The short answer to the question posed in the title to this article is virtually and practically nothing. They definitely do not tell us what is claimed, that is, accurate representation of the state of the atmosphere including temperature in individual years. This is why one of the world’s experts on atmospheric chemistry and ice cores Zbigniew Jaworowski M.D., Ph.D., D.Sc., wrote,
“It was never experimentally demonstrated that ice core records reliably represent the original atmospheric composition.”
La fermeture des centrales nucléaires belges pourrait entraîner une augmentation de 50% des émissions de CO2 liées à la production d’énergie d’ici 2030, selon le professeur d’économie Johan Albrecht (UGent – Université de Gand), qui est également membre de l’institut de réflexion Itinera. Cela alors que le gouvernement fédéral et les entités fédérées doivent négocier dans les semaines à venir le Pacte énergétique, qui doit fixer l’avenir de la production d’électricité en Belgique.
Other countries are failing to meet their targets, but we’re not only achieving them, we’re overdoing it. And this is despite our obvious handicaps: like that we have rapid population growth, are further from everywhere and anywhere* except for Antarctica, and we’re the largest coal exporter in the world;
by David Kirtley, December 28, 2017, in SkepticalScicence
In Part 1, we learned about carbon isotopes: how 14C forms in the atmosphere, how different isotopes move through the Carbon Cycle, and how isotopic measurements reveal clues about our changing climate. In this post we will look at how measurements of changing isotopic ratios are described.
by Fred Pearce, December 19, 2017 in Yale Environment360
In September, some 200 scientists wrote to the EU insisting that “bioenergy [from forest biomass] is not carbon-neutral” and calling for tighter rules to protect forests and their carbon. Yet just a month later, EU ministers rubber-stamped the existing carbon accounting rules, reaffirming that the burning of wood pellets is renewable energy.
For the first time scientists have directly observed living bacteria in polar ice and snow — an environment once considered sterile. “As microbial activity and its influence on its local environment has never been taken into account when looking at ice-core gas samples it could provide a moderate source of error in climate history interpretations.”
Les prévisions climatiques à très long terme (2100) sont établies à l’aide de modèles qui ne sont rien d’autre des logiciels très complexes, dont le but est de reproduire le comportement du climat terrestre.
Comme on ne peut pas décrire ce qui se passe en tous les points de la terre, celle-ci est découpée en mailles de quelques centaines de kilomètres de côté. Les modèles utilisés par le GIEC pour son cinquième rapport d’évaluation (2013) avaient des résolutions relativement grossières (supérieures à 100 km). La situation évolue toutefois rapidement et les modèles climatiques les plus récents auraient une résolution plus fine (de l’ordre de 20 km).
New research yields old result: Climate warming slow, steady. Observed value is half that of CMIP5 climate models.
The rate at which Earth’s atmosphere is warming has not significantly accelerated over the past 23 years, according to research at The University of Alabama in Huntsville (UAH).
If you take away the transient cooling in 1983 and 1992 caused by two major volcanic eruptions in the preceding years, the remaining underlying warming trend in the bottom eight kilometers (almost five miles) of the atmosphere was 0.096 C (about 0.17° Fahrenheit) per decade between January 1979 and June 2017.
That was unexpectedly close to the 0.09 C warming trend found when similar research was published in 1994 with only 15 years of data, said Dr. John Christy, director of UAH’s Earth System Science Center.
According to the most basic precepts of anthropogenic global warming (AGW), variations in CO2 concentrations exert significant control on sea surface temperatures, glaciers, sea levels, and generalized climate dynamics (i.e., precipitation patterns).
In particular, high CO2 concentrations, driven by human activity, are presumed to cause dangerously warming ocean waters, rapid glacier melt and sea level rise, and overall disruption to the Earth’s biosphere.
Newly published scientific papers wholly undermine this popularized conceptualization.
In fact, according to Bertrand et al. (2017), there has been a “marked cooling” of sea surface temperatures in the southernmost South America region during the last ~800 years — 3°C to 4°C colder than during the Medieval and Roman warm periods — that has continued unabated into “the most recent decades”.
