Climate Change - The Scientific Debate (Vol. II)

[Kawasicki]

ludo said:

DibblyDobbler said:

Fair enough - I was seeking to broaden things out

I'm comfortable that the planet appears to be slowly warming but is it 100% caused by us... 0%... somewhere in between? That, for me at least, is the main issue.

It isn't slowly warming. Can you give examples of when it has warmed by a similar amount (or more) at a faster rate?

We don’t know if the current rate of warming in unusual. We don’t have data with high enough resolution. The fact that we don’t know, yet make alarming statements is pure climate science, also known as pure BS.

[ludo]

Kawasicki said:

ludo said:

DibblyDobbler said:

Fair enough - I was seeking to broaden things out

I'm comfortable that the planet appears to be slowly warming but is it 100% caused by us... 0%... somewhere in between? That, for me at least, is the main issue.

It isn't slowly warming. Can you give examples of when it has warmed by a similar amount (or more) at a faster rate?

We don’t know if the current rate of warming in unusual. We don’t have data with high enough resolution. The fact that we don’t know, yet make alarming statements is pure climate science, also known as pure BS.

If we don't have data with high enough resolution, we can't say it is warming slowly either. In science you have to be prepared to defend your claims with evidence.

I haven't made any alarming statements, so that is your straw-man.

[Kawasicki]

ludo said:

Kawasicki said:

ludo said:

DibblyDobbler said:

Fair enough - I was seeking to broaden things out

I'm comfortable that the planet appears to be slowly warming but is it 100% caused by us... 0%... somewhere in between? That, for me at least, is the main issue.

It isn't slowly warming. Can you give examples of when it has warmed by a similar amount (or more) at a faster rate?

We don’t know if the current rate of warming in unusual. We don’t have data with high enough resolution. The fact that we don’t know, yet make alarming statements is pure climate science, also known as pure BS.

If we don't have data with high enough resolution, we can't say it is warming slowly either. In science you have to be prepared to defend your claims with evidence.

I haven't made any alarming statements, so that is your straw-man.

Do we have data with high enough resolution to support the conclusion that it is currently warming at an unusual rate?

[ludo]

Kawasicki said:

Do we have data with high enough resolution to support the conclusion that it is currently warming at an unusual rate?

I'd say so, the proxy records show that it is warming faster than at any time in the last 2000 years. The Vostok ice core has high resolution for the last 10,000 years and it hasn't warmed as fast in that time either (at least in that region), I gather the Marcott et al proxy reconstruction suggests likewise.

[Kawasicki]

ludo said:

Kawasicki said:

Do we have data with high enough resolution to support the conclusion that it is currently warming at an unusual rate?

I'd say so, the proxy records show that it is warming faster than at any time in the last 2000 years. The Vostok ice core has high resolution for the last 10,000 years and it hasn't warmed as fast in that time either (at least in that region), I gather the Marcott et al proxy reconstruction suggests likewise.

This isn’t a science thread.

Do you really believe proxy temperature records can reliably resolve down to 0.1 degrees per decade?

Statisticians don’t.

https://cpb-us-e1.wpmucdn.com/sites.northwestern.e...

[Halb]

ludo said:

I'd say so, the proxy records show that it is warming faster than at any time in the last 2000 years. The Vostok ice core has high resolution for the last 10,000 years and it hasn't warmed as fast in that time either (at least in that region), I gather the Marcott et al proxy reconstruction suggests likewise.

The period before the Younger Dryas had rapid warming, and cooling.

[ludo]

Kawasicki said:

This isn’t a science thread.

The title of the thread is "Climate Change - The Scientific Debate - Vol II"

Kawasicki said:

Do you really believe proxy temperature records can reliably resolve down to 0.1 degrees per decade?

That is according to two statisticians, apparently with no previous expertise in climate. Their paper was followed by thirteen discussion papers by other statisticians and scientists who do have expertise in the subject (e.g. Schmidt et al.), who suggest otherwise.

Your assertion that

Kawasicki said:

Statisticians don’t.

https://cpb-us-e1.wpmucdn.com/sites.northwestern.e...

is, shall we say "overstating" things somewhat!

It's not difficult to find individual papers that tell a story you want to here, but science (and genuine skepticism) requires that to be put in the proper context.

[ludo]

Halb said:

ludo said:

I'd say so, the proxy records show that it is warming faster than at any time in the last 2000 years. The Vostok ice core has high resolution for the last 10,000 years and it hasn't warmed as fast in that time either (at least in that region), I gather the Marcott et al proxy reconstruction suggests likewise.

The period before the Younger Dryas had rapid warming, and cooling.

Yes, it did. It was a very long time ago. If you have to go back almost to the end of the last ice age to find a similarly fast change, then I would say the current rate of warming is unusual and certainly isn't "slow"

Halb said:

ludo said:

You would be better off reading a book (e.g. Spencer Weart's "The Discovery of climate change", which is also available online https://history.aip.org/climate/index.htm is a good starting point). This thread contains much that is, err, "unreliable".

