Meteoclima

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Marotzke & Forster Revisited

Marotzke & Forster(2015) found that 60 year trends in global surface temperatures are dominated by underlying climate physics. However, the  data show that climate models overestimate such 60 year decadel trends after 1940.

The recent paper in Nature by Jochem Marotzke & Piers Forster ‘Forcing, feedback and internal variability in global temperature trends’ has gained much attention because it makes the claim that climate models are just fine and do not overstimate warming despite the observed 17 year hiatus since 1998. They attempt to show this by demonstrating that 15y trends in the Hadcrut4 data can be expected in CMIP5 models through quasi random internal variability, whereas any 60y trends are deterministic (anthropogenic). They identify ‘deterministic’ and ‘internal variability’ in the models through a multi-regression analysis with their known forcings as input.

\Delta{T} = \frac{\Delta{F}}{(\alpha + \kappa)} + \epsilon

where \Delta{F} is the forcing, \alpha is a climate feedback and \kappa is fraction of ocean heat uptake and \epsilon is random variation.

This procedure was criticised by Nic Lewis and generated an endless discussion on Climate Audit and Climate-Lab  about whether this procedure made statistical sense. However for the most part I think this is irrelevant as it is an analysis of the difference between models and not observational data.

Firstly the assumption that all internal variability is quasi-random is likely wrong. In fact there is clear evidence of a 60y oscillation in the GMST data probably related to the AMO/PDO – see realclimate. In this sense all models are likely wrong because they fail to include this non-random variation. Secondly as I will show below the observed 15y trends in Hadcrut4 are themselves not quasi-random. Thirdly I demonstrate that the observed 60y trends after 1945 are poorly described by the models and that by 1954 essentially all of the models predict higher trends than those observed. This means that the ‘deterministic’ component of all CMIP5 models do indeed overestimate  the GMST response from increasing greenhouse gas concentrations.

Evidence of regular climate oscillations

Hadcrut4 anomaly data compared to a fit with a 60y oscillation and an underlying logarithmic anthropogenic term.

Hadcrut4 anomaly data compared to a fit with a 60y oscillation and an underlying logarithmic anthropogenic term.

Figure 1 shows that the surface data can be well described by a formula (described here) that includes both an net CO2 forcing term and a 60y oscillation as follows:

DT(t) = -0.3 + 2.5\ln{\frac{CO2(t)}{290.0}} + 0.14\sin(0.105(t-1860))-0.003 \sin(0.57(t-1867))-0.02\sin(0.68(t-1879))

The physical justification for such a 0.2C oscillation is the observed PDO/AMO which just like ENSO can effect global surface temperatures, but over a longer period. No models currently include any such  regular natural oscillations. Instead the albedo effect of aerosols and volcanoes have been tuned to agree with past GMST and follow its undulations. Many others have noted this oscillation in GMST, and even Michael Mann is now proposing that a downturn in the PDO/AMO is responsible for  the hiatus.

15y and 60y trends in observations and models

I have repeated the analysis described in M&F. I use linear regression fits over periods of 15y and 60y to the Hadcrut4 data and also to the fitted equation described above. In addition I have downloaded  42 CMIP5 model simulations of monthly surface temperature data from 1860 to 2014, calculated the monthly anomalies and then averaged them over each year. Then for each CMIP5 simulation  I calculated the 15y and 60y trends for increasing start year as described in M&F.

Figure 2 shows the calculated  15y trends in the H4 dataset compared to trends from the fit. For comparison we first show Fig 2a taken from  M&F below.

READ THE REST LINK PHYSICST CLIVE BEST>>>>Marotzke & Forster Revisited

IPCC Scientist’s dilemma

Posted on March 3, 2015 by Clive Best

The headlines used by most politicians and green pressure groups are based on the IPCC attribution of the human impact on the climate. Climate change policy and political soundbites can usually be traced back to the ‘Attribution statements’ contained in each of the 4 yearly asessment reports. The political pressure on scientists to forever increase their “certainty” about  man-made global warming is intense. The stumbling block is that the pause in warming since 1998 is getting harder to explain away and  is beginning to undermine this process. The more scientists try to explain the pause the more difficulties they find themselves getting into . The latest to make this mistake is Michael Mann who can now ‘explain’ the pause as being due to a natural cooling trend of the AMO/PDO since 2000, thereby masking underlying anthropogenic warming.

Mann’s identification of a natural oscillation component in global temperature data. NMO is a net combination of AMO and PDO. Note the amplitude of the oscillation is 0.4C

Mann is quite right that the PDO/AMO may likely be the cause of the hiatus, but by accepting this possibility he unfortunately  drives a coach and horses through the AR5 attribution analysis described in chapter 10. This is because the probability analysis used there depends on natural variability being precisely zero since 1951.