Sometimes you have to wonder which are the biggest fraud: Germany’s claim that its cars are clean, or its claim of being a leader in climate protection. Both, it turns out, are very fake and even downright frauds.
While German Chancellor Angela Merkel and German activists like going around and scolding Donald Trump for his “irresponsible” stance on “greenhouse” gas emissions, it is coming to light that Germany’s climate posturing is indeed a total swindle.
In addition, we consider temperature dependent natural emission and absorption rates, by which the paleoclimatic CO2 variations and the actual CO2 growth rate can well be explained. The anthropogenic contribution to the actual CO2concentration is found to be 4.3%, its fraction to the CO2 increase over the Industrial Era is 15% and the average residence time 4 years.”
Though advocates of the dangerous anthropogenic global warming (AGW) narrative may not welcome the news, evidence that modern day global warming has largely been driven by natural factors – especially solar activity – continues to pile up.
Much of the debate about the Sun’s role in climate change is centered around reconstructions of solar activity that span the last 400 years, which now include satellite data from the late 1970s to present.
It started as a nice simple idea: There is a finite amount of Carbon that humanity can burn before the planet warms above 2C. This idea was based on AR5 Earth Systems Models (ESMs) ‘showing’ that the relationship between global temperatures and cumulative emissions was linear. At last the IPCC had something easy for world leaders to understand! This was all nicely summarised in Figure SPM-10, shown below. The Paris accord is essentially derived from this one figure.
The annual assessment of global greenhouse gas (GHG) emissions by the JRC and the Netherlands Environmental Assessment Agency (PBL) confirms that CO2 emissions have stalled for the third year in a row.
The report provides updated results on the continuous monitoring of the three main greenhouse gases: carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O).
(…) It appears that the much larger changes predicted by other models arise from additional water vapor evaporated into the atmosphere and not from the CO2 itself (…)
(…) Assuming a doubling of CO2 by the late 21st century (assuming no positive water vapor feedback), we should likely expect to see no more than about 0.3-0.5°C global surface warming and certainly not the 2-5°C warming that has been projected by the GCMs [global circulation models (…)
by Hermann Harde, March 30, 2017 in Inter.J.Atm.Sciences
Including solar and cloud effects as well as all relevant feedback processes our simulations give an equilibrium climate sensitivity of = 0.7°C (temperature increase at doubled CO2) and a solar sensitivity of = 0.17°C (at 0.1% increase of the total solar irradiance). Then CO2 contributes 40% and the Sun 60% to global warming over the last century.
A recently highlighted paper published by atmospheric scientists Scafetta et al., (2017) featured a graph (above) documenting post-2000 trends in the published estimates of the Earth’s climate sensitivity to a doubling of CO2 concentrations (from 280 parts per million to 560 ppm).
Dans quelle mesure les émissions anthropiques qui s’élèvent à 9 Giga Tonnes par an (dont 1,5 dues au changement d’utilisation des sols) perturbent le cycle du carbone contribuant à l’augmentation de la concentration de CO2 dans l’atmosphère?
Les émissions américaines de CO2 liées à l’énergie ont baissé de 1,7% en 2016. Elles ont toutefois encore atteint près de 5,2 milliards de tonnes l’an dernier, ce qui fait toujours des États-Unis le 2e émetteur mondial après la Chine.
by Nicole Jacobs, October 3, 2017 in ClimateChangeDispatch
The report, which bases its CO2 emissions estimates off International Energy Agency (IEA) and BP data through 2016, found the global CO2 levels essentially remained flat in 2015 and 2016. As BP noted earlier this year, the global trend is “well below the 10-year average growth of 1.6% and a third consecutive year of below-average growth” and that “during 2014-16, average emissions growth has been the lowest over any three-year period since 1981-83.”
A number of authors, including the IPCC, have argued that climate models have systematically overstated the rate of global warming in recent decades. A recent paper by Millar et al. (2017) presented the same finding in a diagram of temperature change versus cumulative carbon emissions since 1870.
La géologie, une science plus que passionnante … et diverse