I’m trying to find a way to phrase this question. Perhaps if I say it this way.

Everyone agrees that excessive anthropogenic climate change is bad, and that at least 90%(?) of climate change is anthropogenic. What’s your opinion on the remaining 10% or so?

The natural component of climate change includes El Niño, ice age, younger Dryas, little ice age. So would you choose 1, 2 or 3?

1. The natural component of climate change is good because it’s natural.
2. The natural component of climate change is bad because it puts endangered species at risk.
3. Small amounts of natural climate change (eg. El Niño) are good, but large amounts (eg. ice age) are bad.

If 3, would you count the “little ice age” as good or bad?

Actually, I need to check that 90%, because in excess of 95% of global warming is anthropogenic, but global warming is not synonymous with climate change.

mollwollfumble said:

I’m trying to find a way to phrase this question. Perhaps if I say it this way.

Everyone agrees that excessive anthropogenic climate change is bad, and that at least 90%(?) of climate change is anthropogenic. What’s your opinion on the remaining 10% or so?

The natural component of climate change includes El Niño, ice age, younger Dryas, little ice age. So would you choose 1, 2 or 3?

1. The natural component of climate change is good because it’s natural.
2. The natural component of climate change is bad because it puts endangered species at risk.
3. Small amounts of natural climate change (eg. El Niño) are good, but large amounts (eg. ice age) are bad.

If 3, would you count the “little ice age” as good or bad?

Actually, I need to check that 90%, because in excess of 95% of global warming is anthropogenic, but global warming is not synonymous with climate change.

4. The natural component of climate change is bad (for existing species) because we are not adapted to a warmer climate.

mollwollfumble said:

I’m trying to find a way to phrase this question. Perhaps if I say it this way.

Everyone agrees that excessive anthropogenic climate change is bad, and that at least 90%(?) of climate change is anthropogenic. What’s your opinion on the remaining 10% or so?

The natural component of climate change includes El Niño, ice age, younger Dryas, little ice age. So would you choose 1, 2 or 3?

1. The natural component of climate change is good because it’s natural.
2. The natural component of climate change is bad because it puts endangered species at risk.
3. Small amounts of natural climate change (eg. El Niño) are good, but large amounts (eg. ice age) are bad.

If 3, would you count the “little ice age” as good or bad?

Actually, I need to check that 90%, because in excess of 95% of global warming is anthropogenic, but global warming is not synonymous with climate change.

I wouldn’t call short term recurring events like El Niño “climate change”. I suppose you could say the same about ice ages, but I think a cycle in 10’s of thousands of years is long enough to be considered climate.

As for whether they are good or bad, that depends on whether their overall effect on long term human well-being is good or bad.

Change tends to be bad, because cultures evolve to suit historical conditions, but some changes can be good, and changes may also reduce the negative effects of anthropogenic climate change, which would be good.

The Rev Dodgson said:

mollwollfumble said:

I’m trying to find a way to phrase this question. Perhaps if I say it this way.

Everyone agrees that excessive anthropogenic climate change is bad, and that at least 90%(?) of climate change is anthropogenic. What’s your opinion on the remaining 10% or so?

The natural component of climate change includes El Niño, ice age, younger Dryas, little ice age. So would you choose 1, 2 or 3?

1. The natural component of climate change is good because it’s natural.
2. The natural component of climate change is bad because it puts endangered species at risk.
3. Small amounts of natural climate change (eg. El Niño) are good, but large amounts (eg. ice age) are bad.

If 3, would you count the “little ice age” as good or bad?

Actually, I need to check that 90%, because in excess of 95% of global warming is anthropogenic, but global warming is not synonymous with climate change.

I wouldn’t call short term recurring events like El Niño “climate change”. I suppose you could say the same about ice ages, but I think a cycle in 10’s of thousands of years is long enough to be considered climate.

As for whether they are good or bad, that depends on whether their overall effect on long term human well-being is good or bad.

Change tends to be bad, because cultures evolve to suit historical conditions, but some changes can be good, and changes may also reduce the negative effects of anthropogenic climate change, which would be good.

Yeah things like El Nino and the Indian Ocean Dipole are not climate change but no doubt are influenced by it.
At the moment the IOD is negative so Africa is getting all our rain, big floods there at the moment.

As for whether they are good or bad, that depends on whether their overall effect on long term human well-being is good or bad.

—

Anthropocentrism

Ian said:

As for whether they are good or bad, that depends on whether their overall effect on long term human well-being is good or bad.

—

Anthropocentrism

That’s quite true isn’t it, change is inevitable but humans get quite annoyed by it as it doesn’t suit us but the universe doesn’t care

Cymek said:

Ian said:

As for whether they are good or bad, that depends on whether their overall effect on long term human well-being is good or bad.

—

Anthropocentrism

That’s quite true isn’t it, change is inevitable but humans get quite annoyed by it as it doesn’t suit us but the universe doesn’t care

To my understanding it’s the rate of change which is abnormal.

Cymek said:

Ian said:

As for whether they are good or bad, that depends on whether their overall effect on long term human well-being is good or bad.

—

Anthropocentrism

That’s quite true isn’t it, change is inevitable but humans get quite annoyed by it as it doesn’t suit us but the universe doesn’t care

Of course it is Anthropocentrism.

What other basis is there for declaring changes to be “good” or “bad”?

May as well dump this appalling bit of news in here. Seriously, what were these folks thinking? I guess I know the answer; their wallets.

https://www.sciencealert.com/global-5g-deal-poses-significant-threat-to-weather-forecast-accuracy-experts-warn?perpetual=yes&limitstart=1

Michael V said:

May as well dump this appalling bit of news in here. Seriously, what were these folks thinking? I guess I know the answer; their wallets.

https://www.sciencealert.com/global-5g-deal-poses-significant-threat-to-weather-forecast-accuracy-experts-warn?perpetual=yes&limitstart=1

Wow, how stupid are humans?
I guess a few people would be for lessening the science, if you can’t measure climate as accurately, then we won’t be as certain there is a problem.

>Everyone agrees that excessive anthropogenic climate change is bad, and that at least 90%(?) of climate change is anthropogenic. What’s your opinion on the remaining 10% or so?

it’s not something that can be presented as a percentage

even the loss of structure would be difficult to present as a percentage, for numerous reasons

it’s more about tolerance thresholds, trends, and what your reference is, or baseline or whatever, I don’t know the proper terms

thing that bothers me about seeing it mostly from just temperature, a simple thermostat, is it’s likely not to account for structural loss in the (evolved) system

Per the Milkankovic cycles, the natural component of climate change right now is a gradual cooling, so I suppose you could argue that the effect of the natural component is to partially mitigate against the harmful rapid warming caused by anthropogenic atmospheric changes. In the fair dinkum department, though, the anthropo effects are an order of magnitude greater than the natural rate of change so it’s not going to help us much.

Thanks for feedback. Follow on question.

Given that ‘climate change’ is not synonymous with ‘global warming’, is there a generally accepted definition of climate change?

I can’t think of a good definition. I can think of two bad ones.

• “Climate is the time average of weather and climate change is the time differential of climate”. That definition fails completely because that makes climate change the same as weather.
• “Climate change is the increase in the variation of climate with time”. That definition fails completely because then the definition of climate change fails to include global warming.

mollwollfumble said:

Thanks for feedback. Follow on question.

Given that ‘climate change’ is not synonymous with ‘global warming’, is there a generally accepted definition of climate change?

I can’t think of a good definition. I can think of two bad ones.

• “Climate is the time average of weather and climate change is the time differential of climate”. That definition fails completely because that makes climate change the same as weather.
• “Climate change is the increase in the variation of climate with time”. That definition fails completely because then the definition of climate change fails to include global warming.

The second one is OK. It defines CC but rightly does not try to list causes.

mollwollfumble said:

Thanks for feedback. Follow on question.

Given that ‘climate change’ is not synonymous with ‘global warming’, is there a generally accepted definition of climate change?

I can’t think of a good definition. I can think of two bad ones.

