[Halc]

However, the tsunamis would have little effect on the Western Hemisphere.  Which contains the main centres of civilisation - ie Europe and North America.. In these places, the population would not be greatly inconvenienced.

The water hits are the worst actually, vaporizing untold volumes of water, plummeting the entire hemisphere (anything on the same side of the equator as the hit) into a biblical-scale flood and famine. Immediate effects like Tsunamis pale in comparison to the climate impacts.

[CliffordK]

If one is predicting an ocean impact, then one would go into Tsunami protocols.  A lot would depend on the size of the asteroid, but low lying areas would need to be evacuated, as well as potentially a number of islands.

Ships often like to ride out a Tsunami in a deep sea, but given a few days or weeks advance notice, they could also ride it out on the opposite side of the globe.

How long would water vapor remain suspended? Huge rain storms, but potentially short lived.  I suppose it would depend a bit on how much got up into the stratosphere.

[charles1948]

However, the tsunamis would have little effect on the Western Hemisphere.  Which contains the main centres of civilisation - ie Europe and North America.. In these places, the population would not be greatly inconvenienced.

The water hits are the worst actually, vaporizing untold volumes of water, plummeting the entire hemisphere (anything on the same side of the equator as the hit) into a biblical-scale flood and famine. Immediate effects like Tsunamis pale in comparison to the climate impacts.

The vaporised water from a mid-Pacific asteroid impact would descend as mere rain in Europe and North America.

We in the West could easily cope with that.   We wouldn't experience any "Biblical scale flood and famine effects".

Such effects would confined to the East.  And could be mitigated by our sending "Relief Aid" to the unfortunate eastern people..  Thus easing our consciences, and enabling us in the West  to carry on as normal.

Isn't that the way of the world?

[Kryptid]

The vaporised water from a mid-Pacific asteroid impact would descend as mere rain in Europe and North America.

We in the West could easily cope with that.   We wouldn't experience any "Biblical scale flood and famine effects".

Such effects would confined to the East.  And could be mitigated by our sending "Relief Aid" to the unfortunate eastern people..  Thus easing our consciences, and enabling us in the West  to carry on as normal.

Isn't that the way of the world?

A sufficiently large asteroid would scour the ocean floor, throwing countless tons of pulverized rock into the atmosphere and triggering a "nuclear Winter" type scenario.

[evan_au]

However, the tsunamis (from a Pacific impact) would have little effect on the Western Hemisphere.

You obviously don't consider California and Vancouver to be part of the "centers of civilization"...
- Bear in mind that most of our worldwide chip manufacturing capability borders on the Pacific.

The water hits are the worst actually, vaporizing untold volumes of water,

I heard some estimates that the dinosaur-killer asteroid would have left a hole in Earth's atmosphere, and vaporzed silicates from the impact would have been blasted out into space.
- It would have cooled and condensed into billions of tiny meteorites, which would have rained down around the Earth for the next few hours
- This would have heated the surface of the Earth to pizza-oven temperatures for several hours.
- The remains of this deadly rain exists in the geological record in the form of tiny glass spherules, mainly in North America and Pacific
https://ucmp.berkeley.edu/education/events/cowen1b.html

The nuclear winter would have followed, freezing any animals that weren't already baked...

[charles1948]

The vaporised water from a mid-Pacific asteroid impact would descend as mere rain in Europe and North America.

We in the West could easily cope with that.   We wouldn't experience any "Biblical scale flood and famine effects".

Such effects would confined to the East.  And could be mitigated by our sending "Relief Aid" to the unfortunate eastern people..  Thus easing our consciences, and enabling us in the West  to carry on as normal.

Isn't that the way of the world?

A sufficiently large asteroid would scour the ocean floor, throwing countless tons of pulverized rock into the atmosphere and triggering a "nuclear Winter" type scenario.

The "Nuclear Winter" scenario has never been empirically tested.  I doubt that it represents the truth.  It was invented  during the SALT negotiations of the 1970/80's.  To scare people.

