Archives par mot-clé : Recent

climate and geology

Elegantly modeling Earth’s abrupt glacial transitions

by American Institute of Physics, Mar 7, 2023 in ScienceDaily

Proxy data — indirect records of the Earth’s climate found in unlikely places like coral, pollen, trees, and sediments — show interesting oscillations approximately every 100,000 years starting about 1 million years ago. Strong changes in global ice volume, sea level, carbon dioxide concentration, and surface temperature indicate cycles of a long, slow transition to a glacial period and an abrupt switch to a warm and short interglacial period.

Milutin Milankovitch hypothesized that the timing of these cycles was controlled by the orbital parameters of the Earth, including the shape of its path around the sun and the tilt of the planet. A slightly closer orbit or more tilted planet could create a small increase in solar radiation and a feedback loop that leads to massive changes in climate. This idea suggests that there may be some predictability in the climate, a notoriously complex system.

In Chaos, by AIP Publishing, Stefano Pierini of Parthenope University of Naples proposed a new paradigm to simplify the verification of the Milankovitch hypothesis.

“The main motivation behind this study was the wish to characterize and illustrate the Milankovitch hypothesis in a simple, elegant, and intuitive way,” Pierini said.

Many models suggest that Milankovitch is correct; however, such methods are often detailed and study specific. They incorporate climate feedback loops — for example, increased ice cover reflects more radiation back into space, leading to further cooling and more ice cover — as threshold crossing rules. This means that an abrupt jump in climate only occurs once a parameter reaches a given tipping point.

Pierini’s “deterministic excitation paradigm” combines the physics concepts of relaxation oscillation and excitability to link Earth’s orbital parameters and the glacial cycles in a more generic way. The relaxation oscillation component describes how the climate slowly returns to its original glacier state after it is disturbed. At that point, the excitability piece of the model captures the external orbital changes and triggers the next glacial cycle.

By using his own threshold crossing rules and adopting a classical energy-balance model, Pierini obtained correct and robust timing of the most recent glacial cycles.`

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climate-debate

Greenland Temperatures Rose 1°C In 1994 … Since Then They Have Been ‘Relatively Constant’

by K. Richard, Feb 27, 2023 in NoTricksZone

A warming event that spans only one year, with decades of stable temperatures before and after, would not appear to align with rapidly rising human CO2 emissions or a gradually rising atmospheric CO2 concentration.

From 1958 to 2020, as CO2 rose from 320 ppm to 410 ppm, Greenland had a warming period of 1°C that lasted one year – 1994. Over the next 26 years (1994-2020) and spanning the years 1958 to 1993, there have been “relatively constant” temperatures across Greenland (Zhang et al., 2022).

These temperature trends appear to align much better with phases of the North Atlantic Oscillation (NAO), Greenland blocking indexes (GBI), and volcanism better than they do with any anthropogenic causal agents.

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better to know...?, climate-debate

Warmth Limits For Tree Growth Affirm Austria Was 4-7°C Warmer Than Today 2000 Years Ago

by K. Richard, Jan 23, 2023 in NoTricksZone

Robust evidence from bison remains recovered from the Austrian Alps in 2020 and 2021 invalidate claims modern Alpine temperatures are unusually warm.

A new study suggests that from about 6000 to 1200 years ago European bison fed on deciduous tree/vegetation that grew at Alpine altitudes reaching around 800 m higher than they do today.

Known beech and oak tree growth warmth thresholds – the required number of days per year above a minimum temperature limit – thus affirm Austria needed to be 4-7°C warmer than now during this period (~2000 years ago).

“[T]he beech limit but also the forest line during the »wisent time« (6,000 to 1,200 years before today) was much higher and the average summer temperature had to be at least 3 to 6 °C higher than today. Remarkable is a palynological record (Ressl, 1980) from the shaft cave Stainzerkogelschaft near Lunz am See. Remains of wisent were found in the shaft (1,463 m, see Tab. 3). The clay with a skull fragment with horncores inside was examined palynologically. The dominating pollen were from alder (Alnus), oak (Quercus) and linden tree (Tilia). The oak boundary (boundary between colline and montane vegetation stages) today lies between 400 and 800 metres in the Northern Alpine Alps (Grabherr et al., 2004). Oaks (Quercus) at an altitude of 1,450 metres around 2,000 years ago also indicate a climate approximately 4 to 7 °C warmer than today.”