• “Climate is the time average of weather and climate change is the time differential of climate”. That definition fails completely because that makes climate change the same as weather.
• “Climate change is the increase in the variation of climate with time”. That definition fails completely because then the definition of climate change fails to include global warming.

Climate change is change in the climate.
Global warming is increase in the average global temperature over time.

That’s all.

I don’t know why you want to try and make it difficult.

The Rev Dodgson said:

mollwollfumble said:

Thanks for feedback. Follow on question.

Given that ‘climate change’ is not synonymous with ‘global warming’, is there a generally accepted definition of climate change?

I can’t think of a good definition. I can think of two bad ones.

• “Climate is the time average of weather and climate change is the time differential of climate”. That definition fails completely because that makes climate change the same as weather.
• “Climate change is the increase in the variation of climate with time”. That definition fails completely because then the definition of climate change fails to include global warming.

Climate change is change in the climate.
Global warming is increase in the average global temperature over time.

That’s all.

I don’t know why you want to try and make it difficult.

You’re no fun.

The Rev Dodgson said:

mollwollfumble said:

Thanks for feedback. Follow on question.

Given that ‘climate change’ is not synonymous with ‘global warming’, is there a generally accepted definition of climate change?

I can’t think of a good definition. I can think of two bad ones.

• “Climate is the time average of weather and climate change is the time differential of climate”. That definition fails completely because that makes climate change the same as weather.
• “Climate change is the increase in the variation of climate with time”. That definition fails completely because then the definition of climate change fails to include global warming.

Climate change is change in the climate.
Global warming is increase in the average global temperature over time.

That’s all.

I don’t know why you want to try and make it difficult.

So you’re going for wrong definition number 1?

I make it difficult because I want to know how much of climate change is anthropogenic. We know how much global warming is anthropogenic, 95% or more, but we agreed that global warming is not the same as climate change. If we take either definition 1 or definition 2 above, then the amount of climate change due to anthropogenic effects could be very close to zero.

That’s why it’s essential to have a definition of climate change where the anthropogenic component greatly exceeds the natural component.

> The second one is OK. It defines CC but rightly does not try to list causes.

The second one excludes global warming, global warming doesn’t necessarily have any direct effect on the standard deviation of the climate.

In engineering terms, the mean is not equal to the standard deviation.

not sure about the usefulness of the term natural

I mean you could argue everything humans do is natural, on the other end you could argue there is nothing natural left, everything is influenced by humans, of earth and atmosphere. I guess below the surface down at various depths, depending on where you are, you can say it’s probably not effected by man

mollwollfumble said:

The Rev Dodgson said:

mollwollfumble said:

Thanks for feedback. Follow on question.

Given that ‘climate change’ is not synonymous with ‘global warming’, is there a generally accepted definition of climate change?

I can’t think of a good definition. I can think of two bad ones.

• “Climate is the time average of weather and climate change is the time differential of climate”. That definition fails completely because that makes climate change the same as weather.
• “Climate change is the increase in the variation of climate with time”. That definition fails completely because then the definition of climate change fails to include global warming.

Climate change is change in the climate.
Global warming is increase in the average global temperature over time.

That’s all.

I don’t know why you want to try and make it difficult.

So you’re going for wrong definition number 1?

No, how can I be going for a definition that defines climate as weather when I didn’t define climate as weather.

I define climate as what is normally described by the word “climate”.

If you don’t think that “climate” is adequately defined then lets define “climate”.

That way we’ll have climate change covered as well.

Ian said:

As for whether they are good or bad, that depends on whether their overall effect on long term human well-being is good or bad.
—
Anthropocentrism

The Planet Is Fine!

Of course another wrong definition of climate change would be the change in climate you experience by walking 100 km in any direction.

I can’t help wondering if 100 km of climate change is roughly equivalent to 100 years of climate change. Not always of course because 100 km from here could put me under water.

So I’m up to four wrong definitions of climate change and no correct definition. So no way of being able to say X% of climate change is anthropogenic.

I may as well put this here:

https://www.sciencealert.com/the-five-corrupt-pillars-of-climate-change-denial?perpetual=yes&limitstart=1

Michael V said:

I may as well put this here:

https://www.sciencealert.com/the-five-corrupt-pillars-of-climate-change-denial?perpetual=yes&limitstart=1

read that, well writ

Michael V said:

I may as well put this here:

https://www.sciencealert.com/the-five-corrupt-pillars-of-climate-change-denial?perpetual=yes&limitstart=1

Thanks, very interesting. Are they assuming that climate change = global warning? It seems so.

1. Science denial – no complaints there. The science of global warming is undeniable.

2. Climate change is too expensive to fix. Cost benefit? I don’t have any objection to reducing greenhouse gas production. In fact, It’s a good thing.

3. Climate change is good for us, up to a point. That’s undeniably true, because nobody denies that global cooling would be bad.

> The 2010 “Moscow” heatwave killed 11,000 people.
WTF. This is probably just a natural part of climate variability anyway. Looking up original source.https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3984022/
Turns out we’re talking both heat and air pollution from bushfires here. The relevant figure is quoted below. Significant increased deaths from 14 July to 13 August, midsummer. Both heat and air pollution contributed. High air pollution from 3rd to 10th Aug matches the peak in the death rate. The cause of death of 8,750 of those people is heart failure and stroke. An increase in “mental and behavioural disorders” was the third highest killer, not respiratory problems, which I didn’t expect. 83% of excess deaths were for age >65. Their technique looks sound, with two exceptions, they don’t show or even mention the natural variation in climate temperature, and don’t plot death rate for any year prior to 2010, relying instead on a dubious sinusoidal fit to just four years. Four years is nowhere near sufficient to obtain a reliable climate average, 40 years is barely sufficient, 200 years would be better.

> 40 percent of the world’s population also lives in the Tropics
Global warming may not affect the tropics to any significant amount (apart from sea level rise of course), because increased evaporation causes more cloud cover which cancels out the heating effect.

From figure in the article quoted below. See how deaths due to heat have been decreasing, despite a massive increase in population over the past 30 years. That’s encouraging. It’s not necessarily correct, I’m just quoting from the article without checking its accuracy.

4. Political denial. No argument from me here.

5. Crisis denial.

>The final piece of climate change denial is the argument that we should not rush into changing things, especially given the uncertainty raised by the other four areas of denial above.

That’s not “crisis denial”, it has nothing to do with crisis denial. Crisis denial is objecting to the apocalyptic hyperbola of climate change missionaries.

mollwollfumble said:

Of course another wrong definition of climate change would be the change in climate you experience by walking 100 km in any direction.

I can’t help wondering if 100 km of climate change is roughly equivalent to 100 years of climate change. Not always of course because 100 km from here could put me under water.

So I’m up to four wrong definitions of climate change and no correct definition. So no way of being able to say X% of climate change is anthropogenic.

You still haven’t provided any rational objection to the simple definition.

The Rev Dodgson said:

mollwollfumble said:

Of course another wrong definition of climate change would be the change in climate you experience by walking 100 km in any direction.

I can’t help wondering if 100 km of climate change is roughly equivalent to 100 years of climate change. Not always of course because 100 km from here could put me under water.

So I’m up to four wrong definitions of climate change and no correct definition. So no way of being able to say X% of climate change is anthropogenic.

You still haven’t provided any rational objection to the simple definition.

The simple definition, if I remember correctly is “climate change = change of climate” which is nothing but a tautology.

Climate change could be completely disregarded with many the changes required by the human race for the health of the planet and everything living on it.
Pollution for example is bad even if it didn’t warm the planet and we fight wars over access to oil and other resources and allow monopolies to control them.
Whilst most people can’t build solar panels, batteries, etc personally we can buy them and become a lot more energy independent.

mollwollfumble said:

I’m trying to find a way to phrase this question. Perhaps if I say it this way.

Everyone agrees that excessive anthropogenic climate change is bad, and that at least 90%(?) of climate change is anthropogenic. What’s your opinion on the remaining 10% or so?

