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climate-debate

Origins of climate changes

by A. Préat, Oct 13, 2023 in Science,Climate,Energy

An obvious fact

No one denies that the Earth’s temperature has been rising slightly by around 0.9°C for almost 125 years (see Soon et al., 2023 for details). This recent increase is minimal (0.6°C between 1975 and 1998) and framed by periods of temperature decrease of similar amplitude (1880-1910 and 1940-1975).

Our media, including the IPCC and many scientists, claim that the sole culprit for the current temperature rise is atmospheric CO2 levels, which are linked to human activity. This is a hypothesis, since no link has yet been established between temperature and CO2 content – quite the contrary (Davison, 2023). The climate alarmism (Watts, 2023) that occupies the front pages of our newspapers is not justified, as we shall see.

 

Geological cycles

This increase over more than a century is by no means exceptional; it has occurred many times before with much greater amplitudes, up to 20 times the recent increase, and over equally short periods. For example, in the Pleistocene (2.58 million years or ‘Ma’ to 11,700 years), researchers have counted more than 25 cycles with abrupt increases of +8°C to +16°C in 50 years each time (= ‘Dansgaard-Oeschger cycles’, see Boers, 2018, SCE, 2020 and here). These abrupt increases are to be compared with the recent increase of 0.3°C in 50 years (average 1880-2008). See SCE and SCE. Such cycles also exist in older geological periods, for example in the Jurassic (CNRS ; Boulila et al., 2022).

Several high-level journals (including Nature) have shown that the increase in CO2 follows that of temperature, mainly because of CO2 degassing in the oceans (see references in SCE, 2021). Note also that the current atmospheric CO2 content (0.04% or 400 ppm – ‘parts per million’) is twice what it was during the Dansgaard-Oeschger cycles, which last between 1,500 and 4,500 years. It’s also worth noting that current atmospheric CO2 levels are the lowest since the Earth’s existence (4.65 billion years ago), apart from a short period of 100 Ma (in the Permian-Carboniferous transitional period) with the same levels as today. For almost 2% of its history, the level of CO2  in the Earth’s atmosphere has thus varied from several thousand ppm to several percent, i.e., from 3 to 25 times higher since the Cambrian, 541 Ma ago (geological scale here), when biodiversity exploded (with metazoans, here), and even much earlier during the Precambrian (Thomas, 2000 ; Préat, 2019 ; Lehmer et al., 2020). CO2 levels were sometimes higher than today’s during ice ages.  Examples of warmer and colder periods are the rule in geology; just think of the Arctic (Svarlbad) at the beginning of the Holocene, around 11,000 years ago, which was +7°C warmer than the present, when CO2 levels were half the current level (Richard, 2020). Continuer la lecture de Origins of climate changes →

climate-debate

Satellite Data Shows Antarctica Continues Adding Ice Mass, Lowering Sea Level

by Dr. M. Wielicki, Oct 19 2023 in Climate ChangeDispatch

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Antarctica presented a more complex picture. While the continent as a whole lost about 130 gigatons of ice each year during a similar timeframe, the loss was most pronounced in West Antarctica, especially around the Amundsen Sea sector.

This accelerated melting in West Antarctica is a matter of particular concern for researchers, as it is claimed to have the potential to destabilize larger sections of the Antarctic ice sheet, leading to more pronounced sea-level rise in the future.

Mass change of the Antarctic Ice Sheet from April 2002 to September 2020. Time series of mass change from the GRACE and GRACE-FO missions, M(t), for the entire Antarctic Ice Sheet (green) and its division into East Antarctica (blue), West Antarctica (red), and the Antarctic Peninsula (yellow). The vertical lines indicate the end of the GRACE and the beginning of the GRACE-FO monthly data availability (June 2017 and July 2018, respectively). Shadings represent 1-σuncertainties. Equivalent sea-level contribution (right axis) is approximated as 1 mm sea-level rise for 360 Gt of ice mass loss. Source

However, since early 2020, nearly 1,000 gigatons of ice have been added to Antarctica. This remarkable ice gain represents nearly one-third of the total ice loss since 2002.

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climate-debate

Physicists: CO2 Only Affects 10% Of IR In 3% Of The Troposphere

by K. Richard, Oct 19, 2023 in NoTricksZone

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There are many scientifically invalid assumptions in the “greenhouse gas hypothesis” that the editors of a journal, Earth System Dynamics (ESD), now insist they will never again allow to be subjected to critical analysis in future publications, as the editors of this journal are committed to only publishing studies agreeing with the “consensus.”

In a editorial comment published in the MDPI journal Entropy responding to an editorial written by the editors of ESD, two Portuguese scientists (Khmelinskii and Woodcock, 2023) identify at least 8 assumptions in the “greenhouse gas hypothesis” that lack scientific validation. Despite the lack of observational evidence supporting their viewpoints, proponents of the anthropogenic global warming hypothesis prefer to dismiss and ignore challenges to what they believe is the “consensus” – the opposite of what the scientific method requires.

For brevity’s sake, only a few of the challenges are summarized below.

• CO2 can only absorb 10% of all radiation in the specific IR bands CO2 affects. CO2 “absorbs absolutely nothing at all other IR wavelengths.” Thus, CO2 has no effect on IR in 90% of absorption bands.

• CO2 can only absorb IR in the top 300 m, or 0.3 km, of the surface-troposphere, which is 10 km thick. Thus, CO2 can only affect 10% of the IR in 3% of the surface-troposphere, where climate change occurs.

• Because of its vanishingly small effects, doubling CO2 concentrations could only lead to a 0.015°C surface temperature change, at most. Understatedly, “this effect would not even be measurable.”

• Uncertainty in the Earth’s radiation balance is ±17 W/m². The estimated radiation imbalance is 0.6 W/m², which is “orders of magnitude” smaller than the uncertainty in its derivation. Thus, the “global balance of energy fluxes…cannot be derived from measured fluxes“… and this “profoundly affects our ability to understand how Earth’s climate responds to increasing concentrations of greenhouse gases.”

The editors at ESD do not view observational uncertainty – or questions regarding the magnitude of CO2’s effects – as worthy of critical analysis.

 

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