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climate-debate, Cooling

Good 2022 Climate News the MSM didn’t tell you

by J. Vinos, Jan 8, 2023 in WUWT

No minimally informed person denies that climate changes. The climate has always changed. Since 1860 the predominant climate change has been warming, which is fortunate because if we had a winter like those of 1800-1850, we would be in for a shock. No one has been able to prove that global warming is primarily a consequence of our emissions. It is reasonable to assume that increased CO2 has contributed to warming since the mid-20th century when our CO2 emissions increased significantly, but no one knows how much they have contributed, no matter how much the Intergovernmental Panel on Climate Change (IPCC) insists that “humans are the dominant cause of observed global warming over recent decades.”(IPCC AR6, page 515).

There is no evidence for this statement. I know this because I have read thousands of scientific papers looking for it. And no, computer models are not evidence of anything but the programming skills of their authors. Models and their predictions are constantly changing and when our knowledge of climate changes, they must be redone.

The absolute lack of evidence contrasts sharply with the decision to cut our CO2 emissions to zero by completely changing our fossil fuel-based energy system and calling CO2 a pollutant—when it is as essential to life as oxygen. All this while most of the world doesn’t give a damn about emissions and many are only on board for the promised money.

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climate-debate

UAH Global Temperature Update: 2022 was the 7th Warmest of 44-Year Satellite Record

by R. Spencer, Jan 3, 2023 in GlobalWarming

December of 2022 finished the year with a global tropospheric temperature anomaly of +0.05 deg. C above the 1991-2020 average, which was down from the November value of +0.17 deg. C.

The average anomaly for the year was +0.174 deg. C, making 2022 the 7th warmest year of the 44+ year global satellite record, which started in late 1978. Continuing La Nina conditions in the Pacific Ocean have helped to reduce global-average temperatures for the last two years. The 10 warmest years were:

  • #1 2016 +0.389
  • #2 2020 +0.358
  • #3 1998 +0.347
  • #4 2019 +0.304
  • #5 2017 +0.267
  • #6 2010 +0.193
  • #7 2022 +0.174
  • #8 2021 +0.138
  • #9 2015 +0.138
  • #10 2018 +0.090

The linear warming trend since January, 1979 continues at +0.13 C/decade (+0.12 C/decade over the global-averaged oceans, and +0.18 C/decade over global-averaged land).

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better to know...?, climate-debate, Cooling

2022, Seventh Warmest Year: Warming Slows Down

by Andy May,  Jan 7, 2023 in Petrophysicist

No minimally informed person denies that climate changes. The climate has always changed. Since 1860 the predominant climate change has been warming, which is fortunate because if we had a winter like those of 1800-1850, we would be in for a shock. No one has been able to prove that global warming is primarily a consequence of our emissions. It is reasonable to assume that increased CO2 has contributed to warming since the mid-20thcentury when our CO2 emissions increased significantly, but no one knows how much they have contributed, no matter how much the Intergovernmental Panel on Climate Change (IPCC) insists that “humans are the dominant cause of observed global warming over recent decades.” (IPCC AR6, page 515).

There is no evidence for this statement. I know this because I have read thousands of scientific papers looking for it. And no, computer models are not evidence of anything but the programming skills of their authors. Models and their predictions are constantly changing and when our knowledge of climate changes, they must be redone.

The absolute lack of evidence contrasts sharply with the decision to cut our CO2 emissions to zero by completely changing our fossil fuel-based energy system and calling CO2 a pollutant—when it is as essential to life as oxygen. All this while most of the world doesn’t give a damn about emissions and many are only on board for the promised money.

To get to the good news about global warming we need to look at variations in the rate of global warming, i.e., the speed of warming. Today we are going to use satellite-calculated global temperature data from the University of Alabama in Huntsville, UAH 6.0. They are plotted in Figure 1.

Figure 1. UAH satellite global temperature anomaly data in °C relative to the mean from 1991 to 2020. In green is the linear trend of the series (+0.13 ºC/decade) and in blue is the linear trend since 2016. Data: UAH 6.0Graph: Woodfortrees.