The natural component of climate change includes El Niño, ice age, younger Dryas, little ice age. So would you choose 1, 2 or 3?

1. The natural component of climate change is good because it’s natural.
2. The natural component of climate change is bad because it puts endangered species at risk.
3. Small amounts of natural climate change (eg. El Niño) are good, but large amounts (eg. ice age) are bad.

If 3, would you count the “little ice age” as good or bad?

Actually, I need to check that 90%, because in excess of 95% of global warming is anthropogenic, but global warming is not synonymous with climate change.

Change is inevitable
for one reason (cause) or another
the climate fluctuates one way or the other
if the changes come too fast for creatures to adapt
they go extinct, what survives evolves to deal with the change.

What many people don’t understand (and won’t accept) is that this time
while we’re not the sole cause of the currant rising temperature our contribution
to it is unquestionably the proverbial straw that is threatening to break the camel’s back.

mollwollfumble said:

I’m trying to find a way to phrase this question. Perhaps if I say it this way.

Everyone agrees that excessive anthropogenic climate change is bad, and that at least 90%(?) of climate change is anthropogenic. What’s your opinion on the remaining 10% or so?

The natural component of climate change includes El Niño, ice age, younger Dryas, little ice age. So would you choose 1, 2 or 3?

1. The natural component of climate change is good because it’s natural.
2. The natural component of climate change is bad because it puts endangered species at risk.
3. Small amounts of natural climate change (eg. El Niño) are good, but large amounts (eg. ice age) are bad.

If 3, would you count the “little ice age” as good or bad?

Actually, I need to check that 90%, because in excess of 95% of global warming is anthropogenic, but global warming is not synonymous with climate change.

Thermohaline circulation

Ogmog said:

mollwollfumble said:

I’m trying to find a way to phrase this question. Perhaps if I say it this way.

Everyone agrees that excessive anthropogenic climate change is bad, and that at least 90%(?) of climate change is anthropogenic. What’s your opinion on the remaining 10% or so?

The natural component of climate change includes El Niño, ice age, younger Dryas, little ice age. So would you choose 1, 2 or 3?

1. The natural component of climate change is good because it’s natural.
2. The natural component of climate change is bad because it puts endangered species at risk.
3. Small amounts of natural climate change (eg. El Niño) are good, but large amounts (eg. ice age) are bad.

If 3, would you count the “little ice age” as good or bad?

Actually, I need to check that 90%, because in excess of 95% of global warming is anthropogenic, but global warming is not synonymous with climate change.

Thermohaline circulation

Maybe: Slow climate change = geological. Rapid climate change = anthropogenic

The Rev Dodgson said:

mollwollfumble said:

Of course another wrong definition of climate change would be the change in climate you experience by walking 100 km in any direction.

I can’t help wondering if 100 km of climate change is roughly equivalent to 100 years of climate change. Not always of course because 100 km from here could put me under water.

So I’m up to four wrong definitions of climate change and no correct definition. So no way of being able to say X% of climate change is anthropogenic.

You still haven’t provided any rational objection to the simple definition.

The simple definition, if I remember correctly is “climate change = change of climate” which is nothing but a tautology.

Perhaps Rev D can better understand if I express it as “Define change in concrete strength”.

Well, there has to be an original state to compare with to get the change. Say, the average of n>10 samples prepared and tested according to AS 1012.14. Then, we have to determine if a new test to AS 1012.24 falls outside the range inferred from the previous samples, and that requires the sample variation for the n previous samples using the appropriate statistical formula. Then we apply say the 95% confidence limit, or perhaps two standard deviations, or perhaps a p value, to say whether there is a change.

So to define climate change (with time) we need three things – a standard (a replacement for AS 1012.24), a baseline length (years), a variance derived from that baseline data, and a confidence limit, sigma value or p value to define whether the change is significant. With corrections of course to eliminate texas sharpshooter and cherry picking effects.

Now, just imagine how much more difficult that would be if we wanted to claim that the variability of concrete strength had changed. You’d need a much longer baseline, more like n>50 samples prepared and tested according to AS 1012.14, and you’d need far more than just one new measurement, at least 10.

When it comes to extreme weather events, like tropical cyclones, far more than 200 years of baseline is needed, or 200 years with some clever combination of interpolation and extrapolation, both of which introduce uncertainty.

Tamb said:

Ogmog said:

mollwollfumble said:

I’m trying to find a way to phrase this question. Perhaps if I say it this way.

Everyone agrees that excessive anthropogenic climate change is bad, and that at least 90%(?) of climate change is anthropogenic. What’s your opinion on the remaining 10% or so?

The natural component of climate change includes El Niño, ice age, younger Dryas, little ice age. So would you choose 1, 2 or 3?

1. The natural component of climate change is good because it’s natural.
2. The natural component of climate change is bad because it puts endangered species at risk.
3. Small amounts of natural climate change (eg. El Niño) are good, but large amounts (eg. ice age) are bad.

If 3, would you count the “little ice age” as good or bad?

Actually, I need to check that 90%, because in excess of 95% of global warming is anthropogenic, but global warming is not synonymous with climate change.

Thermohaline circulation

Maybe: Slow climate change = geological. Rapid climate change = anthropogenic

Makes some sense. With three of four exceptions that immediately spring to mind. Eg. there was no Gulf Stream at the end of the last ice age, and it switching on may have occurred naturally over a rapid time scale.

Ogmog said:

mollwollfumble said:

I’m trying to find a way to phrase this question. Perhaps if I say it this way.

Everyone agrees that excessive anthropogenic climate change is bad, and that at least 90%(?) of climate change is anthropogenic. What’s your opinion on the remaining 10% or so?

The natural component of climate change includes El Niño, ice age, younger Dryas, little ice age. So would you choose 1, 2 or 3?

1. The natural component of climate change is good because it’s natural.
2. The natural component of climate change is bad because it puts endangered species at risk.
3. Small amounts of natural climate change (eg. El Niño) are good, but large amounts (eg. ice age) are bad.

If 3, would you count the “little ice age” as good or bad?

Actually, I need to check that 90%, because in excess of 95% of global warming is anthropogenic, but global warming is not synonymous with climate change.

Change is inevitable
for one reason (cause) or another
the climate fluctuates one way or the other
if the changes come too fast for creatures to adapt
they go extinct, what survives evolves to deal with the change.

What many people don’t understand (and won’t accept) is that this time
while we’re not the sole cause of the currant rising temperature our contribution
to it is unquestionably the proverbial straw that is threatening to break the camel’s back.

A poem. I love it.

mollwollfumble said:

The Rev Dodgson said:

mollwollfumble said:

Of course another wrong definition of climate change would be the change in climate you experience by walking 100 km in any direction.

I can’t help wondering if 100 km of climate change is roughly equivalent to 100 years of climate change. Not always of course because 100 km from here could put me under water.

So I’m up to four wrong definitions of climate change and no correct definition. So no way of being able to say X% of climate change is anthropogenic.

You still haven’t provided any rational objection to the simple definition.

The simple definition, if I remember correctly is “climate change = change of climate” which is nothing but a tautology.

As are the definition of force and the theory of evolution.

Tautologies are useful.

>if the changes come too fast for creatures to adapt
they go extinct, what survives evolves to deal with the change

sort of resembles herbert spencer, vestiges of, poor man’s systems theory, which is quite common these days, you could even catch it watching david attenborough

it wasn’t so much an impoverished view in spencer’s time, as expressed in popular culture, lent to all sorts of vulgar philosophy, justifications for, well, almost anything

anyway, to put you right, i’m waking my third neuron up..

you sort of skipped something important, that (many) creatures maintain a home, could be a burrow or a nest (possibly only for breeding purposes), or it could be a house for a human, and of humans maintaining an environment likely extended to some domesticated animals maybe, and then further on to agriculture. Entire communities became involves, then there was trade between, across lands, and then oceans

at some point the local environment that humans maintain expanded so as to effectively include the entire earth (and its atmosphere)

that the local environment now includes the gas composition of the atmosphere, globally, is only a very recent change

anyway, i’d incline caution when using notions of inevitability, you could sound like a social darwinist

mollwollfumble said:

The Rev Dodgson said:

mollwollfumble said:

Of course another wrong definition of climate change would be the change in climate you experience by walking 100 km in any direction.

