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Formerly Classified Global Warming Spy Photos Released
An anonymous reader writes "The Obama administration has released more than a thousand intelligence images of Arctic ice, following a declassification request by the National Academy of Sciences. The images feature a 1m resolution, and scientists who have had to base climate models on 15m- or 30m-resolution photos are rejoicing. The photos, kept classified by the Bush administration, show the impact of global warming in the Arctic and the retreat of glaciers in Washington and Alaska."
At least we're winning the battle against something!
"Glaciers are not permanent structures. So what?"
Neither are humans, particularly when they have no fresh water.
And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
Neither are planets.
Oh, right...only since the last ice age.
I'm surprised a resolution of 15m wasn't enough. At the supposedly alarming rate that they are receding, wouldn't you think there wouldn't be such a need for this kind of precision?
Since the summary and article do not mention it, 1m resolution = One Meter Per Pixel.
I had to research that to figure out why a one megapixel resolution was some how magically better than thirty megapixels.
Why was a spy satellite taking snaps of the ice classified? The ice launching an incursion into US territory? Are they afraid the terrible secret of ice will be revealed?
Be you Admins? nay, we are but lusers!
prove he wasnt
I think the idea is that they classify everything by default as they don't want whoever to figure out how good the satellites are, though this is likely the result of bureaucratic inertia, as 1m doesn't seem that impressive.
upon the advice of my lawyer, i have no sig at this time
I thought I was going to see a significant movement in the ice sheets, on the order of 10's or 100's of miles. From what I saw, the rate of decline was statistically meaningless, measured in mere feet. My guess is the previous administration was more concerned with releasing something that would show or capabilities of our spy satellites and not trying to conceal this.
Also there's a lot of surface heating related to loss of ice. The change isn't slight either. The classic test is of coarse laying out black and white cards on a sunny day to see their temperature. The black is drastically hotter than the white. Ground and water are quite dark compared to ice so the increase is disproportionate to the ice loss. Loosing surface area of ice during the summer could equal or exceed warming from CO2 over the next century and it's often ignored in temperature projections. I would assume there was more than military secrecy behind suppressing the images. The goal of the oil lobbyist for some time has been to suppress data until it's too late to keep oil usage high and they've had a lot of influence for the last 8 years. Not that that influence has ended it's just no longer absolute.
...not know what a condom is?
Does the average slashdot crowd?
I guess the usual, it gives away too much about their capabilities, orbits and nobody had made sure there wasn't anything sensitive on that ice. Military intelligence is also a game of economics, even if other nations could find things out for themselves there's no reason giving them free information of any kind.
Live today, because you never know what tomorrow brings
Nor are universes.
Stupid industrial revolution, causing the heat death of the entire universe. What won't mankind destroy?
The pictures aren't OF ice, ice just happens to be in them. The pictures are OF boats/subs/etc. The idea is that they're old enough that no one cares that we knew where that cruiser was 10 years ago.
The great irony of the glacier retreat being the harbinger of doom for humanity is that on most continents the glacial retreat is uncovering substantial quantities of archaeological evidence. I wonder what the people whose archaeological evidence we are finding thought about the glaciers when they encroached on their lives thousands of years ago. It is an interesting juxtaposition.
Man -- I was about to mod you up till you hit on the racist BS. Overbreeding is rampant everywhere.
The fact is, the single most polluting thing a person can do is have kids. I'm intentionally child free so in the balance of things, I could drive a hummer, alone, with extra lead weights in the back, 100 miles per day. I could leave my lights on 24/7, run AC to frigid temps in the summer, blast the heat in the winter, keep a propane flare burning ten feet tall day and night in the back yard, and still not come close to the devastation caused by parenthood.
I don't actually live my life that way, because I'm a bit frugal. What mystifies me is why words such as "conservation" and "conservative" have such differing application when both imply frugality to me -- frugality in how we use environmental resources, and frugality in how we use financial resources. I want to see the birth of the frugal party. Pun intended.
What changed under Obama? Nothing Good
Glaciers are like batteries. With a battery, you can store up power when you are near an outlet, so you can continue to operate your device later when you aren't near an outlet. This allows continuous operation irrespective of your proximity to a receptacle.
Glaciers store up water in the form of ice during the winter. Then, in summer when precipitation is less frequent, they melt and release that water. This allows continuous access to water irrespective of the immediate level of precipitation.
