I am as concerned about climate change as anyone. I think it's the most serious problem we face today. But it is very important to keep some perspective here, if for no other reason, so that we who believe this is a serious problem don't lose credibility in the political battles to come.
1. Earth is not going to become Venus. The surface of Venus is hot enough to melt lead, hot enough to completely sterilize the planet. That is not going to happen here even under an absolute worst-case scenario.
2. Homo sapiens is almost certainly not going to go extinct even in a worst-case scenario. We are a very robust species capable of adapting to an extraordinarily wide variety of situations. We are very, very tough to kill en masse. We ourselves have tried to wipe out segments of our own population in the past and barely made a dent. The biggest killer in our history, bubonic plague, barely killed a third of us.
3. What is at risk, and what IMHO is worrisome, is the modern technological civilization we have built for ourselves. Our infrastructure and political systems are highly dependent on a stable climate. If we lose that, would could easily go back to the middle ages. (We probably won't go back to neolithic times because knowledge is also pretty robust, and we will almost certainly be able to keep basic technologies alive. But a Mad-Max type scenario is a real possibility.)
4. Colonizing the moon or other planets won't save us. All extra-terrestrial environments accessible to use with current technology are much harsher than earth will be even in a worst-case scenario. If we and our civilization can't survive here, we can't survive anywhere.
I am surprised you were downvoted. The 4 points you make seem straightforward, and are accurate.
The timeline for economic damage (from global warming) is fairly long. Even in the worst-case scenario, the Earth as we know it is still recognizable for the next 50 years, and all of the seasons and climate patterns remain roughly the same. The major changes will tend to show 50 to a 100 years from now.
Also, I'd like to point out that the increasing acidity of the oceans is a much worse problem, in the long-term, than the warming of the atmosphere. Carbon washes out of the atmosphere, and ends up as acid in the oceans. At current trends, in less than 100 years the oceans will be more acidic than at any point since the Cambrian Revolution. It is not clear that life in the oceans can survive with those levels of acidity (other than organisms that live in volcanic vents and love acid).
I'm not. Many people seem to have lost sight of what downvotes are supposed to mean on HN. They are supposed to mean, "This comment is not constructive." Instead, people use it to mean, "I don't agree with this." So controversial opinions often get downvoted into oblivion rather quickly. It's damned annoying, especially when people don't follow up with any explanation of why they disagree.
> It is not clear that life in the oceans can survive with those levels of acidity
Actually, that's pretty clear. Some kind of life will survive, even if it's just bacteria and jellyfish. Life is incredibly robust. This is exactly the kind of hyperbole that undermines the arguments for policy changes.
This is not to say that acidification is not a serious problem. It is. But not because it will sterilize the ocean. It won't.
I downvoted because the comment wasn't a response to the article, nor did it really seem to be responding to other comments. I agree that many people make the same complaint you do, claiming that many downvoters are simply disagreeing with content. You might want to consider topicality, too.
I would have posted as a child comment, but I saw a lot of those kinds of things in the discussion even at that early stage. That's why I decided to post top-level.
> So controversial opinions often get downvoted into oblivion rather quickly. It's damned annoying, especially when people don't follow up with any explanation of why they disagree.
I'm glad I'm not the only one who's noticing that. There are certain topics - e.g. progressive taxation, Steve Jobs, Apple and socialism - that are impossible to criticise on HN without triggering a flurry of downvotes.
I suspect that some of the life in the ocean _could_ adapt, if they were not also being over-fished (or having their prey over-fished). You need a large population for variations to crop up, and then some period of time for the beneficial variations to spread out. 50-100 years is _breakneck_ speed as far as evolution goes, but if you have an annual-breeding fish then they could get 50-100 generations to adapt. Whales & dolphins may have a bad time though.
This is exactly the kind of hyperbole I'm talking about. Whales and dolphins and fish are not the totality of life in the oceans. There's krill and algae and bacteria and a bazillion other things.
Now, losing whales and dolphins and fish would be catastrophic (IMO). But that is not the same as losing all life. It is not that "some of the life in the ocean could adapt." Life in the ocean (and on land) will adapt, no question about it. It just might not be the kind of life we humans want to see. That is the problem.
Point 3 is the one that matters. We still have the ability to keep our current civilization alive. We don't even have to change our life style at a large scale. Switching from coal and oil to solar and wind should be a no brainer. It is even widely cost-efficient. People, who think that a few windmills are an offensive sight, are not considering how different life for all of us would be, if we do not act in time.
Sure. There are any number of ways that climate change could destroy civilization. It could do it directly. For example, weather could get so extreme that it could directly destroy our infrastructure faster than we can rebuild it. Weather anomalies could destroy our ability to produce enough food to feed everyone. A catastrophic melting of the Greenland ice cap could raise sea levels to the point where all of the world's coastal cities would be inundated, and it could happen much faster than we could rebuild elsewhere (to say nothing of the fact that global commerce currently depends crucially on stable coast lines so we can have ports).