I can’t help wondering if 100 km of climate change is roughly equivalent to 100 years of climate change. Not always of course because 100 km from here could put me under water.

So I’m up to four wrong definitions of climate change and no correct definition. So no way of being able to say X% of climate change is anthropogenic.

You still haven’t provided any rational objection to the simple definition.

The simple definition, if I remember correctly is “climate change = change of climate” which is nothing but a tautology.

Perhaps Rev D can better understand if I express it as “Define change in concrete strength”.

Well, there has to be an original state to compare with to get the change. Say, the average of n>10 samples prepared and tested according to AS 1012.14. Then, we have to determine if a new test to AS 1012.24 falls outside the range inferred from the previous samples, and that requires the sample variation for the n previous samples using the appropriate statistical formula. Then we apply say the 95% confidence limit, or perhaps two standard deviations, or perhaps a p value, to say whether there is a change.

So to define climate change (with time) we need three things – a standard (a replacement for AS 1012.24), a baseline length (years), a variance derived from that baseline data, and a confidence limit, sigma value or p value to define whether the change is significant. With corrections of course to eliminate texas sharpshooter and cherry picking effects.

Now, just imagine how much more difficult that would be if we wanted to claim that the variability of concrete strength had changed. You’d need a much longer baseline, more like n>50 samples prepared and tested according to AS 1012.14, and you’d need far more than just one new measurement, at least 10.

When it comes to extreme weather events, like tropical cyclones, far more than 200 years of baseline is needed, or 200 years with some clever combination of interpolation and extrapolation, both of which introduce uncertainty.

Nonetheless, the definition of “change of concrete strength” is the change in the strength of the concrete.

If your point is that there is uncertainty in the rate of climate change and how much is due to anthropogenic effects, of course there is, does anybody dispute that?

The Rev Dodgson said:

mollwollfumble said:

The Rev Dodgson said:

You still haven’t provided any rational objection to the simple definition.

The simple definition, if I remember correctly is “climate change = change of climate” which is nothing but a tautology.

Perhaps Rev D can better understand if I express it as “Define change in concrete strength”.

Well, there has to be an original state to compare with to get the change. Say, the average of n>10 samples prepared and tested according to AS 1012.14. Then, we have to determine if a new test to AS 1012.24 falls outside the range inferred from the previous samples, and that requires the sample variation for the n previous samples using the appropriate statistical formula. Then we apply say the 95% confidence limit, or perhaps two standard deviations, or perhaps a p value, to say whether there is a change.

So to define climate change (with time) we need three things – a standard (a replacement for AS 1012.24), a baseline length (years), a variance derived from that baseline data, and a confidence limit, sigma value or p value to define whether the change is significant. With corrections of course to eliminate texas sharpshooter and cherry picking effects.

Now, just imagine how much more difficult that would be if we wanted to claim that the variability of concrete strength had changed. You’d need a much longer baseline, more like n>50 samples prepared and tested according to AS 1012.14, and you’d need far more than just one new measurement, at least 10.

When it comes to extreme weather events, like tropical cyclones, far more than 200 years of baseline is needed, or 200 years with some clever combination of interpolation and extrapolation, both of which introduce uncertainty.

Nonetheless, the definition of “change of concrete strength” is the change in the strength of the concrete.

If your point is that there is uncertainty in the rate of climate change and how much is due to anthropogenic effects, of course there is, does anybody dispute that?

Only the people who say it’s not happening at all.

i’d be worried about the rapid ice melt, it’s not a good sign

my impression is that the ice is a buffer of sorts

transition said:

i’d be worried about the rapid ice melt, it’s not a good sign

my impression is that the ice is a buffer of sorts

Iceberg B09B has had a big effect also.

Tamb said:

transition said:

i’d be worried about the rapid ice melt, it’s not a good sign

my impression is that the ice is a buffer of sorts

Iceberg B09B has had a big effect also.

We better hope besides them just dropping off into the ocean that they aren’t full of frozen methane

Tamb said:

transition said:

i’d be worried about the rapid ice melt, it’s not a good sign

my impression is that the ice is a buffer of sorts

Iceberg B09B has had a big effect also.

just reading this…
http://australianhumanitiesreview.org/2018/12/02/a-biography-of-iceberg-b09b/

Cymek said:

Tamb said:

transition said:

i’d be worried about the rapid ice melt, it’s not a good sign

my impression is that the ice is a buffer of sorts

Iceberg B09B has had a big effect also.

We better hope besides them just dropping off into the ocean that they aren’t full of frozen methane

This one has disturbed the ecology of Commonwealth Bay & is killing off a penguin colony.

Why do we never get an answer
When we’re knocking at the door
With a thousand million questions
About hate and death and war?
‘Cause when we stop and look around us
There is nothing that we need
In a world of persecution
That is burning in its greed

transition said:

Tamb said:

transition said:

i’d be worried about the rapid ice melt, it’s not a good sign

my impression is that the ice is a buffer of sorts

Iceberg B09B has had a big effect also.

just reading this…
http://australianhumanitiesreview.org/2018/12/02/a-biography-of-iceberg-b09b/

that was very writ, very informative too

transition said:

transition said:

Tamb said:

Iceberg B09B has had a big effect also.

just reading this…
http://australianhumanitiesreview.org/2018/12/02/a-biography-of-iceberg-b09b/

that was very writ, very informative too

very well writ

sarahs mum said:

Why do we never get an answer
When we’re knocking at the door
With a thousand million questions
About hate and death and war?
‘Cause when we stop and look around us
There is nothing that we need
In a world of persecution
That is burning in its greed

It’s a question of balance…

Tamb said:

Ogmog said:

mollwollfumble said:

I’m trying to find a way to phrase this question. Perhaps if I say it this way.

Everyone agrees that excessive anthropogenic climate change is bad, and that at least 90%(?) of climate change is anthropogenic. What’s your opinion on the remaining 10% or so?

The natural component of climate change includes El Niño, ice age, younger Dryas, little ice age. So would you choose 1, 2 or 3?

1. The natural component of climate change is good because it’s natural.
2. The natural component of climate change is bad because it puts endangered species at risk.
3. Small amounts of natural climate change (eg. El Niño) are good, but large amounts (eg. ice age) are bad.

If 3, would you count the “little ice age” as good or bad?

Actually, I need to check that 90%, because in excess of 95% of global warming is anthropogenic, but global warming is not synonymous with climate change.

Thermohaline circulation

Maybe: Slow climate change = geological. Rapid climate change = anthropogenic

My point in bring this forward is to respond to such variations such as “The Mini Ice Age”
While we’re discussing melting ice caps, glaciers & ice bergs, consider the staggering
amount of FRESH WATER —>Suddenly<— being introduced into the system, and how
that effects the overall Sudden Distribution of HEAT Energy WORLD WIDE.

Volcanic activity may have raised the atmospheric Co2 enough to spike the temperature
enough to melt the glaciers holding back the pent up melt water from the last Ice Age,
but the melting glacier was enough to clear the way for billions of tonnes of fresh water
to flow out of the St. Lawrence River to effect the balance of fresh to salt water enough
to slow the Equatorial current responsible for warming Europe making the ‘Mini Ice Age” inevitable. It only took discovering a continent & centuries of science to connect the dots.

Again, my point being
what kind of sudden changes can we expect from melting BOTH Ice Caps + Greenland?

It’s one hellovan experiment …and We’re in the test tube.

Ogmog said:

Tamb said:

Ogmog said:

Thermohaline circulation

Maybe: Slow climate change = geological. Rapid climate change = anthropogenic

My point in bring this forward is to respond to such variations such as “The Mini Ice Age”
While we’re discussing melting ice caps, glaciers & ice bergs, consider the staggering
amount of FRESH WATER —>Suddenly<— being introduced into the system, and how
that effects the overall Sudden Distribution of HEAT Energy WORLD WIDE.

