quote:

Originally posted by Mambit_Giggler:
.

I should get paid for this! Dredging up my back of a postcard I found the following answers.

1) For two centuries medieval temperatures were higher than present, such that vinyards flourished in the North of England. There were of course no cars or planes then. Greenhouse gases due to man’s activities were infinitesimal at that time.

http://www.realclimate.org/index.php/archives/2006/07/m...th-and-english-wine/

QUOTE
Since 1977, a further 200 or so vineyards have opened (currently 400 and counting) and they cover a much more extensive area than the recorded medieval vineyards, extending out to Cornwall, and up to Lancashire and Yorkshire where the (currently) most northerly commercial vineyard sits. So with the sole exception of one 'rather improbably' located 12th Century Scottish vineyard (and strictly speaking that doesn't count, it not being in England 'n' all…), English vineyards have almost certainly exceeded the extent of medieval cultivation
UNQUOTE

As for medieval temps higher than today try:- (spoilt for choice)

http://en.wikipedia.org/wiki/Image:2000_Year_Temperature_Comparison.png

As you can see it’s warmer today. A lot warmer.


2) During the period 1645–1715, right in the middle of the Little Ice Age, solar activity as seen in sunspots was extremely low, with some years having no sunspots at all. This period of low sunspot activity is known as the Maunder Minimum. The precise link between low sunspot activity and cooling temperatures has not been established, but the coincidence of the Maunder Minimum with the deepest trough of the Little Ice Age is suggestive of such a connection

Back to the present day:-

“Scientists have examined various proxies of solar energy output over the past 1,000 years and have found no evidence that they are correlated with today's rising temperatures. Satellite observations over the past 30 years have also turned up nothing. ‘The solar contribution to warming... is negligible,’ the researchers wrote in the journal Nature.” (Anjana Ahuja, ‘It's hot, but don't blame the Sun,’ The Times, September 25, 2006)

[3) The current period of global warming started 150 years ago, 50 years before cars and planes were invented. Global temperature actually dropped between 1940 and 1975 at a time when CO2 levels continued to rise. ]

I can’t do any better than quote a chap by the name of Tamino who investigates temperatures.

QUOTE
Fit a trend line 1940 to 1975; the slope is slightly negative (cooling). Now fit a trend line 1950 to 1975. The slope is slightly positive (warming). And that is *not* 30+ years of cooling. It’s more correct to say that it cooled from about 1944 to 1951 (7 years), then levelled off for 24 years.
Then there’s the fact that neither the cooling 1940-1975 nor the warming 1950-1975 is statistically significant. It’s not cooling or warming; it’s fluctuating.
UNQUOTE

However during that period levels of solar eruptions fell. Graphs of solar activity correlate better with global temperatures than graphs of levels of CO2.

If you can show peer-reviwed science from a reputable journal showing this I'd be very surprised.

http://en.wikipedia.org/wiki/Image:Sunspot_Numbers.png

Residual warming due to the sustained high level of activity since 1950 is believed responsible for 16 to 36% of recent warming (Stott et al. 2003).

So that's 64% to 84% due to other reasons. CO2 ring a bell?

4) The troposphere should be warming if greenhouse gases are trapping the sun’s heat. It isn’t.

This canard was based on faulty measurements and when the problem was resolved it showed that the troposphere was warming in line with predictions. For those who don’t know, the troposphere is the lowest part of the atmosphere i.e what we’re walking and breathing in.

http://www.msnbc.msn.com/id/8917093/


http://en.wikipedia.org/wiki/Global_warming

QUOTE
Temperatures in the lower troposphere have increased between 0.12 and 0.22 °C (0.22 and 0.4 °F) per decade since 1979, according to satellite temperature measurements.
UNQUOTE

What’s above the troposphere is the stratosphere and the boundary between them is called the tropopause. Due to GW the tropopause has shifted upward by 900 feet in two decades.

http://www.ucsusa.org/global_warming/science/Fingerprints.html


5) Long term records going back 600 million of years show rises in CO2 levels lag global temperature rises by 800 years thus showing rising CO2 levels are an effect of warming not a major cause. Reason being it takes 800 years to warm the oceans. Warmer oceans emit more CO2.

