Thanks Marcus.

The fact is that I've never hold myself out as some sort of guru. Everyone knows I am not a professional scientist or can easily find out.

What I do is spot inconsistencies between observations and established theory. There are so many that that is not difficult. I then formulate a scenario that could account for the observations and put it up for challenge. Sometimes I make incorrect assertions which if pointed out then results in an adaptation of the scenario but I will persist until such adaptations become untenable and thereupon I withdraw or approach the issue from another angle.

I am actually using the other participants here as a quality control service for a climate description that is steadily increasing in precision and scope.

It has been surprising how little of substance there really is behind the assumptions of AGW.

I think that the reason I irritate Gandalf and some others is that I present a challenge to their pretensions of AGW guruhood.

But, that's not to belittle them?

---

Gandalf asked:

"If there were liquid surfaces then by what mechanism did the ice form and extend to cover much of the oceans away from the tropics?"

We have seen recently that a quiet sun quickly results in a negative polar vortex, more equatorward/meridional jets, increased global cloudiness and albedo with less solar energy penetrating the oceans.

There is no reason in principle to deny that from time to time a long period of quiet sun combined with astronomic influences could facilitate such a large reduction in solar input to the oceans that ice from the two poles could spread beyond the subtropics and even in extremis result in a snowball or slushball Earth.

The recovery would arise from a simple reversal of the same factors.

We are all guests visiting this site! We are all entitled to our opinions, and raise questions resulting from the incomplete knowledge of our climate system - and that doesn't trouble me. It is actually very easy to differentiate between this forum and 'proper peer-reviewed scientific study' (is there a definition of what counts as that?!). Belittling those making a genuine attempt to understand the science and, through debate, discussion and argument, helping to advance the knowedge of many of us interested non-specialists is not very constructive. Many of today's climate scientists are in highly specialized disciplines: who is there left entitled and qualified to give us a comprehensive overview of climate science, AGW and climate prediction?

I think you know what I mean when I use the word 'Guest' Marcus. For the avoidance of doubt I mean those not registered on the TWO Forum and therefore visiting, i.e. reading but not contributing.

According to the dictionary "belittle' means to make someone or something unimportant.  That is hardly the applicable label is it?  You make a strange observation about "all entitled to our opinions" and then in the same post you imply that I am not entitled to mine?

I stand by my observation.  Stephen implies a level of confidence and certainty that is entirely unjustified and misleading.

You will see from his posts that his stance is anything but "a genuine attempt to understand the science" and entirely about belittling the entire science of AGW and those who accept it.  If you need proof just read his follow up post in response to yours.

 

---

Devonian asked:

"But, that's not to belittle them?"


How can acknowledging someone else's ability to improve my work constitute 'belittling' ?

Gandalf asked:

"If there were liquid surfaces then by what mechanism did the ice form and extend to cover much of the oceans away from the tropics?"

We have seen recently that a quiet sun quickly results in a negative polar vortex, more equatorward/meridional jets, increased global cloudiness and albedo with less solar energy penetrating the oceans.

There is no reason in principle to deny that from time to time a long period of quiet sun combined with astronomic influences could facilitate such a large reduction in solar input to the oceans that ice from the two poles could spread beyond the subtropics and even in extremis result in a snowball or slushball Earth.

The recovery would arise from a simple reversal of the same factors.

Stephen, you are doing what you did with the swimming pool analogy - missing the point again.

The point I was making was that your assertion that some open water alone was sufficient to reverse the 'snowball Earth' state was clearly incorrect. 

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Gandalf said:

"The point I was making was that your assertion that some open water alone was sufficient to reverse the 'snowball Earth' state was clearly incorrect."


I didn't exclude other factors. I just pointed out that they do not seem to be essential. How about you explaning why you think solar shortwave into the oceans could NOT be sufficient.

I think that the reason I irritate Gandalf and some others is that I present a challenge to their pretensions of AGW guruhood.

You irritate me - and others - because, inter alia:

• you assert a level of certainty in your arguments that you deny to anyone else.


