Climate Change - General Discussion : Read the Mod Note in post #1 before posting

We were looking at Arctic ice trends weren't we?

Here's an article on Dr. Judith Curry's site by Drs. Connolly which might go some way to calming those who are becoming hysterical about the loss of Arctic ice.

They authors summarise their article here:

"After re-calibrating the pre-satellite data, it now transpires that Arctic sea ice has alternated between periods of sea ice retreat and growth. The satellite record coincidentally began at the end of one of the sea ice growth periods. This has led to people mistakenly thinking the post-1978 sea ice retreat is unusual.

The results from new sea ice proxies taken from ocean sediment cores suggest that Arctic sea ice extent has varied substantially over the last 10,000 years. They also suggest that Arctic sea ice extent was actually less before the Bronze Age than it is today.

The current Global Climate Models are unable to reproduce the observed Arctic sea ice changes since 1901, and they seem to drastically underestimate the natural sea ice variability"

https://judithcurry.com/2017/08/16/what-do-we-know-about-arctic-sea-ice-trends/?utm_content=buffer31718&utm_medium=social&utm_source=twitter.com&utm_campaign=buffer

Their study

http://dx.doi.org/10.1080/02626667.2017.1324974

Here's a nice photo of workers painting roads white in Los Angeles in a frantic bid to cool the place down from the effects of urban heat and to fight climate change.

:pac:

1523372114843.jpg?ve=1&tl=1&text=big-top-image

1523372114843.jpg?ve=1&tl=1&text=big-top-image

I hope it won't confuse the self driving cars.

http://www.foxnews.com/us/2018/04/10/los-angeles-painting-city-streets-white-in-bid-to-combat-climate-change.html

Mr Bumble

Akrasia wrote: »

you've obviously not been reading my posts then. I don't want people to believe my point of view, I want people to believe the science, and I don't want people peddling conspiracy theories instead of the accepting the science behind global warming.

I was pushed to resort to the kind of language as above with Dense because he engages in hit and run arguments using misrepresentation and conflating words and meanings to generate a warped version of events.

I was going to define these terms for him, but I knew he would ignore it, so the only hope I had of getting him to acknowledge the meaning of these terms was to get him to define them himself, or at least think about the definitions privately and realise he's been getting mixed up.

Note the first thing you say in response is another statement of certainty - that I haven't been reading your posts. I have. So you're wrong about that. Fancy that!
That's the problem I have with just about everything you post.
You go on, with great certainty again, to tell me that another poster is "mixed up".
This is a discussion, with differing views. If it's not that, it's a lecture and in this case, with a finger that never stops wagging.

Talking of ice melting, I know we discussed the recent and ongoing discoveries of new man made volcanoes under Antarctica.

The scientists know there's heat from some but they don't know all the details yet.

(And who knows, they might discover another 50 next week the way things are going!)

https://www.sciencenewsforstudents.org/article/giant-volcanoes-lurk-beneath-antarctic-ice

Here's some of what they do know:

Not surprisingly, the maps show a giant blob of superheated rock about 60 miles beneath Mount Sidley, the last of a chain of volcanic mountains in Marie Byrd Land at one end of the transect. More surprisingly, they reveal hot rock beneath the Bentley Subglacial Trench, a deep basin at the other end of the transect.

The Bentley Subglacial Trench is part of the West Antarctic Rift System and hot rock beneath the region indicates that this part of the rift system was active quite recently.

https://source.wustl.edu/2015/12/the-geography-of-antarcticas-underside/

Anyway, we didn't have a graphic representation of all these volcanoes here before now:

Mr Bumble wrote: »

Note the first thing you say in response is another statement of certainty - that I haven't been reading your posts. I have. So you're wrong about that. Fancy that!
That's the problem I have with just about everything you post.
You go on, with great certainty again, to tell me that another poster is "mixed up".
This is a discussion, with differing views. If it's not that, it's a lecture and in this case, with a finger that never stops wagging.

