Climate Change(d)?

[Loren Pechtel]

Humanity didn't arise halfway through Earth's life, we arose when 99% of the clock was already gone.

And we haven’t even been here for a blip in the life of the earth. Blips could happen again. Why will CO2 levels spike in 50 million years?
Not concerned, just curious.

CO2 levels won't spike--they're going to peg the other way. CO2 levels have been dropping over Earth's history, 50 million years from now is when lowering CO2 can no longer offset the sun getting warmer. Something in the ballpark of a billion years before all life is gone.

 

[Elixir]

Something in the ballpark of a billion years before all life is gone.

If we keep getting smarter maybe we can learn to control our sun’s expansion or build a ringworld or a Dyson sphere or import a new sun and kick the old one out of our galactic arm. If we can’t get it done some time in the next 999 million years it probably wasn’t going to happen anyhow.

 

[steve_bank]

I was not here but the Columbus Day storm is remembered in Seattle.

 

[Jimmy Higgins]

Don't know about records, but this November has been mild.

To date:

• Highs
  • 1 day below average v 15 days above average
• Lows
  • 1 day below average v 10 days above average
  • 6 of the above average days we about or exceeded the average high!

 

[bilby]

We have been having the coldest November in over a decade.

https://www.abc.net.au/news/2024-11-20/queesnland-wet-weather-flash-flooding-to-ease/104621068

 

[Jimmy Higgins]

We have been having the coldest November in over a decade.

https://www.abc.net.au/news/2024-11-20/queesnland-wet-weather-flash-flooding-to-ease/104621068

That is good to hear. Keeps the drop bear attacks down... however, murder slugs love that sort of weather.

 

[Loren Pechtel]

Something in the ballpark of a billion years before all life is gone.

If we keep getting smarter maybe we can learn to control our sun’s expansion or build a ringworld or a Dyson sphere or import a new sun and kick the old one out of our galactic arm. If we can’t get it done some time in the next 999 million years it probably wasn’t going to happen anyhow.

Our getting into the galaxy doesn't mean life will survive on Earth.

 

[Elixir]

Something in the ballpark of a billion years before all life is gone.

If we keep getting smarter maybe we can learn to control our sun’s expansion or build a ringworld or a Dyson sphere or import a new sun and kick the old one out of our galactic arm. If we can’t get it done some time in the next 999 million years it probably wasn’t going to happen anyhow.

Our getting into the galaxy doesn't mean life will survive on Earth.

Yeah. So what? It’s just a rock.

 

[bilby]

Something in the ballpark of a billion years before all life is gone.

If we keep getting smarter maybe we can learn to control our sun’s expansion or build a ringworld or a Dyson sphere or import a new sun and kick the old one out of our galactic arm. If we can’t get it done some time in the next 999 million years it probably wasn’t going to happen anyhow.

Our getting into the galaxy doesn't mean life will survive on Earth.

Yeah. So what? It’s just a rock.

Yeah, but all my cool stuff is there.

 

[Elixir]

Something in the ballpark of a billion years before all life is gone.

If we keep getting smarter maybe we can learn to control our sun’s expansion or build a ringworld or a Dyson sphere or import a new sun and kick the old one out of our galactic arm. If we can’t get it done some time in the next 999 million years it probably wasn’t going to happen anyhow.

Our getting into the galaxy doesn't mean life will survive on Earth.

Yeah. So what? It’s just a rock.

Yeah, but all my cool stuff is there.

If you’re a good boy you can take it all with you.
Waitaminit - “there”?
So you already left?

 

[bilby]

Something in the ballpark of a billion years before all life is gone.

If we keep getting smarter maybe we can learn to control our sun’s expansion or build a ringworld or a Dyson sphere or import a new sun and kick the old one out of our galactic arm. If we can’t get it done some time in the next 999 million years it probably wasn’t going to happen anyhow.

Our getting into the galaxy doesn't mean life will survive on Earth.

Yeah. So what? It’s just a rock.

Yeah, but all my cool stuff is there.

If you’re a good boy you can take it all with you.
Waitaminit - “there”?
So you already left?

Wait... you didn't??

I wondered why I didn't see you at the spaceport.

 

[Elixir]

Something in the ballpark of a billion years before all life is gone.

If we keep getting smarter maybe we can learn to control our sun’s expansion or build a ringworld or a Dyson sphere or import a new sun and kick the old one out of our galactic arm. If we can’t get it done some time in the next 999 million years it probably wasn’t going to happen anyhow.

Our getting into the galaxy doesn't mean life will survive on Earth.

Yeah. So what? It’s just a rock.

Yeah, but all my cool stuff is there.

If you’re a good boy you can take it all with you.
Waitaminit - “there”?
So you already left?

Wait... you didn't??

I wondered why I didn't see you at the spaceport.

SPACEPORT???!
Are you one of those Luddites who’s scared of transporters?

 

[bilby]

Something in the ballpark of a billion years before all life is gone.

