When the global climate has the hiccups – ‘repeated rapid increases in temperature’

Promoters of a current ‘climate crisis’ often call modern warming and/or events within it, ‘unprecedented’. However, compared to events like this: “A Neanderthal would have experienced increases in the average temperature of several degrees over the course of their life” [explains Prof.], not much is presently going on. Climate variability can happen in different ways, and repeat over long timescales.
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In recent geological history, the so-called Quaternary period, there have been repeated ice ages and warm periods, says Science Daily.

Researchers are able to determine past climate variability from the composition of climate records. In the case of the last glacial period 100,000 years ago, ice cores from Greenland in particular provide researchers with detailed data.

For example, Greenland ice cores show that there were repeated rapid increases in temperature.

“We are talking about increases of 5 to 10 degrees within 30 to 40 years on average in the case of Europe. A Neanderthal would have experienced increases in the average temperature of several degrees over the course of their life,” explains Prof. Dominik Fleitmann, Professor of Quaternary Geology at the University of Basel.

He calls the phenomena “climate hiccups.”

These Dansgaard-Oeschger events are well documented for the last glacial period, but the climate records from Greenland only cover the last 120,000 years.

It was therefore previously unknown whether these Dansgaard-Oeschger events also occurred during the penultimate glacial period 135,000 to 190,000 years ago.

Frederick Held, a PhD candidate in Fleitmann’s research group, was able to show that Dansgaard-Oeschger events also occurred during the penultimate glacial period using isotopic measurements on stalagmites.

He is the lead author of the study which was published in the scientific journal Nature Communications.

The North Atlantic as the source of change

The stalagmites examined originate from the Sofular Cave in Turkey, which is located in a region that is very sensitive to climate change.

The researchers therefore refer to it as a key region, as it is influenced by the winds of the North Atlantic and the Black Sea is just a few kilometers away.

“We used the isotopic composition in the stalagmites to determine the moisture sources from which they are formed — the Black Sea, the Mediterranean Sea and the North Atlantic,” explains Frederick Held.

For the first time, the evaluations carried out on the stalagmites from the Sofular Cave have proven that Dansgaard-Oeschger events also occurred during the penultimate glacial period.

“It was previously unknown whether these relatively brief temperature events actually happened in earlier glacial periods,” states Held.

However, they occurred less frequently in the penultimate glacial period than in the last one: “The temperature peaks are twice as far apart from one another, meaning there were longer cold phases between them.”

These temperature fluctuations originate in the North Atlantic, as the circulation of the ocean is a global conveyor belt for heat and can sometimes be stronger and sometimes weaker.

“For example, the circulation affects the exchange of heat between the atmosphere and the ocean, which, in turn, impacts the balance of heat in the Northern Hemisphere and air flows and rainfall,” explains Held.

He states that weakened circulation also reduces the quantity of CO2 which the ocean absorbs from the atmosphere.

These ocean currents were different in the penultimate glacial period than in the last one, which explains the different intervals between the Dansgaard-Oeschger events.

This shows that not all glacial periods are the same and not all warm periods are the same.
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The geologist also hopes to clarify any outstanding questions by means of additional analyses. “For example, we do not yet know whether the increases in temperature were periodic or stochastic, in other words random.”

Full article here.

Image: Greenland ice core [credit: K. Makinson @ Wikipedia]

Is Iceland entering a new volcanic era?

Scientists think there’s some evidence of a centuries-long periodic pattern or cycle, but aren’t sure what it is or what determines the length of it. The graphic shows the most recent two of the five marked phases are west of the earlier ones, plus some apparent north-east to south-west alignments, but otherwise it’s open to intepretation.
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This week, Iceland woke up to yet another day of fire, as towering fountains of lava lit up the dark morning sky, says BBC News.

This time the evacuated town of Grindavik was spared, but the molten rock still wrought havoc – engulfing a pipe that provides heat and hot water to thousands living in the area and cutting off a road to the Blue Lagoon tourist attraction.