First let’s look at the ever growing IPCC certainty about AGW since the first assesment in 1990

  • 1990 AR1: ‘The unequivocal detection of the enhanced greenhouse effect from observations is not likely for a decade or more. ‘
  • 1995 AR2: “The balance of evidence suggests a discernable human influence on global climate”
  • 2001 AR3: “most of the observed warming over the last 50 years is likely to have been due to the increase in greenhouse gas concentrations.”
  • 2007 AR4: “Most of the observed increase in global average temperatures since the mid-20th century is very likely due to the observed increase in anthropogenic greenhouse gas concentrations”
  • 2013 AR5: “It is extremely likely that human activities caused more than half of the observed increase in GMST from 1951 to 2010. The best estimate of the human-induced contribution to warming is similar to the observed warming over this period.”However is this increased confidence actually justified in view of the fact there has been essentially no surface warming at all  since 1998?  The AR5 attribution analysis is all based on figure 10.5 shown below and the seemingly small error bar on the Anthropogenic component ANT. Despite the much higher uncertainty in the two individual anthropogenic components GHG and aerosols, the ‘fingerprinting’ analysis can supposedly isolate ANT with a high degree of certainty. This fingerpriniting is extremely obscure and is not at all well explained in the text of chapter 10. Even Science of Doom is not convinced by their arguments. However let’s be generous and assume that they are correct and the error on ANT can  indeed be shown to be that small. The real problem they now have is that the probability that ANT and Observed agree depends on the assumption that Internal Variability is 0.0 ± 0.1 C – but we just saw that this is now increasingly unlikely.
  • So 23 years of intense research has supposedly increased scientific consensus from an agnostic position (AR1), a discernable signal (AR2), through likely (66%-90%)  in AR3, to very likely (90-99%) in AR4, and finally to extremely likely (>99% certain) in AR5. This ratcheting up in scientific certainty, egged on by various pressure groups has underpinned the  increasing political pressure on worldwide governments to abandon fossil fuels. Taking a step backwards now is unthinkable.>>>>>>>READ THE REST LINK PHISICS Dr. Clive Best

  • La ricerca scientifica sul Tides e le conseguenze sul Jet Stream e gli indici tele connettivi.

     

    La ricerca scientifica sulla forza gravitazionale/mareale (Tides) con effetto combinato della Luna e il Sole sulla massa d’aria imponente circumpolare del Jet Stream (flusso troposferico) è sempre più presa in seria considerazione all’estero, con il contributo prestigioso internazionale dal punto di vista scientifico del fisico e climatologo inglese mondiale Dr. Clive Best.

    Una collaborazione prestigiosa e importantissima, che ha aperto da quasi un anno i confini internazionali a questa nostra ricerca scientifica sul Tides e gli effetti conseguenti sulla corrente a getto circumpolare della libera atmosfera.

     Max Tides del 3 Feb che disporrà un JS favorevole a neve anche in pianura 3/4>6 febbraio

     

    La ricerca scientifica sulle variazioni del Tides (forza mareale) generata dalla forza gravitazionale risultante Luna>Sole>Terra, viaggia spedita e si sta ulteriormente approfondendo all’estero, dove, quanto prima, uscirà un articolo scientifico in inglese specifico, che sarà pubblicato a livello mondiale.

    Un imponente fiume d’aria come il flusso troposferico, presente circumpolare a quote medie da 5 a 12 km e con una massa di notevole spessore, non sfugge certo alla legge di gravitazione universale di Newton, e il Tides si conferma la causa principe di ogni modifica di velocità e di direzione del jet Stream nella libera atmosfera.

     Central England Temperature Anomalies "Physicst Dr. Clive Best"

    Posted on January 4, 2015 by Clive Best

    The Met Office reports  that 2014 was the warmest year in the 354 year series of temperature measurements in central england. Ed Hawkins also has a post on this.

    So is it true and what does it really mean?

    annual mean temperatures since 1990 to 2014. The red line is a long term trend fit described below.

    Well 2014 does indeed scrape through  above 2006 as the warmest year, but the quoted measurement error is 0.1C.  So statistically it would be more correct  to say that it is  60% probable that 2014 broke the record. However in this post I want to understand better the full time series and identify a  long term warming trend in CET.

    This gives a rather different narrative than the simplistic one of just CO2 induced warming of the UK climate.

