Archives de catégorie : unclassified

Cycles of Rapid Climate Warming

by Jim Steele, May 28, 2018 in WUWT


The globally averaged temperature rose 1.5°F from 1880 to today. Various narratives suggest the rise since 1950 was driven by increasing concentrations of CO2. The rising temperature before 1950 was considered natural. Since 1990, Arctic temperatures rose 2 to 3 times faster than the global average. So, are rapidly rising Arctic temperatures evidence of an impending climate crisis?

Astute students of climate history recall rapid Arctic warming has happened often and naturally. During the last Ice Age when CO2 concentrations were just half of today’s, 25 abrupt warming events happened. Arctic temperatures rose 9°F, and sometimes as much as 14°F in just 40 years. These rapid warming episodes are now called Dansgaard–Oeschger events (D-O events) in honor of the researchers who first detected them in Greenland’s ice cores. These D-O episodes affected global climate, changed ocean currents along California’s coast and altered the range of European forests.

What caused such abrupt warming? Basic physics dismisses changes in greenhouse gases or solar insolation because neither radiative effect induces such rapid warming. The most reasonable explanation suggests episodes of ventilating heat, that had accumulated in the Arctic Ocean, rapidly warmed the air.

Quote of the Week: Greta Thunberg claims to be able to “see” carbon dioxide in the air

by Anthony Watts, May 2, 2019 in WUWT


At first, I thought this had to be a joke. Then I thought it must be some sort of misinterpretation. Sadly, no.

From the website Afrinik, quoting the book –Scener ur hjärtat by Malena Ernman, Svante Thunberg:

Of course, with a ~ 410 parts per million concentration of CO2 in the atmosphere, we know that is a physical impossibility. Carbon Dioxide is a colorless and odorless gas:

 

Source:
http://www.ces.fau.edu/nasa/module-2/how-greenhouse-effect-works.php

Impacts of Small-Scale Urban Encroachment on Air Temperature Observations

by R.D. Leeper et al., 2019 in J.Appl.Met.Climatology


A field experiment was performed in Oak Ridge, TN, with four instrumented towers placed over grass at increasing distances (4, 30, 50, 124, and 300 m) from a built-up area. Stations were aligned in such a way to simulate the impact of small-scale encroachment on temperature observations. As expected, temperature observations were warmest for the site closest to the built environment with an average temperature difference of 0.31 and 0.24 °C for aspirated and unaspirated sensors respectively. Mean aspirated temperature differences were greater during the evening (0.47 °C) than day (0.16 °C). This was particularly true for evenings following greater daytime solar insolation (20+ MJDay−1) with surface winds from the direction of the built environment where mean differences exceeded 0.80 °C. The impact of the built environment on air temperature diminished with distance with a warm bias only detectable out to tower-B’ located 50 meters away.

The experimental findings were comparable to a known case of urban encroachment at a U. S. Climate Reference Network station in Kingston, RI. The experimental and operational results both lead to reductions in the diurnal temperature range of ~0.39 °C for fan aspirated sensors. Interestingly, the unaspirated sensor had a larger reduction in DTR of 0.48 °C. These results suggest that small-scale urban encroachment within 50 meters of a station can have important impacts on daily temperature extrema (maximum and minimum) with the magnitude of these differences dependent upon prevailing environmental conditions and sensing technology.

Le CO2 belge : que représente-il vraiment ?

by Jean N., 17 avril 2019 in Science-Climat-Energie


Cet article s’inscrit dans le cadre de l’activité actuelle médiatique tout azimut en Belgique, notamment relayée par les marches hebdomadaires des étudiants pour le climat. Comme vous le savez peut-être si vous êtes un lecteur fidèle de SCE, nous avons démontré dans plusieurs articles que l’hypothèse de l’effet de serre radiatif ne tient pas la route (ici, ici et ici) et n’explique pas le léger réchauffement actuel de la basse atmosphère. Les fins connaisseurs savent également qu’il existe de nombreuses publications scientifiques remettant en cause l’hypothèse de l’effet de serre radiatif (plus de 500 publications rien que pour 2018), toutes écrites par des physiciens, des chimistes, des géologues ou des climatologues. Si cette somme d’évidences vous a convaincu, le GIEC aurait alors tort sur toute la ligne et le CO2 d’origine anthropique n’aurait aucun rôle majeur déterminant la température de la basse troposphère. Cependant, admettons un instant que vous ne soyez pas convaincu et admettons donc que le GIEC ait raison. Tout ce qui est écrit dans son dernier rapport spécial devrait alors être vrai… Quelle serait alors la part de la Belgique dans le réchauffement? Asseyez-vous pour ne pas tomber, vous allez être surpris.

