full_frontal_occlusion

Climate (like quantum mechanics) is a stochastic process, it cannot be understood purely in terms of patterns or attributing specific events to a definitive cause. But like quantum mechanics it can be made sense of on a probabalistic level. Everyone has an opinion on the subject and the problems occur when those opinions are shared as if they were definitive scientific authority. As well as the lay-person, those opinions also come from very highly respected individuals from Nobel-Prize winning physicists to senior politicians, QC's and other respected statesmen. But even these individuals are no more qualified to speak authoritively than Joe Bloggs on the matter. Media has earned itself a bad reputation for sensationalism and over-extrapolation. Together with the unstoppable deluge of conflicting information and mis-information it's easy to 'cherry-pick' articles to back up one's own personal viewpoint and completely trash everything else. Many take the view that the Earth's climate has always changed and that our very existence means we are not the cause of climate change and even if we were, the Earth will recover - eventually. There is one glaring fact overlooked: That never in all of biological history has 7 billion humans existed and whose entire future depends on the state of the Earth. We do not have a clear picture of what will happen tomorrow or in 30 years to the planets shifting climates. What we do know is that CO2 is inextricably linked with the Earths average global temperature and that continuing to strip the planet clean of it's non-renewable resources and unabated anthropogenic dumping of by products into the atmosphere and oceans is an uncontrolled experiment on a global scale. But increasing scientific literacy will not win over hardened sceptics even though the overwhelming majority of climate scientists agree on which direction global-warming is headed and why. I believe the world is divided into two climate change camps (believers and sceptics), each following the path not necessarily of true science, but governed by their own individual personality. Those of a hierarchical, individualitic world view are more likely to be sceptical, whilst those of a more egalitarian, communitarian worldview are more likely to side with the scientific majority. The old self interest vs altruistic individual divide. Increasing scientific literacy only hardens the divide. And therein is the issue, that whichever view one takes, the opposite camp is perceived as threatening their individual values and freedoms and no ammount of evidence will convince otherwise. Political policy fears drive each camps empirical viewpoint not the science. Action which is perceived to negatively affects those within the opposing camp will always be rejected. The more comfortable route for these people is to question the science and delay action. The argument will not be won at the scientific level. ffO.

Astonishing. The author makes a stupendous conclusion and utterly fails to quote neither source, derivation or proof. Thus his statement is an assumption at best leading on to further statements predicated on that assumption. This alone renders his whole paper rather worthless and would be utterly destroyed if presented at conference. ".......This, in its turn, will lead to the rise of Earth albedo, the drop of atmospheric concentration of the most important greenhouse gas – water vapor, as well as of carbon dioxide and other gases. Let us note that water vapor absorbs ~68% of the integral power of the intrinsic long-wave emission of the Earth, while carbon dioxide – only ~12%. As a consequence, a portion of solar radiation absorbed by the Earth will gradually go down together with manifestations of the greenhouse effect caused by the secondary feedback effects. The influence of the growing consecutive chain of such changes will cause additional decrease of the global temperature exceeding the effect of a bicentennial TSI decrease." ffO.

Models are purely mathematical, constructed to obey the laws of physics. However they are an approximation - albeit one which is continuosly improved. They are not perfect and do not contain every single physical-variable possible nor is their resolution capable of crunching to a scale below which error is eliminated. That feat is a very, very, long way into the future. As each computed time step is based on the output of the previous computation, the errors will accumulate getting larger at each successive step. Hence why FI is taken with a very large pinch of salt. The equations used are simultaneous and there are several solutions, hence the need for the ensembles which introduce a random 'seeding' in an attempt to understand the 'spread' of potential solutions which gives a reasonable indication that any given output has the highest probability of success. All this to say some runs will be more successful than others and hence the observation that sometimes the models 'go off on one'. Hope this goes some way to answering your question. ffO.

Way too marginal and too many variables for this mornings suggestion of snow on Friday. All of the following need to be in place fro that to happen: The track of the LP system today crossing north of Scotland and out into the North Atlantic, cyclogenesis out in the far Western Atlantic, secondary lows dragged around the main LP pulling in diluted PM -5 850hpa air on its flank as it passes through, dew points and wet bulb on the right side of 0C? The ensembles show this marginality very clearly with a large spike in distribution for both precipitation and pressure on Thursday night / Friday. Which is also why the % probability stays on the <50% region. If anything does come out of this, expect it to be sleety rain. ffO.