It is the third short-lived eruption on the Reykjanes peninsula since December 2023 and the sixth since 2021. But scientists think this is just the start of a period of volcanic activity that could last for decades or even centuries.

So what is going on?

Oldie but Goldie: Climategate: how the conspirators gagged on their deceptions

Andrew Bolt Herald Sun Dec 6 2009

I’ve wondered whether Climategate scientist Tom Wigley, an Australian, finally choked on all the fraud, fiddling and coverups he was witnessing from fellow members of his Climategate cabal. Steven Hayward points out that many other Climategate scientists privately had trouble swallowing the practices of their colleagues:

In 1998 three scientists from American universities–Michael Mann, Raymond Bradley, and Malcolm Hughes–unveiled in Nature magazine what was regarded as a signal breakthrough in paleoclimatology–the now notorious “hockey stick” temperature reconstruction (picture a flat “handle” extending from the year 1000 to roughly 1900, and a sharply upsloping “blade” from 1900 to 2000). Their paper purported to prove that current global temperatures are the highest in the last thousand years by a large margin–far outside the range of natural variability. The medieval warm period (MWP) and the little ice (LIA) age both disappeared.

The Sahara Desert used to be a green savannah : Research explains why – it’s a climate cycle

Sahara desert from space [image credit: NASA]

We’re informed that ‘scientists have identified more than 230 of these greenings occurring about every 21,000 years over the past eight million years.’ (Ice ages may account for the numerical shortfall). Climate models aren't able to simulate these greenings, or at least not their magnitude. The period they identify is the combined precession cycle, i.e. the beat period of the tropical and anomalistic orbits (years) of the Earth (when the difference between the number of each reaches 1). Inevitably it’s about the energy received from the Sun.
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Algeria’s Tassili N’Ajjer plateau is Africa’s largest national park, says The Conversation (via Phys.org).

Among its vast sandstone formations is perhaps the world’s largest art museum. Over 15,000 etchings and paintings are exhibited there, some as much as 11,000 years old according to scientific dating techniques, representing a unique ethnological and climatological record of the region.

Curiously, however, these images do not depict the arid, barren landscape that is present in the Tassili N’Ajjer today.

600 years of tree rings reveal climate variability in California, droughts and floods more severe and longer lasting than in the modern record

California’s San Joaquin Valley and Central Valley [image credit: Mark Miller @ Wikipedia]

The region studied has a naturally varying climate, as do most regions of the world. One minute the article says the last few centuries there had more weather extremes than now, the next it implies the future could or will be like that again or worse, due to being ‘compounded’ by the catch-all *climate change*. File under ‘unconvincing’?
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The San Joaquin Valley in California has experienced vast variability in climate extremes, with droughts and floods that were more severe and lasted longer than what has been seen in the modern record, according to a new study of 600 years of tree rings from the valley, says Eurekalert.

The researchers used the tree rings to reconstruct plausible daily records of weather and streamflow scenarios during the 600-year period.

This new approach, combining paleo information with synthetic weather generation, may help policymakers and scientists better understand – and anticipate – California’s flood and drought risks and how they will be compounded by climate change. [Talkshop comment – unsupported assertion].

The group’s paper is published in Earth’s Future, a journal of the American Geophysical Union.

‘Time’s finally up’: Impending Iceland eruption is part of centuries-long volcanic pulse

Lava fields of the Reykjanes Peninsula [image credit: Vincent van Zeijst @ Wikipedia]

The headline obviously raises the question of the origin of such a pulse and of its suggested frequency. On the other hand a damp squib (from a spectator point of view) can’t be ruled out entirely at this stage, although some of the cracks already appearing on the surface do look quite large and other signs are ominous.
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Iceland’s potentially imminent eruption in the Reykjanes Peninsula is part of a 1,000-year cycle of volcanic activity that will likely cause eruptions for centuries, scientists say.

“Time’s finally up,” Edward W. Marshall, a researcher at the University of Iceland’s Nordic Volcanological Center, told LiveScience in an email. “We can get ready for another few hundred years of eruptions on the Reykjanes.”

