Climate disasters are inevitable?

[magnemoe]

Yearly or quarterly reports. How success is measured in those reports. Investment depending on provable rates of returns. It's easier to sell a short term scheme to investors.

The model of industry currently, is selling the same product to the same customer, again and again. Smartphones - corporations sell essentially the same smartphone to the same customer several times - only a minor variation in specifications each time.

It's more profitable to get 100m customers to want a new smartphone every year, than to increase the global number of smartphone users by 100m.

Similar for other products - domestic appliances are one example, the durability of the average washing machine reached a peak some time before the 1990's, and has declined since. Things are "beyond economic repair", when 99% of the machine is still functional, and could be returned to service. But repair of such is not possible, because of cost to employ someone to repair it, and lack of replacement parts.

Durable machines are "premium" brands, marketed to "premium customers", and sold at huge markup, and can be repaired.

Result is, there is no market for cheap, durable products. It's more profitable to sell disposable items to the same people, again and again and again.

The quarterly reports is a problem, so is the bonuses who reward short term stock increase without looking of the long term income.

Shutting down the developing and the marketing departments saves lots of money short term

So do outsourcing everything.

However less durable appliances is not the industry fault, its our, the 1980 and earlier stuff was many times more expensive than the stuff you buy today.

700$ in 1980 was more than 700$ today, at the same time the technical demands has increase, today it tend to be regulative limits to noise, water and power usage.

Some saving by increasing volume, outsourcing and more robots however quality is also cut.

Other part is that we tend to use washing machines and similar more than we did 30 years ago, exception is single person households who could not afford them 30 years ago.

Power tools are probably more extreme, the cheapest versions is probably 10 times cheaper than the cheapest 25 years ago, yes here quality is horrible, again it depend on usage pattern if you use a drill two times a year you can do with a 60$ one, that is as long as you don't run it to hard, if you do you break it in 10 minutes

Done it multiple times, found it smart to save the recipes to get a new one the the old stuff break.

[KerikBalm]

We have had two real huge extinctions, the one 64 millions years ago and one worse 250 million years ago who is related to the Siberian traps, an volcanic event who generate lava fields like an moon sea is likely to release a lot of co2, the global winter will also kill most plants and give an heat peak after the clouds disappear.

There have been many more than that... the K-T extinction was big... bit it wasn't so big when looking back...

The KT is the last spike...

The end of the cambrian one was bigger (as was the mid cambrian). The end of the triassic was just about as big, as was the end of the oridivician.

And the Permian extinction's causes are more complex than the siberian traps (and I'm not sure what you mean with your moon comparison), and in fact occured in 2 stages. They do thing the siberian traps set off the sequence of events... but that sequence of events involves a burning of a lot of biomass, and later melting of methane hydrates.

I have thought about the implications of all the long lasting habitable planets being on super Earths.... very difficult to get into space... Space ladders become basically imposible (assuming they may be barely possible here on Earth with stuff like super long carbon nanotubes)... the thicker atmosphere makes "space gun" type launches (like maglev tracks, mass drivers, etc) pretty daunting too (they are already daunting on Earth).

You won't get any faster than on earth with scramjets... but you've got to get going even faster... the payload fraction to orbit would be horrendous.

[magnemoe]

There have been many more than that... the K-T extinction was big... bit it wasn't so big when looking back...

http://upload.wikimedia.org/wikipedia/commons/thumb/0/06/Extinction_intensity.svg/531px-Extinction_intensity.svg.png

The KT is the last spike...

The end of the cambrian one was bigger (as was the mid cambrian). The end of the triassic was just about as big, as was the end of the oridivician.

And the Permian extinction's causes are more complex than the siberian traps (and I'm not sure what you mean with your moon comparison), and in fact occured in 2 stages. They do thing the siberian traps set off the sequence of events... but that sequence of events involves a burning of a lot of biomass, and later melting of methane hydrates.

I have thought about the implications of all the long lasting habitable planets being on super Earths.... very difficult to get into space... Space ladders become basically imposible (assuming they may be barely possible here on Earth with stuff like super long carbon nanotubes)... the thicker atmosphere makes "space gun" type launches (like maglev tracks, mass drivers, etc) pretty daunting too (they are already daunting on Earth).

You won't get any faster than on earth with scramjets... but you've got to get going even faster... the payload fraction to orbit would be horrendous.

We had one just as large as K-T 200 million years ago, then two smaller, 40 and 150 milion years ago.

Past 200 million years you have more of them, the baseline extinction rate also look 5 time higher.

The moon sea is how large it was, it was no normal volcano but more an sea of lava, might be caused by an meteorite impact on the other side of earth.

Comparing AWG with it is to pull thing very far. Rather look at other times earth has been very hot and it did not cause any problems.

Permafrost is an relic of the ice age anyway, you don't get it places who has not been under ice and its going away slowly naturally.

How interesting would space be if we first managed to launch our first satellite in 2200? Another Fermi paradox explanation.