The thermal capacity of water is massive. Indeed only liquid ammonia has a greater capacity. i.e.

http://hypertextbook.com/physics/thermal/heat-sensible/


Here’s Realclimate’s old 2004 article on the 800 year lag.

http://www.realclimate.org/index.php?p=13


Here’s their latest 2007:-

http://www.realclimate.org/index.php/archives/2007/04/t...etween-temp-and-co2/

and from:-

http://www.medialens.org/alerts/07/0313pure_propaganda_the.php

Good link that one. Someone’s done their homework.

QUOTE
The best current explanation for the lag of 800 years is that this is how long it takes for CO2, absorbed by the ocean in an earlier warm period, to be "flushed out" at the end of an ice age. Once that CO2 has been released into the atmosphere its heat-trapping properties as a greenhouse gas lead to even stronger warming: an example of positive feedback. (See Caillon et al., 'Timing of Atmospheric CO2 and Antarctic Temperature Changes Across Termination III,' Science, 14 March 2003: Vol. 299. no. 5613, pp. 1728 - 1731)
Professor Severinghaus summarises:
"In other words, CO2 does not initiate the warmings, but acts as an amplifier once they are underway."
UNQUOTE

6) CO2 emissions from human activity are only a small proportion compared to emissions from natural sources of CO2 & 95% of greenhouse gas is water vapour.

Before man came on the scene the Earth was in dynamic equilibrium. Now with 7gig tonnes of carbon (7*3.667 = 25,000,000,000 tonnes of CO2) dumped into the air every year it has a genuine effect on the planet.

Have a look at this history.

http://www.aip.org/history/climate/co2.htm


Carl Wunsch below:-

QUOTE
as is true, that carbon dioxide is only a small fraction of the atmospheric mass. The viewer is left to infer that means it couldn’t really matter. But even a beginning meteorology student could tell you that the relative masses of gases are irrelevant to their effects on radiative balance.
UNQUOTE



Ah in the old days I used to think “If they want to believe garbage that’s their own business” then I noticed what I was standing on – the planet Earth. Their thinking will affect me and my relative’s futures! Gotta do something about it. SO I track the bull and try and debunk it by yes cutnpasting from the best links I can find. There was a thread about multiple feedbacks here not so long ago which I found very worrying. After months of debunking tripe I thought I’d be tired of this but au contraire.

Dear Mambit – I hope that’s cleared your confusion. Regards.

Suricat

quote:

Water evaporation below boiling point takes the equivalent of the latent heat of evaporation from the 'water' medium. There is no elevation of temperature to boiling point at all. The evolution of water vapour below boiling point is 'simplistic' and 'opportunistic'

OK I'll take your word for it. I'd assumed otherwise.

quote:

I've made other calculations that you may be interested in, but I don't have time to post just yet

If relevant then yes please

SoM

quote:

quote:
and (if the model doesn't collapse in a numerically unstable heap) the 4W should go away for a bit.



So from what you say I assume this hasn't been tried.

Probably it has in an offline radiation model. Trying it in a full model might work, but also in going out of bounds of physical realism it might produce a runaway effect in one or more of the gridcells.

Suricat

quote:

It sounds like the model needs a subroutine that adds temperature increase with opacity increase, and it also looks as though a physical parameter for water vapour 'latency' is missing.

The temperature increase would come in time as the amount of energy absorbed from the sun outweighs the amount of energy radiated by the earth (due to the additional opacity of the extra CO2). The suggestion of immediately adding 1C was a device to demonstrate that you aren't dependent on running 100 years to show an effect.

In the example I've given, I guess creation of the extra water vapour (after adding the artificial 1C of warming) will cool the atmosphere - I don't know how much. I understand a 1C warming increases water vapour on average by about 7%, but don't know how much energy this needs and how much cooling would result. Of course the models deal with the energy of evaporating/condensing water vapour in a physical way.

quote:

Does the model use a 'production programming' type programme construction?

Not sure what you are asking.

Steve_M.

Em... Far be it for me to teach my Grandmother to 'suck eggs', but some things aren't right here.