Seismic activity began increasing in the south of the peninsula in October, with hundreds of earthquakes recorded there each day. On Nov. 10, authorities evacuated the town of Grindavík, with experts warning a volcanic eruption could take place in just days.

Norwegian archaeologists are salvaging priceless artifacts from melting glaciers—why were they found there?

Innlandet county, Norway [credit: NordNordWest @ Wikipedia]

An earlier article, featured here at the Talkshop said ‘artifacts have come to light thanks to a warming climate, proving that a mountain pass served as an important trade network’. We’re told ‘The pass was in use between the years 300 and 1500 AD, and most active around the year 1000. Its use declined with the Little Ice Age, around 1300, and the Black Death, around 1400.’ All of which suggests it was a popular route when conditions were warm enough. Of course any warmth back then that was similar to today can’t be ascribed to the non-natural causes claimed by climate alarmists as the only explanation for the current conditions. But they don’t address that issue.
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There is surely little upside to the environmental changes posed by global warming [Talkshop comment – standard doomster-speak], but nevertheless, a group of Norwegian archaeologists is seizing the opportunities presented by the country’s rapidly melting glaciers, says Artnet News.

That group is Glacier Archaeology Program—snappy internet alias: Secrets of the Ice—and since receiving permanent government funding in 2011 it has been responsible for 90 percent of Norway’s glacial finds.

Granted, the group’s success is partly tied to the topography of Innlandet. The county boasts many of Norway’s highest peaks, and the team has pursued salvaging artefacts from remote locations in a comprehensive and systematic manner. To date, it has made 4,000 finds across 66 sites.

Open peer review: The truth about weather extremes: What the past tells us – The GWPF

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We are keen to receive review comments for our new report which is now available for open review here, says The Global Warming Policy Foundation.

Ralph Alexander: The truth about weather extremes. What the past tells us

This report refutes the popular but mistaken belief that today’s weather extremes are more common and more intense because of climate change, by examining the history of extreme weather events over the past century or so.

Drawing on newspaper archives, the report presents multiple examples of past extremes that matched or exceeded anything experienced in the present-day world.

Pyrenean caves reveal a warmer past – Net Zero Watch

Pyrenees view

The finding that ‘the temperature increase [since 1950] is most notable in the past 2500 years’ fits with the recent research of Prof. Harald Yndestad (as we featured here). Natural climate variation never went away.
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The world’s high mountain regions are particularly sensitive to climate change, says Dr David Whitehouse @ Net Zero Watch.

Straddling the border between France and Spain the Pyrenees occupy a crucial position in southern Europe, influenced by both Mediterranean and Atlantic climates.

New research published in the journal ‘Climate of the Past,’ investigating climate proxy data based on stalagmites is revealing that past climates were warmer than our own.

Study attributes Tibetan Empire collapse in 9th century to climate change

Historical reconstruction of the Tibetan Empire’s extent among surrounding empires at its peak ca. 800 CE [Credit: Chen et al. 2023]

The ‘abrupt’ climate change found by the researchers looks like a prelude to the Medieval Warm Period. Even without examining any technical details it’s clear from the data that the climate of the region did change. Interestingly, the aftermath of the period of change looks a lot like the Medieval Warm Period (see here, under ‘severe dry and warm’), which Wikipedia thinks ‘was a time of warm climate in the North Atlantic region that lasted from c. 950 to c. 1250’. The North Atlantic and Tibet are far apart, obviously.
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The Tibetan Empire was the world’s highest elevation empire, sitting over 4,000m above sea level, and thrived during 618 to 877 CE, says Phys.org.

Home to an estimated 10 million people, it spanned approximately 4.6 million km² across East and Central Asia, extending into northern India.

Considering the hostile conditions for populations to expand, including hypoxia where oxygen concentrations are 40% lower than at sea level, it is incredible that the empire flourished.