I'm perfectly willing to admit when I'm wrong if someone points out a mistake I have made or refutes a point with a solid argument. I've been wrong plenty of times in the past and will be wrong again in the future, and I might be wrong today. I do acknowledge that my last few posts have been dismissive, and I should definitely avoid that tone, but it was out of frustration rather than any sense of superiority.

I take a lot of time to research my posts on this topic. And when I go to the effort of checking someone's sources and I discover that they say nothing like what it's claimed they say, over and over again, and rather than defend the original point, that poster just makes another wild claim with yet more dodgy sources, its just a pattern of behaviour that I felt needed a different kind of response.

Rather than waste my time checking his sources, I wanted him to have to defend his understanding of what these sources are saying in his own words.

dense wrote: »

Dense, where did you get this image from?
I haven't been able to locate the source

Akrasia wrote: »

I'm perfectly willing to admit when I'm wrong if someone points out a mistake I have made or refutes a point with a solid argument. I've been wrong plenty of times in the past and will be wrong again in the future, and I might be wrong today. I do acknowledge that my last few posts have been dismissive, and I should definitely avoid that tone, but it was out of frustration rather than any sense of superiority.

I take a lot of time to research my posts on this topic. And when I go to the effort of checking someone's sources and I discover that they say nothing like what it's claimed they say, over and over again, and rather than defend the original point, that poster just makes another wild claim with yet more dodgy sources, its just a pattern of behaviour that I felt needed a different kind of response.

Rather than waste my time checking his sources, I wanted him to have to defend his understanding of what these sources are saying in his own words.

Two things, firstly stop referring to me as "he".

I've previously asked you to stop assigning me with your idea of what you think my gender should be, but no, you insist on ignoring my request as if you know best. I find it insulting that you deliberately refer to me as "he".

Secondly, stop making up reasons about "sources" for this bout of your becoming "snarky", your word by the way.

Anyone reading the last few pages of the thread anyone can see you're getting snarky because you've refused to explain what economic and political system the socialist eco activists riding the global warming scam actually want to replace capitalism with.

There's nothing wrong with my sources.

It's just that the heat is now on for you and your eco activist allies in Dail Eireann, Friends of the Earth, An Taisce, People Before Profit, Solidarity etc to come clean and explain things.

Will I throw Brid Smith, Boyd Barret, Copppinger or the Socialist Party an email and let them explain it?

Or do you want to explain it?

Explain why Professor Sweeney (and presumably the other COP20 attendees) were so excited and bowled over after listening to the "star of the show" Bolivian President the socialist Evo Morales impressing everyone talking Climate Change being the result of the "brutal capitalistic system"?

And what you think they'd like to replace it with?

Here's the source, An Taisce:

http://www.antaisce.org/articles/thoughts-lima-2-prof-john-sweeney-reports-cop20-un-climate-conference

And here's the link from an Taisce to the wiki page about the great socialist Evo Morales, the star of Professor Sweeneys show.

https://en.m.wikipedia.org/wiki/Evo_Morales

There's nothing wrong with my sources, it's just that you're not wanting people to see what's really going on in the background.

This "sources" thing of late is just an attempt to distract, a lame excuse to get "snarky".

It's no wonder people feel like they've been driven from the thread.

This is a thread in a science forum about the science of climate change Dense, your 'socialist' nonsense is off topic here. And it is very enlightening that you don't think sources are important.

You (oh sorry, is you not a valid pronoun for 'you') have successfully shown that the socialist party and socialist workers party and the socialists in Bolivia are all socialists. Congratulations. Now you need to show that the UN and the IPCC and the vast majority of the climate scientists and all the scientific bodies of any repute, and all working as puppets for the mighty Bolivia, the SWP and the socialist party.

Wanderer78

dense wrote:

Anyone reading the last few pages of the thread anyone can see you're getting snarky because you've refused to explain what economic and political system the socialist eco activists riding the global warming scam actually want to replace capitalism with.