     

    The data shows that there has definitely been a slow but continuous warming trend since 1660 until the present time staring well before the industrial revolution. Furthermore there is no obvious evidence of any CO2 induced acceleration in warming as emissions increased post 195o.

    So let’s do something a little different and calculate temperature anomalies relative to that long term trend instead of relative to 1961-1990. The result of this procedure is shown below

     

    Relative to the 350 year long term trend there is no real evidence for any recent anthropogenic warming. Now let’s simply put a spline through the anomaly data to see if there are  shorter time scale trends.>>>>>>>

    READ THE REST>>>>link >>Clive Best

     

     

    AR5 Attribution Studies

     

    Just how reliable is the IPCC AR5 advice to policy makers?

    The recent IPCC report stated that climate scientists are 95-100% certain that the observed temperature rise since 1850 is anthropogenic. The headline attribution statement in Chapter 10 was

    “It is extremely likely that human activities caused more than half of the observed increase in GMST from 1951 to 2010.The best estimate of the human-induced contribution to warming is similar to the observed warming over this period.”

    World political leaders are basing policy on the validity of this statement, which is entirely based on comparing CMIP5 models to global surface temperature data. These ‘fingerprinting’ studies are described in chapter 10, which I find all but impossible to comprehend. The underlying assumption in AR5  is that natural climate variability has essentially played no role in warming since 1950. However is this actually true ?

    Figure 1 shows a comparison between the ensemble of CMIP5 models and observations.

    Agreement until 2000 would appear to be reasonably good. However we then read in Chapter 9 Box 9.1 that in reality:

    Model tuning aims to match observed climate system behaviour and so is connected to judgements as to what constitutes a skilful representation of the Earth’s climate. For instance, maintaining the global mean top of the atmosphere (TOA) energy balance in a simulation of pre-industrial climate is essential to prevent the climate system from drifting to an unrealistic state. The models used in this report almost universally contain adjustments to parameters in their treatment of clouds to fulfil this important constraint of the climate system.

    So the models are tuned so as to describe past observations. Furthermore periods of cooling are explained by volcanoes which are simulated by something called ‘EMICS’ – Earth System Models of Intermediate Complexity up until 2005. Please don’t ask me what EMICS are but there is also no doubt in my mind that these are also tuned so that  aerosols can then match the global temperature response to volcanic erruptions such as  Pinatubu!

    Science of Doom has written a detailed analysis of AR5 attribution studies and even he is not convinced.  He writes:

     

    Chapter 10 of the IPCC report fails to highlight the important assumptions in the attribution studies. Chapter 9 of the IPCC report has a section on centennial/millennial natural variability with a “high confidence” conclusion that comes with little evidence and appears to be based on a cursory comparison of the spectral results of the last 1,000 years proxy results with the CMIP5 modeling studies.

     

    He proposes an alternative summary for Chapter 10 of AR5:>>>>>>>

    READ THE REST>>LINK PHYSICS Dr.CLIVE BEST

     

    Arrivo della neve a quote molto basse come in pianura dal 26 e 29 dic e sensibile flessione termica.

     

    L’inverno è entrato ufficialmente dal punto di vista astronomico dal 22 Dicembre ma con una situazione atmosferica indubbiamente mite in quota caratterizzata da minime basse giusto per inversioni termiche o massime basse per nebbie persitenti nei fondi valle e pianure interne.

    Una situazione termica temperata e gradevole per una stagione invernale meteorologica e climatica che stava dando l’illusione di un Inverno che si sarebbe protratto non all’altezza del periodo sia in questo fine 2014 come anche per il 2015.

    Oramai in rete come nei notiziari televisivi, eravamo bombardati da informazioni climatiche inerenti a temperature fra le più calde del secolo  (come sempre catastrofismo puro e gratuito) con profezie di un inverno 2014-15 destinato a soccombere ad una persistenza di aria mite sopramedia con neve destinata a rimanere assente ovunque come sui rilievi, con un periodo Natalizio ipotizzato tutto “in camicia”.

    Martedì, 23 Dicembre 2014 00:00

    CO2 Thermagedon ?

    Scritto da

    CO2 Thermagedon ? Dr.Clive Best

    Posted on December 21, 2014 by Clive Best link>http://clivebest.com/blog/?p=6337

    What is the worst damage that increased Carbon Dioxide could possibly cause on earth?The  answer is  surprisingly little  (ignoring hypothetical ‘feedbacks’) !

    So now let’s imagine the most extreme case possible. What   if CO2 levels were somehow to rise 300 times higher than current levels reaching crazy levels like 1%? Just how hot would the earth then get ?