As we can see, the temperature trend decreases since 2016, so 2022 is the seventh warmest year. For 7 years the planet has been cooling. Does that mean that warming is over? No, periods of 7 years of cooling are frequent in the record, there being 8 of them since 1979, and the warming continues. But there is only one period of more than 15 years of cooling, from 1998 to 2014, that appears in the record for the last 45 years. It is known as the “Pause.”

To analyze the evolution of the warming rate, we subtract from each monthly data the previous one to calculate the monthly increase. We then deseasonalize the monthly increase by finding the 12-month moving average to remove a lot of the noise. Finally, we calculate the 15-year average warming rate in °C/decade by calculating the 180-month moving average and multiplying the resulting data by 120.

Figure 2. Evolution of the warming rate for 15-year periods between 1979 and 2022 in °C/decade and its linear trend, from monthly UAH 6.0 satellite temperature data.

 

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better to know...?, climate-debate

Russian Temperature Records Are Not Cooperating With The CO2-Driven Climate Narrative

by K. Richard, Nov 14, 2022 in NoTricksZone

Two new studies indicate there has been no modern warming in the last centuries in western (Urals) and eastern (Kolyma) Russian mountain ranges.

A new 27,000-year temperature reconstruction assesses it was ~2.5 to 4.8°C warmer than today from 8.9-5.2 ka BP in the Ural Mountains, or when CO2 is said to have hovered in the 265 ppm range.

Summer temperatures were also warmer during the Medieval Warm Period, or from 1.2-0.7 ka BP. After a post-Medieval cool-down fostering in the Little Ice Age, the reconstructed record suggests there has been no warming since 0.5 cal ka BP, or for the last several centuries.

The smoothed temperature record shown in the study indicates there was only one brief period in the last 10,000 years that was not warmer than today.

“The reconstructed TJuly [8.9-5.2 cal ka BP] are the highest recorded, reaching up to 4.8 °C higher than today’s air temperature. … Present day T July have persisted since 0.5 cal ka BP.”

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unclassified

Let’s Talk About Real Climate Cataclysms

by P. Driessen, Oct 26, 2022 in ClimateChangeDispatch

The climate crisis! Save our planet! Stop using fossil fuels! The ranting never ends.

Present data show that hurricane frequency and intensity are not increasing, and tornado activity has declined significantly since 1975.

Offer clear evidence of past, recurring major climate changes, including a widespread Little Ice Age from 1300 to 1850, a 2,400-year-old forest emerging from beneath a melting Alaskan glacier, a 5,200-year-old mummified traveler frozen on a once-nearly-ice-free Italian Alps trail – and they respond, Shut up! The climate crisis! The science is settled! Stop using fossil fuels! [bold, links added]

Fine. But take a few minutes to ponder REAL climate disasters: the Pleistocene Ice Ages.

And then ask Michael Mann, Al Gore, John Kerry, and the rest of the climate cataclysm cabal to explain exactly how carbon dioxide and a few other greenhouse gases caused those massive ice sheets to grow and melt, multiple times. Just CO2 and GHG, all by themselves. They can’t do it. The CO2-driven crisis is a fable.

Widespread glaciation began some 1,800,000 years ago in North America and Europe, and about 800,000 years earlier on other continents. There were at least four, possibly five, major glacial periods, interspersed with warm intervals (like the one we’re in now) during which the glaciers mostly melted.

That last glacial epoch is named the Wisconsinan because some of the most exemplary features are in my home state. It marks the furthest extent of glaciers southward into the United States and east and west across Canada.

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https://www.steynonline.com/12856/a-sennight-of-steyn-september-25-october-1
<www.generalistjournal.com>
Book: ‘The Deliberate Corruption of Climate Science’
Book: ‘Human Caused Global Warming, the Biggest Deception in History’
https://www.technocracy.news/dr-tim-ball-on-climate-lies-wrapped-in-deception-smothered-with-delusion/
https://www.youtube.com/watch?v=tPzpPXuASY
https://www.technocracy.news/tim-ball-the-evidence-proves-that-co2-is-not-a-greenhouse-gas
https://www.youtube.com/watch?v=qOEFQDcT_lM

climate and geology

Another Study Says Europe Was At Times Warmer During The Last Glacial When CO2 Levels Were 40% Lower

by K. Richard, Oct 24, 2022 in NoTricksZone

The Earth was still in ice age conditions 14,700 to 12,900 years ago, or during the “Bolling interstadial.” CO2 hovered near 230 ppm at that time, and yet “continental Europe was a few degrees warmer than present” (Toth et al., 2022).