Please do some research into modern macro economic theory and ultimately it's failures in relation our environmental needs, when these arguments turn into capitalism v's socialism, I dispair, it's like saying the only two colours on the planet is black or white, and we cannot have anything else. Capitalism has benefited mankind greatly but there is something fundamentally wrong with our most predominant form of capitalism, i.e. neoliberalism and our most predominant economic theory, neoclassical theory. You will actually find many of the left leaning individuals and parties you have mentioned actually have a reasonably good understanding of these problems.

Dense will take any criticism of capitalism and spin it into an intention to dismantle capitalism and replace it with the illumaniti

Dense doesn't seem to realise that you can criticise something that you are broadly in support of, or you can criticise one version of something in favour of a different version of the same thing. Capitalism is a broad church, the Swedish are just as capitalist as the Singaporeans despite having very different perspectives on how to deal with market failures.

There are clear market failures when it comes to dealing with environmental pollution. You can be an economics professor in the Chicago school, notoriously pro capitalist insitution, and still accept that government interventions are required in order to make sure the free markets function efficiently.

Akrasia wrote: »

This is a thread in a science forum about the science of climate change Dense, your 'socialist' nonsense is off topic here.

Then why bring the Syrian war into it?

The World Bank?

There are 3 broad areas for discussion relating to climate change and these are broken down by the IPCC into the 3 working groups, Firstly the physical science, working group 1, is it happening, and secondly, WG2, Impacts, Adaptation, and Vulnerability, what will it's effects be.
WG3 is the section relating to mitigation. what changes do we need to make to prevent the as many negative effects as we can

Syria/future conflicts related to heatwaves, drought, famine, internal displacement are all relevant to working group 2, they are all impacts of global warming that can be studied scientifically and discussed based on the evidence collected by researchers and international agencies.

There is a huge difference between discussing the consequences of global warming and referring to studies that show projected effects on population migration and conflict, and saying that global warming is all made up to push for a global socialist one world government.

Akrasia wrote: »

There are 3 broad areas for discussion relating to climate change and these are broken down by the IPCC into the 3 working groups, Firstly the physical science, working group 1, is it happening, and secondly, WG2, Impacts, Adaptation, and Vulnerability, what will it's effects be.

You are not at an UNIPCC love in.

This is a discussion on a board in a country which is being threatened with millions of euros of fines for "climate change" that no one is able attribute to it, a country where socialist politicians who want to have their cake and eat it are virtue signalling about their success ending fossil fuel exploration, where stupid activists celebrate the fact that they are bringing the government to court for failing to avert climate change and where a Citizens Assembly of apparent climate justice enthusiasts vote for higher taxes whilst being unable to articulate how it will avert climate change.

If you would concede the absolute stupidity of those actions instead of defending them, people might be interested in your crusade to get the UNIPCC's agenda driven political scientists and the Bolivian President's Number One Fan, Professor Sweeney, taken seriously.

Getting back to the science and away from the nonsense above

2 new studies released this week in Nature both show that the AMOC (gulf stream) has decreased by 15% since the middle of the 20th Century and is now likely to be at it's weakest strength in at least 1k years (at least 1.6k years according to one of the studies)

The studies both took different methodologies and while there are some areas of disagreement, the authors of both studies conclude that this is yet another fingerprint of climate change

The high resolution climate models predict a very similar pattern of change to what we have been witnessing.

Here we provide several lines of palaeo-oceanographic evidence that Labrador Sea deep convection and the AMOC have been anomalously weak over the past 150 years or so (since the end of the Little Ice Age, LIA, approximately AD 1850) compared with the preceding 1,500 years. Our palaeoclimate reconstructions indicate that the transition occurred either as a predominantly abrupt shift towards the end of the LIA, or as a more gradual, continued decline over the past 150 years
https://www.nature.com/articles/s41586-018-0007-4

Here we provide evidence for a weakening of the AMOC by about 3 ± 1 sverdrups (around 15 per cent) since the mid-twentieth century. This weakening is revealed by a characteristic spatial and seasonal sea-surface temperature ‘fingerprint’—consisting of a pattern of cooling in the subpolar Atlantic Ocean and warming in the Gulf Stream region—and is calibrated through an ensemble of model simulations from the CMIP5 project. We find this fingerprint both in a high-resolution climate model in response to increasing atmospheric carbon dioxide concentrations, and in the temperature trends observed since the late nineteenth century.
https://www.nature.com/articles/s41586-018-0006-5