Quote.
In the example I've given, I guess creation of the extra water vapour (after adding the artificial 1C of warming) will cool the atmosphere - I don't know how much.
EOQ.

Water vapour doesn't cool the 'troposphere' (which is where it mostly exists) it heats it. In fact it heats the troposphere a darned site more than CO2 does. Water vapour traps (by 'optical diffusion') IR and sends it every which way. Thus, elevated IR levels in the troposphere. Do we agree on this, or do I respond to a 'typo' here?

Above the troposphere water vapour is minimal.

Quote.
I understand a 1C warming increases water vapour on average by about 7%, but don't know how much energy this needs and how much cooling would result.
EOQ.

You could also ask 'how long is a piece of string'. However, without more metrics I couldn't tell you, but the answer is in the water and air temperature at the interface, the atmospheric pressure at that point, water salinity and vapour pressure (vapour pressure aberration would be due mostly to humidity level at the interface [e.g. saturation] ). Increased wind speeds improve evaporation by effecting a reduction in saturation at the interface. I don't know of any 'average percentages', but perhaps your quote infers the use of 'scenarios' within the model's programme.

Evaporation of a liquid below it's boiling temperature is unforced and requires no energy input. That is to say the evaporation event is in itself 'opportunistic'. Kinetic energy within the liquid causes a molecule of the liquid to escape as a gas. The energy to do this is supplied by the liquid itself and the result is that 1 mole of the 'latent heat of evaporation' for the liquid is lost from the liquid to the emergent gas molecule. Sorry if that seems long winded, but I can't think of a better way to describe it. However, natural evaporation causes refrigeration of the liquid 'without' an external energy input.

I'd better wait for a return post before I write more, but in the mean time.

Quote.
The temperature increase would come in time as the amount of energy absorbed from the sun outweighs the amount of energy radiated by the earth (due to the additional opacity of the extra CO2). The suggestion of immediately adding 1C was a device to demonstrate that you aren't dependent on running 100 years to show an effect.

EOQ.

I must confess that I'm not familiar with the model to which you refer (unless it's a theoretical one on 'how to reduce computer runtime loading').

Quote.
Not sure what you are asking.
EOQ.

So it's a spreadsheet and not a computer runtime programme?

Regards, suricat.

Son of Mulder.

Looking again at the IPCC 4th report FAQ 1.1. Figure 1 and the 78w/m^2 evapo-transpiration has made me realise that there is possibly an easy way to evaluate the mean global temperature. Would this be 'relevant'?

Regards, suricat.

Suricat,

I'm no modeller but given the iteration used in the time domain calculation of grid-box parameters in models, I really think it's nearer a computer program than spreadsheet. You can't do that sort of iteration in a spreadsheet without using macros.

I might be getting the wrong end of the stick here but: The global trend is for an increase in absolute humidity, but no trend in relative humidity (UK Met Office*). This is what would be expected from warming - changes in air circulation would not reasonably account for that observation (as far as I know).

*Met Office HCTN 71 pdf, http://www.metoffice.gov.uk/research/hadleycentre/pubs/HCTN/HCTN_71.pdf

Doh!

I should have been saying specific humidity - not absolute humidity.

Suricat,

quote:

Looking again at the IPCC 4th report FAQ 1.1. Figure 1 and the 78w/m^2 evapo-transpiration has made me realise that there is possibly an easy way to evaluate the mean global temperature. Would this be 'relevant'?

Yes please, I'm always keen to find new insights particularly if it can bypass lots of fog (metaphorically).

Son of Mulder.

Hope leokor doesn't mind because this describes a lot of what I see as the metaphorical 'greenhouse' and he usually tries to disprove any 'greenhouse' theories.

Remember that this is only my theory and conjecture!

I'm sure most would agree that almost no 'black body' infrared (IR) escapes the troposphere from near the ground (boundary layer) and that the black body radiation level signifies our average global temperature.

The major carrier of heat from the surface region is water vapour (WV). Some IR eventually makes it through the troposphere, but WV - as the major 'transport' mechanism - is an excellent choice for use as a metric of IR (with some adjustments) and therefore a means to calculate global average temperature.