[Frozen_Heart]

Is it just me or does that graph make it look like the average extinction rate has decreased over the history of life? What would cause that?

[Louella]

Is it just me or does that graph make it look like the average extinction rate has decreased over the history of life? What would cause that?

it could be that it's a function of the source data. That specific graph is for marine life. And it's measured by looking at marine fossils. So it can only measure species that exist in forms that leave fossils, which would mostly be things that have skeletons and/or shells.

Maybe at different periods, the conditions in the seas and oceans of the time, weren't favourable to the development of shells/skeletons, so there'd be fewer species that would leave fossils, with subsequent effects on observability of extinctions.

If you look at all the limestone rock formations that exist, then it seems reasonable that the amount of calcium available to marine life has varied greatly over geological time, as the calcium that is bound up in shells and skeletons is deposited and forms limestone, over millions of years, and thus that calcium is unavailable to be dissolved back into the oceans and re-incorporated into other marine life, so shells and skeletons don't appear so much afterwards.

[Moar Boosters]

Is it just me or does that graph make it look like the average extinction rate has decreased over the history of life? What would cause that?

Meteors are always in people's minds as the cause of extinction events, but most of them, including the worst are likely to be geological in origin. As the earth gets older it cools down so it's less likely to do a big fart, or get the squits and kill everything that can't handle the stink.

[cantab]

If life is in some objective sense "advancing" over time, it's not too surprising that species go extinct less easily. That's a very big if though. Mind you the oceans at least have gone the early Cambrian where much life was on the seafloor and much of that was non-moving, to today where much more life swims actively.

[epoca]

Definitely an interesting article.

[magnemoe]

Definitely an interesting article.

I found it over focused on the current crisis, one who is not an huge danger to humanity as a species even with the realistic worst case scenarios.

Yes that would reshape the shape of continents and destroy most cities.

If you go back 25 years nuclear war was the big killer in the drake equation but you never see it nowadays for some reason.

O yes, we are not in a risk of an total nuclear war so no aliens is either. Easy to imagine an alien who is more aggressive and the first response then developing nukes is to use them against all their enemies. This will either result in an worldwide empire or an long drawn out nuclear war, no idea how that would end however an global empire might be a downfall.

Most empires resist change as it disrupt the internal balance, how about the empire use more and more resources and don't bother with developing more advanced methods for extracting. Then they have pumped the easy oil they are out as nobody bothered developing other sources even deep drilling, offshore or injection.

This might hit aliens who change slowly in any case.

Here we have two scenarios who might hit aliens but not us.

Overpopulation is another, they might end up in a mote in the gods eye setting, might hit the other way, if you could easy regulate birthrates early it would be easier to have less kids than start farming.

[epoca]

I find interesting everything that I have never heard of, no matter how "true" or "realistic" it is. I found your comment interesting too

[Pds314]

The thing about the great filter(s) is that they could be in the far past, or the far future, or tomorrow, or yesterday. They could cause a continuous threat that never ends (I.e. alternating periods of could nuclear war forever, with a few decades between each cold war, world duopoly being achievable but world monopoly being impossible, or perhaps major impact events, etc) or they could be one-time threats, like the development of the world's first nuclear weapons or the advent of unintelligent rapidly self-replicating nanotechnology before a countermeasure exists, or whether the world ceases being able to support abiogenesis before the super-heavy impacts end.

Maybe the half-life of advanced civilization is a few hundred years, with it generally reverting to a dark age level of technology before conquering the galaxy. Maybe the inevitable result of civilization is a world governed by a godlike AI who does not permit colonization of the galaxy? Maybe colonizing the galaxy is a lot harder than current models predict, or maybe we've developed amazingly fast and no civilization in our galaxy has yet conquered it. Alternatively, maybe someone has, and we live in a wildlife refuge.

[magnemoe]

The thing about the great filter(s) is that they could be in the far past, or the far future, or tomorrow, or yesterday. They could cause a continuous threat that never ends (I.e. alternating periods of could nuclear war forever, with a few decades between each cold war, world duopoly being achievable but world monopoly being impossible, or perhaps major impact events, etc) or they could be one-time threats, like the development of the world's first nuclear weapons or the advent of unintelligent rapidly self-replicating nanotechnology before a countermeasure exists, or whether the world ceases being able to support abiogenesis before the super-heavy impacts end.

Maybe the half-life of advanced civilization is a few hundred years, with it generally reverting to a dark age level of technology before conquering the galaxy. Maybe the inevitable result of civilization is a world governed by a godlike AI who does not permit colonization of the galaxy? Maybe colonizing the galaxy is a lot harder than current models predict, or maybe we've developed amazingly fast and no civilization in our galaxy has yet conquered it. Alternatively, maybe someone has, and we live in a wildlife refuge.

We don't know the average distance between stars who have planets with life. Might be 20-50 lightyear, this makes it harder than going to the closest star. And this is average, the distance to the next one might be longer. We would hardly send a large mission to a star system with no life, at least not after exploring a few nearby.