Yes, we could build more reservoirs, but talk about expense. Plus they suffer silting issues and large areas have to be destroyed to build them. And if the rains stop falling anyway, then what? Build more?
What changed under Obama? Nothing Good
I don't know if you intended the strawman or not, but allow me to debunk it anyway.
Yes, humans have lived in warmer climates with less glaciers, and colder climates with more glaciers.
There were also a hell of a lot less of them.
The danger of global warming/climate change has never been a threat to the overall existence of humanity (aside from ranting hyperbolic morons). It is however a threat to the maintenance of modern civilization if it causes enough damage to agricultural yields (whether or not it will do this is debatable, and very very complicated).
There is also a big difference between glaciers or rising oceans encroaching on ancient human settlements and them encroaching on our relatively immobile modern cities.
We hope your rules and wisdom choke you / Now we are one in everlasting peace
Generally speaking, there's supposed to be at least a few of them which aren't melting away to nothing."
In who's reality? I live in the arctic, the glaciers are all receding with each passing year.
Anyone that says global warming isn't happening is ill informed. All you have to do is visit places like Alaska and see for yourself.
"Suppose you were an idiot...and suppose you were a member of Congress...but I repeat myself." Mark Twain
Since when is bush-bashing not legit?
We hope your rules and wisdom choke you / Now we are one in everlasting peace
Actually no it doesn't disagree with him at all. There is less surface area (extent) but considerably more volume which has more than compensated for the extent reduction. The total volume of the ice pack has increased not decreased
Where did I go crazy? Where did I call him a denier? Where am I a zealot? Please point out the zealotry.
The whole point of the line you quoted was my acknowledging the exact opposite of what you're accusing me of claiming--that the OP may very well be a reasonable person who did not imply what I saw in his post.
My concern however was that other people would see the implication and think it was a valid point (again, a point the OP may very well never have even thought of, he may have just been humorously musing on the juxtaposition, as he put it. In fact, I think this is probably what happened.)
The only one name calling here is you, since you seem to think that I am a "global-warming zealot," when nothing could be further from the truth. I could spend the next thirty minutes of my time explaining my actual opinion on the matter, but it isn't relevant to my point which is: Pot, meet kettle.
(Okay, that was a bit of name-calling by me, but I'm only being cheeky, not vindictive--the thought popped into my head and talking kitchenware amuses me. May it amuse you too.)
How can we explain this logic to a billion zombied eyed smiling customers waiting in line to buy a Nano? I fear that we will be saying "Ta Ta" to the glaciers that feed the many rivers that feed the Ganges.
You're told secret data has been wrestled from the grasp of the corporates and you're given a link. The page presents a pair of images right at the top, unavoidable; seen before anything is even read. Two images; one of vast quantities of ice, the second utterly free of ice. Global Warming has been implicated before you've read word number one.
If you look carefully you might notice one end of a landing strip just inland in both photos. These photos cover very small areas; only a few miles. The caption reads:
Sea ice forms along the coast in the winter, and generally melts or breaks away by mid July. Observations of sea ice position reveal considerable year-to-year variability. Changes in the timing of coastal sea ice breakup and in the location of offshore sea ice have significant local impacts: ecological, biological, and human. This image series portrays changes in the timing of coastal sea ice breakup, and gives information on smaller scale properties of ice. This information recorded over long periods, is required to understand and model the dynamics of sea ice and how changes or trends develop and influence other systems.
In other words these photos are 'evidence' of nothing. Minor, small scale year-to-year variation in ice flow patterns. The use of these photos in this manner is equivalent to claiming that because there was snow on my walk on January 10, 2008, but none on January 10, 2009, my environment has been ruined by Global Warming.
Yet there it is, fed to the reader at the very start of the story; no disclaimer provided. The pair of photos will now be repeated ad nauseam for years on end around the planet. Biden will have a blown up poster of these photos in his town hall kit by Wednesday. Fresh new memes the huckster elite will use goad "The West" into self inflicted poverty; "See? The planet is in peril! Man must be stopped!"
Here is a recent and well researched report on the $79 billion that has been spent by the US government (only) on climate research over the last 20 years. 19 pages and 52 citations. I dare you to read it. Global Warming advocates are not the underdogs. They rule vast quantities of public money.
In almost all other matters you can take it as a given that around Slashdot you will find if not cynics then certainly skeptics. On the other hand if it has a Bush taint, a little anti-business flavor and it's wrapped up in a Global Warming ribbon you people suck it up like hicks at a Benny Hinn sermon.