• you are not prepared to support your theories with hard facts


• You scoff at the case for AGW when you have scant evidence for your position


• You are inclined to overdo the arrogant self-publicising

The bold part of your post is just a futile attempt to play back my use of the word 'guru'.  I used the word adivsedly - you are just using it for effect - again,

As for challenge - please do demonstrate how your theories prove the work of thousands of climate scientists wrong and how the data supports your theories. If you were capable of doing this in any sort of reasoned, supported and sensible way then I might be interested.

 

---

Devonian asked:

"But, that's not to belittle them?"


How can acknowledging someone else's ability to improve my work constitute 'belittling' ?

My bad. I guess when you say "I think that the reason I irritate Gandalf and some others is that I present a challenge to their pretensions of AGW guruhood." it's acknowledging someone else's abilty to improve your work

Anyway, it's nearly time to watch the you know who

---

Gandalf said:

"The point I was making was that your assertion that some open water alone was sufficient to reverse the 'snowball Earth' state was clearly incorrect."


I didn't exclude other factors. I just pointed out that they do not seem to be essential. How about you explaning why you think solar shortwave into the oceans could NOT be sufficient.

Well that's not what you said. If you are changing or correcting your original post then that's fine.

How does solar radiation affect ice covered ocean?

---

Gandalf:

Please calm down. I have put up with far more from you than I have subjected you to (in my humble opinion).

Most people here know full well that your rant is unfair.

I have posted lots of links and data where it is available in support of the scenarios that I put forward.

I've also made it clear often enough that whatever I say is open to challenge. I am here specifically to receive challenges and consider them. I never promised to give in without a fight because that is the best way for both sides to learn.

Why do you think my discussions with StuN are calmer than mine with you ? He knows a lot of technical stuff that I don't and puts it forward constructively. All you can do is tell me that the people you choose to believe know more than me so I should shut up even though the people you believe are unable to deal with the inconsistencies in their own performances.

"How does solar radiation affect ice covered ocean?"

You have yet to establish that such a complete coverage on the Earth is possible in the first place.

If it did happen then raised insolation (for whatever reason) at the equator would start to melt the ice surfaces more than they would refreeze at night with an exponential effect. You do not need to invoke CO2 or volcanic activity but once present they would add to the effect.

"How does solar radiation affect ice covered ocean?"

You have yet to establish that such a complete coverage on the Earth is possible in the first place.

If it did happen then raised insolation (for whatever reason) at the equator would start to melt the ice surfaces more than they would refreeze at night with an exponential effect. You do not need to invoke CO2 or volcanic activity but once present they would add to the effect.

Once you have an ice/slushball you have to establish whether it can escape just by normal variations in solar output. Is there any evidence to suggest that it can? Of course we've got evidence that GHGs could maybe kick start it (despite all the uncertainties), so is there anything else to put on the table?

Gandalf:

Please calm down. I have put up with far more from you than I have subjected you to (in my humble opinion).

Most people here know full well that your rant is unfair.

I have posted lots of links and data where it is available in support of the scenarios that I put forward.

I've also made it clear often enough that whatever I say is open to challenge. I am here specifically to receive challenges and consider them. I never promised to give in without a fight because that is the best way for both sides to learn.

Why do you think my discussions with StuN are calmer than mine with you ? He knows a lot of technical stuff that I don't and puts it forward constructively. All you can do is tell me that the people you choose to believe know more than me so I should shut up even though the people you believe are unable to deal with the inconsistencies in their own performances.

Stephen

I am not a scientist but I am capable of reading and learning.  I don't engage you in debate in your technical interpretations because it is not my field of expertise, but I will highlight inconsistencies or errors when I see them.

You and I fall out because I don't like the underlying tone of some of your posts.  Your stance that AGW is just insignificant and can be ignored is so far away from everything I read about climate change that my presumption about everything you say is that it is rooted in your, IMHO unreasonable, disbelief.

A good start would be a little more respect for the many climate scientists and their work and conclusions. I accept that everyone is entitled to their opinions but rubbishing and being disrespectful of those who have devoted their labours to understanding the climate stystem is never going to gain my respect or tolerance...

Maybe I have misinterpreted you? 

---

"How does solar radiation affect ice covered ocean?"

You have yet to establish that such a complete coverage on the Earth is possible in the first place.

If it did happen then raised insolation (for whatever reason) at the equator would start to melt the ice surfaces more than they would refreeze at night with an exponential effect. You do not need to invoke CO2 or volcanic activity but once present they would add to the effect.

