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Nicole Alderman
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I don't know if this is a controversial question or not, but I didn't know where else to ask, and this seemed the safest place: How much do you think sea level will rise and how fast?

I was reading http://www.permies.com/t/46839/videos/homestead-remote-island-Developing-docu thread and some were saying not to move to the island because of the sea level rising, and Pia Jensen linked to this neat topographical tool: http://geology.com/sea-level-rise/.

I had fun playing around with the tool, seeing that a 60 meter (196 feet) rise in sea level would get me pretty close to the ocean (I live at almost 600 feet above sea level). Could the sea level even rise that fast within our lifetimes? I always thought the sea level was rising at a rather "slow" rate (inches per 10 years, not feet). What are your thoughts and sources? Thank you!
 
Dan Boone
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According to this, if all the ice melted we'd see 216 feet of sea level rise. That's a National Geographic link, and they quote "some scientists" who think it would take at least 5,000 years to melt that much ice. Here's a link polling a bunch of scientists and coming up with estimates of between two feet and six feet of sea level rise by 2100, so your intuition that it isn't thought likely to be fast is a sound one.

However, be aware that there are a ton of scientific uncertainties built into all the models. There are all sorts of potential "black swan" issues. What don't we know about global warming and the possibility of sudden cascades of warming and melting due to feedback loops we can't anticipate? Ocean currents, jet streams, methane clathrates, so many things we don't understand well enough to predict. Really fast melting (many meters of sea rise in our lifetime) isn't something that reputable scientists are predicting with certainty, and my own gut sense is that the probabilities are very low. But nobody really knows.

 
Mike Feddersen
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Dan Boone
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Given that this is a contentious topic, I should remind everybody that even here in the Ulcer Factory we are all still required to be nice, which includes refraining from suggesting that anybody is "less than perfect." Mike, I hope you didn't intend any derision when using a phrase like "all the libs preaching" but it might have been nicer to say something like "all the people predicting".

As for the arctic ice, it's variable depending on weather; the tabloid newspaper you linked to even acknowledged that 2013 was an "unusually cool summer". Climate trends over many years, of course, are not disproved by specific weather events in a particular season. This link shows that in 2014 the arctic ice went back to shrinking, and even the 2013 extent that triggered that tabloid article (1.97 million square miles) is substantially less than the pre-2000 averages, which were in the 2.4-2.5 million square mile range.

What does it all mean? Well, I guess we'll find out!
 
John Wolfram
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Arctic ice melting has no impact on sea level, sort of like an ice cube melting in my iced tea does not change the level of fluid in my glass.
 
Jennifer Richardson
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Mike, my understanding is that while Antarctic ice is indeed increasing (which is weird and contrary to what most models predicted, as far as I know), Arctic ice is still decreasing.

http://nsidc.org/arcticseaicenews/

Also, although I have neither the training nor the time nor the motivation to delve deeply into the raw data and weigh it, and I certainly do not believe science as it is practiced to be totally infallible, it seems a little dismissive to refer to it as just "libs preaching global warming" when the vast majority of climate scientists do believe that anthropogenic climate change is a real thing that is happening. Our sea levels are indeed measurably rising, whatever may be the proximate or ultimate cause.
 
Nicole Alderman
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John Wolfram wrote:

Arctic ice melting has no impact on sea level, sort of like an ice cube melting in my iced tea does not change the level of fluid in my glass.


Hmmm, if this is true, then why is the sea level increasing, even if at a smallish scale? Could all the run-off and impermeable surfaces be leading to a larger ocean? In other words: we're draining our aquifers; the water can't just "disappear;" and if it isn't in the air, rivers or the lakes (or the trees and plants we're replacing with buildings and pavement); then maybe it's filling the oceans. There are only so many places water can go in a closed system, right? (Those places being: animals/people, plants, soil, aquifers, air, bodies of freshwater, ice pack, and the ocean--unless I missed something...) How much sea-level rise could run-off create?
 
Burra Maluca
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I found the information in this link interesting - http://www.skepticalscience.com/Sea-level-rise-due-to-floating-ice.html
 
Michael Cox
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A lot of the confusion with sea level change is caused by local changes affecting local sea levels, while the big debate is about global sea level change.