But much more likely is not the direct destruction of civilization, but rather increased political and economic tensions leading to nuclear war. Climate change is going to lead to a global game of musical chairs as the world's powers vie for ownership of what used to be arctic tundra but is soon to be prime farmland, or what used to be polar ice cap and is soon to be rich oil fields. People are already starting to quibble over who owns the northwest passage (is it an international waterway, or does it belong to Canada?) That didn't matter when you couldn't get through because it was filled with ice. When the ice clears and it becomes a prime shipping route, it matters a lot.
>But much more likely is not the direct destruction of civilization, but rather increased political and economic tensions leading to nuclear war.
Ah, I see that you and I actually do agree that the much more likely case is not a Mad Max scenario, and I agree political tension is the greatest danger. The worst case scenario is we see innocent people needlessly die due to the actions of other people--whether it be squabbling over who caused climate change, or over newly found resources it created, or migrations of peoples whose homelands have been destroyed. I really don't want that to happen.
>Weather anomalies could destroy our ability to produce enough food to feed everyone.
That is a good point, and a great reason why we should stop altering the global environment. It may not be that the ability to produce food is destroyed in the long run, but in the short run we struggle to adapt quickly enough to a changing environment--a topic for debate but certainly one for worry. While I concede there's no evidence this will necessarily happen, the fact is we simply don't know what we're doing when it comes to global climate science, and we're historically great at screwing up the planet with unintended consequences. So we should stop.
>weather could get so extreme that it could directly destroy our infrastructure faster than we can rebuild it.
While of course anything is possible, can you link me to scientific evidence that this will happen. Of course, there is in fact evidence that weather extremes will increase, the likelihood of this scenario where we literally cannot sustain infrastructure on the planet anymore, that would require very extreme weather and a loss of current technology (there already exists technology to build infrastructure which can withstand harsh weather and earthquakes).
I don't have a problem with the science, but the doomsday or "Mad Max" alarmist scenarios are not based in science, and that kind of irrational thinking may do more harm than good--leading to even more irrational thinking.
> the much more likely case is not a Mad Max scenario
I'd say Mad Max is the worst case. Possible, but certainly not inevitable. How likely it is depends on what we choose to do (or not do). But we have to stop talking about turning Earth into Venus or destroying all life or even humans going extinct. None of those are going to happen.
> The worst case scenario is we see innocent people needlessly die due to the actions of other people
The worst case scenario is the collapse of modern technological civilization with the resulting deaths of billions of innocent people. The worst case is really, really bad. So arguments like this:
> we simply don't know what we're doing when it comes to global climate science
don't carry a lot of weight with me. It's true that there is a lot of uncertainty. But that uncertainty cuts both ways. We might be erring in either direction, and the consequences of getting this wrong are very, very serious. So we ought to err on the conservative side. Because the only way to know for sure whether the worst case is possible is to actually make it happen.
> While of course anything is possible, can you link me to scientific evidence that this will happen.
No, of course not. But I can probably find some papers that show that it's possible.
The worst case scenario is we see innocent people needlessly die due to the actions of other people
There's a good case to be made that we're in that situation right now. Look at all the migrants fleeing the Syrian civil war (a conflict arguably driven by climate change as crops failed repeatedly in that area). The flow of said migrants has already resulted in a good deal of avoidable death and political conflict, and that's set to rise with the President of Turkey threatening to use flows of desperate people as a political weapon.
I don't have a problem with the science, but the doomsday or "Mad Max" alarmist scenarios are not based in science
A nuclear exchange would put us in Mad Max territory pretty quickly if you ask me. It's one of a number of unlikely but far from impossible scenarios that we should consider.
Oh yes. The Syrian conflict is due to climate change.
NOT to the political instability in the area caused by USA military interventions, that caused the societal destruction of Iraq and Libya and the rise of ISIS;
NOT to the fact that the CIA armed and trained rebels to topple the local government;
NOT to the American obsession that "Assad must go";
NOT to the fact that Israel favours weak neighbours, in order to have an upper hand in regional economics and conflicts (see for example Golan Heights);
NOT to the fact that Saudi Arabia and Turkey would like to replace the Shiite government with a Sunni one and win a proxy war against Iran.
No, it's becauz climate change. A strange one that follows borders very closely, since Israel seems to be doing absolutely fine.
The closest anyone above came to saying the Syrian conflict was due to climate change was "a conflict arguably driven by climate change as crops failed repeatedly in that area". Note the word "arguably" and the words "driven by" rather than "caused by"; the poster acknowledges that it is at most a contributing factor.
> Poor planning and management, wasteful irrigation systems, intensive wheat and cotton farming and a rapidly growing population are straining water resources in Syria in a year which has seen unprecedented internal displacement as a result of drought in eastern and northeastern parts of the country.