Volcanic activity may have raised the atmospheric Co2 enough to spike the temperature
enough to melt the glaciers holding back the pent up melt water from the last Ice Age,
but the melting glacier was enough to clear the way for billions of tonnes of fresh water
to flow out of the St. Lawrence River to effect the balance of fresh to salt water enough
to slow the Equatorial current responsible for warming Europe making the ‘Mini Ice Age” inevitable. It only took discovering a continent & centuries of science to connect the dots.

Again, my point being
what kind of sudden changes can we expect from melting BOTH Ice Caps + Greenland?

It’s one hellovan experiment …and We’re in the test tube.

> Again, my point being
> what kind of sudden changes can we expect from melting BOTH Ice Caps + Greenland?
> It’s one hellovan experiment …and We’re in the test tube.

It’s an experiment I’d like to try out. But only step by step. Take a small step, stop, take another small step, stop, etc.

By “Sudden” I assume you mean 1 cm per year, you know, ten times as fast as at present. Average thickness 2 km. A sudden melt of BOTH ice caps plus Greenland would ONLY take 200,000 years. I think we can convert to renewable energy by then.

mollwollfumble said:

By “Sudden” I assume you mean 1 cm per year, you know, ten times as fast as at present. Average thickness 2 km. A sudden melt of BOTH ice caps plus Greenland would ONLY take 200,000 years. I think we can convert to renewable energy by then.

The Internet tells me that sea level is rising a about 3 mm/year at the moment.

That would suggest that average ice thickness is decreasing at very much more than 1 mm/year.

The Rev Dodgson said:

mollwollfumble said:

By “Sudden” I assume you mean 1 cm per year, you know, ten times as fast as at present. Average thickness 2 km. A sudden melt of BOTH ice caps plus Greenland would ONLY take 200,000 years. I think we can convert to renewable energy by then.

The Internet tells me that sea level is rising a about 3 mm/year at the moment.

That would suggest that average ice thickness is decreasing at very much more than 1 mm/year.

This: http://www.esa.int/Applications/Observing_the_Earth/CryoSat/Ice_sheet_highs_lows_and_loss
says 500 km3 per year from Antarctica + Greenland.

What is the area?

The Rev Dodgson said:

The Rev Dodgson said:

mollwollfumble said:

By “Sudden” I assume you mean 1 cm per year, you know, ten times as fast as at present. Average thickness 2 km. A sudden melt of BOTH ice caps plus Greenland would ONLY take 200,000 years. I think we can convert to renewable energy by then.

The Internet tells me that sea level is rising a about 3 mm/year at the moment.

That would suggest that average ice thickness is decreasing at very much more than 1 mm/year.

This: http://www.esa.int/Applications/Observing_the_Earth/CryoSat/Ice_sheet_highs_lows_and_loss
says 500 km3 per year from Antarctica + Greenland.

What is the area?

About 16.2 million km2, so that’s about 30 mm /year

The Rev Dodgson said:

The Rev Dodgson said:

The Rev Dodgson said:

The Internet tells me that sea level is rising a about 3 mm/year at the moment.

That would suggest that average ice thickness is decreasing at very much more than 1 mm/year.

This: http://www.esa.int/Applications/Observing_the_Earth/CryoSat/Ice_sheet_highs_lows_and_loss
says 500 km3 per year from Antarctica + Greenland.

What is the area?

About 16.2 million km2, so that’s about 30 mm /year

>>The Greenland ice sheet is 10,000 feet thick in places and contains enough ice to raise sea levels 23 feet (7 meters). In the 20th century, Greenland has lost around 9,000 billion tons of ice in total, accounting for 25 millimeters of sea-level rise. (It takes about 360 billion tons of ice to produce one millimeter of global sea-level rise.)

However, Greenland is dwarfed by the Antarctic ice sheet, which could raise sea level 57 meters if fully melted. Alarmingly, the Antarctic is also undergoing an accelerated melt down, losing six times as much ice as it was four decades ago, a January 14 study reported. Its ice loss averaged 252 billion tons a year over the past decade.

It’s the same story for western North America’s glaciers—ice loss quadrupled since the early 2000s to 12.3 billion tons annually, a recent study revealed.<<

https://www.nationalgeographic.com/environment/2019/01/greeland-ice-melting-four-times-faster-than-thought-raising-sea-level/

PermeateFree said:

The Rev Dodgson said:

The Rev Dodgson said:

This: http://www.esa.int/Applications/Observing_the_Earth/CryoSat/Ice_sheet_highs_lows_and_loss
says 500 km3 per year from Antarctica + Greenland.

What is the area?

About 16.2 million km2, so that’s about 30 mm /year

>>The Greenland ice sheet is 10,000 feet thick in places and contains enough ice to raise sea levels 23 feet (7 meters). In the 20th century, Greenland has lost around 9,000 billion tons of ice in total, accounting for 25 millimeters of sea-level rise. (It takes about 360 billion tons of ice to produce one millimeter of global sea-level rise.)

However, Greenland is dwarfed by the Antarctic ice sheet, which could raise sea level 57 meters if fully melted. Alarmingly, the Antarctic is also undergoing an accelerated melt down, losing six times as much ice as it was four decades ago, a January 14 study reported. Its ice loss averaged 252 billion tons a year over the past decade.

It’s the same story for western North America’s glaciers—ice loss quadrupled since the early 2000s to 12.3 billion tons annually, a recent study revealed.<<

https://www.nationalgeographic.com/environment/2019/01/greeland-ice-melting-four-times-faster-than-thought-raising-sea-level/

The worry also are events we aren’t able to model or predict that could cause some run away effect that isn’t most reversible.

PermeateFree said:

The Rev Dodgson said:

The Rev Dodgson said:

This: http://www.esa.int/Applications/Observing_the_Earth/CryoSat/Ice_sheet_highs_lows_and_loss
says 500 km3 per year from Antarctica + Greenland.

What is the area?

About 16.2 million km2, so that’s about 30 mm /year

>>The Greenland ice sheet is 10,000 feet thick in places and contains enough ice to raise sea levels 23 feet (7 meters). In the 20th century, Greenland has lost around 9,000 billion tons of ice in total, accounting for 25 millimeters of sea-level rise. (It takes about 360 billion tons of ice to produce one millimeter of global sea-level rise.)

However, Greenland is dwarfed by the Antarctic ice sheet, which could raise sea level 57 meters if fully melted. Alarmingly, the Antarctic is also undergoing an accelerated melt down, losing six times as much ice as it was four decades ago, a January 14 study reported. Its ice loss averaged 252 billion tons a year over the past decade.

It’s the same story for western North America’s glaciers—ice loss quadrupled since the early 2000s to 12.3 billion tons annually, a recent study revealed.<<

https://www.nationalgeographic.com/environment/2019/01/greeland-ice-melting-four-times-faster-than-thought-raising-sea-level/

(CNN August 16, 2019) After months of record temperatures, scientists say Greenland’s ice sheet experienced its biggest melt of the summer on Thursday, losing 11 billion tons of surface ice to the ocean — equivalent to 4.4 million Olympic swimming pools.

Greenland’s ice sheet usually melts during the summer, but the melt season typically begins around the end of May; this year it began at the start. It has been melting “persistently” over the past four months, which have recorded all time temperature highs, according to Ruth Mottram, a climate scientist with Danish Meteorological Institute.

This July alone, Greenland’s ice sheet lost 197 billion tons of ice — the equivalent of around 80 million Olympic swimming pools — according to Mottram. She told CNN the expected average would be between 60-70 billion tons at this time of year.

https://edition.cnn.com/2019/08/02/world/greenland-ice-sheet-11-billion-intl/index.html

PermeateFree said:

PermeateFree said:

The Rev Dodgson said:

About 16.2 million km2, so that’s about 30 mm /year

>>The Greenland ice sheet is 10,000 feet thick in places and contains enough ice to raise sea levels 23 feet (7 meters). In the 20th century, Greenland has lost around 9,000 billion tons of ice in total, accounting for 25 millimeters of sea-level rise. (It takes about 360 billion tons of ice to produce one millimeter of global sea-level rise.)