I feel lost with with the whole thing.
This book, has lots of data?

Fast learner! ;o)

[ludo]

I should add I am not overly critical of McShane and Wyner, and neither were the research community. It apparently had some good ideas in it, but problems with the execution, which were exposed in the commentaries. The point is that it hasn't stood the test of time as a criticism of the proxy records, but was a useful contribution to research on the topic.

[kerplunk]

ludo said:

Halb said:

ludo said:

I'd say so, the proxy records show that it is warming faster than at any time in the last 2000 years. The Vostok ice core has high resolution for the last 10,000 years and it hasn't warmed as fast in that time either (at least in that region), I gather the Marcott et al proxy reconstruction suggests likewise.

The period before the Younger Dryas had rapid warming, and cooling.

Yes, it did. It was a very long time ago. If you have to go back almost to the end of the last ice age to find a similarly fast change, then I would say the current rate of warming is unusual and certainly isn't "slow"

And invoking the last time the climate underwent a radical transition to a different state isn't exactly reassuring.

[Halb]

ludo said:

Halb said:

ludo said:

I'd say so, the proxy records show that it is warming faster than at any time in the last 2000 years. The Vostok ice core has high resolution for the last 10,000 years and it hasn't warmed as fast in that time either (at least in that region), I gather the Marcott et al proxy reconstruction suggests likewise.

The period before the Younger Dryas had rapid warming, and cooling.

Yes, it did. It was a very long time ago. If you have to go back almost to the end of the last ice age to find a similarly fast change, then I would say the current rate of warming is unusual and certainly isn't "slow"

Halb said:

ludo said:

You would be better off reading a book (e.g. Spencer Weart's "The Discovery of climate change", which is also available online https://history.aip.org/climate/index.htm is a good starting point). This thread contains much that is, err, "unreliable".

I feel lost with with the whole thing.
This book, has lots of data?

Fast learner! ;o)

I occasionally pop into this thread, but soon loose interest.
However, the younger dryas period is a crossover from my interest on comet impacts, ancient antediluvian civilisations. I made a thread in the science forum about it. Graham Hancock wrote a book a few years ago about it. So I've red about the younger dryas and it's associated rapid changes either side. Coming from the point of view of 'how old are human civilisations...Gobekli Tepe etc which disrupts accepted history wholly). So as to the science, no, still a n00b, but to history and other things, I've read a book. I would disagree that going that far back is not 'recent.' It's very recent, just not recent in human terms. As to what created that period of rapid change, I think the comet theory is highly interesting.

[Halb]

https://www.pistonheads.com/gassing/topic.asp?t=15...

[hairykrishna]

ludo said:

h
Nice to see this place hasn't changed much though. The same old canards... ;o)

Welcome back. It's much the same as it always was.

[ludo]

hairykrishna said:

ludo said:

h
Nice to see this place hasn't changed much though. The same old canards... ;o)

Welcome back. It's much the same as it always was.

Yes, I'd noticed ;o)

First promoting the 70 concerns about HADCRUT4 "book" (which can actually be downloaded for free, it is just the authors PhD thesis AFAICS), without mentioning the caveat it contains

McLean said:

The audit covers a broad range of issues but leaves the quantifying of the impact of such errors to others,

Yes, that's right, he never even bothered to find out if any of his "concerns" actually made a non-negligible difference to the dataset. The fact that the BEST group went one step further and found out whether the corrections for UHI effect and other biases/issues actually made a difference (and in doing so validated HADCRUT and GISSTEMP etc.) wasn't mentioned either.

Then we have McShane and Wyner raised as implying that "statisticians" didn't think the proxy records had sufficient resolution, ...

Kawasicki said:

Do you really believe proxy temperature records can reliably resolve down to 0.1 degrees per decade?

Statisticians don’t.

https://cpb-us-e1.wpmucdn.com/sites.northwestern.e...

but ignored the 13 comments papers published with it, showing that might be the view of those two particular statisticians, but it certainly isn't true more generally.

It's almost as if "skeptics" stop looking as soon as the find some paper that says what they want it to say, and don't actually care whether it is actually correct or not! ;o)

plus ca change...

[Kawasicki]

ludo said:

Kawasicki said:

Do you really believe proxy temperature records can reliably resolve down to 0.1 degrees per decade?

Statisticians don’t.

https://cpb-us-e1.wpmucdn.com/sites.northwestern.e...

but ignored the 13 comments papers published with it, showing that might be the view of those two particular statisticians, but it certainly isn't true more generally.

It's almost as if "skeptics" stop looking as soon as the find some paper that says what they want it to say, and don't actually care whether it is actually correct or not! ;o)

plus ca change...

I didn’t ignore the 13 comments papers. I read 4 or 5 of them.

Why do you think I ignored them?

It’s almost as if believers get an idea in their head, without any evidence to support it.

[ludo]

Kawasicki said:

I didn’t ignore the 13 comments papers. I read 4 or 5 of them.