> “Population [estimated at 24 million in 2009] growth, urbanization and increased economic activity have contributed to the water crisis, as have climate change and mismanagement of the water sector,” said a local expert, who preferred anonymity.
> Blamed on a combination of climate change, man-made desertification and lack of irrigation, up to 60 percent of Syria's land and 1.3 million people (of a population of 22 million) are affected, according to the UN. Just over 800,000 people have lost their entire livelihood, according to the UN and IFRC.
[...]
> Aid agencies say a sustainable long-term plan for the affected areas is needed. "We need to do studies to identify a disaster risk reduction strategy on how to overcome climate change and have better farming practices," said Awad.
> Most studies currently describe climate change as a “threat multiplier” rather than a direct cause, just one of a host of interconnected factors – like poverty, exclusion of ethnic groups, government mismanagement, political instability and societal breakdown – that drive conflict.
It is incredibly easy to throw in "climate change" at the end of any list of factors to explain this or that event. Indeed, who is ever going to dispute it? Climate change is, by its very nature, everywhere- so everywhere it can be used as an explanation of something.
The links you provide follow this rule, listing many good reasons for the Syrian water scarcity (and not for the Syrian conflict)- such as dramatic population increase (83% increase in 23 years), land and water resources mismanagement, bad economic measures, wasteful agricultural practices- and throwing in climate change in the end, just to be safe.
In general, one could question how much sense does it make to even cite a far and dubious cause like climate change when more obvious causes are perfectly evident. My favourite example was a WHO report which calculated the future global health impact of climate change as an additional 250000 deaths per year. A huge number. And the method to get it was the following: given the current total number of deaths due to diarrohea, malaria and undernutrition (about 7 million deaths yearly- all of which in developing countries, therefore due to poverty and perfectly preventable), multiplying them by 3.5% (the projected impact of climate change on these issues) and voila... an excellent case for spending some 44 trillion dollars to switch from fossil fuels to clean energy. Or not?
You're arguing with people who have a religious view towards climate change. That poster, Smaug123, just came close to justifying the use of nuclear weapons in the other thread to the grandparent comment, don't take them seriously.
You've shown yourself to be insulting. You've shown yourself to argue for a case that the Syrian war is caused by climate change. You read a post where someone took an inflammatory meme out of context, and tries to make sense out of a situation where climate change could lead to nuclear war:
> "Guns don't kill people! People kill people!"
> Having climate change around sure makes it easier for people to work themselves into positions where they have to use the nukes.
And you defended it by insulting my intelligence. I am really not impressed.
I don't think my comment was ignorant at all. It might be that I just have a longer memory than you. In reality the US government gave a guarded but cautious welcome to Bashar Assad when he succeeded his father and carried himself like a reformist for a few years. But when poor harvests - among other factors - led to protests against the Syrian government, said government responded in a very repressive fashion, which in turn stirred up more opposition.
Clearly you think many other factors are more important, but if you think I'm 'dangerously ignorant' for considering food security as a factor then I'm not going to take your input very seriously.
Well, the US government was in excellent terms with Saddam Hussein, when he waged against Iran a war that killed between half a million and a million people.
Then invaded the country and had Saddam captured and killed on a false pretense, causing other 40 thousand deaths and plunging the country into civil war.
In Chile backed the coup of a bloodthirsty dictator that had thousands of opponents killed and tens of thousands tortured.
Is backing right now Saudi Arabia, one of the states with the worst human rights record on Earth, in the military repression of the Houtis rebellion in Yemen.
As for Syria, according to Wikipedia:
"The Assad government opposed the United States' invasion and occupation of Iraq. The Bush administration then began to destabilize the regime by increasing sectarian tensions, showcasing and publicising Syrian repression of Kurdish and Sunni groups, and financing political dissidents."
And "the main Syrian opposition body – the Syrian coalition – receives political, logistic and military support from the United States, Britain and France. Some Syrian rebels get training from the CIA at bases in Qatar, Jordan and Saudi Arabia. Under the aegis of operation Timber Sycamore and other clandestine activities, CIA operatives and U.S. special operations troops have trained and armed nearly 10,000 rebel fighters at a cost of $1 billion a year since 2012."
Thus promoting and fuelling a civil war that has costed so far between 300 and 400 thousand deaths.
>A nuclear exchange would put us in Mad Max territory pretty quickly if you ask me. It's one of a number of unlikely but far from impossible scenarios that we should consider.
Climate change does not and can not create nuclear war. People create nuclear war.
I don't see why. You are ignoring the fact that many people simply don't share your value calculus, and that that group might include people who have control over nuclear weapons.
It's a mistake to assume everyone else has the same priorities and basic values that you do; their actions might seem illogical to you but actually be logical courses of actions if you knew what their starting premises were.
Oh give me a break. You are the very person going around insulting other's intelligence in this topic, telling people that disagree with you that you 'have a better memory than them,' or they 'have bad reading comprehension.'