Are you still interested?

Regards, suricat.

CobblyWorlds.

I have no such 'model' experience either, but previous computer 'assembly language' use gives me some small insight. The problem with these 'high level language' applications is that you never know if they are using data from an application, within an operating system, within machine code, or just machine code (perhaps an 'assembly' of sorts [either with or without a 'compiler', or 'translator', to say 'FORTRAN', 'Pascal', even 'basic' etc] ).

Your link gives me problems in the 'credibility stakes'. I got as far as page 4, the paragraph between equation 1 and equation 2, and their "assumptions". I don't see how this can be accurate.

Regards, suricat.

Right, I get what you mean Suricat,

I don't know if this link will work, but click here and you should see the code viewer interface for NASA's Model E GCM. The homepage is here. as you can see, it's programmed in Fortran.

Son of Mulder.

Sorry for the split postings, but I've been really pushed lately (no excuse I know, but I've at least given you the reason).

To continue, if you are not looking for an actual temperature it's really easy. The total column water vapour (WV) mass figure contains all the WV that has evolved during approximately the previous ten days, including anything that happened to it since its evolution both at ground level and in atmosphere. Thus, the average of total column WV for each grid-square gives the current global signature of temperature with inclusions of about the last ten days events, and a bit of clutter that is pretty constant.

This method would be quite easy to use for showing global temperature changes if you don't need to show the actual scalar temperature, but some care must be taken with the method of data gathering and the continued use of 'only' that method for results that are verifiably comparable with one-another.

If you want to show degrees Kelvin it naturally gets more complicated. The 'clutter' has to be removed from each grid square before averaging, all data must be gathered at pretty much the same Lunar and Solar 'Tide' height (that could be awkward), and then a standard for the 'temporal life time' of the remaining latently active WV must be set against a simultaneously known global average temperature. The way to set the system standard is to divide the w/m^2 of black body radiation from the known global temperature into the Joule requirement for evaporation of the (now 'clean') total active WV column mass.

Once you arrive at this standard, any deviation in (clean) WV column mass can be seen as a +tive, or -tive, forcing in Joules, or w/m^2, or as a recovery from an earlier forcing. Above all, because it's in w/m^2 it can also be calculated as 'black body radiation', added to your 'standard' (in 'black body radiation') and a new 'average global temperature' can be arrived at.

Is that simple, or is that simple? All we need to do now is look for usable data!

Regards, suricat.

PS. Forgot to remind you in this post that this is only theory.

CobblyWorlds.

Thanks for the link, I've been contemplating for some time now as to whether or not I should 'take the plunge' into one of these weather models.

The html 'code interface' looks like a good tool. A better graphic to show the programme structure would be a 'flow diagram' with FORTRAN, but I didn't find one on NASA's site. Perhaps one exists somewhere, but I didn't find it.

As I said before, "I have no such 'model' experience either, but previous computer 'assembly language' use gives me some small insight." and I notice that (in your link) the 'compiler' has flagged a couple of warnings in the model you offer. These are warnings of inability to set 'grid' and 'boundary', thus I presume the model is not set to 'run' (notwithstanding that a 'dummy' stratosphere is already 'plugged in'). I've saved the page for future reference.

You've made no reference to my incredibility of your Met Office link? If the physics that these models are being programmed with is incorrect, how can the models respond with confidence?

Regards, suricat.

Suricat,

I assume it's this para?

"RH represents relative humidity, e(TBdB,p) is vapour pressure as a function of dewpoint temperature and pressure, and eBsB(T,p) is the saturation vapour pressure as a function of temperature and pressure. Uncertainty in relative humidity therefore can be determined from the root of the sum of squared error in vapour pressure and saturated vapour pressure.

*The dependence upon air pressure is very weak, so we can make the reasonable assumption that surface air pressure is constant in our analysis of vapour pressure (Buck 1980).

*We also assume that the scale height of water vapour is constant (Stephens, 1990), meaning that we can use changes in total column water vapour as a proxy for changes at
the surface. These assumptions mean we can make approximations to specific humidity (q) and total column water vapour (w) as follows:..."