Just picked up on this thread. Fourier vs Wavelet? Perhaps the wavelet analysis produced results which were inconsistent with the conclusions the authors wished to present? i.e. wavelet analysis is likely to produce results potentially obscured by the Fourier analysis which woue make the task of explaining the results much harder. After all, Fourier is based on sine/cosine functions which correspond nicely with orbital periods. Wavelets have an infinite number of basis functions which could render the results difficult to justify without further analysis and justification through statistical significance. All in making the case for 'selective' data manipulation much easier to uphold. Cynicism in it's truest form. ffO.

You won't get a definitive answer - sorry. This site is populated by weather professionals, amatuers and lay public and the extremes of views are as evident here as anywhere else in the public domain. On the one hand you have those who are clear AGW is a clear signal above any natural forcing and have taken the view it is better to try something than nothing even if it is ultimately futile - though that is far from certain. On the other hand you have those who view any intervention as arrogance and the fallacy of AGW only serves to threaten their way of life. (Ironic that both sides see a threat?) Then there are those caught in the middle - waiting for more evidence before committing. But what will that evidence look like? Better computer models? Famine and death year upon year? Widespread and cyclical drought in temperate climates with crop failure etc? Then there is the politicisation of the issue and current global economics. Governments and individuals are only concerned with clear and present danger. Like Maslow's 'hierarchy of needs', AGW sits at the top of the social needs spectrum long after the basic survival needs of food, water, shelter, health etc. priorities. Sadly, this is an issue which will not be resolved now or even in the next several decades. It will be one for history to recall as either the greatest display of humankinds arrogance or the most outrageous example of ignorance. ffO.

True. In addition, the Coriolis component is proprtional to the latitude of the object. Not true. As the latitude of the object increases away from the equator then to conserve the angular momentum (omega) of that object, the spin rate must also increase. You have missed out the conservation of momentum laws: The angular momentum is the product of mass x spin_velocity x radius. If the radius of spin decreases then it's rate of spin increases. This is the crucial factor I think you are missing. Think of an ice skater and the conservation of momentum - the skater spins with arms outstretched (large radius), then pulls their arms inwards (decreases radius) and the spin rate increases substantially. Going back to our problem: as the object moves north it decrease its radius of spin closer to the spin pole. it's spin rate must also change to conserve momentum. hence the Coriolis force must also change accordingly. That also means the rate of change of Coriolis force is dependent on the rate of change of distance from the equator (velocity). ffO.

This gives just about the most complete explanation without resorting to the maths that I could find. http://www.dvandom.com/coriolis/index.html ffO.

Having read through my own answer, which helped me to crystalise why Bodhi is having difficulty understanding why the Coriolis force is always proportional to wind speed, I can simplify the whole process by stating: The Coriolis force is neither real nor can it give rise to a wind. Any mass of object, no matter how big or small or how fast it is moving, must by definition give rise to a proportional Coriolis component since the earth will move irrespective of those variables. That is to say a mass of 1gm needs a different compensation factor than one of say 100,000 tonnes. Both will appear to move in exactly the same way when the earth rotates underneath it. It matters not a jot how big or fast it is travelling. However the Coriolis force must therefore always be proportional to exactly compensate that mass. If we then consider that the inertia of an already moving object (in our case the wind speed of any given mass of air) is subject to exactly the same argument, it should now be crystal clear that the Coriolis force is indeed proportional to the wind speed. I really do hope this will help you and perhaps others who have struggled to grasp the concept. ffO.

Does the Chinese postion reported today lend any credance to the argument? Leaving the obvious distancing themselves from the Americans and the need to gain global approval as a leader taking its place on the world stage, does their stance signal a real concern? http://www.bbc.co.uk/news/science-environment-15444858 ffO.