Akrasia wrote: »

Getting back to the science and away from the nonsense above

2 new studies released this week in Nature both show that the AMOC (gulf stream) has decreased by 15% since the middle of the 20th Century and is now likely to be at it's weakest strength in at least 1k years (at least 1.6k years according to one of the studies)

The studies both took different methodologies and while there are some areas of disagreement, the authors of both studies conclude that this is yet another fingerprint of climate change

The high resolution climate models predict a very similar pattern of change to what we have been witnessing.

So the weakening started 150 years ago. It can't be due to aghg so.

Gaoth Laidir wrote: »

So the weakening started 150 years ago. It can't be due to aghg so.

And, from the article that the above post was scraped from:

For now, the timing of the AMOC decline remains a source of intrigue.

Source:
https://www.nature.com/articles/d41586-018-04086-4

Gaoth Laidir wrote: »

So the weakening started 150 years ago. It can't be due to aghg so.

It doesn't mean it can't be aghg, it means that there might be another underlying natural mechanism. We can't know where the AMOC strength would be today if it wasn't for the warming caused by human influence.

These studies both show that the AMOC is down at least 15% and is the lowest in over a thousand years. It fits with the AGW hypothesis. If there is another mechanism that better explains this, it needs to a robust theory accompanied with supporting evidence.

https://www.nasa.gov/topics/earth/features/atlantic20100325.html

Akrasia wrote: »

It doesn't mean it can't be aghg, it means that there might be another underlying natural mechanism. We can't know where the AMOC strength would be today if it wasn't for the warming caused by human influence.

These studies both show that the AMOC is down at least 15% and is the lowest in over a thousand years. It fits with the AGW hypothesis. If there is another mechanism that better explains this, it needs to a robust theory accompanied with supporting evidence.

According to NASA it fluctuates naturally, +/- 15% so I wouldn't panic about it.

With this new technique, Willis was able to calculate changes in the northward-flowing part of the circulation at about 41 degrees latitude, roughly between New York and northern Portugal. Combining satellite and float measurements, he found no change in the strength of the circulation overturning from 2002 to 2009.

Looking further back with satellite altimeter data alone before the float data were available, Willis found evidence that the circulation had sped up about 20 percent from 1993 to 2009. This is the longest direct record of variability in the Atlantic overturning to date and the only one at high latitudes.

The latest climate models predict the overturning circulation will slow down as greenhouse gases warm the planet and melting ice adds freshwater to the ocean. "Warm, freshwater is lighter and sinks less readily than cold, salty water," Willis explained.

For now, however, there are no signs of a slowdown in the circulation.
"The changes we're seeing in overturning strength are probably part of a natural cycle," said Willis.

"The slight increase in overturning since 1993 coincides with a decades-long natural pattern of Atlantic heating and cooling."

If or when the overturning circulation slows, the results are unlikely to be dramatic.

Akrasia wrote: »

It doesn't mean it can't be aghg, it means that there might be another underlying natural mechanism. We can't know where the AMOC strength would be today if it wasn't for the warming caused by human influence.

These studies both show that the AMOC is down at least 15% and is the lowest in over a thousand years. It fits with the AGW hypothesis. If there is another mechanism that better explains this, it needs to a robust theory accompanied with supporting evidence.

You can't have it both ways. The decline started decades before the start of the rise in temperature trend around 1890 (and that rise was not aghc-related). So yes, something big was already happening for nearly a century before the recent warming post 1970, and it was indeed natural. It started when CO2 was still well below 300 ppm.

Gaoth Laidir wrote: »

You can't have it both ways. The decline started decades before the start of the rise in temperature trend around 1890 (and that rise was not aghc-related). So yes, something big was already happening for nearly a century before the recent warming post 1970, and it was indeed natural. It started when CO2 was still well below 300 ppm.