    So really not so bad after all! The maximum possible CO2 greenhouse effect on earth is about 13 deg. C.

    These calculations are based on a line by line ‘radiative transfer’ code covering the  dominant 15 micron absorption band described here.

    So what is the problem of anthropogenic global warming – if any?

    Image 1*

    For 99.9% of earth’s 4 billion year climate history CO2  never has been a problem. On the contrary CO2 has helped to keep the earth’s temperature just right for life to flourish. In reality CO2 is a wonderful stabilising feedback that counteracts  external  ‘dangerous’ forcings on climate, and will continue to do so as long as life continues to flourish.

    CO2 levels in the earth’s atmosphere normally react to changes in climate. They naturally regulate atmospheric CO2 by  responding to changes in ocean temperature. It is basically only now  that CO2 levels have increased before temperature, with the possible exception of the Paleocene–Eocene Thermal Maximum (PETM) event 50 million years ago. Anthropogenic CO2 ‘climate change’ is less than a blink in the eye.

    Geological  evidence shows that during the PETM, CO2 levels rose by about 3 times more than the most pessimistic levels imaginable today, even  if humans were to burn all available fossil fuels on earth. Yet during PETM  temperatures only rose by just 5C. Furthermore it is entirely possible that the PETM excursion in CO2 levels was not due to some volcanic belch of CO2,  but instead was indeed the result of some external astronomical forcing such as a supernova, which CO2 levels then reacted to as a response.

    So we need to keep things in perspective regarding (catastrophic) anthropogenic climate change. Yes human activity will most likely result in some small warming but its effect will naturally be  rather limited.

    It may even turn out to be a blessing in disguise because increased CO2 levels now may likely delay the onset of the next ice age which otherwise is due to start around now. Another ice age would be orders of magnitude more catastrophic.

    Dr.Clive Best                                                                                           Image 2*

    http://clivebest.com/blog/

    Image 1*

    CO2 greenhouse effect for concentrations up to 0.1 C. Shown are the direct surface temperature responses under ‘business as usual’ policies  untileventually  fossil fuels are exhauted.

    Image 2*

    Saturation of the narrow CO2 15 micron lines into the Stratosphere ensures that total greenhouse warming is limited to 13C.

     

     

    In arrivo il grande freddo dopo la parentesi Africana sciroccale con differenze di 15° negativi.

     

    La situazione fisico/matematica attuale (ultimo weekend di Novembre) vede la presenza di componente del Jet Stream in affondo sul mediterraneo centro-occidentale, con conseguente richiamo sciroccale molto mite in area Italiana.

    Una costante ripetuta in questo piovosissimo e mite autunno 2014 che ha generato anche forti piogge e notevoli danni alluvionali, come sempre esaltate da dissesti idrogeologici, per l’incuria dell’essere umano, ed esaltate da  selvagge urbanizzazioni eseguite senza il minimo rispetto del microclima.

    L’analisi e la riflessione sul Jet Stream convalida una componente troposferica (JS) invadente e perseverante verso le basse latitudini a livello mondiale, che ha caratterizzato  costanti affondi di Aria fredda in Europa verso il continente nordAfricano.

    Domenica, 16 Novembre 2014 00:00

    Tides and the Jan 5th storm 2014

    Scritto da

    Tides and the Jan 5th storm 2014

     

     

    In this post I look at how exceptionally strong tides over the first few days of January 2014 could have played a role in the severe storm that hit the UK on the 5-6 January.

     

    Meteociel.fr provide twice daily (midnight and midday) pressure maps of the polar regions which show how the polar Jet Stream changes rather well. The Atlantic storms last winter were all spawned in a region near off Nova Scotia where warm tropical air meets cold polar air creating instability. Did high spring tides play a role in triggering these storms? The video below shows an animation of the horizontal tractional forces acting on the Jet Stream as spring tides sweep through the Atlantic. Maximum spring tides were experienced 3-6 January which also led to coastal flooding on UK shores.

    Early january saw the strongest tides of 2014. The figure below shows the relative magnitude of the combined solar/lunar gravitational tides. At the equinoxes spring tides at new moon and full moon  tend to be roughly equal, whereas in winter it is new moon tides that dominate. The chart below was prepared by Roberto Madrigali
    TIDES-STORM-AND-RAIN2014

    If we look in more detail at the January storm we see that large tides sweeping across the Atlantic may have affected the unstable convergence of warm tropical air and cold polar air east of Canada. This was where the very low pressure January storm was spawned.>>>>>>>>

    READ THE REST>>LINK PHISICIST CLIVE BEST

     

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