Geoffwood

Mrs Trellis hi. Thanks for the reply. You say, "Won't changing any single one of your chosen start-points negate everything you say?" Which ones are variables, Mrs Trellis? I am making a direct comparison. My point is to evaluate the total effect of having an atmosphere upon surface temperatures. It is less than people believe. Do you have a problem with using a parallel experiment for validation? You have made an excellent point about start up conditions because Trenburth's energy diagram fails completely if we alter the start conditions. But we'll get to that in due course.

Interitus, thanks for your comments. To reply to your earlier comment wrt the 'freezing' of sea water. Your reply was valid in that sea water freezes at a lower temperature than pure water. However, sea ice once formed is pure water so I should have worded my temperature reference around the 'melting' of sea ice as being a calibration point. Thanks for correcting me. For your second, "Your argument is predicated upon a false premise, Earth has a higher albedo than the moon." The Earth's surface albedo Interitus, without an atmosphere is that of the moon. It's the same rock. Go and check Trenburth's energy diagram for surface albedo. It shows that of the incoming flux transmitted by the atmosphere the surface spatially averaged absorbs 161Wm-2 and reflects 23Wm-2. The surface albedo with ice and deserts and foliage and ocean is therefore (23/(23+161))= 0.125 cf 0.12 for the moon. According to Kevin anyway. The increase in the Earth's albedo from without an atmosphere (0.12) to with an atmosphere (0.29) is due to the atmosphere. I'm simply pointing out that heralding a component like water for heating the surface as the major GHG component without realising that it already stops a very significant amount of energy from directly heating the surface is unfairly biased.

knocker. Even if I give you a 'golden opportunity' to calculate the Earth's theoretical temperature without an atmosphere and return reporting my post contained an error, you fail to take advantage! NASA's black body temperature is correct! I conclude that you do not know how to easily calculate this figure(?). The Earth's temperature without an atmosphere calculated from lunar albedo (0.12) and emissivity of lunar rock (0.96) is 273K (grey body effective temperature). Not 271K. So, the total surface enhancement, irrespective of process, due to having this atmosphere on Earth is limited to within 15K (288-273). Not 33K as is popularly believed! That's 55% of the 'effect' vanished into thin air! You're very quiet, are you ok?

4wd. I find it strange that more often than not hemispheres are treated separately. Granted they differ due to topology but sometimes we have a parallel experiment. When polar jet streams become meridional from zonal in both hemispheres and one has less ice and the other more, we have to be careful about blaming it upon sea ice, for example. I find it very difficult on either post to not encompass both in my reasoning. What do you think?

knocker, see what I am doing. I am pulling the foundations of you fiction out from under your feet. I'm pulling effortlessly 50% of the 'greenhouse effect' from under your feet. Once you are founded on fiction buddy, you are unfounded. Fact. I haven't even started on Trenburth's fiction yet. Awaiting your reply.

By the way. People believe, do they not that the effect of 'greenhouse gases' enhances the surface temperature by 33K. Now I am stating that the total effect of having an atmosphere is no more than 17K. Fact. Show that I am incorrect.

I'll disassemble Trenburth's energy budget and disclose all of your unfounded 'faith' in this man's 'adopted' science. All you have to do is find fault in my reasoning. Awaiting your reply, knocker.

knocker, go wave this in front of a physics professor. See if he disagrees.

Even NASA, get this one wrong, the moon's grey body temperature is 271K. NASA label it as the moon's 'black body temperature!!!! The calculation involves the moon's true emissivity of 0.95, so it's not a a black body! Laughable! But sickening. If we then acknowledge that the Earth's surface temperature is 288K. Then if I am correct then the total atmospheric thermal enhancement is 17K. If NASA is correct the enhancement is less, because the moon isn't a black body.

BFTV. Are we talking extent or volume?

knocker, "Posted 09 September 2014 - 11:42 In view of some very recent 'scientific revelations' in the arctic thread I thought it about time to come back to earth, so to speak. So regarding global energy budgets an excellent start is an article by Kevin Trenberth and the paper he refers to in it. Easy subject it is not." Care to take up the discussion again then, on this thread?

mullender83, Phenomenal. Look forward to seeing this on the news tonight! Do you not feel that the media and scientific opinion and consensus are going to be proven wrong in due course?

mullender83, hopefully Antarctic sea ice won't go up any higher. The heat capacity and thermal lag of the Southern Hemisphere makes Antarctic sea ice a long term integrator of thermal change. Obviously the heat entering the oceans and the illusion of back radiative forcing are insufficient to stop the sea freezing when it should (according to mainstream climate science) just melt away. Maybe something more obvious, like changes in the energy supply, the old bright thing up above that climate science forgot. Perhaps. Hey, is mentioning the current and prolonged solar downturn off topic here?

Stewfox, I think you are seeing through some of the wool being pulled. If it's warmer ice melts if it's cooler water, either fresh or salt, freezes. Well spotted that less ice forms near the melting area. Ice makes a great integrator of flux, unlike temperature which is a non linear and already averaged function, the average of which is dependent upon the weighting algorithm.

stewfox, "I hope so because you have already been told and you seem to encourage confrontation This thread has been without it for the last 3/4 years." Sorry that you feel that way stew'. Sometimes I can't help coming back with a little humour and bending the rules a little. It's a weakness! It was never my intention to offend. We are all adults, I assume, and capable of defending our opinions. I am quite sensitive to arguments that individuals cannot substantiate from basics. If I sense that then I will make comment. I react to others and treat them largely as they treat me. I have followed sea ice and climate on a daily basis for years studying both the data and the science. My apologies, although I'm not really bothered if reef deletes the comment you highlighted, so I haven't apologised to you in order to save it.

oldsnowywizard, thanks for the reply. Yes DMI is showing rapid, systematic decline and as you report, without the often massive spiking up we often see. The drivers that produce these spikes are the key to understanding the winter high temp anomalies. They are likely to be due to circulation patterns. It is interesting but obvious to note that if we believe that the climate can vary, then ocean heat content does not buffer this effect. Rather the effect drives the flux into or out of the ocean. May seem backward, but every temperature downturn is immediately preceded by warmth and vice versa. When warm ocean air meets cold we get heavy precipitation. The ocean heat has the ability to drive cubic km of water as snow onto the land. Greenland experienced 11Gt in 24hrs the day before yesterday! Open ocean can lose heat to space. Ice can cap those losses to a degree. Hence the tendency to cycle.