Go ahead, keep justifying nuclear weapons on the basis of your presuppositions, whatever they are. The truth is given your reputation here, I'm not keen to give you the time of day to let my imagination run wild about what you are supposing if nuclear war is your answer.
> Not sure about that on a couple-of-hundred-years-from-now time-scale.
It's really not possible. Even if you took all of the oxygen and carbon on earth and converted it to CO2 (which is not even remotely possible) you still wouldn't get Venus. Venus's atmosphere is almost 100 times denser than earth, and it's nearly 100% CO2. Venus is also closer to the sun, which isn't the deciding factor, but it certainly helps keep Venus nice and toasty warm.
Look, earth is 4 billion years old, and life has existed for about 3.9 billion of those, give or take a few hundred million years. Environmental catastrophes have come and gone and life has persisted through all of them. But civilization has only existed for 10,000 years or so, and those 10,000 years have been climactically stable. Unusually stable. It is far from clear that civilization can survive climate change. That experiment has never been done.
> it's possible that 90% of humanity dies
Yes, that is definitely possible. Maybe even likely if we stay on the current trajectory.
> you still wouldn't get Venus. Venus's atmosphere is almost 100 times denser than earth, and it's nearly 100% CO2
That extremely high amount of CO2 in the atmosphere of Venus is not the original cause but a consequence of runaway warming. At a few hundred degrees C, the carbon dioxide bound in rocks starts to sublimate into the atmosphere. For example, limestone would go CaCO3 -> CaO + CO2. 10% of all sedimentary rock is limestone so one can see how that leads to a Venus-like atmosphere.
That said, I agree that a Venus scenario doesn't seem to be possible for Earth right now. In this paper published in Nature, even 3000 ppm of CO2 (i.e. all fossil fuels burned) was calculated not to trigger such a thing. It would require more like 30,000 ppm, which is not really breathable atmosphere anymore:
I don't think this is true. Even with an unbreathable atmosphere, some tiny fraction of humans would survive with recycled air, solar power, and greenhouse vegetables.
It's conceivable that climate change could kill 99%+. I would be very surprised if it exterminated us completely.
Not long ago I thought the same thing. We can live on the ISS, so even if there's no oxygen and temperatures will be perpetually 200ºC above current, I'm sure we can construct habitats (even small cities) that could be self-sustaining and live. But here's the catch: these things don't happen instantly. It's not a turn-based RPG where somebody decides one turn to "build self-sustaining, hermetically sealed arks", before these things become an absolute necessity we may have already lost the infrastructural or technological abilities to do so (even the raw materials come from /everywhere/ on Earth these days). Worse yet, when the social-economic inequality is the difference between life and death, I'm sure a lot of people will be very angry. And very angry people do stupid things. So you build an ark to live, but not everyone outside is truly dead yet, I'm very sure these people would like to get in. Destructively.
Most of the articles I've read about this refer to a "tipping point": that we're crossing some line where the behavior of the system will change dramatically. But what are the actual consequences of this? Can anyone on HN explain the real-world effects that this might have, apart from slightly higher sea levels?
I tried searching, but the fluff to substance ratio is so high out there.
The discussion is quite abstract - perhaps that's why it's difficult to grasp. As I understand it, the climate can be regarded as a dynamical system currently existing at a stable equilibrium. I.e. small perturbations to the state tend to be damped. If there's a massive volcanic event, we will have a few cold years, but the climate will return to something familiar.
It's stable, as when you add up all the positive and negative feedback effects, the result is negative. The most important negative comes from the thermal radiation of the Earth into space, which increases with increasing temperature, resulting in more cooling. Methane in Siberian ice is a hypothesised positive feedback effect: higher temperature => more methane => more warming.
If all these effects ever add up to more than 0 (the "tipping point"), the system will no longer be stable, and will travel around until it finds another stable equilibrium. The actual consequences of this are nowhere stated because they are completely unknown. But we're not talking about measuring sea-levels, we're talking a completely different climate (e.g. Venus).
This is the most galling characteristic of climate science: there's no control sample and we are living inside the only test specimen.
As a species, for long-term survival, we have two choices: ensure our survival on Earth, or go elsewhere. There is no certainty that our survival here is assured (and a considerable body of evidence to suggest it may be at risk), and there is no certainty that a mission to develop other planets or non-planetary habitats will succeed. Therefore failure to massively invest in both is to risk destruction of our entire species.
Now recognise that the development of any extraterrestrial environment capable of supporting an independent (i.e. large) human population will require a much deeper understanding of climates (and other ecosystem elements) than we have today.
Put simply: cutting climate research is a gamble with everyone's lives, and let's also go to Mars ASAP and start trying stuff.