Figure 1. Extrait de la Figure SPM.1 du résumé pour décideurs (SPM) du rapport spécial publié par le GIEC fin 2018. Cette figure se trouve en page 8 du rapport du GIEC.

The stark reality of CO2 emissions reduction, in one graph

by Anthony Watts, March 22, 2019 in WUWT/BjornLomborg


Bjorn Lomborg‏ writes on Twitter:

“Wishful thinking: This graph starkly shows what power the 1.5°C target The black line is CO₂ emission increase last 118 years (last year was highest ever) The blue lines indicate the emissions necessary to ensure the widely politically agreed 1.5°C limit”.

 

Circular reasoning with climate models

by Dr. Wojick, March 1, 2018 in CFact


Climate models play a central role in the attribution of global warming or climate change to human causes. The standard argument takes the following form: “We can get the model to do X, using human causes, but not without them, so human causes must be the cause of X.” A little digging reveals that this is actually a circular argument, because the models are set up in such a way that human causes are the only way to get change.

The finding is that humans are the cause of global warming and climate change is actually the assumption going in. This is circular reasoning personified, namely conclude what you first assume.

This circularity can be clearly seen in what many consider the most authoritative scientific report on climate change going, although it is actually just the most popular alarmist report. We are talking about the Summary for Policymakers (SPM), of the latest assessment report (AR5), of the heavily politicized UN Intergovernmental Panel on Climate Change (IPCC). Their 29 page AR5 SPM is available here.

40387018 – the raging whirlpool

ClimateGate continues – the Mann Hockeystick University of Arizona emails are now public

by Anthony Watts, March4, 2019 in WUWT


After years of trying to suppress their release, and finally being ordered to be released by a judge, they are now public, and we have them here. This will remain as a “top post” for a day, new stories will be below this one.

There’s quite a treasure trove, but also some duplications from previous releases.

L’art de gommer les incertitudes

by Jean, N. 2 mars 5019 in ScienceClimatEnergie


Comme déjà mentionné dans un article précédent publié sur SCE, la variation de la couverture nuageuse a probablement un effet majeur sur la température moyenne globale de la basse atmosphère. Si l’on veut prédire le climat du futur comme le prétend le GIEC il faut savoir modéliser la formation des nuages. Que nous dit le dernier rapport scientifique (AR5) du GIEC à ce sujet? Le but du présent article est simplement de vous présenter quelques phrases tirées de ce rapport. La science est-elle dite?

1. Le chapitre 7 du rapport AR5 publié par le GIEC en 2013

Le chapitre 7 du rapport AR5 du GIEC[1] fait 60 pages et est consacré aux nuages et aux aérosols (le rapport AR5 complet fait au total 1535 pages). Ce chapitre 7 comporte 22 pages de références et cite plus de 1100 articles scientifiques publiés dans des revues aussi prestigieuses que Science, Nature ou PNAS. Le chapitre 7 a été écrit sous la direction de Olivier Boucher (France) et David Randall (USA), deux spécialistes du domaine. Nous n’allons pas ici remettre en question la validité de ce chapitre. Nous allons simplement vous présenter quelques phrases tirées du rapport. Comme le rapport est écrit en anglais nous vous proposerons ci-dessous une “traduction maison” des phrases qui nous paraissent les plus importantes, assorties parfois de quelques explications pour bien les comprendre. Les lettres entre crochets ([A] à [P]) renvoient simplement au texte original en anglais, donné en Annexe du présent article.

New Findings From German Scientists Show Changes in Precipitation Over Europe Linked To Solar Activity

by P. Gosselin, February 15, 2019 in NoTricksZone


A significant number of scientists say that the Earth’s climate is in large part impacted by solar activity, and less so by trace gas CO2 concentration. German scientists present new findings showing a link between solar activity and precipitation in Europe.
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How Changes on the Sun Influences Rain

A balanced level of precipitation provides the basis for a wide range of economic and social activities in Europe. Particularly agriculture, drinking water supply and inland waterway transport are directly affected. However, the amount of rain fluctuates strongly from year to year. While it may pour torrentially in one year, rain may remain absent for weeks in other year. The population is used to this variability and usually knows how to deal with it.

But what is behind the strong changes? A system, or pure atmospheric noise?