Just noticed this still ongoing. Let's try a different tack? Please forgive me if I take this back to basics (I know you already understand, but it helps the thought process - and useful for others who do not) 1) Start with the givens: Our numerical weather problem, we need to determine the forces acting on a finite element of the atmosphere at any given point in time within a 3-dimensional co-ordinate system. (u,v,w). By determining the forces acting on the finite element of the atmosphere, we should be able to predict its future vector - i.e. velocity magnitude and direction and hence it's futire position. Our 3-dimensional co-oridnate system (frame of reference) is non-inertial. i.e. it is itself one that is undergoing acceleration due to the earths rotation. 2) Newtons laws of motion are defined with respect to a fixed reference frame. i.e. one that is not moving. 3) Newton describes acceleration as the rate of change of momentum or direction of an object w.r.t. that fixed reference frame. In other words, measurements made w.r.t. the earth. Big problem: Unfortunately, the earth is not a fixed reference frame as it is rotating. To successfully solve our weather problem, we must therefore include a description which defines that reference frame acceleration (elminate the error) or....... We must measure the effect of the earths rotation on that element of the atmosphere and describe the error arising as an apparent (imaginary) force exactly compensating for that error. That compensation is described as the Coriolis force. 6) The velocity vector component arising from the Coriolis force at any temporal point within the 3-dimensional co-ordinate system must now be defined: 7) So, referring to that finite element of the atmosphere: The inertia of any element is directly related to its velocity. i.e. a larger force is required to change its velocity or direction of travel as its velcity increases. If we measure its velocity vector relative to our co-ordinate system to be zero, then by association, the Coriolis effect at that point must also be zero. i.e. there is no relative motion. As the elements velocity vector increases, then its inertia also increases and the Coriolis compensation also needs to increase accordingly to null the earths rotation effect. The Coriolis compensation increases with increasing latitude. i.e. zero at the equator and maximum at the poles. In other words, the Coriolis compensation force that must be applied to correctly define the earths rotation and all other real forces acting on that element is directly proportional to that finite elements velocity vector which is itself defined by: a.) The pressure gradient (independent of the earths rotation) b.) Frictional force (independenat of the earths rotation) c.) Gravity. (independent of the earths rotation) d.) Latitude NB The Coriolis effect cannot generate a wind, it can only change its direction. By extrapolation, the Coriolis force is therefore always proportional to wind speed and with a latitude component defined by: F coriolis = 146x10 -6 v.sin(latitude) Where v is the wind velocity (m/s) and the constant 146x10 -6 as defined by the rotation rate of the earth. As such, the rotation of the earth is only in one direction and hence the Coriolis force always acts perpendicular to the direction of motion of the earth. The force acts to the right when looking north in the northern hemisphere which describes the motion of the atmsophere as veering to the left (equal and opposite according to Newton). I hope this aids your understanding. I don't believe I have made any mistakes. Try not to get bogged down by the full mathematical description, they are not intuitive in this process. Try to envisage what's happening physically first and then relate that to the full mathematical description. Best wishes. ffO.

Topical to say the least: http://www.bbc.co.uk...onment-15373071 In short, an independent science team (Berkeley Earth Project http://berkeleyearth.org/) comprising Nobel Prize Winners and other luminaries, and funded from sources that include organisations backing lobyists against action on climate change conclude: the new results agreed so closely with the warming values published previously by other teams in the US (NASA and NOAA) and the UK (CRU and UEA), " said Professor Muller. confirms that previously discredited studies (UEA) were executed carefully and that potential biases identified by climate change sceptics did not affect their conclusions. Since the 1950s, the average temperature over land has increased by 1C that the urban heat island effect is real but is NOT behind the warming registered by the majority of weather stations around the world. And critically: the emphasis that anthropogenic global warming (AGW) driven by greenhouse gas emissions is very much in their picture. They do state however that the team have not carried out any studies to determine the extent of human influence on the temperature increase. The last point I believe is the game changer for the majority of the public and yet the answers are not there. Full summary of the conclusions here: http://berkeleyearth..._Summary_20_Oct ffO