Lurking at the bottom of the gravity well, getting old
I can't think of a single reason that this information should have been classified. Pictures of ice!
Yes - water we looking for?
Do not mock my vision of impractical footwear
What is this strawman you speak of? And what is it that you're debunking? The post you're replying to, simply points out that receding glacier tends to reveal archeological evidences of earlier humans, and muses of what they may have thought of the glacier change. Your knee-jerk reaction, suspecting alterior motive, is the reason why I call you a zealot.
Fuck systemd. Fuck Redhat. Fuck Soylent, too. Wait, scratch the last one.
You seem to be making a case that the earth is overpopulated. And, by extension, we are poisoning ourselves with our waste products. If so, I'll have to point out that this is indeed a natural process. Check out any laboratory with cultures of bacteria.
Meanwhile - I have to point out that the GP's post seems to have gone over your head, or at least you dismiss his reasoning. The earth has warmed and cooled many times in the past. In fact, the earth has warmed and cooled within recent prehistory. That heating and cooling has taken place despite man's presence, and there is limited and tainted evidence to support the idea that man is causing global warming.
There are multiple places where man has left artifacts that are now being uncovered by melting glaciers. One story in South America shows that previously cultivated land is being exposed. (Sorry, it's late, I'm lazy, google it yourself if you're really interested)
The fact that there are more people today than at any time in history or prehistory may or may not have an impact on global warming. Fossil fuels probably have an impact, but it probably isn't as great an impact as the alarmists would like us to believe.
Face it: global warming and global cooling is a proven recurring fact. Politics isn't going to change that. Nor will any consensus change it. Given time, the world will cool again. The only question is, whether man will be here to witness it.
Let's start some moon colonies, some Mars colonies, and start out to the other planets. That would improve our chances of seeing the earth covered in ice again.....
"Windows is like the faint smell of piss in a subway: it's there, and there's nothing you can do about it." - Charlie Br
*citation needed
The ringing of the division bell has begun... -PF
This is a great example of sensationalized cherry-picked anecdotal evidence...which in reality means nothing. The picture showing ice was taken during an abnormal year. The ice melts away every year, usually in July. It took longer to melt in 2006 thanks in part to their being more than normal amounts of "multi-year" ice shoved down from the arctic that year.
Article (from AP): http://www.redorbit.com/news/science/372343/arctic_ocean_ice_crashes_on_alaska_shores/
Video (from NASA): http://www.nasaimages.org/luna/servlet/detail/nasaNAS~10~10~71195~176482:Ice-Surge-in-Barrow,-Alaska
You seem to be making a case that the earth is overpopulated. And, by extension, we are poisoning ourselves with our waste products. If so, I'll have to point out that this is indeed a natural process. Check out any laboratory with cultures of bacteria.
IF the worst case climate change scenarios are true, then yes that is how I would describe it. And yes, it is a common natural phenomenon. It is still not in our best interest for that to happen. HOWEVER I am not convinced that the worst case scenarios are true--I'm not convinced they aren't true either--I'm fully skeptical on the matter, I just don't know (and no, I don't reflexively trust simplistic surveys of experts--and I unfortunately don't have time to review the extensive literature on the subject, so I will remain skeptical either way).
Meanwhile - I have to point out that the GP's post seems to have gone over your head, or at least you dismiss his reasoning. The earth has warmed and cooled many times in the past. In fact, the earth has warmed and cooled within recent prehistory. That heating and cooling has taken place despite man's presence, and there is limited and tainted evidence to support the idea that man is causing global warming.
I'm not dismissing it at all. I think it is a valid point (I'm also not certain he was addressing it that seriously). But I think it is a mistake to generalize past history where the human population was less than 1 part in 1 thousand, and more importantly division of labour was minimal, to the present.
10,000 years ago nearly every living human was engaged in procuring the necessities of life for themselves.
5,000 years ago we invented civilization--some people grow food, others build houses, others sell used cars. Civilization inherently rests on the presumption that a subset of the population can provide enough food for the entire population.
I'm NOT saying that climate change will make that impossible, but I am saying that the threat is that it MIGHT do so, and that the mere fact that mankind survived climate change in the past doesn't mean that we can support nearly 7 billion people in the future if the climate changes in ways that damage agricultural yields.