And yet we DO have the historical record. I am no climate-change-denier (far from it), but the current concentration of CO2 is far from the historical maximum. We can say with some confidence that the new equilibrium point is not likely to be Venus. Reaching it _is_ going to cause mass extinctions and _will_ have very negative effects for humanity, but the planet has been through this before and is probably going to be okay in timeframes measurably longer than our existence as a species.
In geologic time frames, we are likely to be entering a domain where glaciation entirely disappears, including in Antarctica. The world was last here ~34M years ago, and sea levels were 200ft (60m) higher. I'm sure anyone reading this understands that this will have huge impacts on our day to day, including the drowning of most of the today's population centers.
(If anyone is curious, research the Eocene, the era that likely has the best predictive power for what will be happening to our climate over the next few thousand years). Just imagine it running in reverse, at a greatly accelerated rate.
And if you're wondering how we might avoid this fate, from an engineering perspective we need to recreate something like this: https://en.wikipedia.org/wiki/Azolla_event
So, i agree, not Venus. Not even as difficult as living under water. But the air would be hostile by default. So special equipment and housing would probably be required for long term survival. We'll all be settlers living on an earth-like planet.
co2 material safety data sheet says 5000 ppm is max allowable for an 8 hour work day. [1]
co2 levels (appear to) have a direct impact on cognition [2], specifically strategy and information usage.
Ecoene had levels around 2000ppm. It'll be interesting to see if we overshoot or undershoot. Sensitive people start noticing effects at around 1k, perhaps as high as 2k for insensitive people. 2-5k "Headaches, sleepiness and stagnant, stale, stuffy air. Poor concentration, loss of attention, increased heart rate and slight nausea may also be present." [3]
I don't think there have been any studies of long term exposure to 2k+ ppm (with no recovery time). as far as i know, nobody has to deal with that level of exposure for months or years. It's likely not good. But, as you say, not Venus.
Maybe it's already been written but I would like to read a sci-fi novel where humanity realizes that our atmosphere is at risk and begins a race to capture it. The end result being that the planet's atmosphere is completely sucked up in to massive containers of liquid air. These are controlled by a few entities around the world, i.e. those who were most successful at liquefying air when it was free. Liquid air then becomes the main commodity about which all commerce is based. Who you get your air from determines your social status and vulnerability.
I don't disagree with anything you just said, but many people take "history" to be distinct from "prehistory" (the latter ends and the former begins at the point in time when humans began to keep records of their affairs). So I caution you not to assume people are necessarily being disingenuous when they say something is at a historical high or whatever.
I am having a very hard time understanding any climate scenario that would make Mars more habitable than Earth. Why should we spend a dollar getting to Mars?
In and of itself, the attempt to colonize Mars probably won't do much for the species. The value is in actually going through the paces: developing primary technologies, techniques, protocols, and doing research, especially observing how organisms (ultimately, humans) are affected by extraterrestrial life, etc.
If the worst comes to pass and the species needs to throw a hail mary, I have to think our chances of success would be improved (even if slightly) if we were to have these sorts of details ironed-out in advance.
There's also the terraforming possibility, even though that's still a long, long way away. It may turn out to be easier to create a habitable atmosphere from scratch than to make even relatively small changes to our own, since the Earth already has all these complex feedback loops. There's also not as much margin for error here because, as The Tick would say, this is where we keep all our stuff.
Not going to be a problem in the next 100 years, but ...
Suppose we started to really use Fusion power not just at our current energy needs, but enough to directly warm the planet. There are hard limits on just how much heat per m^2 you can dump before you start to cook the planet.
Such a civilization may prefer low atmospheric pressure and a planet further from the sun simply for cooling.
Nice pointer. And in particular, Figure 2 of the paper you linked, which shows the simple "Lorenz System" orbiting about a state C for a long time, and then transitioning (at a hard-to-predict time) to a far-away state C'.
I believe the tipping point usually refers to the release of Methane trapped in permafrost? Meaning the permafrost melts, releasing methane, and thus triggering a runaway greenhouse effect. Something like Venus.
Release of all the stored methane would not cause the Earth to turn into Venus. We know this because the process has happened several times, and not only did the Earth not become Venus, it did not come anywhere even remotely close. There is no known process by which climate change would render the Earth uninhabitable.
This doesn't mean it's okay. Release of methane has always happened at the same time as major mass extinctions, possibly as the cause of it. It would create massive warming which would make large inhabited parts of the planet much less desirable, play havoc with the biosphere possibly making large areas of farmland unproductive, and in general being a massive economic drain and probably killing a lot of people.
If we talk about the 5 great extinctions on Earth to date, with 96% of life dying out after one of the great methane releases, i think our chances of survival in such an event is minimal. I don't think even a tiny group of humans could retain enough resources and technology to survive the millions of years that would be needed before life regenerates itself.
These are the methane clathrates trapped mostly in the siberian sea (Arctic ocean), where increasing sea temperatures are causing methane to bubble up to the surface in large patches (sometimes 1 sq km in size).
