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Antarctic sea ice hits lowest minimum on record

nature.com

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Re: Antarctic sea ice hits lowest minimum on record

#91

Post by oceanplexian »

AutumnCurtain wrote: post #51
jtsiskin wrote: post #33

Earlier quoted context omitted.

Ah yes, the “Tens of millions of years ago, the climate was also different!” silly excuse. Modern humans have been around a minuscule fraction of that time. If we are affecting the climate in ways that normally take millions of years, “there’s some plants under the ice” is the non-helpful remark

My family member worked as a petroleum geologist for Exxon-Mobil for many years, and he is fond of talking about how the climate has changed dramatically throughout the earth's history as a sort of defense against any discussion of climate change. That those changes historically went very poorly for the organisms living in affected areas doesn't seem to faze him, as though we should be desirous of a new Permian extin…

I’m not defending Exxon but I feel like no one asks the question “What if we never discovered fossil fuels”.

Well, perhaps Earth would be in the middle of an ice age (And there is evidence to support it) which clearly isn’t good for all the species that would go extinct during such a period. If you look past the alarmism I don’t think we understand this complex system as well as we like to think we do. And that is completely ignoring the massive amount of good things that hydrocarbons do for our planet, help to feed the world, enable humanity to support huge cities and billions of humans, all the modern conveniences of life, and so on.

Re: Antarctic sea ice hits lowest minimum on record

#92

Post by rexpop »

jl6 wrote: post #70
gnatman wrote: post #14

Earlier quoted context omitted.

I just went looking for a map to see how different coastlines would look with a 200m sea level rise. It's, unsurprisingly, significant!! https://www.floodmap.net/

Interesting that even at a ridiculous, unprecedented 500m sea level rise, there are still substantial areas of dry land. It would be a radically different world, and a smaller one for us land based animals, but it doesn’t seem outlandish that civilization could persist.

Dry land is just one aspect of climatic stability. Tolerable and predictable weather patterns is another. Fertile regions, a critical consequence of that. The question isn't whether some will survive, the question is: Who, why them, and at what cost? Furthermore, it's best to avoid population bottleneck scenarios in general, isn't it?

So, sure; we can relax at least our fears for a Kevin Costner "waterworld."

Re: Antarctic sea ice hits lowest minimum on record

#93

Post by LoveGracePeace »

Gravityloss wrote: post #65
ChuckMcM wrote: post #49

Earlier quoted context omitted.

Okay, I'd like to respond to this, " ... you should be more scared, " Can you reason to that position? Here is how I see it, and perhaps that will make my position more clear. I'm going to die (so are you). Every year, the probability that I'm going to die in the next year goes up bit by bit. I don't expect to read articles that continually harp on "look how close to death you are, are you sure you don't want to eat…

Quoted post unavailable.

That is an utter trite, passive aggressive, judgemental and potentially emotionally hurtful response to an eloquently stated position by the parent.

Re: Antarctic sea ice hits lowest minimum on record

#94

Post by LoveGracePeace »

ChuckMcM wrote: post #49
Gravityloss wrote: post #7

Earlier quoted context omitted.

The scientists know this. Paleoclimatology is one big part of climatology. But the outcome is the opposite - you should be more scared, since it shows that climate can change massively. That affects things like agriculture or sea level. What would you assume the sea level was, when those plants were alive? For example, with very quick search: "In general, world oceans were about 100 to 200 metres (330 to 660 feet) hi…

Okay, I'd like to respond to this, " ... you should be more scared, " Can you reason to that position? Here is how I see it, and perhaps that will make my position more clear. I'm going to die (so are you). Every year, the probability that I'm going to die in the next year goes up bit by bit. I don't expect to read articles that continually harp on "look how close to death you are, are you sure you don't want to eat…

Agreed. That was beautifully, logically stated.

Re: Antarctic sea ice hits lowest minimum on record

#95

Post by anonporridge »

jjcon wrote: post #62
anonporridge wrote: post #29

Earlier quoted context omitted.

Ok, you spend your time and resources doing that, and I'll spend mine increasing my military and economic might. Now replace 'you' and 'me' with competing nation states and super powers. It's a kind of geopolitical prisoner's dilemma. We're all screwed to different degrees if we do nothing, but everyone has an incentive to be a parasite, letting 90% of the world use their energy working on this problem that distribut…

I actually think if we had the technology to do that we probably would be, we spend billions on climate research and even on carbon sequestration tech but we just don't have a good scalable way to do it yet.

It's going to cost significantly more energy than the aggregate energy output of all fossil fuel burning over the past 200 years to remove the carbon from the atmosphere that was added. Probably several multiples more because it's harder to undo chemical combustion than to do it.