However, Greenland is dwarfed by the Antarctic ice sheet, which could raise sea level 57 meters if fully melted. Alarmingly, the Antarctic is also undergoing an accelerated melt down, losing six times as much ice as it was four decades ago, a January 14 study reported. Its ice loss averaged 252 billion tons a year over the past decade.

It’s the same story for western North America’s glaciers—ice loss quadrupled since the early 2000s to 12.3 billion tons annually, a recent study revealed.<<

https://www.nationalgeographic.com/environment/2019/01/greeland-ice-melting-four-times-faster-than-thought-raising-sea-level/

(CNN August 16, 2019) After months of record temperatures, scientists say Greenland’s ice sheet experienced its biggest melt of the summer on Thursday, losing 11 billion tons of surface ice to the ocean — equivalent to 4.4 million Olympic swimming pools.

Greenland’s ice sheet usually melts during the summer, but the melt season typically begins around the end of May; this year it began at the start. It has been melting “persistently” over the past four months, which have recorded all time temperature highs, according to Ruth Mottram, a climate scientist with Danish Meteorological Institute.

This July alone, Greenland’s ice sheet lost 197 billion tons of ice — the equivalent of around 80 million Olympic swimming pools — according to Mottram. She told CNN the expected average would be between 60-70 billion tons at this time of year.

https://edition.cnn.com/2019/08/02/world/greenland-ice-sheet-11-billion-intl/index.html

It refreezes as the weather gets colder doesn’t it ?

Cymek said:

PermeateFree said:

PermeateFree said:

>>The Greenland ice sheet is 10,000 feet thick in places and contains enough ice to raise sea levels 23 feet (7 meters). In the 20th century, Greenland has lost around 9,000 billion tons of ice in total, accounting for 25 millimeters of sea-level rise. (It takes about 360 billion tons of ice to produce one millimeter of global sea-level rise.)

However, Greenland is dwarfed by the Antarctic ice sheet, which could raise sea level 57 meters if fully melted. Alarmingly, the Antarctic is also undergoing an accelerated melt down, losing six times as much ice as it was four decades ago, a January 14 study reported. Its ice loss averaged 252 billion tons a year over the past decade.

It’s the same story for western North America’s glaciers—ice loss quadrupled since the early 2000s to 12.3 billion tons annually, a recent study revealed.<<

https://www.nationalgeographic.com/environment/2019/01/greeland-ice-melting-four-times-faster-than-thought-raising-sea-level/

(CNN August 16, 2019) After months of record temperatures, scientists say Greenland’s ice sheet experienced its biggest melt of the summer on Thursday, losing 11 billion tons of surface ice to the ocean — equivalent to 4.4 million Olympic swimming pools.

Greenland’s ice sheet usually melts during the summer, but the melt season typically begins around the end of May; this year it began at the start. It has been melting “persistently” over the past four months, which have recorded all time temperature highs, according to Ruth Mottram, a climate scientist with Danish Meteorological Institute.

This July alone, Greenland’s ice sheet lost 197 billion tons of ice — the equivalent of around 80 million Olympic swimming pools — according to Mottram. She told CNN the expected average would be between 60-70 billion tons at this time of year.

https://edition.cnn.com/2019/08/02/world/greenland-ice-sheet-11-billion-intl/index.html

It refreezes as the weather gets colder doesn’t it ?

>>The evidence suggested by a multitude of different measurement techniques suggests that not only is Greenland losing ice but that these ice losses are accelerating at a rapid pace (Velicogna 2009). Further evidence suggests that although ice losses have up to this point primarily occurred in the South and Southwest portions of Greenland, these losses are now spreading to the Northwest sector of the ice sheet (Khan et al 2010).

Although there have been some gains at high altitudes, significant ice losses are occurring at low altitudes (Wouters 2008) along the coastline where glaciers are calving ice into the oceans far quicker than ice is being accumulated at the top of the ice sheet (Rignot and Kanagaratnam 2006).

In conclusion Greenland is losing ice extensively along its margins where fast flowing ice streams are pushing more ice into the ocean than is gained in the center of the ice sheet. For more information on how ice sheets lose mass, a more comprehensive discussion is available here.<<

https://skepticalscience.com/greenland-cooling-gaining-ice.htm

PermeateFree said:

Cymek said:

PermeateFree said:

(CNN August 16, 2019) After months of record temperatures, scientists say Greenland’s ice sheet experienced its biggest melt of the summer on Thursday, losing 11 billion tons of surface ice to the ocean — equivalent to 4.4 million Olympic swimming pools.

Greenland’s ice sheet usually melts during the summer, but the melt season typically begins around the end of May; this year it began at the start. It has been melting “persistently” over the past four months, which have recorded all time temperature highs, according to Ruth Mottram, a climate scientist with Danish Meteorological Institute.

This July alone, Greenland’s ice sheet lost 197 billion tons of ice — the equivalent of around 80 million Olympic swimming pools — according to Mottram. She told CNN the expected average would be between 60-70 billion tons at this time of year.

https://edition.cnn.com/2019/08/02/world/greenland-ice-sheet-11-billion-intl/index.html

It refreezes as the weather gets colder doesn’t it ?

>>The evidence suggested by a multitude of different measurement techniques suggests that not only is Greenland losing ice but that these ice losses are accelerating at a rapid pace (Velicogna 2009). Further evidence suggests that although ice losses have up to this point primarily occurred in the South and Southwest portions of Greenland, these losses are now spreading to the Northwest sector of the ice sheet (Khan et al 2010).

Although there have been some gains at high altitudes, significant ice losses are occurring at low altitudes (Wouters 2008) along the coastline where glaciers are calving ice into the oceans far quicker than ice is being accumulated at the top of the ice sheet (Rignot and Kanagaratnam 2006).

In conclusion Greenland is losing ice extensively along its margins where fast flowing ice streams are pushing more ice into the ocean than is gained in the center of the ice sheet. For more information on how ice sheets lose mass, a more comprehensive discussion is available here.<<

https://skepticalscience.com/greenland-cooling-gaining-ice.htm

Thanks
I was wondering that could it reach a point of no return were no ice refreezes and it all melts in a relatively quick time of a few years and we are ruined.

Cymek said:

PermeateFree said:

Cymek said:

It refreezes as the weather gets colder doesn’t it ?

>>The evidence suggested by a multitude of different measurement techniques suggests that not only is Greenland losing ice but that these ice losses are accelerating at a rapid pace (Velicogna 2009). Further evidence suggests that although ice losses have up to this point primarily occurred in the South and Southwest portions of Greenland, these losses are now spreading to the Northwest sector of the ice sheet (Khan et al 2010).

Although there have been some gains at high altitudes, significant ice losses are occurring at low altitudes (Wouters 2008) along the coastline where glaciers are calving ice into the oceans far quicker than ice is being accumulated at the top of the ice sheet (Rignot and Kanagaratnam 2006).

In conclusion Greenland is losing ice extensively along its margins where fast flowing ice streams are pushing more ice into the ocean than is gained in the center of the ice sheet. For more information on how ice sheets lose mass, a more comprehensive discussion is available here.<<

https://skepticalscience.com/greenland-cooling-gaining-ice.htm

Thanks
I was wondering that could it reach a point of no return were no ice refreezes and it all melts in a relatively quick time of a few years and we are ruined.

There is an awful lot of ice there, so no need to pack your bags just yet.

The Rev Dodgson said:

mollwollfumble said:

By “Sudden” I assume you mean 1 cm per year, you know, ten times as fast as at present. Average thickness 2 km. A sudden melt of BOTH ice caps plus Greenland would ONLY take 200,000 years. I think we can convert to renewable energy by then.

The Internet tells me that sea level is rising a about 3 mm/year at the moment.

That would suggest that average ice thickness is decreasing at very much more than 1 mm/year.

