miércoles, 18 de enero de 2017

¿Nunca hubo una pausa en el CGA?

Plazaeme analiza la cuestión de la pausa del aumento de temperaturas en el siglo XXI, la cuestión de las "correcciones" de los modelos, recogiendo numerosas citas sobre dicha causa en los últimos años. 
Artículo de Plazamoyua: 
pause
Copio una lista de citas de un comentarista (catweazle666) en una entrada del blog de Judith Curry [–>]. Me ha apatecido rescatarla, porque tiene mérito la recopilación.
La cuestión es que primero los escépticos empezaron a señalar un pausa en el calentamiento. Y luego los alarmistas, cuando no les quedaba más remedio, pasaron de negarla a justificarla. Pero ver, la veían. Y no es que ahora hayan cambiado de opinión, sino que han cambiado de datos. Corrigiéndolos.
Nadie ha demostrado que las últimas correcciones estén injustificadas. Pero eso no significa gran cosa. Sacar una serie de temperatura global de la superficie de la tierra no es un asunto baladí. Más bien es un pollo de narices. Y siempre hay nuevos detalles que se pueden pensar, que producen cambios.
El problema es cuando a ese pollo le añades un consenso. Vaya, un consenso, además, militante. Quiero decir, en el que se acosa al discrepante. Porque eso implica que tienes a los constructores de series de temperatura pensando todos del mismo lado. El consenso del achicharramiento global. Y la predicción normal en esas condiciones es que piensen en las correcciones que apoyen al consenso, y no dediquen mucho pensamiento a otras correcciones que podría haber en sentido contrario, igualmente válidas. No creo que esta sea una idea muy controvertida. Parece demasiado obvia.
Nota: En las series de temperatura global medida por satélite no ha dejado de existir la pausa. Sí se acabó con El Niño reciente, en 2015. Era algo más o menos inevitable, y ya veremos cómo queda dentro de dos o tres años, cuando se equilibre el efecto.
Nota: Lo de la pausa resulta extraordinariamente mediático, pero su relevancia es relativa. Podría sugerir un cambio de ciclo, de haberla y ser larga. Pero lo que más importa es de cuánto calentamiento hablamos; y si se parece al de los modelos o es como la mitad. Y la medida de eso es la tendencia desde hacia 1975, cuando empezó el llamado Calentamiento Global Acojonante.
Hablando de las famosas correcciones, pongo un gráfico para situarnos. En este caso son las de la NASA [Desde Real Climate –>].
correcciones-temperaturas-nasa
En el panel de arriba se ve la comparación de las correcciones últimas con las anteriores (el historial de correcciones es muuuy largo). Como se aprecia, la diferencia es ridícula. Pero es que estamos contando ángeles sobre la cabeza de un alfiler, y es un prodigio. Un prodigio que quita o pone pausa.
En el panel de abajo, la serie de la NASA con y sin correcciones. El efecto principal de la corrección es lavar la cara de los modelos climáticos, incapaces de reproducir el calentamiento -obviamente natural- entre 1915 y 1945.
Y ya la lista de citas prometida.
Dr. Phil Jones – CRU emails – 5th July, 2005 – “The scientific community would come down on me in no uncertain terms if I said the world had cooled from 1998. OK it has but it is only 7 years of data and it isn’t statistically significant….”
__________________
Dr. Phil Jones – CRU emails – 7th May, 2009 – ‘Bottom line: the ‘no upward trend’ has to continue for a total of 15 years before we get worried.’
__________________
Dr. Judith L. Lean – Geophysical Research Letters – 15 Aug 2009 – “…This lack of overall warming is analogous to the period from 2002 to 2008 when decreasing solar irradiance also countered much of the anthropogenic warming…”
__________________
Dr. Kevin Trenberth – CRU emails – 12 Oct. 2009 – “Well, I have my own article on where the heck is global warming…..The fact is that we can’t account for the lack of warming at the moment and it is a travesty that we can’t.”
__________________
Dr. Mojib Latif – Spiegel – 19th November 2009 – “At present, however, the warming is taking a break,”…….”There can be no argument about that,”
__________________
Dr. Jochem Marotzke – Spiegel – 19th November 2009 – “It cannot be denied that this is one of the hottest issues in the scientific community,”….”We don’t really know why this stagnation is taking place at this point.”
__________________
Dr. Phil Jones – BBC – 13th February 2010 – “I’m a scientist trying to measure temperature. If I registered that the climate has been cooling I’d say so. But it hasn’t until recently – and then barely at all. The trend is a warming trend.”
__________________
Dr. Phil Jones – BBC – 13th February 2010
[Q] B – “Do you agree that from 1995 to the present there has been no statistically-significant global warming”[A] “Yes, but only just”.
__________________
Prof. Shaowu Wang et al – Advances in Climate Change Research – 2010 – “…The decade of 1999-2008 is still the warmest of the last 30 years, though the global temperature increment is near zero;…”
__________________
Dr. B. G. Hunt – Climate Dynamics – February 2011 – “Controversy continues to prevail concerning the reality of anthropogenically-induced climatic warming. One of the principal issues is the cause of the hiatus in the current global warming trend.”
__________________
Dr. Robert K. Kaufmann – PNAS – 2nd June 2011 – “…..it has been unclear why global surface temperatures did not rise between 1998 and 2008…..”