Life on the planet might very well be toxic making colonization a non starter. Without life astroid cities or transforming mars is much more interesting.

In short creating lots of interstellar colonies might be very hard, few bother and the ones who do stop after some time.

Remembers humans are explorers, this might be uncommon. Last the ones who creates interstellar empire is likely to do it for the race, the emperor or their fanged god, not people you want to run into.

Other bottlenecks, will not really call them filters. Intelligence happened once on earth, it might be rare, on the other side many mammals and birds are pretty smart, who know that would happens in 20 million years with no humans, still I see it as a long shot.

So you become intelligent, now are you smart enough? Evolution slows a lot then you become an society, you don't have to be an genius to be an hunter gatherer or a farmer. This might bite you later.

Are you able to organize in large groups, and is it enough of you, predators will be limited in numbers, an plant eater would need high protein diet because of the huge brain, this might limit living areas and numbers. Du you have plants and animals you can domesticate? Few of them on many continents on earth.

You are past all this bottlenecks, you even have an alphabet who is nice for printing, this is important to spread knowledge.

Someone invent the steam engine, now you are ready for the industrial revolution, or is you? The steam engine and mass production was important not because it increased production but because it increased production so much the gain could be reinvested into more factories, this generated an snowball effect.

This worked in lazy fare Europe, it would probably not had that effect in imperial China or other central controlled areas. The empire would probably taken the productivity gain for itself. Then you start industrializing you are a race against running out of resources, if you progress is slow you might run out, this might also happen if you are not smart enough.

Finally you got advanced technology, don't start an all out nuclear war, don't create an global empire and clamp down on progress, don't enter the matrix because its more fun. Find the resources for interstellar colonies, and don't stop then its no return for the investment.

[PB666]

So basically everyone knows that non photosynthetic organisms need a source of oxygen. But this is only partially true, many marine organisms and bacteria can survive by scavenging other oxygen species. For example some marine burrowing worms bypass the citric acid cycle in order to avoid depleting precious oxygen. These worms actually feed on the bacteria and bacteriophagic organisms that produce iron sulfide.

In a time of low oxygen diatomic oxygen can be bypassed.

However oceanic anoxia may be more profound. The researchers below found deformations in the skelta of diatoms that appearred shortly after a glacial period. The assumption is that during the period much of the ocean would be covered with ice, and dissolved O2 levels would fall. These authors found a rise associated with these deformed plankton of dissolved heavy metals including lead and arsenic. photosynthetic activity in the ocean is associated with redox potentials in surface waters of around 200 to 500 millivolts. This falls rapidly during anoxia due to the effect of procaryotes on dead organisms and dissolved organi molecules. When redox falls polyvalent metals can reduce for thier +3 or higher oxidation states to alternative lower states. The higher states are associated with the formation of insoluble salts, and lower the oxidation states can make many dissolved metals more soluble in sea water.

http://www.nature.com/ncomms/2015/150825/ncomms8966/full/ncomms8966.html

When we consider the goldilocks zone for planets we should also consider a separate zone nedded for complex life, if the temperature is too cold life up the complexity scale may not evolve past the marine aquatic phase if the conditions in the ancient seas remain anoxic for a variety of reasons in cluding high levels of ice covering and stagnation of currents.

[GeneralVeers]

The article introduces Fermi's paradox, which is basically the "Where is everybody?" question. With the Milky Way alone containing probably billions of planets, how is it possible that no other civilization has yet contacted us?

Run to your bathroom real quick and look in a mirror. You're the reason. Your question can be answered rather elegantly, by simply flipping it around and asking: why haven't HUMANS contacted OTHER CIVILIZATIONS?

There are a couple of things that always bug me when people ask the question you asked:

Number one: the people asking said question always seem to assume the "other civilization" would be more advanced than humans. There's no reason to make that assumption. Exactly one civilization in the universe is the most advanced, and depending on how many other developed civilizations exist, we humans might be it. It's entirely possible somebody else out there is more advanced than us, but we don't know, therefore we shouldn't be making the leap from "possible" to "fact" here.

Number two: the people asking the above question never consider the possibility that we humans ARE that "other" civilization. Right now the inhabitants of Kepler-442B are probably staring up into their own night sky and wondering why nobody else has landed on their planet and said hi. Or tried to blow them up.

So, why haven't humans contacted other civilizations? Answer: we simply haven't found them yet. If some alien race out there is looking for alien life, there's no reason to assume they should have "already" found us. They might. Eventually.

But keep in mind, it's very possible there are no other advanced civilizations out there at all. We humans are kind of a fluke; in the entire history of Earth, a planet with lots of intelligent species, the incident of a critter coming up with the ideas of spoken and written language, tools, stonemasonry, steel, railroads, combustion engines, and spaceflight has only happened once. Even on a planet with intelligent life, the process of a species developing technology and following the same path we did, is extremely rare. There's certainly life elsewhere in the universe; intelligent life, almost certainly. Technologically advanced life? Not likely.