Personally, I think that we should not be similarly scared by the prospect of an asteroid impacting the Earth.

The chances are 70/30 that  the asteroid will come down in the sea.   The sea-water will provide an effective shield against the "pulverised rock" that you refer to.  Most of this rock will be never get out of the sea.  So won't be a problem.

If the asteroid hit the land, it would cause some more serious difficulties.  But I'm sure they can be overcome.

We are not mindless dinosaurs, but intelligent human beings!   We're not going to be wiped out by some stupid rock thrown at us.

Please adopt a more positive attitude!
 


.

[Petrochemicals]

The vaporised water from a mid-Pacific asteroid impact would descend as mere rain in Europe and North America.

We in the West could easily cope with that.   We wouldn't experience any "Biblical scale flood and famine effects".

Such effects would confined to the East.  And could be mitigated by our sending "Relief Aid" to the unfortunate eastern people..  Thus easing our consciences, and enabling us in the West  to carry on as normal.

Isn't that the way of the world?

A sufficiently large asteroid would scour the ocean floor, throwing countless tons of pulverized rock into the atmosphere and triggering a "nuclear Winter" type scenario.

The "Nuclear Winter" scenario has never been empirically tested.  I doubt that it represents the truth.  It was invented  during the SALT negotiations of the 1970/80's.  To scare people.

Personally, I think that we should not be similarly scared by the prospect of an asteroid impacting the Earth.

The chances are 70/30 that  the asteroid will come down in the sea.   The sea-water will provide an effective shield against the "pulverised rock" that you refer to.  Most of this rock will be never get out of the sea.  So won't be a problem.

If the asteroid hit the land, it would cause some more serious difficulties.  But I'm sure they can be overcome.

We are not mindless dinosaurs, but intelligent human beings!   We're not going to be wiped out by some stupid rock thrown at us.

Please adopt a more positive attitude!
 


.

Did not the kt asteroid comedown in the sea?

[Kryptid]

The "Nuclear Winter" scenario has never been empirically tested.

For obvious reasons... but the prospect of nuclear winter is far more than just speculation. Models of it have been created, and they lend credence to the idea that nuclear war could indeed cause global temperatures to drop enough to cause us significant problems: http://climate.envsci.rutgers.edu/nuclear/

I doubt that it represents the truth.

Based on what?

It was invented  during the SALT negotiations of the 1970/80's.  To scare people.

Citation needed.

The chances are 70/30 that  the asteroid will come down in the sea.   The sea-water will provide an effective shield against the "pulverised rock" that you refer to.  Most of this rock will be never get out of the sea.  So won't be a problem.

Vaporized water can't stop vaporized rock from getting into the atmosphere.

We are not mindless dinosaurs, but intelligent human beings!   We're not going to be wiped out by some stupid rock thrown at us.

That entirely depends upon how big the asteroid is. A Theia-type impact would kill not only all humans, but all living organisms (including extremophilic microbes kilometers underground). A K-Pg-type impact could still kill many millions, or even billions of people. Even if that didn't make us extinct, it would still potentially represent the largest disaster known to have affected humanity.

Even supervolcano eruptions (like that at Lake Toba tens of thousands of years ago) can cause significant climate change. The K-Pg impact was many orders of magnitude more powerful than that.

Please adopt a more positive attitude!

I'd prefer to adopt a realistic attitude.

Did not the kt asteroid comedown in the sea?

Yes, it did. That's another reason we know that charles is wrong about downplaying the danger of a water impact.

[jeffreyH]

Why wouldn't we just drag Bruce Willis out of bed, stick him in a rocket, and say, "Go do what you did in that film!" Then run like hell.

[CliffordK]

The "Nuclear Winter" scenario has never been empirically tested.  I doubt that it represents the truth.  It was invented  during the SALT negotiations of the 1970/80's.  To scare people.

There is actually empirical evidence for it, and even in recent history.

1816 is known as "The Year Without A Summer".  It is believed to be the result of a massive volcanic eruption of Mount Tambora, causing global cooling the following year.