Not in Antarctica.
Most of the sea level rise is from thermal expansion.
But I didn’t check.
So “sudden” catastrophe could be less than 200,000 years.

mollwollfumble said:

The Rev Dodgson said:

mollwollfumble said:

By “Sudden” I assume you mean 1 cm per year, you know, ten times as fast as at present. Average thickness 2 km. A sudden melt of BOTH ice caps plus Greenland would ONLY take 200,000 years. I think we can convert to renewable energy by then.

The Internet tells me that sea level is rising a about 3 mm/year at the moment.

That would suggest that average ice thickness is decreasing at very much more than 1 mm/year.

Not in Antarctica.
Most of the sea level rise is from thermal expansion.
But I didn’t check.
So “sudden” catastrophe could be less than 200,000 years.

The 120 m seal level rise at the end of the last Ice Age took about 8000 years.

How much sea level rise would you consider “catastrophic”?

A good bit less than 120 m I’d suggest.

Bear with me please while I think out loud. Going back right to the start.

Almost all global warming is anthropogenic. But, taking the definition that “climate change” is local as opposed to “global warming” being global, is anthropogenic “climate change” closer to 0% or 100%?

The way I can see to determine that, the only way I can think of, is to compare Global Climate Model predictions with observations. The correlation coefficient between the two is the percentage of climate change that is anthropogenic.

But this leads me to a chicken and egg type of problem. Observed climate change is used to calibrate Global Climate Models. I happen to know that the first generation of Global Climate Models did a very bad job of predicting local changes in climate, so they had to be improved/tweaked until they did.

So any agreement between GCMs and climate change, is it a genuine prediction or is it calibration? How is it possible to tell?

And should there be separate anthropogenic percentages for temperature, rain and wind? And perhaps different again for extreme weather such as hurricanes?

The Rev Dodgson said:

mollwollfumble said:

The Rev Dodgson said:

The Internet tells me that sea level is rising a about 3 mm/year at the moment.

That would suggest that average ice thickness is decreasing at very much more than 1 mm/year.

Not in Antarctica.
Most of the sea level rise is from thermal expansion.
But I didn’t check.
So “sudden” catastrophe could be less than 200,000 years.

The 120 m seal level rise at the end of the last Ice Age took about 8000 years.

How much sea level rise would you consider “catastrophic”?

A good bit less than 120 m I’d suggest.

A lot less than that for Kiribati? Tuvalu? Bangladesh?

mollwollfumble said:

But, taking the definition that “climate change” is local as opposed to “global warming” being global,

Where did that come from?

It makes no sense at all.

Global climate change is global.
Local climate change is local.
Global warming is a component of global climate change.

sarahs mum said:

The Rev Dodgson said:

mollwollfumble said:

Not in Antarctica.
Most of the sea level rise is from thermal expansion.
But I didn’t check.
So “sudden” catastrophe could be less than 200,000 years.

The 120 m seal level rise at the end of the last Ice Age took about 8000 years.

How much sea level rise would you consider “catastrophic”?

A good bit less than 120 m I’d suggest.

A lot less than that for Kiribati? Tuvalu? Bangladesh?

Moll probably considers those to be local catastrophes.

The Rev Dodgson said:

mollwollfumble said:

The Rev Dodgson said:

The Internet tells me that sea level is rising a about 3 mm/year at the moment.

That would suggest that average ice thickness is decreasing at very much more than 1 mm/year.

Not in Antarctica.
Most of the sea level rise is from thermal expansion.
But I didn’t check.
So “sudden” catastrophe could be less than 200,000 years.

The 120 m seal level rise at the end of the last Ice Age took about 8000 years.

How much sea level rise would you consider “catastrophic”?

A good bit less than 120 m I’d suggest.

8,000 years, yes. But consider. The relationship between atmospheric CO2 and global temperatures is very strongly nonlinear. CO2 doesn’t just absorb light at its natural oscillation frequencies, because each absorption line has a bandwidth. It’s the steepness of the edge of that bandwidth that determines the relationship between CO2 concentration and global warming. Got it so far? The higher the CO2 concentration, the steeper the edge of the bandwidth (because we’re further from the centre of the band) and thus the smaller the effect of CO2 concentration on global warming. (Still with me but wondering what this has to do with the price of fish in China?)

What that means is that only a small, a very small change in CO2 concentration, suffices to heat the Earth from freezing cold (ice age) to a warmer temperature. And it follows from that that only a very small increase in CO2 suffices to melt an ice age. But to get further warming (and melting) requires a much greater change in CO2.

In a nutshell, the speed with which the ice age melted could be much faster (because the change in the steepness of the edge of the CO2 absorption bandwidth changes radically with CO2 concentration) than the speed at which Antarctica would melt. Or to put it another way, that 8,000 years to melt the last ice age and the time to melt Antarctica are uncorrelated.

sarahs mum said:

The Rev Dodgson said:

mollwollfumble said:

Not in Antarctica.
Most of the sea level rise is from thermal expansion.
But I didn’t check.
So “sudden” catastrophe could be less than 200,000 years.

The 120 m seal level rise at the end of the last Ice Age took about 8000 years.

How much sea level rise would you consider “catastrophic”?

A good bit less than 120 m I’d suggest.

A lot less than that for Kiribati? Tuvalu? Bangladesh?

Coral grows faster than sea level rises. Reef building coral grows 1 to 8 inches per year.
Flood plains collect silt faster than sea level rises.

So none of the three is in any immediate danger. Even from a 120 metre sea level rise.
Coastal erosion on the other hand, is another matter entirely.

mollwollfumble said:

Flood plains collect silt faster than sea level rises.

So your plan is to elevate existing structures in Dhaka and let the silt build beneath them. It could work.

mollwollfumble said:

The Rev Dodgson said:

mollwollfumble said:

Not in Antarctica.
Most of the sea level rise is from thermal expansion.
But I didn’t check.
So “sudden” catastrophe could be less than 200,000 years.

The 120 m seal level rise at the end of the last Ice Age took about 8000 years.

How much sea level rise would you consider “catastrophic”?

A good bit less than 120 m I’d suggest.

8,000 years, yes. But consider. The relationship between atmospheric CO2 and global temperatures is very strongly nonlinear. CO2 doesn’t just absorb light at its natural oscillation frequencies, because each absorption line has a bandwidth. It’s the steepness of the edge of that bandwidth that determines the relationship between CO2 concentration and global warming. Got it so far? The higher the CO2 concentration, the steeper the edge of the bandwidth (because we’re further from the centre of the band) and thus the smaller the effect of CO2 concentration on global warming. (Still with me but wondering what this has to do with the price of fish in China?)

What that means is that only a small, a very small change in CO2 concentration, suffices to heat the Earth from freezing cold (ice age) to a warmer temperature. And it follows from that that only a very small increase in CO2 suffices to melt an ice age. But to get further warming (and melting) requires a much greater change in CO2.

In a nutshell, the speed with which the ice age melted could be much faster (because the change in the steepness of the edge of the CO2 absorption bandwidth changes radically with CO2 concentration) than the speed at which Antarctica would melt. Or to put it another way, that 8,000 years to melt the last ice age and the time to melt Antarctica are uncorrelated.

What if you are wrong?

mollwollfumble said:

sarahs mum said:

The Rev Dodgson said:

The 120 m seal level rise at the end of the last Ice Age took about 8000 years.

How much sea level rise would you consider “catastrophic”?

A good bit less than 120 m I’d suggest.

A lot less than that for Kiribati? Tuvalu? Bangladesh?

Coral grows faster than sea level rises. Reef building coral grows 1 to 8 inches per year.
Flood plains collect silt faster than sea level rises.

So none of the three is in any immediate danger. Even from a 120 metre sea level rise.
Coastal erosion on the other hand, is another matter entirely.

You know that Bangladesh is not a Pacific Island?

The Rev Dodgson said:

mollwollfumble said:

sarahs mum said:

A lot less than that for Kiribati? Tuvalu? Bangladesh?

