future__ import division import os import sys import itertools import subprocess def read_data(filename): """string -> int list""" data = [] with open(filename, "r") as f: for line in f: fields = line.split() data.extend(int(field) # Year J F M .... D then more fields for field in fields[1:13] if field != "****") print("Read data for", len(data), "months", file=sys.stderr) return data def get_comparison_matrix(month_data): """int list -> int int list""" matrix = [] # This puts the final month/whatever as the row index for index, final_temp in enumerate(month_data): matrix.append([final_temp - initial_temp for initial_temp in month_data]) return matrix def standardize_matrix(matrix): # Note that we don't need abs here because if a-b appears in the # matrix at this point so does b-a abs_max = max(max(row) for row in matrix) print("The maximum absolute difference is", abs_max, "100ths of a degree C", file=sys.stderr) size = len(matrix) for final_time_point in xrange(size): for initial_time_point in xrange(size): if initial_time_point > final_time_point: matrix[final_time_point][initial_time_point] = 0 else: matrix[final_time_point][initial_time_point] /= abs_max def magickize(matrix, output_filename): size = len(matrix) commands = [["convert", "-size", "{dim}x{dim}".format(dim=size), "xc:white", output_filename]] for final_index, row in enumerate(matrix): for initial_index, value in enumerate(row): if initial_index > final_index: continue red_part = value * 100 if value > 0 else 0.0 blue_part = -value * 100 if value < 0 else 0.0 color = "rgb({}%, 0.0%, {}%)".format(int(red_part), int(blue_part)) commands.append(["convert", output_filename, "-fill", color, "-draw", "point {x},{y}".format(x=initial_index, y=final_index), output_filename, ]) return commands def main(): """Usage: dataize.py [--debug-matrix | --debug-magick] -o OUTPUT_FILE INPUT_FILE """ try: # A stack trace is graceful error handling, right? dummy1, dummy2, output_file, input_file = sys.argv dummy2 == "-o" or sys.exit(1) debug = None except ValueError: dummy1, debug, dummy2, output_file, input_file = sys.argv dummy2 == "-o" or sys.exit(1) data = read_data(input_file) matrix = get_comparison_matrix(data) if debug == "--debug-matrix": print("=== Raw matrix ===") for row in matrix: print(row) standardize_matrix(matrix) if debug == "--debug-matrix": print("=== Standardized matrix ===") for row in matrix: print(row) sys.exit(0) magick = magickize(matrix, output_file) if debug == "--debug-magick": for command in magick: print(" ".join("'%s'" % arg for arg in command)) sys.exit(0) print("Removing file if it exists", file=sys.stderr) try: os.remove(output_file) except OSError: pass print("Populating file", file=sys.stderr) for idx, command in enumerate(magick): if (idx+1) % 100 == 0: print("echo '[", idx+1, "/", len(magick), "]'", sep="") print(" ".join("'%s'" % arg for arg in command)) #subprocess.check_call(command) main()On Prediction and Why to Act
OK, now the concessions: I am probably less convinced than the scientific consensus that GW is human-caused. That's concession 1.
Concession 2 is that I'm also not convinced that the predictions are going to be very accurate. I recently listened to the audiobook version of Nate Silvers The Signal and the Noise, and that reinforced that point of view; actual climatologists are often fairly skeptical of the models as well. There's a lot of uncertainty to it.
(That said, please don't say "we can't predict the weather a week from now how can we predict it in 50 years"; that is a painfully dumb argument. If I ask you to predict a coin flip, you'll be wrong about half the time. If I ask you to predict how many heads will come up in 500 flips, you'll be pretty accurate.)
Nevertheless, I still think it's important to act. Despite what conservatives and libertarians think (okay, not really :-)), I don't think that because I like sitting in my loft trying to find ways to make things difficult for corporations, and not just because I don't have a loft.
The reason I think we need to act is that, from my perspective, the potential costs of not doing something and being wrong in that decision are far, far higher than the costs of acting. For example, many glaciers are receding due to the temperature rises over the last century, and glacier meltwater is often used as a water source. If the GW predictions are right, this will cause water shortages for many people; it's entirely conceivable that this will cause significant humanitarian problems. Even if that scenario only has, say, a 10% chance of occurring, the cost will be so dramatic that it's worth spending significant resources in an attempt to prevent.
(For the record, and this is probably clear, I proudly consider myself a liberal on most issues, though not all; and on some issues that are important to me it's actually really not even clear what position, if any, can be said to be liberal or conservative. Things like drug policy and NSA-style privacy issues are unpopular with the mainstream of both parties now but have respectable support from both ends of the spectrum.)
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You should consider that they might just be in it for the money, since 40 years ago they were saying the exact same things except that we were going to freeze instead of overheat.
You mean global cooling?
This hypothesis had little support in the scientific community, but gained temporary popular attention due to a combination of a slight downward trend of temperatures from the 1940s to the early 1970s and press reports that did not accurately reflect the full scope of the scientific climate literature...
There was no scientific consensus in the 1970s that the Earth was headed into an imminent ice age. Indeed, **the possibility of anthropogenic warming dominated the peer-reviewed literature even then**. ... One way to determine what scientists think is to ask them. This was actually done in 1977 following the severe 1976/77 winter in the eastern United States. “Collectively,” the 24 eminent climatologists responding to the survey “tended to anticipate a slight global warming rather than a cooling” (National Defense University Research Directorate 1978). .. ...we conducted a rigorous literature reviewof the American Meteorological Society’s electronic archives as well as those of Nature and the scholarly journal archive Journal Storage (JSTOR). ... The survey identified only 7 articles indicating cooling compared to 44 indicating warming. Those seven cooling articles garnered just 12% of the citations.
From "[The Myth of the 1970s Global Cooling Scientific Consensus][2]" (my emphasis)Arctic ice drastically increased in the last few years.
Skeptic arguments that Antarctica is gaining ice frequently hinge on an error of omission, namely ignoring the difference between land ice and sea ice. ... Antarctic sea ice is gaining because of many different reasons but the most accepted recent explanations are listed below:
i) Ozone levels over Antarctica have dropped causing stratospheric cooling and increasing winds which lead to more areas of open water that can be frozen (Gillet 2003, Thompson 2002, Turner 2009).
and
ii) The Southern Ocean is freshening because of increased rain and snowfall as well as an increase in meltwater coming from the edges of Antarctica's land ice (Zhang 2007, Bintanga et al. 2013). Together, these change the composition of the different layers in the ocean there causing less mixing between warm and cold layers and thus less melted sea and coastal land ice.
Is Antarctica losing or gaining ice?
<p>While the interior of East Antarctica is gaining land ice, overall Antarctica is losing land ice at an accelerating rate. Antarctic sea ice is growing <em>despite</em> a strongly warming Southern Ocean.</p>
(Note the continuing downward trend in Antarctic land ice during the last decade.)