I'm seeing some estimates of around 100,000 deaths, but today that number could be far greater, perhaps in the millions.  Hopefully not reaching the billions.

[maria123]

The question you have asked has many contradictory answers. Many people immediately say that they would tell the media, relatives and other acquaintances to protect them. But the truth is that if something like this really happens, there will be a huge panic and no one will know how to react to what I heard, in my opinion.

[Alexggf]

Where is admin?
It is important.
Thank.

[evan_au]

Where is admin?

Admin is approaching Earth on an asteroid.

See the websites mentioned above to find out when we will arrive.

[Zer0]

https://www.un.org/en/observances/asteroid-day

https://www.unoosa.org/oosa/en/ourwork/topics/neos/iawn.html



P.S. - Telephone: +43-1-260 60 4950
Fax: +43-1-260 60 5830

[alancalverd]

We are not mindless dinosaurs,

Dinosaurs were far from mindless. They survived in all sorts of environments for about 170,000,000 years and learned to swim, burrow and fly. The big guys even had two brains, making them four times as intelligent as a politician.

The odd thing about their extinction was its completeness. Land animals (including humans) clearly cannot survive major climate change because their environments are not robust and food may disappear quicker than the animals can migrate. But sea creatures can migrate continuously and the ocean environment and ecology are robust and change very slowly. Sharks survived, so we must assume that their prey fish also were not much affected by the dinosaur extinction event. So why did the ocean dinosaurs also die out?     

[charles1948]

We are not mindless dinosaurs,

Dinosaurs were far from mindless. They survived in all sorts of environments for about 170,000,000 years and learned to swim, burrow and fly. The big guys even had two brains, making them four times as intelligent as a politician.

The odd thing about their extinction was its completeness. Land animals (including humans) clearly cannot survive major climate change because their environments are not robust and food may disappear quicker than the animals can migrate. But sea creatures can migrate continuously and the ocean environment and ecology are robust and change very slowly. Sharks survived, so we must assume that their prey fish also were not much affected by the dinosaur extinction event. So why did the ocean dinosaurs also die out?   

Yes, the complete extinction of sea-dinosaurs is puzzling.  They might've been expected to survive, and then gradually evolve into dolphins and whales  That would seem a natural evolutionary process.

However, this process doesn't seem to be accepted by modern science, which claims that dolphins and whales didn't evolve in the sea.

Rather, they evolved from creatures which started out in the sea, then went onto the land, became mammals, then went back into the sea.

Is this fully convincing?

[Kryptid]

Is this fully convincing?

According to the existing evidence, yes. Multiple transitional forms between land carnivores and modern cetaceans are known (ambulocetus, pakicetus and basilosaurus, to name a few).

[charles1948]

Thanks Kryptid.  I just felt vaguely suspicious about the proposed sequence:

1. Sea-living dinosaurs adapt to life on land;
2. Evolve into land-living mammals;
3. Then evolve back into sea-living equivalents of dinosaurs.

This seemed unduly complicated.  From an Occam viewpoint.  However the paleontological evidence in your post is decisive.

[evan_au]

the complete extinction of sea-dinosaurs is puzzling

One of the surprising suggestions from modeling the Yucutan asteroid impact is that there was a very short, intense period where sub-orbital debris rained down over the entire Earth, raising the air temperature to pizza-oven temperatures for a few hours. That would have killed any animal that breathed it.
- Fish and sharks can both stay underwater permanently. Many species survived.
- Some species of turtles and crocodiles also survived - but they have a low metabolism, and can stay underwater for long periods
- Small mammals & dinosaurs in burrows could breathe the air in the burrow for a while
- However, marine dinosaurs were air-breathing, and needed to surface regularly to breathe

Undoubtedly, the subsequent "nuclear winter" and acid rain also contributed to global extinctions; but an initial sharp, short extinction event explains a few things.

[alancalverd]

Plausible, but how come the pizza oven didn't fry all the vegetation too? Mine certainly does!