I'm not trying to have it both ways. I'm trying to look at it rationally.

What is this 'something big' that started to happen around 1890?

The study says there is decadal scale variability in the thousand years before this decline started. The study says that it's never been as weak as it is now in the 1600 years they looked at. This study also lacks the resolution to say if it was a sudden decline 150 years ago or a slow steady decline for the past century because there is uncertainty in their data due to non AMOC influences in their data. Further study is required to reduce these uncertainty bars

The other study in the same edition of Nature is more confident that the change has been mostly in the 2nd half of the 20th century, so we have two studies using different methods and looking at different measuremant data. They both see a 15%+ drop in AMOC strength, one study is unsure of the timing, and the other directly measured the timing to be late 20th century warming.

Regardless of whether this is a natural or anthroprogenic change, a declining AMOC is something we should be carefully monitoring as it has implications for our climate, and if it's not caused by AGW, and there is some mystery cause, we should be trying to explain what this is.

Here's a really cool animation created using a sh1t load of super computing power and a circulation model run over 6 months that shows the complex interaction in ocean currents between hot water from the topics and cold water from the arctic and glaciers.
https://vimeo.com/27076776

It looks to me like the AMOC may have been naturally declining as a we are in a natural interglacial period, but may have been accelerated by human influences.

There is a good discussion on it at Realclimate here in an article written by a climate scientist who helped write one of those Nature studies. It discusses not just these two latest studies, but the recent literature on the subject

http://www.realclimate.org/index.php/archives/2018/04/stronger-evidence-for-a-weaker-atlantic-overturning-circulation/

Here are the researchers themselves discussing their research

Akrasia wrote: »

Here are the researchers themselves discussing their research

And in that he says that the sst pattern change emerged around 1870, i.e. it preceded the warming by about 20 years. What happened in the last 50 years is up for debate, as is its significance, given the lack of historical context. Just don't attribute a slow down in the AMOC to aghc.

Gaoth Laidir wrote: »

And in that he says that the sst pattern change emerged around 1870, i.e. it preceded the warming by about 20 years. What happened in the last 50 years is up for debate, as is its significance, given the lack of historical context. Just don't attribute a slow down in the AMOC to aghc.

You say the last 50 years is up for debate but definitely not agw?

Akrasia wrote: »

You say the last 50 years is up for debate but definitely not agw?

No, I'm not saying that. I'm saying that if something starts to happen a century before agw really kicks in then it can't be attributed to agw. Whether or not agw subsequently prolonged it/made it worse/better in the last 50 years is only secondary. But the quote "agw has caused the AMOC to slow down" is a little misleading as it implies it was the cause of the start of it.

It's the same with the start of the pre-1900 warming. Not anthropogenic in nature but still widely quoted as being the start of the human fingerprint.

M.T. Cranium

Meanwhile, three warm days since the middle of November ...

Gaoth Laidir wrote: »

No, I'm not saying that. I'm saying that if something starts to happen a century before agw really kicks in then it can't be attributed to agw. Whether or not agw subsequently prolonged it/made it worse/better in the last 50 years is only secondary. But the quote "agw has caused the AMOC to slow down" is a little misleading as it implies it was the cause of the start of it.

It's the same with the start of the pre-1900 warming. Not anthropogenic in nature but still widely quoted as being the start of the human fingerprint.

OK, you're interpreting it as 'the cause' rather than 'a cause'

Fair enough. We still need to find out what caused the initial slowdown of the AMOC prior to the bulk of human emissions of ghgs in order to assertain whether that cause is still in effect now, or if it was a natural event that is no longer forcing a weakening of the AMOC, and to find out what proportion of the weakening is natural or human influenced.

M.T. Cranium wrote: »

Meanwhile, three warm days since the middle of November ...

That's true. For Ireland.
Globally February was 5th or 6th warmest February on record according to NASA and NOAA

Akrasia wrote: »

Globally February was 5th or 6th warmest February on record according to NASA and NOAA

It was the 11th warmest February since 1880 according to NOAA.