I'm not one for conspiracy theory (with which dissenters of AGW have had a day trip to the seaside, got drunk on the train and won the top prize in the tombola) but........there is a school of thought which wonders whether the big-boys realised a long long while ago that consumerism is unsustainable and that change is inevitable if the trend continued. A realisation that perhaps Marxist theories are bearing fruit? In order to sustain consumerism two possibilities emerge. Either: Continue expansion unabated - (Far East, South America, Asia, Africa) and let the developed worlds market take care of itself Engineer a controlled widespread cull of population by natural disaster and the spread of war in order to create re-generation demand and provide new room for expansion. Is not the latter that which started during the great wars of the 20th Century? The problem now as was not then is the possession of nuclear weapons. Wars therefore can only be fought in a conventional sense with those countries who do not have access. The hypothesis is given credance when one realises that none of the nuclear capable states are in direct conflict with each other but that wars are now fought either by proxy or with those who have mineral wealth ripe for exploitation. Just a thought. ffO.

If it's not an impertinent question, then what would it take for the majority of people to be convinced that the warming trend is exacerbated by Human influence or that in the next few years we are in danger of exceding a tipping point? Because if the science is not convincing enough now, then will it ever be or will people still say it's inevitable there is nothing that can be done? Does global panic need to set in and what would cause that panic for the developed and industralised populations to take heed if it's not already too late? ffO.

You are referring to one small countries experience over a very short time span and extrapolating that to what's happening on a global scale. 2010 tied with 2005 (within 0.01C) as the two warmest years on record despite the coldest winter in the UK for the last 30 odd years. Faith should not come into the equation else statements become opinions. The corollary to your statement would be that, sometimes you have to take the scientific 'proof' rather than rely on the 'leap of faith'. Science aside, both statements disturbingly appear to carry the same weight of argument at face value. However, one is based on limited experiences and the other looks for more than annecdotal evidence. ffO. ffO.

Everyone is of course entitled to an opinion however this is exactly an example of statements I referred to as both 'cherry picking' and descendancy into slander through inflammatory comment in post #5. The Hanson graph you posted was produced in 1988 nearly 24 years ago. The evidence and projections have moved on greatly since then. This is dissinformation and greatly confuses a general public trying to follow 'good science' and logical reasoning. ffO.

Apologies. it means: "After this therefore because of this" i.e. arriving at a conclusion based solely on the sequence of events. For example, the fallacy is evident in the statement: 'because we had two or three cold winters then global warming must be proven false. Logically the statement may be true however, in scientific rigour, two or three winters evidence is not of any statistical significance whatsoever as it cannot rule out underlying trends nor does it offer any hint at other variables which may cause the same effect. This must not be confused with science falling into the same trap. GW evidence is not accrued from a single source or event but from a huge array of diverse sources over a significant timespan. ffO.

There you hit the nail squarely: that the politicisation and commercialisation of the science has blurred the boundary between truth and fiction. The key issue though is that the stakes for getting it incorrect could be catastrophic. The powerful tactic used by both the political/commercial factions is to globally associate the poor and bad work as indicative of the the unreliable credibility of the genuinely good work and hence the entire scientific community is brought into disrepute. But of course the argument works both ways - that either side, pro or anti, can and does slander each other. That does not help the science and neither does it help the general public who will side with caution or any excuse to carty on regardless since the options are only do nothing or do something and get finacially hammered. In the end it's heads-you-win, tails-I-lose. For sure the science can be better - much better but that delay may carry a very high price as the stakes could not be higher. I would rather err on the side of caution: control the emissions and continue improving the science as fast as we can. Humans seem quite happy to wage war and handsomely compensate those responsible for the most suffering in the process. Doing nothing in the final 'hope' that Humans didn't have an option in the first place seems to me like a complete shirk of responsibility. ffO.

The whole scientific AGW issue does not and never has claimed Humans are more powerful than nature. It simply states that there are variations in global climate patterns that cannot be attributed to natural variation and cycles on its own. It also states that Human production of the so called Greenhouse-Gases is overwhelmingly the most likely cause. The wording however is precisely why sceptics will never be convinced: all science is based on the premise of theory, evidence and experiment and any theory only holds as long as evidence is not found to negate it. That does not mean all scientific theories are wrong - quite the contrary as new theories merely better-fit the evidence in a wider range of scenario. If you are going to assert yourself then to avoid a decendance into ad-hominem statement, please provide evidence for your assertion. It should be factual based on empirical evidence, independently verifiable and capable of withstanding serious peer-review challenge. Anecdotal evidence, hearsay, cherry-picking, inductive-reasoning and post hoc ergo proctor hoc assertions can be easily demolished as fallacious arguments. ffO.