In previous mass extinctions, such as the End of the Permian, 251 million years ago, 96% of species were lost - due to a similar event:
" A cataclysmic eruption near Siberia blasted CO2 into the atmosphere. Methanogenic bacteria responded by belching out methane, a potent greenhouse gas. Global temperatures surged while oceans acidified and stagnated, belching poisonous hydrogen sulfide. "
The other Arctic tipping point is because the ocean absorbs a lot more energy than ice... so once the Arctic loses more ice cover, it will go ice-free and remain that way.
Nobody knows when/if the methane problem will happen. The ice/ocean thing can be modeled.
In Paris climate conference we decided not to rise temperature over 2.8 degrees. If global temperature will rise over 5.5 degrees not the melting of ice will be our biggest problem, crops will die, plankton in seas will die (60% of oxygen production). So the real-world effect will be game over.
I don't understand this statement. How can a conference decide not to raise global temperature over 2.8 degrees? For that matter, is there any scientific evidence that humans can actually take collective action to slow or stop global temperature increases?
It's all well and good to say that if I personally generate less CO2 then I personally will have less impact on temperature rise, but collectively, the impact depends on lots of other people's decisions, on population growth, on animal populations particularly cows. And of course if we are already on a trajectory that will increasingly release methane from clathrates, then what if that dwarfs changes in human activity?
There does seem to be some evidence that things like carbon taxes are mainly a bureaucratic boondoggle to enrich some people and to hide CO2 production by shifting it to some place that people don't look at too closely. We must never forget that bureaucracy drives corruption no matter what the underlying political system is. So if people are truly serious about collective human action to slow CO2 production or reverse it, we must be even more serious about cleaning out corruption at all levels in all countries.
So our options are having civilization collapse, clean up all corruption everywhere before trying anything, or trying something that "some research" says might be ineffective? Seems like that's a pretty easy choice.
No, the temperature has been significantly higher before - to the point that the poles had a tropical climate. Climate change isn't the end of the world, just the end of the world as we know it.
Some species survived and adapted, some didn't. Hey, evolution! The available evidence on the onset/offset for major climatic swings over the last 1 million years does suggest between a 10 - 100 year switching time, probably linked to the global conveyor belt currents switching between different states.
We have a fairly good understanding of the onset of the current inter-glacial. We don't, because ice cores and other information gets progressively harder to read, the further you go back, know all that much about the onset of a glacial period, but it does appear to be fairly quick. (Not Day after Tomorrow quick, but definitely within a lifetime quick.)
We're coming to what would normally be the end of the current inter-glacial, we have record C02 levels, and the gulf stream has been slowing down for the last 20 years. Nobody really knows whats going to happen next - but the UK Met office was apparently sufficiently alarmed to issue a blog post saying absolutely nothing if you read it carefully.
Presumably you've gotten your answer from the follow-ups, the system 'tips over' the edge and goes from being stable (always returning to the mean when the stimulus is removed) to unstable (removing the stimulus doesn't increase stability of the system).
The problem with it as a theme is that we really don't have a good idea of how the climate system operates long term, and by long term I mean geologically long term, not human long term. Even if we had pre-recorded satellite views of the planet and detailed measurements for the last 2,000 years that would be 2.6% of the 75 ky Ice Age cycle, and less than 0.0004% of the 50 My extinction cycle, or .000005% of the planet lifecycle.
For reference, 2.6% of a solar year is 9 days.
Humans measure time in terms of lifetime, its a very natural thing to do and since they typically live 70+ years, if you were to come to someone 9 days after you have first shown up on the planet and said "Can't you see, the temperature is a full 5 degrees warmer than it was when I started taking measurements!" And that human would pat them on the head and say, "Yes, you will see much bigger changes than that as the year goes by, it will get so hot you will will die of heat exhaustion if you stand outside all day without protection, and then later it will get so cold that you would freeze to death." And they aren't afraid and they consider it normal, because they have seen it many times before, over their whole life. But when the same person comes to them and says "The temperature is full 5 degrees warmer than it has been in 2000 years!", the fact that 2,000 years represents 100 - 200 generations of people (depending on how you choose a 'generation') it fills them with fear because nobody they know has ever experienced anything like that, its different, its scary, and its unknown.
Back in the day (we're talking the 60's) climate scientists would say "Gee, all of these geological records show that the climate changes in cycles, from very warm to very cold. And they noticed we were coming up on a time when the cycles suggest the end of the inter-glacial period was nigh and we should be looking for the leading edge of the next ice age.
Anyway, the planet has been warmer than it is now, its been colder, and it has changed with people present and without them present. The tipping point models have the climate becoming irreversibly destabilized after we pass it, what they don't say is what that means. Does it mean the planet gets really hot? does it mean an ice age starts? Nobody knows and the models don't help.