I have placed asterisks by the assertions I guess you refer to, they look OK to me. But as I have not read either the Buck or Stephens references it's hard for me to comment too much.


It's also ages since I read that paper (late last year I think). Bear in mind that the main purpose of the paper is to examine uncertainty, not to establish facets of the observations of humidity trends. However it's a freely available source that does demonstrate the behaviour expected with a change in WV due to warming (i.e. not due to circulation changes). See figs 2 and 4 and bullet 1 of "Key outcomes/non technical summary" page 2.

I've not got time to enter into a quantitative discussion of the paper, but I do consider it supprts my use of it in a qualitative sense.

What specifically did you have issue with?

Suricat,

quote:

To continue, if you are not looking for an actual temperature it's really easy. The total column water vapour (WV) mass figure contains all the WV that has evolved during approximately the previous ten days, including anything that happened to it since its evolution both at ground level and in atmosphere. Thus, the average of total column WV for each grid-square gives the current global signature of temperature with inclusions of about the last ten days events, and a bit of clutter that is pretty constant.

But how do you seperate out the effect due to convection because that is seperate from the latent heat mechanism and IR. Also aren't you assuming a functional relationship between IR & latent heat transport which is not possible if convection is a 3rd variable that would act dependent on surface topography as well a delayed reaction to IR & latent heat effects in other places ie wind.

CobblyWorlds.

Well look at that! You've marked the points perfectly. Yes, it's the physics that disturbs me on these points. Though I'll admit that the "assumptions" were fairly well defined in my reference.

I've now read the full content of your link and note that it is recognised that there is insufficient definition for accurate analysis to produce the data required by interpretation of available data (the writer realises that it's like 'reading a multimeter at less than half full scale deflection' [apology for the engineering terminology] ).

The problems I have with these "assumptions" are:
A). "The dependence on air pressure is very weak", 'but only on the saturation curve' (this has little, or nothing, to do with specific humidity, or relative humidity, in a dynamic system). However, it 'is' very relevant at 'boiling point'.
B). They also assume that the scale height of water vapour is constant. How, why and 'wrong' (the Solar and Lunar atmospheric tide alone alters atmosphere altitudes almost constantly).

It is apparent to me that your reference link is to a 'feasibility study' for 'metrics'. Why did you post this? I'm not looking for any motive here, I'm just curious because I don't see any obvious logical connection (no, don't tell me I'm approaching premature senile dementia already?).

OK, if I am, tell me!

Best regards, suricat.

Suricat,

Firstly, as I say you'd need to read the references to really get to grips with why they make the assumptions. The assumptions are made based upon the work of others, which is why they're referenced. I did write "as I have not read either the Buck or Stephens references it's hard for me to comment too much." That is still the situation.

However with regards your points:

A) Where (aside from the Mesosphere - irrelevant) do climate processes cause temperatures to get anywhere near boiling point?

B) You write "How, why and 'wrong' (the Solar and Lunar atmospheric tide alone alters atmosphere altitudes almost constantly)." Firstly as I said above, with regards How/Why - you need to read the reference. Wrong? Not so, based on your reasoning. The change in atmospheric height relates to the tenuous upper atmospheric layers. Something like 90% of atmospheric mass is below 15km, if tidal forces were not overridden by pressure then we'd see a trend in weather - I'm not aware of one - can you show that there is? As the amount of WV falls off massively in the troposphere, and that's not substantially impacted by tidal forces, I don't see how tidal forces are a factor.


I keep reading that the behaviour of water vapour is such that RH stays roughly constant while SH increases - implying temperature as the causal mechanism. That is the only publicly available free to down load document I have that backs that up.

As I said above "See figs 2 and 4 and bullet 1 of "Key outcomes/non technical summary" page 2." So yes the aim of the paper is not to study the issue I am using it for. BUT it does contain data that supports the conclusion that a warming is driving the observed trends in WV. From my reading the errors involved in readings of RH/SH are not so great that they undermine that usage.

PS Got the refs for you.

Here is Buck 1980, it's cited by 132 other papers.

Here is Stephens 1990, it's cited by 47 other papers.