In recent years there have been multiple studies detailing a European climate that was as warm or warmer than today during the late Pleistocene ice age.

The latest study, Toth et al., 2022, uses chironomid proxy evidence to reconstruct summer temperatures at a lake site in the Eastern Carpathians.

These authors report that “continental Europe was a few degrees warmer than present during the Bolling interstadial,” and there were slightly (0.5°C) warmer-than-today periods (e.g., ~16,300 years ago) at the study site. The warming events were both pronounced (5°C) and abrupt.

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unclassified

Report: The Earth Has A Changing Climate, Not A Climate Crisis

by W. Manheimer, Sep 19, 2022 in ClimateChangeDispatch

The following excerpt is taken from:

Journal of Sustainable Development; Vol. 15, No. 5; 2022
ISSN 1913-9063 E-ISSN 1913-9071
Published by the Canadian Center of Science and Education

Abstract
The emphasis on a false climate crisis is becoming a tragedy for modern civilization, which depends on reliable, economic, and environmentally viable energy. [bold, links added]

The windmills, solar panels, and backup batteries have none of these qualities. This falsehood is pushed by a powerful lobby which Bjorn Lomborg has called a climate industrial complex, comprising some scientists, most media, industrialists, and legislators.

It has somehow managed to convince many that CO2 in the atmosphere, a gas necessary for life on earth, one which we exhale with every breath, is an environmental poison. Multiple scientific theories and measurements show that there is no climate crisis.

Radiation forcing calculations by both skeptics and believers show that the carbon dioxide radiation forcing is about 0.3% of the incident radiation, far less than other effects on climate.

Over the period of human civilization, the temperature has oscillated between quite a few warm and cold periods, with many of the warm periods being warmer than today.

During geological times, it and the carbon dioxide levels have been all over the place with no correlation between them.

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better to know...?, climate-debate

Europe wildfires: Are they linked to climate change?–NO!!!

by P. Homewood, Aug 15, 2022 in NotaLotofPeopleKnowThat

The BBC would like you to think so, with statements like these:

So far this year, the amount of land burnt by fires across the European Union is more than three times greater than what you would expect by the middle of July.

Almost 346,000 hectares (1,370 sq miles) of land have been recorded as burnt (as of 16 July), according to the European Forest Fire Information System (EFFIS).

Much of Western Europe has been hit by a record-breaking heatwave, which substantially increases the risk of fires….

“Heatwaves and droughts are exacerbated by climate change and are absolutely the defining factor in years with massive wildfire outbreaks, like the present one,” Dr Jones says….

“But we definitely see trends in fire weather risk because of climate change.

“The risk is higher in the Mediterranean region than the rest of Europe.”

Studies show increasing fire risk for central and southern regions of Europe over the past couple of decades.

Yet tucked away in the same article is this graph which proves all of these have no basis in fact:

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climate-debate

German Physicist: Human CO2 Emissions Responsible For 0.05°C Of The Global Warming Since 1750

by H. Harde, June 20,2022 in NoTricksZone

Professor Herman Harde, an environmental physicist, has authored a new position paper on the follies of assuming humans significantly impact the climate.

As detailed in his 2017 paper, Dr. Harde concludes the “anthropogenic contribution to the actual CO2 concentration is found to be 4.3% [a figure derived from IPCC AR5], its fraction to the CO2 increase over the Industrial Era is 15% and the average residence time 4 years.”

The IPCC overestimates the thermal effect of doubling CO2 by a factor of 5, as the consequent surface air temperature increase for a 120 ppm increase in CO2 is less than 0.3°C.

“Since only about 15% of the global CO2 increase is of anthropogenic origin, just 15% of 0.3°C, i.e., less than 0.05°C remains, which can be attributed to humans in the overall balance.”

“Changes of our climate can be traced back to natural interaction processes that exceed our human influence by orders of magnitude.”

climate-debate

Radiosonde Temps Show Northern Hemisphere, Tropical Warming Has Mostly Paused Since 1998

by K. Richard, May 22, 2022 in NoTricksZone

A new study indicates nearly all the Northern Hemisphere and Tropical warming in the last 40 years occurred by the late 1990s.