I think it's important to point out that the big problem here is the rate of change of the system, which is now pinned as having been faster than it's ever been in tens of millions of years.
If climate change was slow enough and withheld within the parameters of the chemical processes that biological systems work with, this would be a non-issue. But the rate of change is too high for civilization and for ecosystems to adapt and create the necessary buffers.
Well, since all the ice has been melting in the last decades, even ice that was geological ages old, that seems to indicate this isn't a 'normal' cycle by any means. Its disingenuous to suggest its explained by short human memory - the measurements are real.
"Tipping point" refers to positive feedback loops that you get into above a certain level of ice melt. One is potential methane release, as another commenter pointed out. Another is the reduced albedo of the melted water as opposed to ice - the water will absorb heat from sunshine more easily, and conduct that heat to the ice. There may be more. (Of course, there may also be negative feedback effects I'm not aware of.)
Its speculated that it could effect the Gulf stream which transport allot of warm water to northern parts of the Atlantic, which gives especially the Northern part of Europe a relatively mild climate considering the latitude.
One of the impacts is increased humidity and heat retention in the atmosphere (warmer air holds more water, water holds heat well), with that higher humidity and energy level translating into more severe storms. At this point I'd be very leery of purchasing anything in areas traditionally considered to be in "100 year flood plains" because those hundred years were measured over very different climate conditions and these days it seems like those 1% floods have become more like 10% floods.
One way of visualizing the impact of warming is by thinking of it like a speaker system. If you turn up the volume (adding more energy), does the average position of the speaker cone itself change much? Or is it just the extremes that change? Part of the concern with climate change is similar to that - the baseline temperature is changing upwards in amounts that don't sound that scary (really, what's the big deal about a degree or two?), but what's really going to do the most immediately noticeable damage is going to be the increased dynamic range which may include temporary instances of extreme cold (e.g. Siberia right now) or extreme heat.
Another concern though it breaks the analogy a bit, is whether there's a point at which a peak is such that it causes a permanent change to the whole system. In a speaker analogy, that's a blown speaker (torn cone, coil separation, etc.). In climate change/global warming, that may be thawing methane clathrates undersea (methane locked in the crystalline lattice of ice) or other underground methane reservoirs (e.g. in permafrost) thawing and injecting a temporary massive amount of methane into the atmosphere similar to what happens with CO2 in exploding lakes (which accumulate CO2 as carbonic acid until some event triggers a mass release). That shock of methane will be temporary since methane breaks down relatively quickly, but it's also a very potent greenhouse gas and even a geologically-quick few years of ongoing release may trigger massive changes in a relatively short time - changes that won't go backwards even after the methane degrades, and changes that will trigger massive political instability while they're going on.
Another possible tipping point might be Greenland's ice sheets - melt on them has been accellerating in recent years, and while the sheet is generally more than a mile thick and would take a long time to melt, it doesn't have to all melt to be a problem. In fact, if it all melted, the average sea level change around the world would be somewhere around 20 feet.
(edit: By the way, my reference to a methane "shock" was deliberate - if that happens, the impact may be disturbingly similar to the effect of a chlorine "pool shock" that kills off things in the pool then reverts back to a normal chlorine level as the chlorine breaks down into harmless forms.)
My assumption is that we will see a continued change in the arctic sea ice pattern over the next decade. The effect on weather will be interesting to see, if the arctic isn't all that cold the annual pattern of wind and heat in the northern hemisphere will be very different; how I don't really have any idea. In a complex heat engine if you change the distribution and amount of heat it's not easy to predict what the end result will be.
Of course if we stop studying it everything will go back to normal /s.
Reading that article feels... unsatisfying. I realize they have a technical audience in mind, but all the data crammed into english sentences feels reminiscent of the days when complex math problems were described in words.
I feel like the dense information in that post could be described much more concisely in visual form, and I'm disheartened that it is instead hidden in paragraphs.
I wouldn't say they have a technical audience in mind. Far from it, this is evidently a press release (notice how it says "by Press Office" at the top).
Put simply, they didn't write it for you. The Met Office externally deals primarily with journalists and civil servants, two audiences for which words are a main currency. I can assure you that internally they are not short of propellerheads geeking out on some quite spectacular visualizations.
I think the most bizarre part about it is the structure of this as a report of 'things Ed Blockley said' (or 'added', or 'continued' - I was surprised not to learn that he 'exclaimed' or 'averred' anything), mixed in with a different set of additional facts and figures and context provided by the 'narrator'. It seems we might have been better served to have just had Ed Blockley's contribution unedited and in its entirety, without the contextualizing and narration provided by the reporter. It is possible to copy/paste out all the reported paragraphs attributed to Dr Blockley from the text and get a well written overview of current Arctic climatology.