I spent a week on the Isle of Arran recently... in the period since the last ice age the sea level has changed there by about 100m. You can see wave cut platforms and raised beaches high above the current sea level, and in that area the sea level is still falling by a few cm every hundred years. This was triggered by the last ice age - the sheer weight of ice pushed down the land mass which is slowly bouncing back up now the ice has gone (isostatic rebound).

Coral atolls and other islands respond to sea level changes and grow (slowly!) to meet the water surface. Coral grows between 1cm and 20cm per year depending on variety and conditions. It grows most vigorously just below the surface of the sea and where it is exposed to wave action it stops and breaks down to sand. This is a dynamic process, not a static one, although we tend to see it as such. Infact many islands are sinking as the weight of the new coral forming weighs down the crust beneath, the island sinks slightly and the new coral grows to meet the surface of the water.

River deltas exist because huge quantities of sediment are carried from mountainous areas and deposited. The additional weight also triggers local subsidence so the overall delta sinks and goes from land to marsh, more sediment is deposited and the land is built up again in response.

In many vulnerable areas these local effects are more significant than global issues, and human activity is impacting the natural systems in adverse ways - pollution killing coral, interfering with delta river systems stops sedimentation and soil building etc...
 
John Wolfram
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Nicole Alderman wrote:Hmmm, if this is true, then why is the sea level increasing, even if at a smallish scale? Could all the run-off and impermeable surfaces be leading to a larger ocean? In other words: we're draining our aquifers; the water can't just "disappear;" and if it isn't in the air, rivers or the lakes (or the trees and plants we're replacing with buildings and pavement); then maybe it's filling the oceans. There are only so many places water can go in a closed system, right? (Those places being: animals/people, plants, soil, aquifers, air, bodies of freshwater, ice pack, and the ocean--unless I missed something...) How much sea-level rise could run-off create?

Antarctic ice is on land. Arctic ice is not.
 
Weston Ginther
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Jennifer Richardson wrote:when the vast majority of climate scientists do believe that anthropogenic climate change is a real thing that is happening


Would love to see some hard data for this claim.

If you are referring to the famous "97% of scientists agree" meme that has been circulated for the last few years, then I would suggest you look deeper into that survey.

To begin with, the survey questioned less than 4,000 scientists.

The questions asked of scientists in that specific survey was something to the effect of "Do you believe humans play a role in influencing climate change?"

Now there isn't a single credible scientist out there who denies that the climate is changing or that humans do play a role. The real debate is HOW big of a role do humans play. A glass of water poured into the Mississippi River will have an effect on the total water levels but the effect is trivial. Although that could be classified as a "false analogy" fallacy, I am not trying to prove my point with that statement; merely looking to make clear the perspective I am trying to point out.
 
Zach Muller
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I think what michael cox said really shows how the seas level changing is complicated, nothing is as simple as the earth is warming up and the ice cubes are melting. There are billions of factors that will affect the sea level, so to bank an argument on it like a lot of climate mongers do is lost on a really analytical mind.

Weston Ginther wrote:

Now there isn't a single credible scientist out there who denies that the climate is changing or that humans do play a role. The real debate is HOW big of a role do humans play. A glass of water poured into the Mississippi River will have an effect on the total water levels but the effect is trivial. Although that could be classified as a "false analogy" fallacy, I am not trying to prove my point with that statement; merely looking to make clear the perspective I am trying to point out.