It's because the Coriolis force is an apparent force and not a real force. That is to say the Coriolis force does not arise from any physical interaction but rather from the acceleration of the reference frame (the earths rotation) itself. Think of what happens in the Foucault pendulum example where a body of large mass and hence inertia is set in motion. Newton says the body will keep swinging back and forth in a straight line as there are no other forces other than gravity (for all intents and purposes) acting on it. But the earth is rotating underneath it. The pendulum stays constant but because the earth rotates so the pendulum rotates slowly in relation to the ground underneath and appears to be acted upon by an external force. IT IS NOT. The reference frame for the pendulum (i.e. the earth has moved) not the back and forth alignment of the pendulum itself. But in order to describe the effect mathematically, the rotation is attributed to an imaginary or apparent force that would have the same effect. Because of the earths rotation and hence the differing velocity as one moves toward the poles, the air mass will rotate. Within that mass there will be a real air pressure gradient which is a very real force. It's now easy to see that the pressure gradient (real) force is added to the corriolis apparent force, the apparent vector sum will always thus be proportional to the wind speed. Try this explanation with diagrams if it helps: http://www.aos.wisc....os101/wk11.html ffO.

The senstaionalised media-hype system is set up like dominoes: one tip-off and the whole set topples in line. The WMO ENSO status update at the begining of September http://www.wmo.int/p...ate_latest.html stated that last winters La Nina conditions had dissipated by May 2011 with a return to a more neutral ENSO state with pockets of La Nina persistence particuarly wrt to atmospheric conditions. In recent weeks however, the indications are favoured for either continued neutral ENSO or a return to a weak La Nina state. This conclusion seems is borne out by slightly below average SST's and at deeper levels around the eastern-central tropical pacific region. That was at the end of August/early September. Since then the Australian BoM prduced a summary http://www.bom.gov.au/climate/enso/ stating that the cooling trend has continued consistent with a return to La Nina conditions and backed up by atmospheric indicators with the SOI reaching +8 (threshold for La Nina). Consensus is that if La Nina does form, then it will be weaker than the last event. All this to say the probability of a colder winter for the UK is present if La Nina develops. The critical factor is that a colder winter is not guaranteed, just that the probability ofr one is raised somewhat and even this is a grossly over simplified assumption as La Nina is not the only influence on a cold UK winter by far. Once bitten, twice shy the UK authorities will not want to be caught with pants down again and hence the directives to 'be prepared'. Taking that into context with todays report on solar UV fluctuations (NASA SORCE mission) pointing to a connection between that and global weather patterns and the mention of the Maunder Minimimum is enough for the media sniffs to put 2+2 together and get eleventy twelve. The sensationalism kicks into overdrive because as some one earlier said: warm winters do not sell copy. ffO.