However, its collapse in the 9th century is not fully understood, with new research published in Quaternary Science Reviews aiming to untangle the role climate may have played in the end of a great civilization.

The biggest myth about fossil fuels and dinosaurs, debunked by science

Credit: fuelfix.com

In case you weren’t quite sure…
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Is your car really powered by dinosaurs? – asks BBC Science Focus.

Most oil reserves were formed between 65 and 252 million years ago. While this does overlap with the ‘dinosaur times’, oil is a marine sediment made of the remains of algae and plankton.

Skeletons of prehistoric reptiles such as plesiosaurs and ichthyosaurs (neither of which count as dinosaurs) have been found in the same geological layers as oil and they may have contaminated the oil deposit.

New study reveals abrupt shift in tropical Pacific climate during Little Ice Age

Earth and climate – an ongoing controversy

Evidence that what is today called ‘climate change’ can naturally occur, and has occurred, over a relatively short timescale – described here as ‘remarkable’. Maybe history is trying to tell us future climate conditions are more unpredictable than advocates of IPCC doctrines would have us believe.
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An El Niño event has officially begun, says Science Daily.

The climate phenomenon, which originates in the tropical Pacific and occurs in intervals of a few years will shape weather across the planet for the next year or more and give rise to various climatic extremes.

El Niño-like conditions can also occur on longer time scales of decades or centuries. This has been shown to have occurred in the recent past by an international research team led by Ana Prohaska of the University of Copenhagen and Dirk Sachse of the German Research Centre for Geosciences (GFZ).

How Big was Carrington’s Sunspot?

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A 1967 group of sunspots ‘nearly led to nuclear war’.
https://www.space.com/33687-solar-storm-cold-war-false-alarm.html

Spaceweather.com

June 6, 2023: If you want to have a bit of fun with ChatGPT, ask it the following question: “How big was Carrington’s sunspot?”

ChatGPT’s response: “Richard Carrington’s observations of the great solar storm in 1859 did not provide a direct measurement of the size of the sunspot.”

Poor Richard Carrington must be turning in his grave. The astronomer made beautiful drawings of the sunspot, shown here in a figure from Carrington’s report in a 1859 issue of the Monthly Notices of the Royal Astronomical Society:

We definitely know how big it was.

In the mid-19th century, Carrington was known throughout England for his careful measurements of sunspots. Supported by his father’s beer-brewing business, he spent almost every cloudless day in London projecting an image of the sun through his telescope and drawing the sunspots he saw on the 11-inch solar disk. On Sept. 1st, 1859, one of them did…

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Summer sea ice disappearance from the Arctic has happened before, say researchers

They studied molecules from certain algae that are only produced when there is sea ice. Natural climate variation alone was all it took to reach the required temperature level.
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The “Last Ice Area” north of Greenland and Canada is the last sanctuary of all-year sea ice in this time of rising temperatures caused by climate change.

A new study now suggests that this may soon be over, says Phys.org.

Researchers from Aarhus University, in collaboration with Stockholm University and the United States Geological Survey, analyzed samples from the previously inaccessible region north of Greenland.

The sediment samples were collected from the seabed in the Lincoln Sea, part of the “Last Ice Area”. They showed that the sea ice in this region melted away during summer months around 10,000 years ago.

The research team concluded that summer sea ice melted at a time when temperatures were at a level that we are rapidly approaching again today.

New Model Explains The Water Cycles of Mars’s Swiss Cheese-Looking South Pole

Mars [image credit: NASA]

It’s said to be related to the current obliquity cycle period of about 100,000 years. Mystery solved?
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Seen from space, regions of Mars around the south pole have a bizarre, pitted “Swiss cheese” appearance, says ScienceAlert.

These formations come from alternating massive deposits of CO2 ice and water ice, similar to different layers of a cake.

For decades, planetary scientists wondered how this formation was possible, as it was long believed that this layering would not be stable for long periods of time.

