Schrodinger's cat

Dammit, I hate this word processor!

"Where is the heat coming from that has warmed us for 300 years after the LIA but before AGW?

Could you clarify?

Golf Charlie will confirm that the LIA is generally accepted as starting with the eruption of Mount Salamas in 1257 and ended when temperatures stabilised in the 1850s.

EM, I think I haven't got the point across re thunderstorms. At noon, it's a sunny day. Photons are whizzing about, upwelling and down-welling IR seeking equilibrium. By three a massive thunderstorm comes in, transporting heat upwards via convection, heat extracted from the sea at the expense of latent heat. To me, that is a lot of heat bypassing the photon/IR mechanism. once it gets up there it will radiate away. By 5pm the sun is out again, albeit lower in the sky, and we revert to clear skies. There are tens of thousands of these storms all over- well, anywhere warm. You cannot in honesty skip modelling at a resolution which cannot account for them but handles them by parameterisation.

Neither can you build a GCM without getting the ocean right, if you plan to make long-term predictions. El Nino is not just a hiccup.

'" is generally accepted as starting with the eruption of Mount Salamas in 1257"

'Suggested by some' would be more accurate. And that would require a persistence of effect which hasn't been seen in any other holocene eruptions. It's a stretch.

Mt. Salamas (island of Lombok in Indonesia) was only identified as the source of sulphate in Greenland ice cores and the cause of the 1258 bad weather conditions in Europe in 2013. So it is unlikely to be universally identified as the beginning of the Little Ice Age which was identified long before that date.
Mt. Salamas is reputed to have spewed twice as much sulphur into the atmosphere and stratosphere as Tambura.

Golf Charlie will confirm that the LIA is generally accepted as starting with the eruption of Mount Salamas in 1257 and ended when temperatures stabilised in the 1850s.

Nov 1, 2017 at 2:38 PM | Entropic man

Supertroll & Entropic Man, thank you for the update. Until 5 minutes ago, I had not heard of Mount Salamas.

If we can accept there was an MWP and LIA, how do we know what is the "normal" that existed in between, and what stopped happening to allow stabilisation in the 1850s by which time the Franklin Expedition was lost in the Arctic because sea ice had melted or frozen, only for one of the rescue ships to get stuck in the ice whilst searching? All confirmed by modern marine archaeology.
Two ships from the Franklin Expedition
https://en.m.wikipedia.org/wiki/HMS_Erebus_(1826)
https://en.m.wikipedia.org/wiki/HMS_Terror_(1813)
Is it just coincidence that HMS Terror was discovered in Terror Bay?

The search and rescue ship, found on the seabed by GPS, precisely underneath its last known surface position, as recorded by traditional navigation techniques.
https://en.m.wikipedia.org/wiki/HMS_Investigator_(1848)

The concept of LIA that I remember from before I was a teenager, included Dickensian images, Ice Fairs on the Thames etc paintings of the ice skating dutch etc

Mt. Salamas is reputed to have spewed twice as much sulphur into the atmosphere and stratosphere as Tambura.

Nov 1, 2017 at 3:13 PM | Supertroll

https://en.m.wikipedia.org/wiki/1257_Samalas_eruption

Having never heard of it before, I looked it up on Wikipedia, so I am not sure of the spelling. It is an interesting article suggesting the eruption might have ended the Medieval Climate ANOMALY, not the Medieval Warm Period.

(I associate the term Medieval Climate ANOMALY with William M Connolley, well documented for corrupting Wikipedia to suit his own Green Party, Hockey Team, Real Climate credentials. It could just be a coincidence that Entropic Man raised this anomaly in Wikipedia)

Obviously I have not seen any of the original research, but it does seem like another attempt to get rid/finish off the MWP. But it does not explain why the MWP started.

Entropic Man- I thought my recent comments would disappoint you. I really am sorry about that. Let me try to explain.

Your great strength is your command of the facts. I suspect you love facts and in some respects you are better than an interactive text book. That is meant as a complement. I believe you get great satisfaction from discussing a subject that involves assembling the theories, the experimental conclusions, the basis in terms of scientific principles and the conclusions and consequences. The more the whole thing fits together like the workings of a clock, the more satisfying it is. These blogs give you an opportunity to explain how the whole thing works. I believe you enjoy doing that, it give you much satisfaction. It helps others too, and it is a great gift.

I have spent my professional life problem solving and inventing stuff. The two are the same thing, really. Climate science is broken. You may not agree, from your perspective, but let us accept that some of it is controversial to say the least. That is why I was drawn to climate science a dozen or so years ago. It is a complex problem. I'm not trying to solve it, I don't have the expertise or the resources, but I'm trying to understand the nature of the problem just for my own satisfaction.

I apply the techniques that I have unconsciously applied to other problems throughout my career. I look at the big picture to try to see the wood and the trees. I look at details that may be inconvenient. I examine the "elephants in the room" that others prefer to ignore. I take into account why the researchers do things the way they do. I question most things and I don't believe everything I'm told. My source of satisfaction is finding a likely explanation that I believe is the truth.