Ok. So I could be in trouble if I stick this in here! Cryosphere showing 'all time record high extent' for Antarctic sea ice! http://arctic.atmos.uiuc.edu/cryosphere/antarctic.sea.ice.interactive.html Guess that must be the warming effect of CO2?

Is observation of current levels of Antarctic sea ice considered off topic? Is consideration of global sea ice off topic?

Hi knocker. Thanks for the reply. You say, "I don't rule out natural variations and never have done but I don't know enough about 1850 and 1903 to give a detailed answer." Well you know the North West Passage was open those years because it was navigable. What would your 'gut instinct' tell you about Arctic conditions during and around those years, with knowledge that you believe rapid changes are 'unnatural'? You also say, " But regarding the Halocene as you no doubt already know the temperature construction is very complicated. It varies regionally, seasonally and from early, middle and late Halocene.as can be seen from the isotopic record from the GISP2 ice core. Impossible to cover this in a simple answer, and I wouldn't even attempt it" See my text processor (mind) is picking up a misspelling from this copy and paste! Construction is complicated? (It's not difficult to reconstruct a 'hockey stick'! ) Are you saying we don't know what climate was like during the Holocene, or that we do? If we don't then how do we know what is 'unprecedented'? "but basically we are talking orbital variations, insolation changes and the interaction with natural variations that aren't fully understood." Interaction with natural variations that aren't fully understood! Now we are on common ground buddy! Hence subtraction as a sum of an unknown quantity from a known quantity leads to an unknown answer. By your own powers of deduction, you have no idea of the potency of natural drivers. You also go on to say, "But as much as I consider natural variations I also rule in CO2 forcing as being the current main driver and the scientific case for this is compelling." Now, seeing as discussion of this is directly relevant to 'opinion' of Arctic sea ice but considered 'off topic' are you goading me to decimate the fabric of your 'faith'? If you don't want it here. Then where?

Hi knocker. "I would imagine that very unlikely. During the climatic optimum I would think levels could have been similar but I doubt the drop would have occurred within such a short time span." What about 1850 and 1903? The flux imbalance to do this is time averaged at 0.4Wm-2 according to PIOMAS. Considering climate science works upon 4Wm-2 flux imbalance producing a 1deg global response, nothing dramatic in terms of energy to melt ice has happened to the Arctic. Why would you think that nature couldn't do this? Just before the start of the Holocene the ice cores show the Younger Dryas period fluctuated by several degrees globally in less than ten years. Probably closer to five. Vostok ice core courtesy of BAS show 342 similar warming events averaging 0.75 degC/century, 42 of which had a higher trend of 1.3degC/ century.

Hi jonboy. I agree that this is the time we would expect minimum approximately, of late. DMI are showing air temperatures around the pole falling largely with the ERA40 trend line after another summer as cool as any in the time series. This and last summer could be the coolest consecutive pair. It appears that the mechanisms that transport energy to the winter pole are responsible for the time averaged air temperature anomaly. Anyway, it's averaging several degrees below North of the 80th parallel. Increase in extent won't be far away.

Does anyone here think we are about at this years minimum? Do we feel that the Arctic will lose anything significantly from here on? What are your views?

Gray-Wolf. "Until we regain the lost 70% of sea ice we will remain at the mercy of conflagrations of natural drivers that can , and will, leave the basin with less than one million sq km of ice before the 2030's." It's sweeping statements like these that ensure the 'deniosphere' isn't short of members. Resolving a superimposed and unproven trend from a natural cycle without thorough understanding of the strength and capability of the latter is an impossible calculation. Having supreme belief in the answer when it depends ultimately upon subtraction of an unknown, is 'faith', not science.

Hi knocker. Interesting videos. I'm not sure of the use of 'highly selective' as a description. Do you agree with the view that recent low ice levels are of an unprecedented nature? If so what do you make of the North West Passage being open in at least 1850 and 1903? Do you believe the NWP could be open and navigable with several metres of multi year ice covering the rest of the Arctic?

mullender83, thanks for the reply. Are you aware that the flux imbalance according to PIOMAS is 0.4Wm-2 to melt ice according to the 'linear trend'. This is swamped by the seasonal variation. The solar flux variation is catalogued at 0.1% or 1.36Wm-2 variable with the most variable part being extreme UV which is always thermalised peaking atmospheric total potential temperature at the stratopause. Some of this is fed continuously into the polar regions especially the winter vortex carrying the solar temperature signal. Also the sum of all mass impingement fed through the magnetic poles becomes thermal. Solar reduction will remove a few Watts per metre squared as real energy from this contribution. Is that so hard to believe? Total column ozone lags solar activity by quarter phase as maximum solar UVC produces maximum rate of ozone production, not maximum ozone. No eqm due to lag. All UVC and UVB as a variable becomes thermal due to entropy. There are no radiative consequences (losses) before thermalisation. Add to this changes in fundamental wind strengths and subsequent changes in decadal resultant ocean surface currents and your starting to appreciate what solar energy variation can do in small increments. Resultant feedback from ice albedo becomes potentially unstable. Watch what happens.