Pas de réchauffement pour les zones éloignées des océans

by Dr. Jean N., 16 janvier 2019 in ScienceClimatEnergie


La théorie radiative de l’effet de serre prédit que la température de la basse atmosphère augmente lorsque le taux de CO2 croît. Si l’on prend par exemple une très vaste région, comme la Chine centrale ou le Midwest américain, qui couvrent tous deux des centaines de milliers de km2, on devrait donc observer un accroissement des températures moyennes de la basse atmosphère en fonction du temps. Effectivement, dans ces régions, et comme pour tout l’hémisphère Nord, le taux de CO2 n’a fait qu’augmenter depuis le début des mesures par spectrométrie infra-rouge en 1959. Cependant, une étude récente vient de montrer que la température moyenne n’aurait pas augmenté dans ces vastes régions, et ce malgré l’augmentation du taux de CO2 atmosphérique. L’étude en question a été publiée dans Energy & Environment en 2018 par deux chercheurs danois de la Danish Technical University, Frank Lansner et Jens Pedersen. Il faut rester prudent, mais si cette étude est confirmée, il s’agirait d’un sérieux problème pour la théorie radiative de l’effet de serre.

 

Figure 1. Anomalie de température pour la Sibérie centrale entre 1900 et 2010 (voir article)

My experience at the German Bundestag’s Environment Committee in a pre-COP24 discussion

by Dr Shaviv, December 7, 2018 in ScienceBits


Three minutes is not a lot of time, so let me be brief. I’ll start with something that might shock you. There is no evidence that CO2 has a large effect on climate. The two arguments used by the IPCC to so called “prove” that humans are the main cause of global warming, and which implies that climate sensitivity is high, are that: a) 20th century warming is unprecedented, and b) there is nothing else to explain the warming.

These arguments are faulty. Why you ask?

We know from the climate-gate e-mails that the hockey stick was an example of shady science. The medieval warm period and little ice ages were in fact global and real.  And, although the IPCC will not admit so, we know that the sun has a large effect on climate, and on the 20th century warming in particular.

In the first slide we see one of the most important graphs that the IPCC is simply ignoring. Published already in 2008, you can see a very clear correlation between sea level change rate from tide gauges, and solar activity. This proves beyond any doubt that the sun has a large effect on climate. But it is ignored.

 

Polar Bears’ Arctic Sea Ice Ecosystem Not In Danger Of Melting Away

by S.J. Crockford, October 31, 2018 in ClimateChangeDispatch


What’s a good analogy for sea ice as essential polar bear habitat? Biologist Andrew Derocher claims that the soil in a forest is appropriate because without the soil you can’t have the forest ecosystem.

However, that’s a specious comparison because the amount of soil in a forest does not change markedly with the seasons the way that Arctic sea ice does.

A much better analogy is a big pond that dries up a bit every summer. The amount of habitat available to sustain aquatic plants, amphibians and insects is reduced in the dry season but many species have special adaptations for surviving reduced water availability.

Higher sea surface temperature in the northern South China Sea during the natural warm periods of late Holocene than recent decades

by Hong Yan et al., November 2014, in ChineseSciBull


The large-scale syntheses of global mean temperatures in IPCC fourth report suggested that the Northern Hemisphere temperature in the second half of the 20th century was likely the highest in at least the past 1,300 years and the 1990s was likely the warmest decade. However, this remains debated and the controversy is centered on whether temperatures during the recent half century were higher than those during the Medieval Climate Anomaly (MCA, AD 800–1300) and the Roman Warm Period (RWP, BC 200–AD 400), the most recent two natural warm periods of the late Holocene. Here the high resolution sea surface temperatures (SSTs) of two time windows around AD 990 (±40) and AD 50 (±40), which located in the MCA and RWP respectively, were reconstructed by the Sr/Ca ratio and δ 18O of Tradacna gigas shells from the northern South China Sea. The results suggested that the mean SSTs around AD 990 (±40) and AD 50 (±40) were 28.1 °C and 28.7 °C, 0.8 °C and 1.4 °C higher than that during AD 1994–2005, respectively. These records, together with the tree ring, lake sediment and literature records from the eastern China and northwest China, imply that the temperatures in recent decades do not seem to exceed the natural changes in MCA, at least in eastern Asia from northwest China to northern SCS.

L’écologie politique sera scientifique ou ne sera plus (partie 2)

by JP Riou, 9 octobre 2018 in EuropeanScientist


L’ écologie a renoué avec l’environnement le lien fondamental et sacré qui le relie à l’homme. Par cette communion, elle remplit le vide laissé par les religions dans un contexte d’explosion technologique. Mais elle fait semblant d’ignorer que le fossé s’élargit de toutes parts entre la déclinaison politique de ses principes et le bilan de ses résultats.

La dimension mondiale du phénomène et les sommes inédites qui lui sont consacrées justifient une tentative d’analyse de son origine et de sa démarche, ainsi que de ses ressorts cachés et des conséquences géopolitiques qu’on peut en attendre.

Ces 2 faces de l’écologie politique sont l’objet des 2 parties du présent article.

Pour la première parie voir ici