In practical terms this usually results in a solution to a problem in the form of a new product or process. That will not happen with climate science but hopefully I will feel better about my assessment of the subject. I want to know whether we should be worried or not worried. I can expand on this if anyone is interested.

This is why my approach relentlessly probes under the stones. Why I question the received wisdom. I know it can be very disruptive, especially to you because you enjoy the "settled science" and I come along and stir it up.

I actually find your input very useful because you always present the "settled science" perspective and that is always a great reference point even if it turns out to be wrong. (sacrilege).

Nov 1, 2017 at 6:01 PM | Schrodinger's Cat
It has never been in my job description, but "troubleshooting" after something has gone wrong, is what I have been required to do regularly. When something breaks or fails for technical reasons, whether foreseeable or not, it is at least possible to determine what went wrong. When human error is involved, cover-ups and obstruction follow. It does not determine what went wrong, but is a good indicator for where to look.

I see a thread of human behaviour weave its way through this subject from the early days.

SC. Thank you for putting so eloquently why you appreciate EM's input, which matches my own. Like some others in different blogs, who serve the same function, he is sometimes an unappreciated resource. If you look at some threads and assess how many posts are from him or are responses to his. I have made this observation before and my conviction that it is true grows.
Of the many who I interact with here, he is one who, in earlier days, I would have wished to meet and have a drink with (unfortunately my travelling days have almost gone). Even though when he ventures into my specialities he can be almost exasperating.

It was in PNAS, so "probably" another example of looking for evidence after the conclusion was reached. (Not that I am doubting the consequences of Mt Samalas or the explanations, work etc)
http://m.pnas.org/content/110/42/16742
Source of the great A.D. 1257 mystery eruption unveiled, Samalas volcano, Rinjani Volcanic Complex, Indonesia

Significance

"Based on ice core archives of sulfate and tephra deposition, one of the largest volcanic eruptions of the historic period and of the past 7,000 y occurred in A.D. 1257. However the source of this “mystery eruption” remained unknown. Drawing on a robust body of new evidence from radiocarbon dates, tephra geochemistry, stratigraphic data, a medieval chronicle, this study argues that the source of this eruption is Samalas volcano, part of the Mount Rinjani Volcanic Complex on Lombok Island, Indonesia. These results solve a conundrum that has puzzled glaciologists, volcanologists, and climatologists for more than three decades. In addition, the identification of this volcano gives rise to the existence of a forgotten Pompeii in the Far East."

"These results solve a conundrum that has puzzled glaciologists, volcanologists, and climatologists for more than three decades." Does anyone remember climatologists openly puzzling about this for 3 decades?

Rhoda, golf Charlie, Supertroll

IIRC Tambora produced "the year without a Summer" in 1816. Salamas must have been a whopper!.

"Persistence of effect"

Orbital forcings were already pulling temperatures down by about 0.2C/century when Salamas erupted. That might be enough to explain the LIA on its own.

Salamas roughly coincided with a Southward expansion of the Arctic sea ice. Whether one caused the other we can argue later.

It was also the first volcano of a cluster , which would have prolonged the effect.

That sea ice expansion increased ice albedo and reflects more energy back into space. It would have extended, and perhaps amplified the volcanic cooling.

Add in the reduction in population (when the Black Death reduced the population by 1/3). The associated reduction in agriculture and regeneration of forest would have pulled CO2 levels down.

Just when things were really getting interesting the Maunder Minimum came along.

I doubt that the LIA had one.cause, It sounds more like a cluster/cascade effect with a number of contributing factors piled on top of each other.

I too have to admit learning much from EM. The LIA explanation above seems plausible to me, the volcano not entirely responsible but contributory. Note that at least there was an LIA, which is progress.

I do think, with all due respect, that there is a tendency towards certainty when to me it is not justified. Which brings me to that old American saying: " it's not what he doesn't know that worries me, it's what he knows for sure that just ain't so!"

Schrodinger's cat, golf Charlie

Thank you. You describe my approach to science very well. I regard the universe as a complex puzzle to be solved, and puzzles are fun! Being an old biologist helps. We apply physics, chemistry, geology, astronomy and Uncle Tom Cobbley to biological systems, which gives us a broad grounding across the sciences. It also gives us lots of experience of complex systems with multiple interacting variables.

Curious that we can look at the same evidence and come to such different conclusions.

I may have reacted a bit strongly to your earlier post, but it contained a number of statements which I cannot reconcile with the data.

I discount golf Charlie's hypothesis that it is all a conspiracy by the scientists to get grant money or a world government. (What kind of life led you to such a negative view of human nature?) I knew a number of the early investigators in my university days, and that was not what drove them. Besides, nobody can maintain a conspiracy to present false science for long. "The truth is out there" and any mismatch becomes very obvious when new workers try to replicate or build on earlier work. Remember how the "sceptic" dataset at Berkeley ended up giving the same result as all the others.