If we keep getting smarter maybe we can learn to control our sun’s expansion or build a ringworld or a Dyson sphere or import a new sun and kick the old one out of our galactic arm. If we can’t get it done some time in the next 999 million years it probably wasn’t going to happen anyhow.

Our getting into the galaxy doesn't mean life will survive on Earth.

Yeah. So what? It’s just a rock.

Yeah, but all my cool stuff is there.

If you’re a good boy you can take it all with you.
Waitaminit - “there”?
So you already left?

Wait... you didn't??

I wondered why I didn't see you at the spaceport.

SPACEPORT???!
Are you one of those Luddites who’s scared of transporters?

I am not scared of them; I just recognise that they are explictly suicide devices. That a new me with all the memories of the old me steps out of the other terminal, is no consolation to the me who just got disintegrated.

Also, in a desperate and doomed effort to keep this post on-topic, I refuse to use transporters because of their enormous carbon footprint.

 

[DBT]

Here's another perspective;

Do you think humans will still be around when the continents come back together in 250 million years?
Trust me. You don’t want to be on Earth in about 250 million years when the continents come back together and a new supercontinent forms. And do you know why? Because 250 million years ago, the last time a supercontinent, called Pangaea, formed, Earth had experienced what is pretty much the worst mass extinction in its entire history, the Permo-Triassic Extinction Event, where 90% of all life died. Turns out that the supercontinent itself was responsible for causing the Great Dying, because of the continental configuration’s effect on the climate. Because when all of the Earth’s land is gathered on one hemisphere, leaving the other hemisphere completely covered with water, it pretty much cuts off all existing ocean currents, making the oceans stagnant and starved of oxygen, turning the water black.

And the continents themselves, they became almost completely covered with desert and bubbling tar pits as there is no way for any moisture to reach inland, with most of the moisture coming from the oceans, and the supercontinent preventing atmospheric circulation from bring this moisture to the land. But those volcanoes!

The supercontinent would also result in more severe volcanic activity which would lead to huge amounts of greenhouse gases like carbon dioxide and methane and covering the whole atmosphere with ash and soot and acid rain, resulting in sunlight being blocked out for a really long time, and once this clears up, would result in really rapid global warming.

Pretty scary stuff, isn’t it? And the worst part? Since Earth’s continents are one day going to drift away and form another supercontinent again, the Great Dying may eventually be repeated in the future in approximately another 250 million years, when the continents come back together again. And this will pretty much spell the beginning of the end of all life on Earth that will be caused by the gradual warming and expansion of the Sun 250 million years after that (half a billion years from now).'' - Quora.

 

[bilby]

250 million years?

It took less than a third of that to turn this:



Into this:



It seems implausible that anything we would recognise as human will still be walking the Earth in 250 million years.

This is what the ancestors of humans looked like 250 million years ago:



They might have had some hair, and possibly even mammary glands, though not yet nipples (rather like echidnas today, which secrete milk from a patch of a few hundred slightly specialized hair follicles).

Even assuming (big assumption) that we were FAR slower to change our phenotype in the next 250M years than we were in the last 250M, it is almost certain that we won't look a lot like we currently do - if we avoid extinction for that long.

 

[thebeave]

Here's another perspective;

Do you think humans will still be around when the continents come back together in 250 million years?
Trust me. You don’t want to be on Earth in about 250 million years when the continents come back together and a new supercontinent forms. And do you know why? Because 250 million years ago, the last time a supercontinent, called Pangaea, formed, Earth had experienced what is pretty much the worst mass extinction in its entire history, the Permo-Triassic Extinction Event, where 90% of all life died. Turns out that the supercontinent itself was responsible for causing the Great Dying, because of the continental configuration’s effect on the climate. Because when all of the Earth’s land is gathered on one hemisphere, leaving the other hemisphere completely covered with water, it pretty much cuts off all existing ocean currents, making the oceans stagnant and starved of oxygen, turning the water black.

And the continents themselves, they became almost completely covered with desert and bubbling tar pits as there is no way for any moisture to reach inland, with most of the moisture coming from the oceans, and the supercontinent preventing atmospheric circulation from bring this moisture to the land. But those volcanoes!

The supercontinent would also result in more severe volcanic activity which would lead to huge amounts of greenhouse gases like carbon dioxide and methane and covering the whole atmosphere with ash and soot and acid rain, resulting in sunlight being blocked out for a really long time, and once this clears up, would result in really rapid global warming.

Pretty scary stuff, isn’t it? And the worst part? Since Earth’s continents are one day going to drift away and form another supercontinent again, the Great Dying may eventually be repeated in the future in approximately another 250 million years, when the continents come back together again. And this will pretty much spell the beginning of the end of all life on Earth that will be caused by the gradual warming and expansion of the Sun 250 million years after that (half a billion years from now).'' - Quora.