Hey weston i think there is at least some credibility to you analogy of the glass and river, even if it is a false analogy. I would encourage you to go to a coal fired power plant, refinery, or coal mine, maybe your a coal miner i dont know. But when i see those places in action, even given that the world is a big place, i can understand this isnt a glass of water in the river. Nevermind the physical pollution, and destruction, wars etc.... Just seeing how much energy we have available to humanity, we have enough to waste! While earth is not a closed system, it does have a perticular amount of embedded energy in it. (Thanks to the previous eons)

The perspective that humanity is not really even making a dent in the climate is pretty much null in my mind because i am already put off by the energy production methods and useage on the planet. When people say they don't think humans are causing climate damage i just hear an excuse to keep on pillaging habitats and environments for the sake of Sloppy energy production. Maybe the climate isnt affected just yet, but does it really need to be affected before humans realize our energy production/consumption/waste cycle is pathetic, dangerous, and unsustainable? If we notice this as humans and then continue to destroy the very environment we live in what kind of animal will we be? This is why i have completely given up on climate change, because i think it is just a distaction from the imediate reality we face. No one changess when scientists prove that pollution is killing a rare species, or that peoples common practices are damaging the ecosystem, why would proving massive anthropegenic climate change be any different?

Scientists have now come out in Oklahoma saying that the large occurance of earthquakes in the state are indeed caused by recent fracking. Yet we will continue until its made illegal. What!?! Us okies are going to fall into a huge crack in the earth before the world decides if humans are changing the climate. Its going to be one big ironic lol moment, i can see the headlines, " Oklahoma climate change panel dies in fracking earthquake"

When i encounter people clinging to the notion that humanity is having a negligible effect on the planet i cant help but wonder what they see when they look out their eyes.
 
Dale Hodgins
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A good portion of the world's glaciers,  rest on land or on the seabed. When this ice melts,  it raises sea level,  unlike the ice cube in the cup. About 10% of the land is covered in ice.

 Groundwater reserves,  far exceed the amount found in lakes and rivers. There is about 25 times as much water in underground aquifers as in all of the worlds lakes and rivers. Therefore,  the depletion of groundwater reserves has a much greater chance to raise sea level than the draining of ponds and lakes. Rapid run off,  due to the building of hard surfaces and poor agricultural practices, flushes rainwater quickly out to sea,  where it can't sink into the soil.

 The individual farmer can do much to prevent sea level rise,  in his water management practices.
 
Jennifer Richardson
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Hi Weston,

Your criticisms of the particular study you're referring to (I'm not sure which one that is) may be valid; I can't speak to that, except to say that a sample size of 4,000 is actually quite large, and more than sufficient to produce reliable results, provided the statistical analysis is not either doctored or massively incompetent. As for ambiguous or misleading wording, I would have to see the actual framing of the question to judge it.

Regardless, there have been dozens of surveys of climate scientists as well as those in related fields, as well as surveys of the peer reviewed literature, all of which that I'm aware of have turned up a consensus on anthropogenic climate change, many of them somewhere in the 95-98% range, some lower but well over a majority (some with larger sample sizes than the one you mentioned, some with smaller). Some of these address the question you had of "how much of a factor is human activity" versus "is it a factor at all," or "is climate changing" (which it clearly is) and the answer (in my own decidedly non-scientific terms) has consistently been "a big factor, if not the major causative factor."


Here is a convenient Wikipedia summary of the consensus on climate change, if you want to dig into the references:

https://en.wikipedia.org/wiki/Scientific_opinion_on_climate_change


I certainly don't rule out the possibility of confounding factors (such as publishing bias or other forms of discipline) for dissenting scientists, but all the data I have seen and the public positions of all the major scientific bodies do indeed indicate a strong consensus on anthropogenic climate change. As I said in my original comment, I think it's disingenuous and snide to dismiss the entire question of climate change as "libs preaching global warming" as if it has no scientific basis; that doesn't mean I think the consensus is immune to questioning or that there are factors involved that may not be purely scientific (there always are). But unless I am provided with convincing evidence refuting the broad consensus indicated by the data (for instance, surveys of climate scientists or of peer-reviewed literature that show a majority or thereabouts who do not believe human action is a major factor in climate change), I see no reason to dismiss it out of hand or pretend that it doesn't exist. I have seen lists of dissenting scientists, which are intriguing, but essentially meaningless in statistical terms since there's no way to judge how representative their views are as a proportion of their various fields.

 
Joseph Lofthouse
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Because I live in a northern climate at high-altitude, I'd welcome a bit of warming... I love El Niño years, when the South Pacific is a bit warmer, because for me it means milder winters and more moisture. That means better growing conditions for my farm.

 
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