CO2 has risen by about 50 ppm since 1998 (367 to 418 ppm).

Interestingly, upper-air measurements of temperature from balloon-borne sensor radiosonde data, shown below in the image from a new study (Madonna et al., 2022), suggest there was more warming from the early 1980s to late 1990s – when CO2 only rose about 25 ppm (341 to 367 ppm) – than there has been this century.

Radiosonde measurements appear to depict mostly flat temperatures trends since 1998 in both the Northern Hemisphere (25°N to 70°N) and tropics (25°S to 25°N).

 

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Image Source: Madonna et al., 2022

 

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biology+acidification, climate-debate

Past global photosynthesis reacted quickly to more carbon in the air

by University of Copenhagen, Mar 10, 2022 in ScienceDaily

Ice cores allow climate researchers to look 800,000 years back in time: atmospheric carbon acts as fertilizer, increasing biological production. The mechanism removes carbon from the air and thereby dampens the acceleration in global warming.

Even under ice age conditions will plants, plankton, and other life forms be able to increase production whenever atmospheric carbon concentrations rise. The mechanism will not prevent an ongoing trend of global warming, but at least dampen the acceleration. This conclusion stems from an international collaboration involving the Physics of Ice Climate Earth (PICE) center of Niels Bohr Institute, University of Copenhagen.

“Global biosphere production through photosynthesis is the strongest absorbing flux of atmospheric carbon dioxide. It is therefore essential to understand its natural variability for a better projection of the future carbon cycle,” says Postdoc researcher Ji-Woong Yang, PICE, continuing:

“Nowadays, as we have Earth observation satellites and other advanced equipment, the mechanism of carbon fertilization is well established. However, we were not sure that the same mechanism existed in past periods where the climate was very different and atmospheric carbon concentrations much lower. The new results confirm the existence of the strong correlation and allow us to model future developments with more confidence.”

Eight glacial cycles are covered

In collaboration with Laboratoire des Science du Climat et de l’Environnement, France, the PICE team has studied the ancient air trapped inside tiny air bubbles in an Antarctic ice core. The ice core represents the last 800,000 years of climatic development.

The scientists take advantage of the fact that the oxygen atom does not only exist in the most common form 16O with 8 protons and 8 neutrons but also as the isotopes 17O and 18O. The isotopic composition is a tracer for biosphere productivity. Uniquely, the method will show the global level of biological production in contrast to other methods which give more localized results.

Combining the air bubble measurements with modeling of oxygen behavior in both the biosphere and the stratosphere, the researchers were able to quantify the biosphere productivity evolution under both glacial periods (ice ages) and interglacial periods. In total, eight glacial cycles were covered.

“The results clearly demonstrate that productivity drops during glacial periods and increases during interglacial periods. Further, a strong correlation exists with past atmospheric carbon dioxide concentrations measured from multiple ice cores. In addition, the effect is more prominent during glacial periods where the level of carbon dioxide and the global biosphere productivity start to increase several thousand years before the ice caps begin to melt. This correlation is explained by the strong fertilization effect by atmospheric carbon dioxide,” says Ji-Woong Yang.

climate-debate

Another dot on the graphs (Part II)

by Gavin, Feb 2, 2020 in RealClimate

We have now updated the model-observations comparison page for the 2021 SAT and MSU TMT datasets. Mostly this is just ‘another dot on the graphs’ but we have made a couple of updates of note. First, we have updated the observational products to their latest versions (i.e. HadCRUT5, NOAA-STAR 4.1 etc.), though we are still using NOAA’s GlobalTemp v5 – the Interim version will be available later this year. Secondly, we have added a comparison of the observations to the new CMIP6 model ensemble.

As we’ve discussed previously, the CMIP6 ensemble contains a dozen models (out of ~50) with climate sensitivities that are outside the CMIP5 range, and beyond the very likely constraints from the observations. This suggests that comparisons to the observations should be weighted in some way. One reasonable option is to follow the work of Tokarska et al (2020) and others, and restrict the comparison to those models that have a transient climate response (TCR) that is consistent with observations. The likely range of TCR is 1.4ºC to 2.2ºC according to IPCC AR6, and so we plot both the mean and 95% spread over all all models (1 ensemble member per model) (grey) and the TCR-screened subset (pink).