Please understand, I'm very (philosophically) skeptical on the matter. I'm not committing to one conclusion or the other (because, frankly, there is not enough data in my hands (key phrase that, in my hands) to prove anything). I am simply explaining the possibilities, the reason (that I think) one should be concerned about them, and cautioning AGAINST jumping to either conclusion without doing the proper, scientific (epistemologically speaking) due diligence.
There are multiple places where man has left artifacts that are now being uncovered by melting glaciers. One story in South America shows that previously cultivated land is being exposed. (Sorry, it's late, I'm lazy, google it yourself if you're really interested)
The fact that there are more people today than at any time in history or prehistory may or may not have an impact on global warming. Fossil fuels probably have an impact, but it probably isn't as great an impact as the alarmists would like us to believe.
First thing: The physics of the greenhouse effect are not disputable (not accusing you of not knowing this, I'm simply placing it into the record of our discussion). If you increase the portion of carbon dioxide in a mixture of oxygen, nitrogen and carbon dioxide the mixture's opacity in the infra-red rises. This is experimentally, and theoretically (from quantum mechanics) verifiable.
Rising atmospheric opacity makes it harder for the incoming heat from the sun to escape out into space. ONE WAY to restore the energy input/output balance is to raise the surface temperature of the atmosphere. It is however, NOT the only way, and that is where there is ample room for discussion, debate and
If you're simply "Questioning the Mainstream", you're missing the point somewhat. The point is not to question something specific; the point is to question everything. Not only should you be sceptic of people who believe that global warming is real and man-made, but also of those who deny this. In fact, what you should do in all cases is not trust anyone, but look at the studies and data yourself, and judge it on sound scientific reasons.
"The Greenland was once actually green." .. Global Warming.
Really? In your life time? You must be really, really old! As far as my history books go, Greenland has been a frozen semi-continent, well, except for now that the ice pack on it is also melting due to rising arctic temperatures,
Okay, I'll be fair about your statement. Once upon a time there were dinosaurs roaming the lands, and probably around that time when Iceland was located near the equator, it was green and lush. Sure, your point has a small bit of value. But completely irrelevant in the context of this thread.
"Suppose you were an idiot...and suppose you were a member of Congress...but I repeat myself." Mark Twain
"I would contend"
Based on what data? I don't really feel like trusting the future of the planet on somebody's hunch, and the data I've seen seems to show that global warming happens, that it is caused by CO2 emissions, and that it is highly likely that mankind at least contributes substantially to the trend.
"that humans have a minor impact on the globe's warming trend."
Small changes can cause huge changes if the system was in balance before the small change was made.
"There are plenty of other things putting out CO2: cows,"
Okay, that I don't understand at all, perhaps somebody can explain this to me, because I think I'm honestly missing something here. As far as I can tell, this whole "cow emission" thing is total bullshit. Cows' farts don't release new CO2 into the atmosphere. They release CO2 that was previously bound by the plants the cows ate, don't they? So it's all just part of the cycle of life. The real problem isn't the CO2 that was bound by plants during the last few decades and is now released again. The real problem is the CO2 that was bound millions of years ago and is now being released again, destabilizing the climate mankind has enjoyed recently.
As far as my history books go, Greenland has been a frozen semi-continent
From Wiki:
From 986 AD, Greenland's west coast was colonised by Icelanders and Norwegians in two settlements on fjords near the southwestern-most tip of the island.[8] They shared the island with the late Dorset culture occupying the northern and eastern parts, and later with the Thule culture arriving from the north. The settlements, such as Brattahlid, thrived for centuries but disappeared sometime in the 15th century, at the time of one given date for the onset of the Little Ice Age.[9] It is debated[who?] whether data from ice cores indicate that between 800 and 1300 AD the regions around the fjords of southern Greenland experienced a mild climate, with trees and herbaceous plants growing and livestock being farmed. What is verifiable is that the ice cores indicate Greenland experienced dramatic temperature shifts many times over the past 100,000 years.
Speaks volumes about how much "climate scientists" believe in their own evidence : Not. At. All. Clearly they believe repression is necessary to sustain the global warming theory (never mind anthropogenic global warming).
It also proves that the grandparent posts were correct in asserting that anyone, no matter how reputable, finding anti-global-warming evidence is attacked. I mean, this guy is right up there with Fermi, Hawking, Feynman and other legends.
I have karma to burn, and the rightwing conservative BS echo chamber on this story's comments is really getting to me...