A minor point and not meant to be pedantic: Alan is correct in saying mathematicians use the symbol i to denote the square root of a -ve number. Engineers use the symbol j when writing equations in order to avoid confusion with the symbol for current which is also i and, is itself used (not A for Amperes which would otherwise be logical) since mathematicians use A to denote arbitrary variables. But I digress. Regarding the observation of 'weighing' less than nothing? Terminology is critical here: Weight is simply the acceleration force a body feels due the the exertion of gravity. It is utterly different to the Mass of an object which is the amount of physical matter in that object. Mass and gravity are however the components from which weight is calculated. -ve mass? We should start with an explanation of how imaginary numbers give rise to real-world solutions and applications: Electrical/electronic engineering in particular would be impossible without recourse to imaginary numbers (square roots of -ve numbers) and in that context is simply a way of demarking the physical domains between the electric and magnetic fields which are themselves inseperable. The manifestation of the equations using complex numbers (i.e. numbers which have both a real and imaginary part) is evident in the technology which pervades everyday life and is the probably the most relevant example of how seemingly arbitrary (and bizarre) mathematic concepts work in the real world. Complex numbers give rise to real-world soultions in many ways: j = sqr root (-1) = (-1)0.5: an imaginary number; j2 = j x j = (-1)0.5 x (-1)0.5 = -1 ; a real number; j3 = j x j x j = j x j2 = -(j) : an imaginary number; j4 = j2 x j2 = -1 x -1 = 1 : a real number. Equations of the form (a + b ) x (a - b ) litter engineering. When b is replaced with an imaginary number i.e. (a+jb)(a-jb) the equation is known as a complex conjugate and always gives rise to real answers. (a+jb)(a-jb) = a2-ajb +ajb - j2b2 = a2+b2 There are many other examples. So what is mass? Einsteins eqautions point to the source of gravitational fields. Which is simpy a way of saying the force experienced by a particle constrained to follow the curvature of space-time when near the presence of another particle or object. In Quantum Electro Dymamic theory, sub-atomic particles all have anti-particles: the electron has the anti-electron or positron; neutrino's have anti-neutrino's etc. These are not imaginary particles but very real. However they exist for such short times and decay rapidly to the longer lived particles of which our everyday universe is made. Incedentally, anti-matter is produced and captured in the experiments at CERN and can be held in stasis for the current record of 16 minutes. Magnetic fields both exhibit repulsive and attractive forces. I know one cannot say in the quantum world that because of event a it follows that event b is certain - that is disproved many times over. I therefore cannot be assume that -ve mass or energy is an impossibility and neither can one say it is a given awaiting to be proven. Indeed the difficulty with combining quantum theory with Einsteins theories is that they both give rise to either infinities or singularities and mathematicians hate both. They create boundaries which cannot be crossed in the convetional sense. i.e. black-holes or spontaneous existences etc. Particle and astro physicists look ever more closely and closer to those events in order to gain clues which may point them towards an answer. I am not worthy to breath their names let alone postulate with any authority on whether Einsteins equations point to a reality or even a solution. It does seem to me though, that no doors should be closed in that search. And of course I find it great fun to try. ffO.

I concur with your final equation v=(c2 - (m2c6E-2))0.5 When m=0 the equation reduces to v=(c2)0.5 or v=c. However, the roots are complex for values of m2C6/E2>c2 or v>c. i.e. -ve mass or -ve energy are the only real solutions. Which seems to imply that objects with -ve mass (if such a thing exists or is even postulated) would travel very much faster than light. Is this where the concepts for Warp-Drives came from? An anti-Higgs Boson would look very enticing indeed. Either way, the experiments at CERN and the LHC will open up a new chapter for the annals of physics. ffO.

You are of course correct, it is a loaded question as it omits the independent reference frames (vectors) and as such, my statement trivialises the original somewhat. Einstein used Maxwells theories as a basis to explore the apparent lack of evidence of the so called 'luminiforius ether' as result of the Michelson-Morley experiment. Maxwell used 2nd rank (anti-symmetric Euclidean space) tensor fields to combine the previously independent electric and magnetic fields to derive the electromagnetic unified theory. Einstein applied Lorentz transformations to explore what would happen to those results when comparing independent reference frames moving wrt to each other. In a futher paper he applied Reimman curvature tensors to explore the effects of gravity and thus derived his theory for General Relativity. So in my example E is of course the relativistic energy of particles belonging to independent reference frames, themselves moving wrt to each other (which are ommited). The rewritten formula is therefore far more general than the original. I'm glad someone stayed awake! lol. ffO.

Almost right: Einsteins equation E=mc^2 is an abridged version of the original which is: E=mc^2/sqrt(1-v^2/c^2) Rearranging the equation gives: v=c/E*sqrt(E^2-m2*c^4) Now set the mass to 0 and the two Energy terms will cancel and we are left with v=c/(1-0) which is just v=c. In other words the equation tells us that a massless particle cannot travel LESS than the speed of light (nor for particles with -ve mass but that is another issue! Higgs Boson anyone? lol). ffO.