If you start with open ocean, away from the polar regions, and progressively the open water freezes all the way to the tropics and possibly beyond, then clearly your mechanism is being overwhelmed by other forcings. If so, the mere fact that there is a small proportion of open ocean is not sufficient to reverse the process.  Some other compensating forcings must be at work.  My understanding of the Snowball Earth theory is that steadily increasing levels of CO2 are the primary driver. If the oceans are mainly ice covered then they are not able to act as a CO2 sink, which puts a progressively larger amount of CO2 into the atmosphere over time.  Of course there will be other forcings, perhaps relating to the Earth's orbit etc.

Your statement doesn't make sense for this reason.  

---

"then clearly your mechanism is being overwhelmed by other forcings"

Why so? All that is necessary is for the amount of energy entering the oceans to become reduced for whatever reason. Why need falling CO2 levels be the cause as opposed to orbital changes, solar variability altering the jets, volcanic aerosols etc .

Yet not all are convinced it ever happened.




"Maybe I have misinterpreted you?"

Yes. You are oversensitive on behalf of climate professionals.

"Once you have an ice/slushball you have to establish whether it can escape just by normal variations in solar output. Is there any evidence to suggest that it can?"

Have you established that it cannot ?

And what do you mean by 'normal'. It has happened so rarely if at all that it is way beyond the realms of 'normal' in every respect.

There's a lot of reversing the burden of proof going on these days.

"Maybe I have misinterpreted you?"

Yes. You are oversensitive on behalf of climate professionals.

Yes, perhaps - but you are obstinately and relentlessly under-sensitive Stephen.

Challenge is one thing, rudeness and disrespect quite another - as you are fond of pointing out to me. 

---

"Once you have an ice/slushball you have to establish whether it can escape just by normal variations in solar output. Is there any evidence to suggest that it can?"

Have you established that it cannot ?

And what do you mean by 'normal'. It has happened so rarely if at all that it is way beyond the realms of 'normal' in every respect.

There's a lot of reversing the burden of proof going on these days.

Hang on, you claim that the sun could end a global glaciation, but the burden of proof is on me? Your hypothesis, your burden of proof. Have at it.

To get you started, I mean 'normal' in terms of what we know about orbital cycles and changes in the sun's output.

The sun is the source of all energy in the system.

The starting point is that whatever happens is a consequence of more energy or less energy entering the system.

If you propose that the Earth cannot become a snowball without reducing CO2 or recover without increasing CO2 then that is your hypothesis.

While we are about it how sure are we that it did ever happen ?

The sun is the source of all energy in the system.

The starting point is that whatever happens is a consequence of more energy or less energy entering the system.

If you propose that the Earth cannot become a snowball without reducing CO2 or recover without increasing CO2 then that is your hypothesis.

While we are about it how sure are we that it did ever happen ?

We are moderately sure that 'slushball' conditions happened with evidence of cyclical glacial deposits in places that would have been at low latitude at the time. The evidence for a complete snowball is patchy at best.

I never said the Earth cannot become a snowball without reducing CO2. Where did I say that? Reduced levels of GHGs would help for sure but the initial trigger is more likely to be continental configuration (most continents near the equator), changes in ocean circulation, orbital cycles and a slight tendancy towards glaciation anyway as the sun was dimmer 600 million years ago.

I would certainly not say that only large concentrations of greenhouse gases are needed. To simplify, let's say you need 100 units of forcing to get out of a slushball state. Your GHGs have built up to 75 units (arbitrary number) but can't really get any higher. You need to wait for other conditions, solar output, orbit etc to be more favourable and provide the extra 25 units. As soon as it starts melting you probably get a dump of methane into the atmosphere providing an additional kick.

That's how I see it anyway. I wonder if anyone will attempt to run this on a modern model with all their chemistry and biosphere components.

 

BTW Stephen, did you answer my original question that led to this discussion? I asked "Are you saying that if we had the oceans but not GHGs the Earth would be about as warm as it is now?"

Just to clarify, this means imagine that water vapour and clouds have no radiative effects either. Essentially dealing with the approximation that leads to the conclusion that the greenhouse effect adds up to about 33C.