It's hard to believe in this day and age, that despite overwhelming scientific consensus on anthropogenic climate change, that there are still hordes and hordes of conservatives and fringe dwellers denying climate change.
Given that the scientific method is the gold standard of finding what the closest thing humans can get to absolute truth, and that real scientists (and not right wing fake scientists and shills paid for by various business, conservative and libertarian interests) have a huge burden of proof to justify their stances, it's absolutely ridiculous that anybody should deny climate change at all.
Climate change deniers are not scientists, and if they're scientists, they're weirdos, and certainly not trained climatologists.
Like many on the conservative side of politics, climate change deniers think that gut instincts, opinions and truths are as strong as scientifically proven fact. It's common amongst irrational, religious people to think that the truth is whatever you decide to believe. This is an affliction of the far Left too, although the Left is always called out on it -- the Right are not.
Climate deniers know they're getting thrashed when objective standards scientific inquiry and applied to their stupid and mistaken beliefs. So they've resorted to the slow drip-drip-drip strategy of conservative lying: repeat a lie over and over and over, and you can turn black into white, and lies into truth. They tried this with the lies that led to the Iraq War, and they succeeded -- at the cost of thousands of needlessly wasted lives.
With climate change however, the stakes are much higher, and it's the duty of all normal, rational scientifically-minded people to oppose the right wing lie machine.
"If you're simply "Questioning the Mainstream", you're missing the point somewhat. The point is not to question something specific; the point is to question everything. Not only should you be sceptic of people who believe that global warming is real and man-made, but also of those who deny this. In fact, what you should do in all cases is not trust anyone, but look at the studies and data yourself, and judge it on sound scientific reasons."
Idealy that is correct but you* cannot have expertise (let alone time) to investigate every issue personally at some point (usually in the land of the lobbyists) a critic turns from a skeptic into a cherry-picking conspiracy nut. This is where "consensus" comes in ("consensus" = "The republic of science"), at some point you have to trust other investigators. So you pick investigators with a good track record to be your surrogates, the most credible are public institutions such as the Royal Academy or NAS or a million other well known acronymns.
If every one of those surrogates agrees on a particular point then it's part of a body of tentative "scientific facts" that are the evidence behind such phrases as "science says light and radio waves are the same thing at different frequencies" or "scientists say a comet or asteroid is the likely cause of the new spot on Jupiter".
A scientific education ( when done properly ) helps you to negotiate this mountain of information more easily and gives you a basic framework to the body of knowledge called science. However self education can also do the job, James Randi is one of my favorite skeptics and his only qualifications are in magic.
I'm not a climatologists but I have followed the topic for nearly three decades. I joined "Al Gore's religion" around 1997 (specifically because of the 1997 IPCC reports). Apparently this makes me harder to convince than NAS who in the late 50's warned the US government that AGW was occuring and have not changed their minds since. My logic goes like this...
Science says:
- The globe is warming.
- Most of the warming is due to CO2 emmissions
- Ignoring the problem is not a rational option.
1. Since 1997 I have not seen any convincing contra-evidence to the consesus. Some of it has made me do a lot of research, most of it has simply been old talking points perpetuated by the Heartland Institute and their affiliates.
2. I cannot name one credible scientific institution that disputes any part of the consesnsus.
3. Dyson is the only credible scientist I can name who still disputes part of the consensus. When he publishes his ideas everyone can check them out.
4. The most interesting critisisms come from members of our own "religion". Especially at my cult leader's web site (realclimate.org), they slay a few psuedo-skeptics for breakfast and then spend the day argueing over real questions such as the "missing methane" that was predicted by climate models.
5. Computer model ensembles for defined senarios give accurate but conservative forecasts. ( I have some expertise in FEA computer simulations and the mathematical training to understand the algorithims )
6. I live in SE Australia that according to geologic evidence and recent experience is highly sensitive to a warming climate (natural or otherwise).
7. The fucking North Pole is melting.
*Disclaimer: not "you" personally.
And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
The company I work for has some work in Uzbekistan. Reading up on the CIA page, it says that while there is no official censorship of the media, there is widespread self-censorship. Anyone who does not censor themselves is usually fired or "taken care of." So while there may be no official cabal of Global Warming alarmists, it does not mean there there are no dire consequences for taking a stance against it.