__________________
Dr. Gerald A. Meehl – Nature Climate Change – 18th September 2011 – “There have been decades, such as 2000–2009, when the observed globally averaged surface-temperature time series shows little increase or even a slightly negative trend1 (a hiatus period)….”
__________________
Met Office Blog – Dave Britton (10:48:21) – 14 October 2012 – “We agree with Mr Rose that there has been only a very small amount of warming in the 21st Century. As stated in our response, this is 0.05 degrees Celsius since 1997 equivalent to 0.03 degrees Celsius per decade.”Source: metofficenews.wordpress.com/2012/10/14/met-office-in-the-media-14-october-2012
__________________
Dr. James Hansen – NASA GISS – 15 January 2013 – “The 5-year mean global temperature has been flat for a decade, which we interpret as a combination of natural variability and a slowdown in the growth rate of the net climate forcing.”
__________________
Dr Doug Smith – Met Office – 18 January 2013 – “The exact causes of the temperature standstill are not yet understood,” says climate researcher Doug Smith from the Met Office.[Translated by Philipp Mueller from Spiegel Online]
__________________
Dr. Virginie Guemas – Nature Climate Change – 7 April 2013 – “…Despite a sustained production of anthropogenic greenhouse gases, the Earth’s mean near-surface temperature paused its rise during the 2000–2010 period…”
__________________
Dr. Judith Curry – House of Representatives Subcommittee on Environment – 25 April 2013 – ” If the climate shifts hypothesis is correct, then the current flat trend in global surface temperatures may continue for another decade or two,…”
__________________
Dr. Hans von Storch – Spiegel – 20 June 2013 – “…the increase over the last 15 years was just 0.06 degrees Celsius (0.11 degrees Fahrenheit) — a value very close to zero….If things continue as they have been, in five years, at the latest, we will need to acknowledge that something is fundamentally wrong with our climate models….”
__________________
Professor Masahiro Watanabe – Geophysical Research Letters – 28 June 2013 – “The weakening of k commonly found in GCMs seems to be an inevitable response of the climate system to global warming, suggesting the recovery from hiatus in coming decades.”
__________________
Met Office – July 2013 – “The recent pause in global warming, part 3: What are the implications for projections of future warming?………..Executive summaryThe recent pause in global surface temperature rise does not materially alter the risks of substantial warming of the Earth by the end of this century.”
Source: etoffice.gov.uk/media/pdf/3/r/Paper3_Implications_for_projections.pdf
__________________
Professor Rowan Sutton – Independent – 22 July 2013 – “Some people call it a slow-down, some call it a hiatus, some people call it a pause. The global average surface temperature has not increased substantially over the last 10 to 15 years,”
__________________
Dr. Kevin Trenberth – NPR – 23 August 2013 – “They probably can’t go on much for much longer than maybe 20 years, and what happens at the end of these hiatus periods, is suddenly there’s a big jump [in temperature] up to a whole new level and you never go back to that previous level again,”
__________________
Dr. Yu Kosaka et. al. – Nature – 28 August 2013 – “Recent global-warming hiatus tied to equatorial Pacific surface coolingDespite the continued increase in atmospheric greenhouse gas concentrations, the annual-mean global temperature has not risen in the twenty-first century…”
__________________
Professor Anastasios Tsonis – Daily Telegraph – 8 September 2013 – “We are already in a cooling trend, which I think will continue for the next 15 years at least. There is no doubt the warming of the 1980s and 1990s has stopped.”
__________________
Dr. Kevin E. Trenberth – Nature News Feature – 15 January 2014 – “The 1997 to ’98 El Niño event was a trigger for the changes in the Pacific, and I think that’s very probably the beginning of the hiatus,” says Kevin Trenberth, a climate scientist…
__________________
Dr. Gabriel Vecchi – Nature News Feature – 15 January 2014 – “A few years ago you saw the hiatus, but it could be dismissed because it was well within the noise,” says Gabriel Vecchi, a climate scientist…“Now it’s something to explain.”…..
__________________
Professor Matthew England – ABC Science – 10 February 2014 – “Even though there is this hiatus in this surface average temperature, we’re still getting record heat waves, we’re still getting harsh bush fires…..it shows we shouldn’t take any comfort from this plateau in global average temperatures.”
__________________
Dr. Jana Sillmann et al – IopScience – 18 June 2014 – Observed and simulated temperature extremes during the recent warming hiatus“This regional inconsistency between models and observations might be a key to understanding the recent hiatus in global mean temperature warming.”
__________________
Dr. Young-Heon Jo et al – American Meteorological Society – October 2014 -“…..Furthermore, the low-frequency variability in the SPG relates to the propagation of Atlantic meridional overturning circulation (AMOC) variations from the deep-water formation region to mid-latitudes in the North Atlantic, which might have the implications for recent global surface warming hiatus.”

Artículos Relacionados por categorias


No hay comentarios:

Publicar un comentario en la entrada