Currently, all efforts are geared towards reversing climate change. OTOH I feel that we should also be prepared for the ensuing eventuality of climate change, as it is clear that the current civilisation as we know will collapse under dramatic climate change. What can be possibly done to prepare for such an onslaught ? I don't mean something ridiculous like the movie 2012, but engineered ways to deal with the catastrophe that could possibly hit us or our kids generation in the nest 50-100 years.
Either we have to engineer processes that can withstand climate change OR
We have to engineer the human gene to withstand the oncoming onslaught, so even if current processes are gone, we'll be able to engineer new ones to deal with the existing climate.
AND
we prepare underground or space facilities to wait out the aftermath of a nuclear war
We currently have all the means to prevent a catastrophic climate change. But we are not using them. It seems to be controversial to replace coal with wind and solar. How would you expect even more radical engineering project to succeed? Besides, in between would be a collapse of our civilization - something we really should try to prevent.
GCC deniers like to point to growth in Antarctic sea ice. But it's clear that Antarctic shelf ice is collapsing, which will increase glacial outflow.
So why is Antarctic sea ice growing? Explanations seem to focus on changes in weather patterns, such as precipitation and wind.[0] Or perhaps, it's just that they're measuring ice area, and not ice volume. But there seems to be no explanation that's coherent enough to be persuasive. Or is there?
A little thought experiment I Googled up, seeing as I live near a river estuary and have been pondering the effects of sea levels rising for a few years now: http://geology.com/sea-level-rise/
(IIRC the realistic figures are more along the lines of centimetres rather than metres over the next few hundred years, but it's sobering to consider)
In the very, very long run wouldn't it be preferable to retain as much energy within the earth system as possible, instead of letting it float off into space and difficult to ever recapture?
I've never heard that argument. It certainly sounds very cold hearted, at the very least.
No it wouldn't. The Sun has many billions of years left to go before its red giant phase, and in its red giant phase the problem will be way too much heat, not too little. And anyway, heat is lost in timeframes much shorter than billions of years. The Earth is warm now because of radioactive decay on the interior and sunlight shining on the exterior.
It was actually just a question to illicit imaginative thought, it wasn't seriously intended to garner a yes or no answer.
In the Kardashev scale a Type I civilization is able to harness the total energy of its host planet. A Type II civilization can harness the energy of it's neighbouring star.
Some scientists believe that we may be able to reach Type 1 status in a couple hundred years.
>The Sun has many billions of years left to go before its red giant phase, and in its red giant phase the problem will be way too much heat, not too little.
Not necessarily. If we continue to advance technologically the only limiting factor besides scientific progress may likely well be how much energy we can harness and the age of the universe.
Your response is just so out of place in this discussion though. One single second of the Sun's total energy output is enough to fuel the United States' entire annual energy usage for nine million years. Lack of energy is not a problem, and even if it were, worrying about stockpiling energy on Earth right now in such low amounts to survive the heat death of the universe is like the equivalent of giving a few molecules of water to someone in the desert who's dying of dehydration. It's so many orders of magnitude below significance that it's laughable.
We are facing the very real existential crisis of potentially destroying our civilization through climate change before we can even get off this planet. The heat death of the universe untold billions of years in the future doesn't matter one whit if we don't survive to witness it, and anything we do nowadays won't matter at all towards that end anyway.
I just told you that it wasn't a serious question, just one designed to facilitate interesting thought. You missed the point though, the energy posed in the question was not posed as a remedy to survive the end of the universe but to reach Type II civilization. I would suggest you should calm down and let your mind enjoy a little bit of adventurous thought and stop freaking out about the media scare on climate change. The whole climate change business has become like the War on Poverty -- doing more to preserve itself than to actually affect the future for the better.
That's not the problem right now. The problem right now is that either we have too much energy and we can't get it off the Earth fast enough, or we have too little/exactly enough energy but its distribution is so suboptimal that the best we can do is throw the excess into space because the buffers are full.
1. Earth is not going to become Venus. The surface of Venus is hot enough to melt lead, hot enough to completely sterilize the planet. That is not going to happen here even under an absolute worst-case scenario.
2. Homo sapiens is almost certainly not going to go extinct even in a worst-case scenario. We are a very robust species capable of adapting to an extraordinarily wide variety of situations. We are very, very tough to kill en masse. We ourselves have tried to wipe out segments of our own population in the past and barely made a dent. The biggest killer in our history, bubonic plague, barely killed a third of us.
3. What is at risk, and what IMHO is worrisome, is the modern technological civilization we have built for ourselves. Our infrastructure and political systems are highly dependent on a stable climate. If we lose that, would could easily go back to the middle ages. (We probably won't go back to neolithic times because knowledge is also pretty robust, and we will almost certainly be able to keep basic technologies alive. But a Mad-Max type scenario is a real possibility.)
4. Colonizing the moon or other planets won't save us. All extra-terrestrial environments accessible to use with current technology are much harsher than earth will be even in a worst-case scenario. If we and our civilization can't survive here, we can't survive anywhere.