There are many reasons to migrate from fossil fuels, the most compelling being that they're going to run out very soon. The changing climate is also a worry (which we wouldn't want to encourage to change faster than it already is), but it's not the only reason, and the money spent on migrating to alternative energy sources certainly wouldn't be wasted.
Well, the question is, does the increased fuel efficiency actually pay for itself? The thing is, the more efficient you are, the more complex you are. The more complex you are, the more you cost. This relationship between efficiency and cost is exponential due to increased complexity efficiency demands. I put together a simple JavaScript model of this at http://www.treatyist.com/issue1/savetheearth.aspx . Basically, by jiggering the predicted cost of fuel (using gasoline as a baseline), versus, the exponent of increased energy efficiency costs, you can arrive at a number of scenarios where reducing greenhouse gasses actually doesn't pay for itself. If it pays anyone, it also pays the Chinese and the Europeans..
In any case, most models show that even a rather dramatic altering of CO2 emissions will not alter the course of climate change for a minimum of 200 years. Even if we stopped now, the glaciers are still going to melt. The CO2 is already in the air.
This is my sig.
It's clear that you are not well versed in Conservative Science, because you're not being Fair And Balanced. The five basic principles of Conservative Science are as follows:
1) The earth is six thousand years old.
2) Pi equals three.
3) Global warming is not real.
4) Evolution never happened.
5) Cells are people too.
"Fascism should more properly be called corporatism because it is the merger of state and corporate power." -- Mussolini
The word is Skeptic, not Denialist. Denialist is clearly an emotionally loaded word designed to evoke thoughts of Holocaust deniers.
So the flat-worlders are round-world skeptics, huh? When the evidence is overwhelming, that's when a skeptic becomes a denier (or just a nut).
Do you think that the rising temperatures in Greenland and Alaska and the shrinking north pole ice cover are lies? Come on, that's about as retarded and paranoid as the flat earthers. Just look at the pictures, man. They won't ALL be lying to you.
As for money to made with carbon credits, up until now it hasn't exactly worked very well, has it?
As a kid I remember the big catch phrases being acid rain, the ozone layer and, to a significantly lesser degree, global warming. I remember seeing pictures of perfect blue lakes where all the life had been killed off by acidification and being told that the hole in the ozone layer would mean that I'd need to wear SPF 8000 sunscreen when I grew up, unless we did something about it.
So far as I know we cleaned up emissions from cars and factories to combat acid rain, and it's been very effective. I'm not sure why anyone would've thought that scrubbing pollutants out of the air would affect global warming though. CO2 was never getting scrubbed out.
The air conditioner thing you're referring to had to do with CFCs, iirc. CFCs were the primary agent wrecking the ozone layer, punching holes in it over the Arctic and Australia, as well as other places (to lesser degrees).
Acid rain and ozone layer depletion were issues with proximate, easily identifiable and fixable causes. Rain pH, pollutant content and ozone layer thickness are all very easy to measure and demonstrate, compared to global warming. It's difficult to pretend that these are the result of natural oscillations in the climate.
Actually, the ice cap isn't growing (covering more area), its getting thicker, because more moisture is transported to Antarctica as a consequence of warming.
Its, at the same time, also shrinking (covering less area), and recently its also been containing less total ice despite thickening. (Because less of the area is cold enough to have an ice cap, but there is still more moisture transported to the areas that do support an ice cap.)
So?
Short-term variation and long-term trends are two different things. The year to year variation isn't what is important, its the long-term trend that matters. The year-to-year changes are much greater in magnitude. (There have, in fact, been sharp year-to-year increases -- and drops -- in the last few years, but no evidence of a reversal or halt in the long-term trend.)
Temperature measures are also often done lots of places that are not inner cities, including Antarctica. So what?
What?
Okay, so where is your evidence for absolutely no more than 20% of global warming being anthropogenic? And, even if we granted that, wouldn't the effects of global warming still warrant human action to address it even if none of it was anthropogenic?
No, it doesn't, which is why there is a term specifically for global warming with man-made causes, "anthropogenic global warming".
Well, no; the entire ~200,000 years during which H. sapiens has walked the earth has been within the most recent 10% of the (present) Quaternary ice age, including several glacial periods; the last glacial period during the present ice age ended about 10,000 years ago. There were at least four other ice ages in Earth's history, though.
But the current rapid-and-accelerating global warming is not something consistent with the evidence we have of what has occurred in the past, and we have a pretty good understanding that man is causing it and how.