I wonder if you have misconstrued one of the basic positions taken by climate scientists. Your post suggests that we say

" Carbon dioxide concentration is the only forcing capable of causing climate change. All the rest can be ignored."

In fact the position is more complex.

" Of the many forcings acting on the climate system, increasing CO2 concentration is the only one currently driving global warming. The other forcings are monitored and if CO2 were constant their combined effect would be a small cooling trend."

Rhoda

I can't win, can I.

I follow the usual scientific convention of caution and sprinkle my posts with "maybe" or "possibly" or "probably" . I then get complaints that I am uncertain.

If I leave out the conditional modifiers in the interests of smoother conversation, then I am accused of being excessively certain.

For future reference, you may assume that in my head any and all statements I make are prefaced by

" This is conditionally true, based on the available evidence and data and subject to the usual confidence limits. If better evidence becomes available, any of this may be subject to change."

For one scientist debating with another this goes without saying, one of the underlying axioms which do not need to be explicitly stated.

I do not intend to say this every time I post, but a lifetime working in and around science has made it second nature.It is implicit in my thinking.

Entropic Man, why didn't the MWP and LIA appear in Mann's Hockey Stick if a great cooling event was being discussed for 30 years by climatologists, as the cause of the end of the MWP?

How much Science debating actually went on in the IPCC then, and how much goes on now? Real Climate Scientists ought to admit some form of mistake about Mann's Flatliner.

What caused the MWP, if it wasn't CO2 or a volcano?

Golf Charlie

You already know that I regard both the MWP and the LIA as noise on the long term cooling trend since 5000BP.

If you can give me a date for the beginning of the MWP it might be possible to investigate causes. There is evidence for a cooling trend around the end of the Roman Empire from 400AD. When did temperatures start going up again?

Remember how the "sceptic" dataset at Berkeley ended up giving the same result as all the others.

Nov 1, 2017 at 8:02 PM | Entropic man

How did Gergis reach the same conclusion?

Golf Charlie

Have you read this?

I doubt that the LIA had one.cause, It sounds more like a cluster/cascade effect with a number of contributing factors piled on top of each other.

Nov 1, 2017 at 7:22 PM | Entropic man

Why are you so sure Global Warming has a single cause, without knowing what caused the MWP?

"At University Level, is Meteorolgy still taught as a subject independent of Climate Science?"

I have no idea. I did a Physics at Imperial Geophysics/Oceanography at Southampton before postgrad Meteorology. Reading did teach Meteorology at undergrad level - the joy in filling in tephigrams.

Golf Charlie

"Why are you so sure Global Warming has a single cause, without knowing what caused the MWP?"

Because we can monitor the. system now.

We can measure all the potentially significant forcings; CO2, industrial pollution, volcanic pollution, ice albedo, land use, solar insolation and orbital forcing. When you examine the data, ncreasing CO2 is sufficient on its own to account for the observed warming.

All the others are neutral or slightly negative. If CO2 were constant all the other forcings would be producing a small cooling trend.

You still haven't given me a start date for your MWP. I've found a lot of disagreement, dates as early as 800AD and as late as 1050AD. Hard to suggest possible causes for something when you don't know when it starts.

Entropic Man, I did read it thank you. This extract does not help with its credibility as "Science"

‘Profound implications’

Michael Mann at Pennsylvania State University says that based on the analyses and modelling that he has done, increased solar output and a reduction in volcanoes spouting cooling ash into the atmosphere could have not only kicked off the medieval warming, but might also have maintained it directly.

Mann is also concerned that the dominance of medieval La Niña conditions now indicated by Trouet’s work might make it more likely that the current man-made warming could also put the El Niño system back into a La Niña mode, although most climate models so far had predicted the opposite.

“If this happens, then the implications are profound, because regions that are already suffering from increased droughts as a result of climate warming, like western North America, will become even drier if La Niña prevails in the future”, he says.

Not a lot of science

Have you read this?
http://notrickszone.com/2015/12/23/new-comprehensive-map-by-scientists-confirms-medieval-warm-period-was-real-and-global-climate-models-faulty/#sthash.UpX0d1RS.dpbs

"One of the biggest obstacles global warming alarmists have had to deal with is the inconvenient existence of theMedieval Warm Period (MWP), as there are reams of literature showing that this period was as warm or even warmer than today.

Yet, a number of global warming activists and alarmist scientists have tried air-brushing away its existence, or claimed it was a only a local North Atlantic phenomenon (just as Wikipedia does).

Now, thanks to the diligence of two German scientists, refuting or denying the existence MWP has just gotten a heck of a lot tougher. In fact from their results it is becoming clearer than ever that the MWP was real and worldwide."

Golf Charlie

Not a very useful reference.

Some sites warmer or colder, wetter or drier. Different sources give onset dates for the MWP anywhere between 800AD and 1100AD. End dates vary from 1150AD too 1550AD.

On that basis the MWP might have been 50 years long, or 750 years.

The temperature data is also wildly variable.

If no-one can agree on when it started, when it it ended or what the temperature was, did the MWP exist at all?