Kill dates of black mosses are archives of Antarctic glacier history

Credit: coolantarctica.com

Natural climate variation is and always has been an ongoing process in Antarctica, just like everywhere else. Research suggests conditions similar to recent years prevailed about 850 years ago in at least one region.
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Mosses, one of the few types of plants living in Antarctica, have a tenuous existence, threatened by advancing glaciers, says the U.S. National Science Foundation.

When glaciers move, they can entomb or cover a plant — starving it of light and warmth. Scientists have discovered that the timing of when a glacier killed a moss, the kill date, provides an archive of glacier history.

The date the plant died coincides with the time the glacier advanced over that location. As glaciers recede, the previously entombed mosses are exposed, now dead and black.

Climate signals from ancient ice and wood

Hunger stone at Decin on the River Elbe, with dates back to 1616 or earlier [image credit: Norbert Kaiser @ Wikipedia]

We looked at some of this recently, here and here. Of course the problem nowadays is that weather news is liable to be subjected to the melodrama treatment by climate obsessives. Re. the European droughts, there’s also the evidence of the ‘hunger stones’, for example.
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The Holocene – the time since the end of the last glaciation – which has witnessed all of humanity’s recorded history and the rise and fall of civilisations – began only 11,700 years ago, says Dr David Whitehouse @ Net Zero Watch.

It is a relatively warm period, but how warm was it at its warmest?

What happened in the past informs current climate models placing the current global warming into perspective.

Elephant seal remains show Antarctic sea was warmer in the mid-to-late Holocene

Antarctica

Once again, evidence of times in the past long before the industrial era when warming similar to or in excess of the present ‘crisis’ conditions occurred in a polar region. Natural climate variation is the norm.
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Studying the response of Antarctic ice sheets to past warming episodes is essential to understand how they may respond to the present warming climate, as their melting and collapse can contribute to global sea level rise, says Phys.org.

Detailed records of past ocean temperatures close to the continent are rare, but clues to how ice sheets and sea ice responded to global conditions in the past can be found in funny places—even in the remains of animals that once lived there.

A study led by the University of Maine used the presence (and eventual lack thereof) of elephant seals to illustrate how the area transformed in a warm period in the recent past.

Climate models and the Holocene global temperature conundrum

Earth and climate – an ongoing controversy

Here we learn “our review revealed how surprisingly little we know about slow-moving climate variability”. In between unsupported assertions about human-caused modern warming, the authors of the review article ponder the realities of natural climate variability, including a warmer-than-today period in the Holocene, under the headings ‘What we know’, ‘What we don’t know’, and ‘Why it matters’. The closing line: “Our review suggests that climate models are underestimating important climate feedbacks that can amplify global warming.” Is this another way of saying long-term natural variation is being underestimated by the models?
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Accurate climate models play a critical role in climate science and policy, helping to inform policy- and decision-makers throughout the world as they consider ways to slow the deadly effects of a warming planet and to adapt to changes already in progress, says Eurekalert.

To test their accuracy, models are programmed to simulate past climate to see if they agree with the geologic evidence.

The model simulations can conflict with the evidence. How can we know which is correct?

A review article published today in Nature addresses this conflict between models and evidence, known as the Holocene global temperature conundrum.

Study finds three phases of glacier advance in Northern Antarctic Peninsula in the last 1,500 years

Credit: coolantarctica.com

Glaciers advance and retreat. Repeating cycles of natural climate variation exposed.
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Receding glaciers in the northern Antarctic Peninsula are uncovering and reexposing black moss that provides radiocarbon kill dates for the vegetation, a key clue to understanding the timing of past glacier advances in that region, says Phys.org.

A University of Wyoming researcher led a study that determined the black moss kill dates coincide with evidence of glacier advances from other studies that found such events occurred 1,300, 800 and 200 calibrated years prior to 1950.

“We used radiocarbon ages, or kill dates, of previously ice-entombed dead black mosses to reveal that glaciers advanced during three distinct phases in the northern Antarctic Peninsula over the past 1,500 years,” says Dulcinea Groff, a postdoctoral research associate in the UW Department of Geology and Geophysics.