Why do you think I ignored them?

The fact that you portrayed the paper as implying statisticians didn't think the proxy records were reliable and didn't mention that there were plenty of statisticians there that poked serious holes in McShane and Wyner's paper.

If you actually knew about the 13 comments papers and didn't mention them, frankly that is far worse than not having looked. Not looking is intellectually lazy; not mentioning them is intellectually dishonest. IMHO.

[Jinx]

ludo said:

Anybody willing to agree that climate skeptic scientists (Berkeley Earth) independently reproducing the results obtained by HADCRUT, using their own independently developed method, is evidence that HadCRUT is not biased or substantially flawed?

Richard Muller was never a skeptic.

And if you want an equivalent warming trend comparable with the recent one we only have to go back to 1930-1950.

[ludo]

Jinx said:

Richard Muller was never a skeptic.

While he wasn't skeptical of the basic physics of the greenhouse effect (he is after all a physicist), he was openly skeptical of the proxy reconstructions and of the instrumental datasets such as HADCRUT that indicate there was a serious issue that society needs to address.

Muller said:

CALL me a converted skeptic. Three years ago I identified problems in previous climate studies that, in my mind, threw doubt on the very existence of global warming. Last year, following an intensive research effort involving a dozen scientists, I concluded that global warming was real and that the prior estimates of the rate of warming were correct. I’m now going a step further: Humans are almost entirely the cause.

( source)

Jinx said:

And if you want an equivalent warming trend comparable with the recent one we only have to go back to 1930-1950.

The question is of post-industrial temperature increases. We didn't start emitting CO2 on a large scale in 1950 (there is also the matter of land-use change emissions as well as fossil fuel emissions).

You didn't answer the question, do you accept that the BEST project essentially validates HADCRUT?

Muller said:

When we began our study, we felt that skeptics had raised legitimate issues, and we didn't know what we'd find. Our results turned out to be close to those published by prior groups. We think that means that those groups had truly been very careful in their work, despite their inability to convince some skeptics of that. They managed to avoid bias in their data selection, homogenization and other corrections.

( source)

[Jinx]

ludo said:

Jinx said:

Richard Muller was never a skeptic.

While he wasn't skeptical of the basic physics of the greenhouse effect (he is after all a physicist), he was openly skeptical of the proxy reconstructions and of the instrumental datasets such as HADCRUT that indicate there was a serious issue that society needs to address.

Muller said:

CALL me a converted skeptic. Three years ago I identified problems in previous climate studies that, in my mind, threw doubt on the very existence of global warming. Last year, following an intensive research effort involving a dozen scientists, I concluded that global warming was real and that the prior estimates of the rate of warming were correct. I’m now going a step further: Humans are almost entirely the cause.

( source)

Jinx said:

And if you want an equivalent warming trend comparable with the recent one we only have to go back to 1930-1950.

The question is of post-industrial temperature increases. We didn't start emitting CO2 on a large scale in 1950 (there is also the matter of land-use change emissions as well as fossil fuel emissions).

You didn't answer the question, do you accept that the BEST project essentially validates HADCRUT?

Muller said:

When we began our study, we felt that skeptics had raised legitimate issues, and we didn't know what we'd find. Our results turned out to be close to those published by prior groups. We think that means that those groups had truly been very careful in their work, despite their inability to convince some skeptics of that. They managed to avoid bias in their data selection, homogenization and other corrections.

( source)

There are more than enough quotes to show Muller was never a skeptic. All the above can be seen through a marketing perspective for their product being better than those that have gone before (but not contradicting them as there's no money in that).

None of the data we have prior to last century from proxies is granular enough to determine the rates of changes we measure from thermometers - if we reduce the resolution of the current data we have (so we effectively have 2 maybe three points of data) and adjust for location we find not too much to worry about in epoch terms.

The data we have is poor and was not collected for the purpose it is being used for. Only the recent data we have is of a good enough standard and unfortunately spatially it is sparse and temporally short.

[ludo]

Jinx said:

There are more than enough quotes to show Muller was never a skeptic.

well quote some of them then. Common sense should tell you that it would be a waste of Muller's time and energy to set up Berkeley Earth if he genuinely thought the instrumental records were fine.

jinx said:

All the above can be seen through a marketing perspective for their product being better than those that have gone before (but not contradicting them as there's no money in that).

But it isn't though, is it? There isn't a great deal to choose between the various existing datasets. They all have their strengths and weaknesses, but none of them dominates the others.

Jinx said:

None of the data we have prior to last century from proxies is granular enough to determine the rates of changes we measure from thermometers - if we reduce the resolution of the current data we have (so we effectively have 2 maybe three points of data) and adjust for location we find not too much to worry about in epoch terms.

The data we have is poor and was not collected for the purpose it is being used for. Only the recent data we have is of a good enough standard and unfortunately spatially it is sparse and temporally short.

I notice that you have evaded the question yet again.