CMIP6 model means and spreads since 1979 (reader friendly version).

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climate and geology

Climate Change in the Early Holocene

by University of Oxford, Jan 27, 2022 in WUWT

Radiocarbon dating from a prehistoric cemetery in Northern Russia reveals human stress caused by a global cooling event 8,200 years ago Early hunter gatherers developed more complex social systems and, unusually, a large cemetery when faced by climate

Peer-Reviewed Publication

 

16:00 (GMT), Thursday 27 January 2022

Climate change in the Early Holocene

  • Radiocarbon dating from a prehistoric cemetery in Northern Russia reveals human stress caused by a global cooling event 8,200 years ago
  • Early hunter gatherers developed more complex social systems and, unusually, a large cemetery when faced by climate change

New insight into how our early ancestors dealt with major shifts in climate is revealed in research,  published today [27 Jan] in Nature Ecology & Evolution, by an international team, led by Professor Rick Schulting from Oxford University’s School of Archaeology.

It reveals, new radiocarbon dates show the large Early Holocene cemetery of Yuzhniy Oleniy Ostrov, at Lake Onega, some 500 miles north of Moscow, previously thought to have been in use for many centuries, was, in fact, used for only one to two centuries. Moreover, this seems to be in response to a period of climate stress.

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better to know...?, climate-debate

Using A Reference Period Outdated 30 Years, Germany’s DWD Weather Service Turns Cooling Into Warming

by Prof. F. Vahrenholt, Jan 8, 2022 in NoTricksZone

Globally, the deviation of the global mean temperature of the satellite-based measurements from the mean of period 1991-2020 rose slightly in December to 0.21 degrees Celsius. The mean temperature increase since satellite measurements began was 0.14 degrees Celsius per decade. The year 2021 was an average year compared to 2010 to 2020, with 0.134 degrees deviation from the thirty-year average. Six years since 2010 were warmer and 5 years were colder.

This is also true for Germany. But the German weather service gives a different impression

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How the German DWD Weather Service turned cooling into warming in 2021  

In its press release on Germany’s weather in 2021, the German Weather Service writes: “The mean temperature [Germany] in 2021 was 9.1 degrees Celsius (°C), 0.9 degrees above the value of the internationally valid reference period 1961 to 1990. 2021 was thus the eleventh year in a row that was too warm.”

Why does the DWD use the internationally no longer valid 1961-1990 reference period? It writes itself elsewhere: “To record the climate and its changes, mean values are formed over a period of 30 years…With the end of the year 2020, the reference period for current climatological assessments was replaced by the 1991 to 2020 period.”

Fudging with the reference period

The DWD thus followed the World Meteorological Organization (WMO)recommendation. But in the press release, the DWD still prefers to use the old, outdated period. The 1991 to 202 0reference period differs from the one of 1961 to 1990 by 1.1 degrees. So the DWD should have written : “2021 was 9.1 degrees, 1.3 degrees cooler than 2020 and even -0.2 degrees Celsius below the average from 1991 to 2020. Since 1991 there have only been 9 years colder than 2021.”

But 0.9 degrees more and the eleventh year in a row that is too warm (compared to the colder period of 1961-1990) of course fits much better with the zeitgeist.

Read original in German at Die kalte Sonne. 

climate-debate

New Study: A ‘Profound’ ~1°C Cooling Trend Across East Antarctica Since 1979 Is ‘Likely To Accelerate’

by K. Richard, July 12, 2021 in NoTricksZone

Except for a few pockets of warming along the West Antarctic coast, surface air temperatures have cooled profoundly across East Antarctica – most of the continent, as well as the surrounding Southern Ocean – in the last 40 years (1979-2018). About 30% of the cooling can be explained by Madden-Julian Oscillation forcing.

Atmospheric CO2 concentrations rose from 337 ppm in 1979 to 408 ppm in 2018.

But according to graphical illustrations of surface air temperature (SAT) trends from satellite observations documented in a new study (Hsu et al., 2021), nearly the entire continent of Antarctica and much of the surrounding Southern Ocean have undergone about -0.02°C/year (-0.2°C per decade) SAT cooling during this period.