We're probably talking trillions of dollars, not billions.

Much more likely is that we'd invest a few billion in pumping global coolants into the atmosphere, which could be simpler.

Re: Antarctic sea ice hits lowest minimum on record

#97

Post by jjcon »

r00fus wrote: post #88
jjcon wrote: post #45

Earlier quoted context omitted.

Good to keep in mind that best estimates right now have sea level rising by less than 0.7 meters through 2100. 10 meters may happen some day but it will be a very slow process. https://www.noaa.gov/news-release/us-coastline-to-see-up-to-...

Ecological estimates have been shown to wildly conservative. Who ten years ago had in their ecologic prediction bingo card that we'd have rampant wildfires globally and 118 degree ground temps in the Arctic Circle by 2020?

If you have better sources than the NOAA estimates then by all means provide them, all I see is an unsourced claim and an anecdote

Re: Antarctic sea ice hits lowest minimum on record

#98

Post by klyrs »

ChuckMcM wrote: post #3

I am not a "denier", I can recognize that anthropomorphic activities are changing the climate over time and we're not prepared to deal with that. But this sort of article annoys me because "on record" represents a nanosecond of geologic time. There are mountains, and plant fossils [1] under the ice at Antartica, so at some point in the geologic record there was little to no ice at all! And no humans likely either, wh…

Geology is a funny thing. Those fossils lived 100 million years ago, when Antarctica wasn't even located at the South pole. So, that's a pretty, um, cold comfort.

Found a really neat site for that:

https://dinosaurpictures.org/ancient-earth#105

Also, geological time scales are a bit of a curiosity. Humans are barely a blip. Folks sounding the alarm about climate change are speaking to humans. The Earth will keep turning, and even generalized life on Earth will probably be "fine" as long as we don't tip too far towards a Venus-level greenhouse. Humans might have a rougher go of it.

Re: Antarctic sea ice hits lowest minimum on record

#99

Post by jjcon »

Gravityloss wrote: post #68
jjcon wrote: post #43

Earlier quoted context omitted.

Certainly significant but that also happens on a massive time scale - the best estimates have us up 0.7 meters in 2100. https://www.noaa.gov/news-release/us-coastline-to-see-up-to-...

Unfortunately, that's just linear extrapolation from current rates. Ice sheet collapse can be extremely nonlinear, accelerating rapidly. https://www.nature.com/articles/s41467-018-05003-z.pdf?origi... Or watch any of Eric Rignot's presentations in youtube. The term is Marine Ice Sheet Instability. This video in my opinion gives a fun demonstration of it https://www.youtube.com/watch?v=jLdaAKIkpKA Miscommunicating sea…

False, the long term NOAA models are far more complex than simple extrapolation (though that is of course a part of any forecast) and they certainly aren’t linear. Feel free to read up on them yourself:

https://oceanservice.noaa.gov/hazards/sealevelrise/sealevelr...

Re: Antarctic sea ice hits lowest minimum on record

#100

Post by zsz »

klyrs wrote: post #98
ChuckMcM wrote: post #3

I am not a "denier", I can recognize that anthropomorphic activities are changing the climate over time and we're not prepared to deal with that. But this sort of article annoys me because "on record" represents a nanosecond of geologic time. There are mountains, and plant fossils [1] under the ice at Antartica, so at some point in the geologic record there was little to no ice at all! And no humans likely either, wh…

Geology is a funny thing. Those fossils lived 100 million years ago, when Antarctica wasn't even located at the South pole. So, that's a pretty, um, cold comfort. Found a really neat site for that: https://dinosaurpictures.org/ancient-earth#105 Also, geological time scales are a bit of a curiosity. Humans are barely a blip. Folks sounding the alarm about climate change are speaking to humans. The Earth will keep turn…

That's a cool site! Now to find a continuous / animated -- maybe even 3D -- equivalent thereof.

BTW Venus is outside the Sun's habitable zone (too close to the Sun for liquid water), e.g. https://astrobiology.nasa.gov/uploads/filer_public_thumbnail...

From https://www.planetary.org/articles/what-is-the-habitable-zon.... : "Mercury and Venus are not in the habitable zone because they are too close to the Sun to harbor liquid water. However, evidence suggests that the Sun used to be much dimmer. Venus may have once had oceans, but its proximity to the brightening Sun caused the liquid water to evaporate. The escape of liquid water from Venus’s surface may have directly led to the planet’s current inhospitable, dense atmosphere."

P.S. Hey, that link you provided already /is/ 3D. You can page through the different eras using the left/right arrow keys, but the maps are projected onto a 3D sphere that can be rotated using the mouse.

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