The creation of the supercontinent Pangaea, via continental drift, was a very slow process. Wouldn't the changes to the climate, ocean currents and the land mass be so slow that the life forms could migrate and/or evolve and adapt to accomodate to the slowly changing conditions. Unlike when the the asteroid killed off the dinosaurs, etc 65 million years ago in the blink of an eye (geologic time scale).

 

[thebeave]

250 million years?

It took less than a third of that to turn this:

View attachment 48601

Into this:

View attachment 48602

It seems implausible that anything we would recognise as human will still be walking the Earth in 250 million years.

This is what the ancestors of humans looked like 250 million years ago:

View attachment 48604

They might have had some hair, and possibly even mammary glands, though not yet nipples (rather like echidnas today, which secrete milk from a patch of a few hundred slightly specialized hair follicles).

Even assuming (big assumption) that we were FAR slower to change our phenotype in the next 250M years than we were in the last 250M, it is almost certain that we won't look a lot like we currently do - if we avoid extinction for that long.

I think that chicken's form factor might have had a little help from man, but your point is taken.

 

[DBT]

Here's another perspective;

Do you think humans will still be around when the continents come back together in 250 million years?
Trust me. You don’t want to be on Earth in about 250 million years when the continents come back together and a new supercontinent forms. And do you know why? Because 250 million years ago, the last time a supercontinent, called Pangaea, formed, Earth had experienced what is pretty much the worst mass extinction in its entire history, the Permo-Triassic Extinction Event, where 90% of all life died. Turns out that the supercontinent itself was responsible for causing the Great Dying, because of the continental configuration’s effect on the climate. Because when all of the Earth’s land is gathered on one hemisphere, leaving the other hemisphere completely covered with water, it pretty much cuts off all existing ocean currents, making the oceans stagnant and starved of oxygen, turning the water black.

And the continents themselves, they became almost completely covered with desert and bubbling tar pits as there is no way for any moisture to reach inland, with most of the moisture coming from the oceans, and the supercontinent preventing atmospheric circulation from bring this moisture to the land. But those volcanoes!

The supercontinent would also result in more severe volcanic activity which would lead to huge amounts of greenhouse gases like carbon dioxide and methane and covering the whole atmosphere with ash and soot and acid rain, resulting in sunlight being blocked out for a really long time, and once this clears up, would result in really rapid global warming.

Pretty scary stuff, isn’t it? And the worst part? Since Earth’s continents are one day going to drift away and form another supercontinent again, the Great Dying may eventually be repeated in the future in approximately another 250 million years, when the continents come back together again. And this will pretty much spell the beginning of the end of all life on Earth that will be caused by the gradual warming and expansion of the Sun 250 million years after that (half a billion years from now).'' - Quora.

The creation of the supercontinent Pangaea, via continental drift, was a very slow process. Wouldn't the changes to the climate, ocean currents and the land mass be so slow that the life forms could migrate and/or evolve and adapt to accomodate to the slowly changing conditions. Unlike when the the asteroid killed off the dinosaurs, etc 65 million years ago in the blink of an eye (geologic time scale).

I guess that harsh conditions of stagnant oceans, vast inland deserts, volcanic activity, etc, is just not conducive to animal or plant life, which is probably why there was an extinction event the last time.

 

[Swammerdami]

Even assuming (big assumption) that we were FAR slower to change our phenotype in the next 250M years than we were in the last 250M, it is almost certain that we won't look a lot like we currently do - if we avoid extinction for that long.

Although vain to speculate on the future evolution of H. sapiens -- even the geopolitical situation a year from now is a big mystery -- it might be fun anyway!

Evolution works surprisingly quickly. Lactase persistence developed independently at least 2 or 3 times as dairy farming made it useful. Here are three claims I've encountered; I wonder which if any are true. In decreasing order of likelihood(?):

• Human brains have gotten smaller over recent millennia: Savages need more intelligence than people nurtured by civilization.
• The Han Chinese succeeded in part due to an "altruism gene."
• Female labor was essential in sedentary farming cultures, but less important in the brutal hunting culture of Scandinavia. Blond Scandinavian women were selected for sexual attraction!

Be grateful that I refrain from speculations about future human evolution. But I hope others indulge.

 

[Swammerdami]

More on-topic is a recent paper ("Recent global temperature surge intensified by record-low planetary albedo") by Helge Goessling.

Abstract
In 2023, the global mean temperature soared to almost 1.5K above the pre-industrial level, surpassing the previous record by about 0.17K. Previous best-guess estimates of known drivers including anthropogenic warming and the El Niño onset fall short by about 0.2K in explaining the temperature rise. Utilizing satellite and reanalysis data, we identify a record-low planetary albedo as the primary factor bridging this gap. The decline is apparently caused largely by a reduced low-cloud cover in the northern mid-latitudes and tropics, in continuation of a multi-annual trend. Further exploring the low-cloud trend and understanding how much of it is due to internal variability, reduced aerosol concentrations, or a possibly emerging low-cloud feedback will be crucial for assessing the current and expected future warming.