Due to the number of citations I'm not reading them - too busy. They're accepted by both writers and reviewers of the papers citing them and if they can't see a problem I won't be able to find one (from experience if I do think there's a problem then it'll be more down to my understanding being flawed).

Son of Mulder.

My quote.
Thus, the average of total column WV for each grid-square gives the current global signature of temperature with inclusions of about the last ten days events, and a bit of clutter that is pretty constant.
EOQ.

Sorry, that was very badly worded (but I was hurrying so as not to turn into a pumpkin after C4's midnight deadline).

This should read "Thus, the average of total column WV for all grid-squares gives the current global signature of temperature with inclusions of about the last ten days events, and a bit of clutter that is pretty constant." as it makes more sense when I left out the fact that you must make an average of all the grid squares for the 'global' signature of temperature.


Quote.
But how do you seperate out the effect due to convection because that is seperate from the latent heat mechanism and IR. Also aren't you assuming a functional relationship between IR & latent heat transport which is not possible if convection is a 3rd variable that would act dependent on surface topography as well a delayed reaction to IR & latent heat effects in other places ie wind.
EOQ.

If we accept the IPCC's figures the ratio between transport by latent heat and transport by thermals is 13 : 4 respectively. I don't see that this ratio would change much at all. I also don't see that the altitude for the 40w/m^2 window with IR is going to reduce any time soon either.

I think that the local topographic problems will persist at their locality, but the clarification of my wording should resolve this.

Yes. There is a direct link between WV and IR. 'IR in' causes thermal increase and 'IR out' causes thermal reduction. IR heats water and its surroundings to produce WV, and when WV condenses it gives up its latent heat of evaporation to heat its surroundings which in turn radiate IR and cool.

Best regards, suricat.

CobblyWorlds.

Ha! Probably more like my understanding is flawed! I still can't understand how sea level would be affected by Solar and Lunar Tide, but the atmosphere isn't.

A). The reference to boiling point was a physical reference to liquid water and not the atmosphere. Sorry if I misled you.

B). I see you are not a sailor. I've sailed a bit and I'm sure many other sailors would agree that the weather often alters with the tide (more than just the 'wind over tide' effect). I can't find any online links to this though (and that includes the RYA).


I think we are actually agreeing on this subject, but looking at it from different perspectives. Thanks for the latest links, I've saved them to read through when I get the chance (I thought RMS was totally an AC - DC electrical 'power' thing).

Quote.
I keep reading that the behaviour of water vapour is such that RH stays roughly constant while SH increases - implying temperature as the causal mechanism. That is the only publicly available free to down load document I have that backs that up.
EOQ.

RH (relative humidity) is a ground level measurement of air saturation level with WV and is expressed as a percentage of 'full air saturation' for the recorded temperature. As air temperature changes, the possible WV mass for 'full air saturation' also changes altering any percentage value. This is in continual flux. However, If you, rightly, imply that there is no 'long term trend' for changes in RH. It isn't surprising because 1 atmosphere pressure is constant and the vapour pressure for water is constant. Any temperature 'trend' at ground level is largely unseen due to the heat captured by water in evaporation to WV, the buoyant gas then invisibly 'spirits' the heat into the troposphere causing havoc with IR in the process (but all life depends on this).

SH (specific humidity) is the WV mass as a ratio with the dry air mass concurrently occupying the same space. It offers no metric for temperature, pressure, or saturation levels and so is not commonly used for weather reporting.

I think we see SH being used here to quantify 'total column WV mass' and I think that its the increase of this to which you refer the cause as temperature. I've been saying the same sort of thing for ages, only I don't seem to get the language right. However the IPCC's AR4WG1 rendition is another free source. See AR4WG1_Ch03.pdf page 270 (36 of 102) section 3.4.1.4 The Tropopause. They claim that "Over 1979 to 2001, tropopause height increased by nearly 200 m (as a global average) in ERA-40, partly due to tropospheric warming plus stratospheric cooling (Santer et al., 2004).". This is a WV incursion into higher altitudes thing (thus greater atmospheric mass of WV).

Regards, suricat.