East Antarctica’s temperatures have fallen by about 1°C in the last 40 years, with approximately -0.4°C cooling from 1999-2018 relative to 1979-1998.

Per the authors, one-third of this 40-year cooling trend can be attributed to Madden-Julian Oscillation (MJO) forcing. The MJO influence is “likely to accelerate” the long-term cooling trend for East Antarctica in the coming decades.

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better to know...?, climate-debate

Eastern Alps may have been ice-free in the time of Ötzi the Iceman

by C. Rotter, Dec 21, 2020 in WUWT

From The New Scientist

Glaciers in the Ötztal Alps in Austria are currently melting and may be lost within two decades, but this might not be the first time humans have seen this kind of change. A new analysis reveals that glaciers in this region formed just before or perhaps even within the lifetime of Ötzi the Iceman, a mummified body found just 12 kilometres away in 1991.

Pascal Bohleber at the Austrian Academy of Sciences in Vienna and his colleagues drilled 11 metres into the Weißseespitze summit glacier, down to the bedrock, at 3500 metres altitude and collected two ice cores. They then used radiocarbon dating to  analyse microscopic bits of organic material extracted from the ice cores and found that the glacier is 5200 to 6600 years old. Ötzi is thought to have lived between 5100 and 5300 years ago, and his body was found preserved in ice.

The glacier’s age means it formed during a time called the mid-Holocene warm period, when Earth’s climate was warmer than it is now. It is also dome-shaped, which Bohleber says is rare in the Alps and means that the ice has seen very little movement over time, meaning we can use it to study the climate when it formed.

Read more: Ötzi the Iceman’s last journey revealed by moss found in his stomach

“More information on the mid-Holocene warm period, when the glaciers were smaller than today, is direly needed so that we can better predict how the glaciers will respond to the anticipated future climate over the next 50 years,” says Bethan Davies at Royal Holloway, University of London.

Comparing ice cores from different sites tells us quite a bit about the past climate in that region, says Bohleber, but that gets harder as the glaciers thaw. Meltwater makes it more difficult to drill for ice cores and causes the glaciers to slide downhill, exposing the ancient ice to modern contaminants.

Read more: https://www.newscientist.com/article/2263399-eastern-alps-may-have-been-ice-free-in-the-time-of-otzi-the-iceman/#ixzz6hDkuLfkW

See also  in GWPF

better to know...?, climate-debate

New sunspot cycle could be one of the strongest on record, new research predicts

by National Center for Atmospheric Research/University Corporation for Atmospheric Research, Dec 7, 2020 in ScienceDaily

In direct contradiction to the official forecast, a team of scientists led by the National Center for Atmospheric Research (NCAR) is predicting that the Sunspot Cycle that started this fall could be one of the strongest since record-keeping began.

In a new article published in Solar Physics, the research team predicts that Sunspot Cycle 25 will peak with a maximum sunspot number somewhere between approximately 210 and 260, which would put the new cycle in the company of the top few ever observed.

The cycle that just ended, Sunspot Cycle 24, peaked with a sunspot number of 116, and the consensus forecast from a panel of experts convened by the National Aeronautics and Space Administration (NASA) and the National Oceanic and Atmospheric Administration (NOAA) is predicting that Sunspot Cycle 25 will be similarly weak. The panel predicts a peak sunspot number of 115.

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better to know...?, climate and geology

New Paleoclimatology Finding Shows Earth’s Climate Was Typically Warmer than Today

by H.S. Sterling, Dec2, 2020 in WUWT

Archaeologists have published a new paper in The Holocene, DOI: 10.1177/0959683620972775 that confirms what previous research has shown: numerous periods during recent history have been as warm as or warmer than the present.

The press release was covered in The New Scientist, “Climate change has revealed a huge haul of ancient arrows in Norway,”  and discusses the findings of researchers from the Universities of Cambridge, Oslo, and Bergen. The researchers discovered a “treasure trove” of arrows, arrowheads, clothing, and other artifacts, recently uncovered by a receding ice in a mountainous region of southern Norway. The oldest arrows and artifacts date from around 4100 BC. The youngest artifacts date from approximately AD 1300, at the end of the Medieval Warm Period. Because present temperatures are only now exposing some of the artifacts were deposited when no ice covered the ground, temperatures were clearly warmer during the many periods when artifacts were deposited.