Coral grows faster than sea level rises. Reef building coral grows 1 to 8 inches per year.
Flood plains collect silt faster than sea level rises.

So none of the three is in any immediate danger. Even from a 120 metre sea level rise.
Coastal erosion on the other hand, is another matter entirely.

You know that Bangladesh is not a Pacific Island?

Hasn’t it got a lot of tropical resorts?

sibeen said:

The Rev Dodgson said:

mollwollfumble said:

Coral grows faster than sea level rises. Reef building coral grows 1 to 8 inches per year.
Flood plains collect silt faster than sea level rises.

So none of the three is in any immediate danger. Even from a 120 metre sea level rise.
Coastal erosion on the other hand, is another matter entirely.

You know that Bangladesh is not a Pacific Island?

Hasn’t it got a lot of tropical resorts?

https://oceanservice.noaa.gov/education/kits/corals/coral04_reefs.html

Witty Rejoinder said:

mollwollfumble said:

Flood plains collect silt faster than sea level rises.

So your plan is to elevate existing structures in Dhaka and let the silt build beneath them. It could work.

Just looked up a reference for that.
https://sci-hub.tw/https://www.jstor.org/stable/4298887

Bangladesh is currently growing at a rate of 9.7 million tons of “land accretion” per year.

The Rev Dodgson said:

mollwollfumble said:

The Rev Dodgson said:

The 120 m seal level rise at the end of the last Ice Age took about 8000 years.

How much sea level rise would you consider “catastrophic”?

A good bit less than 120 m I’d suggest.

8,000 years, yes. But consider. The relationship between atmospheric CO2 and global temperatures is very strongly nonlinear. CO2 doesn’t just absorb light at its natural oscillation frequencies, because each absorption line has a bandwidth. It’s the steepness of the edge of that bandwidth that determines the relationship between CO2 concentration and global warming. Got it so far? The higher the CO2 concentration, the steeper the edge of the bandwidth (because we’re further from the centre of the band) and thus the smaller the effect of CO2 concentration on global warming. (Still with me but wondering what this has to do with the price of fish in China?)

What that means is that only a small, a very small change in CO2 concentration, suffices to heat the Earth from freezing cold (ice age) to a warmer temperature. And it follows from that that only a very small increase in CO2 suffices to melt an ice age. But to get further warming (and melting) requires a much greater change in CO2.

In a nutshell, the speed with which the ice age melted could be much faster (because the change in the steepness of the edge of the CO2 absorption bandwidth changes radically with CO2 concentration) than the speed at which Antarctica would melt. Or to put it another way, that 8,000 years to melt the last ice age and the time to melt Antarctica are uncorrelated.

What if you are wrong?

If I’m wrong then I may have to move house 2,000 years from now.

JudgeMental said:

sibeen said:

The Rev Dodgson said:

You know that Bangladesh is not a Pacific Island?

Hasn’t it got a lot of tropical resorts?

https://oceanservice.noaa.gov/education/kits/corals/coral04_reefs.html

also flood plains are not really a nice stable platform to build anything, otherwise bangladesh’s ganges delta would be OK.

mollwollfumble said:

Witty Rejoinder said:

mollwollfumble said:

Flood plains collect silt faster than sea level rises.

So your plan is to elevate existing structures in Dhaka and let the silt build beneath them. It could work.

Just looked up a reference for that.
https://sci-hub.tw/https://www.jstor.org/stable/4298887

Bangladesh is currently growing at a rate of 9.7 million tons of “land accretion” per year.

and seeing that this “land” accretion has been happening for all the holocene it is a wonder no one has built much there. Maybe because it is moving all the time.

JudgeMental said:

JudgeMental said:

sibeen said:

Hasn’t it got a lot of tropical resorts?

https://oceanservice.noaa.gov/education/kits/corals/coral04_reefs.html

also flood plains are not really a nice stable platform to build anything, otherwise bangladesh’s ganges delta would be OK.

I suppose there will be an increase in Himalayan runoff until there is a decrease. And who knows what will happen to the monsoon season?

https://www.sciencemag.org/news/2018/03/sea-levels-rise-bangladeshi-islanders-must-decide-between-keeping-water-out-or-letting

JudgeMental said:

mollwollfumble said:

Witty Rejoinder said:

So your plan is to elevate existing structures in Dhaka and let the silt build beneath them. It could work.

Just looked up a reference for that.
https://sci-hub.tw/https://www.jstor.org/stable/4298887

Bangladesh is currently growing at a rate of 9.7 million tons of “land accretion” per year.

and seeing that this “land” accretion has been happening for all the holocene it is a wonder no one has built much there. Maybe because it is moving all the time.

I’m beginning to think that is bloke is closely related to the Observer, if not the Observer. Good God his mind must be like the house contents of a compulsive rubbish hoarder.

JudgeMental said:

JudgeMental said:

sibeen said:

Hasn’t it got a lot of tropical resorts?

https://oceanservice.noaa.gov/education/kits/corals/coral04_reefs.html

also flood plains are not really a nice stable platform to build anything, otherwise bangladesh’s ganges delta would be OK.

Exactly, Jesus was all over this. he often spoke out about building on loose sandy topology.

your future climate could be in the clouds, those fluffy amorphous things magically suspended in the sky

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

transition said:

your future climate could be in the clouds, those fluffy amorphous things magically suspended in the sky

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

this looks like quite a good read but I have book work to do. I’ll leave it open, get back to it later

https://www.windows2universe.org/earth/climate/warming_clouds_albedo_feedback.html

transition said:

your future climate could be in the clouds, those fluffy amorphous things magically suspended in the sky

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

Have rumours of their death been exaggerated?

dv said:

transition said:

your future climate could be in the clouds, those fluffy amorphous things magically suspended in the sky

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

Have rumours of their death been exaggerated?

only on days of no weather

SCIENCE said:

dv said:

transition said:

your future climate could be in the clouds, those fluffy amorphous things magically suspended in the sky

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

Have rumours of their death been exaggerated?

only on days of no weather

Yes, the effect of the increase of cloud cover with increasing ocean surface temperature is the biggest uncertainty in the prediction of global warming.

mollwollfumble said:

SCIENCE said:

dv said:

Have rumours of their death been exaggerated?

only on days of no weather

Yes, the effect of the increase of cloud cover with increasing ocean surface temperature is the biggest uncertainty in the prediction of global warming.

clouds may do the job, but you know if it takes 500 years or 100,000+ years that’s way into the future, potentially a lot of trouble between now and then

some of the climate system may have occurred by way of accidents too, like evolution, so after things change it could be a long wait for a fortuitous accident in the climate system to start to right things

transition said:

mollwollfumble said:

SCIENCE said:

only on days of no weather

Yes, the effect of the increase of cloud cover with increasing ocean surface temperature is the biggest uncertainty in the prediction of global warming.

clouds may do the job, but you know if it takes 500 years or 100,000+ years that’s way into the future, potentially a lot of trouble between now and then

some of the climate system may have occurred by way of accidents too, like evolution, so after things change it could be a long wait for a fortuitous accident in the climate system to start to right things

may have to wait for the next asteroid impact

transition said:

transition said:

mollwollfumble said:

Yes, the effect of the increase of cloud cover with increasing ocean surface temperature is the biggest uncertainty in the prediction of global warming.

clouds may do the job, but you know if it takes 500 years or 100,000+ years that’s way into the future, potentially a lot of trouble between now and then

some of the climate system may have occurred by way of accidents too, like evolution, so after things change it could be a long wait for a fortuitous accident in the climate system to start to right things

may have to wait for the next asteroid impact

Or the next flood basalt. Flood basalts release more CO2 and SO2 than any asteroid, and the next one is due within the next million years or so (as opposed to 100 million years or so for the next big asteroid) – keep a watch on the rift valleys.

Thankfully, although flood basalts on the mid-ocean ridges and deep ocean basins occur far more often than those on land, the massive amounts of CO2 and SO2 that they generate are mostly absorbed in the sea so they haven’t caused any major extinction events. It’s the ones on land that you have to be wary of.

thinking this, I was..

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