Along with the arrows and other artifacts, the researchers found nearly 300 specimens of reindeer antler and bone exposed by receding ice. Because reindeer presently frequent the area, the archaeologists say they are confident the area has served as an important hunting ground, off and on, for millennia.

The fact that artifacts were found from several different periods separated by hundreds and thousands of years in time indicates the ice and snow in the region has expanded and receded several times over the current interglacial period.

Elsewhere in Norway, scientists also recently uncovered what they have labeled a “Viking highway,” a route the ancient peoples inhabiting the region used to travel regularly. The route had for approximately 2,000 years been covered by snow and ice that expanded as the region’s climate shifted from a relatively warm period, comparable to present temperatures, to a colder period during which “permanent” thick snow and ice cover formed. This erected the equivalent of a “highway closed” sign.

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climate and geology, climate-debate

How ancient dust from the sea floor helps to explain climate history

by UNIVERSITY OF OLDENBURG, Nov 11, 2020 in WUWT

During the last Ice Age about 20,000 years ago, iron-containing dust acted as a fertilizer for marine phytoplankton in the South Pacific, promoting CO2 sequestration and thus the glacial cooling of the Earth. But where did the dust come from? Researchers led by Dr. Torben Struve, geoscientist at the University of Oldenburg, Germany, have investigated this open question of climate history, which is also relevant with respect to current climate change.

Using sediment cores from the sea floor, they found that a large part of the dust deposited in the southern South Pacific at that time had travelled an extremely long way. Up to 80 percent of the dust came from what is now north-west Argentina, from where it was transported almost completely around the globe by the prevailing westerly winds. After a voyage of up to 20,000 kilometres, it contributed significantly to the increased input of iron into the glacial South Pacific. The dust input from Australia, which dominates in the South Pacific today, played only a minor role. The research team has published these new insights into the mechanisms of natural iron input into the Southern Ocean in the journal Nature Communications.

“We have analysed the chemical fingerprint of the dust and compared it with geological data from several continents. This was laborious work, like a jigsaw puzzle,” says Struve, a post-doctoral scientist in the research group “Marine Isotope Geochemistry” at the University’s Institute for Chemistry and Biology of the Marine Environment (ICBM). The team included researchers from his group as well as colleagues from the Alfred Wegener Institute – Helmholtz Centre for Polar and Marine Research, Bremerhaven (Germany), and from Columbia University, New York (USA).

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climate and geology

Study: Ancient ocean oxygen levels associated with changing atmospheric carbon dioxide

by Texas A&M University, May 24, 2020 in WUWT

A Texas A&M-led study analyzed ocean floor sediment cores to provide new insights into the relationship between deep ocean oxygenation and atmospheric carbon dioxide levels in the 50,000 years before the last ice age

IMAGE: Deep ocean floor sediment cores hold chemical clues to Earth’s past. view more  Credit: Texas A&M University

Why do carbon dioxide levels in the atmosphere wax and wane in conjunction with the warm and cold periods of Earth’s past? Scientists have been trying to answer this question for many years, and thanks to chemical clues left in sediment cores extracted from deep in the ocean floor, they are starting to put together the pieces of that puzzle.

Recent research suggests that there was enhanced storage of respired carbon in the deep ocean when levels of atmospheric carbon dioxide concentrations were lower than today’s levels. But new research led by a Texas A&M University scientist has reached back even further, for the first time revealing insights into atmospheric carbon dioxide levels in the 50,000 years before the last ice age.

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climate-debate

New Study: A Massive Cooling Of 2°C In 8 Years (2008-2016) Has Jolted Large Regions Of The North Atlantic

by K. Richard, February 14, 2020 in NoTricksZone

From 2008 to 2016 a widespread cooling ranging from 0.6°C to more than 2.0°C has chilled effectively the entire oceanic region from E. Canada to N. Iceland to S. Europe. The cooling persists year-round and extends from the surface down to depths of 800 m.

 

Image Source: Bryden et al., 2020

A year ago scientists revealed a large swath of the North Atlantic surface had cooled at a rate of -0.78°C per decade between 2004 and 2017 (Fröb et al., 2019).

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