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better to know...?, climate-debate

3 More New Drought And Temperature Reconstructions Do Not Support The Climate Alarm Narrative

by K. Richard, Jan 13, 2025 in NoTricksZone

Studies from Central China, Russia, and Central Europe indicate there was just as much (0r more) warming and drought prior to 1900, or when CO2 concentrations were under 300 ppm.

A new 1606 to 2016 Central China winter (minimum) temperature reconstruction (Jiang et al., 2024) reveals cold periods only occurred in 9 years of the 1600s (1663-1672), but there were 71 years of cold periods during the 20th century (1900-1942, 1959-1979, 1985-1994).

Notably, CO2 hovered around 278 ppm during the 1600s and 1700s, but it rose from 290 ppm to 370 ppm during the 1900s.

From 1650-1750 the winter temperatures in Central China were 0.44°C warmer than they were during the 20th century. The authors were surprised by this temperature result, as 1650-1750 falls within the timing of the Little Ice Age.

“Surprisingly, during 1650–1750, the lowest winter temperature within the research area was about 0.44 °C higher than that in the 20th century, which differs significantly from the concept of the ‘cooler’ Little Ice Age during this period. This result is validated by the temperature results reconstructed from other tree-ring data from nearby areas, confirming the credibility of the reconstruction.”

Finally, it should be noted that the year 1719 was 1.4°C warmer (-3.17°C) than the 1961-2016 average (-4.57°C).

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A new 1803-2020 Central Europe precipitation reconstruction (Nagavciuc et al., 2025) determines droughts were more prolonged and pronounced during the 1800s than in the 1900s, as the 1900s were relatively wet. Only one recent period (2007-2020) endured extreme drought, but it did not exceed the severity of the 1818–1835, 1845–1854, 1882–1890 drought years.

 

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climate and geology

Mystery Volcano’ that Lowered Global Temperatures Nearly 2 degrees Fahrenheit in 1831 Identified

by L. Eastman, Jan 5, 2025 in WUWT

Whenever I write about climate change, I often note that volcanoes can have significant impacts on the global climate.

A new example has been recently revealed, as a ‘mystery volcano’ that erupted in 1831 and significantly cooled Earth’s climate has finally been identified as Zavaritskii on Simushir Island, part of the Kuril Islands archipelago between Russia and Japan.

This eruption was one of the most powerful of the 19th century, releasing an enormous amount of sulfur dioxide into the stratosphere. The Earth-caused emissions resulted in a decrease of approximately one degree Celsius (1.8 degrees Fahrenheit) in the annual average temperatures of the Northern Hemisphere.

The challenge in locating the volcano was due to its remote location.

While the year of this historic eruption was known, the volcano’s location was not. Researchers recently solved that puzzle by sampling ice cores in Greenland, peering back in time through the cores’ layers to examine sulfur isotopes, grains of ash and tiny volcanic glass shards deposited between 1831 and 1834.

Using geochemistry, radioactive dating and computer modeling to map particles’ trajectories, the scientists linked the 1831 eruption to an island volcano in the northwest Pacific Ocean, they reported Monday in the journal Proceedings of the National Academy of Sciences.

..Before the scientists’ findings, Zavaritskii’s last known eruption was in 800 BC.

“For many of Earth’s volcanoes, particularly those in remote areas, we have a very poor understanding of their eruptive history,” said lead study author Dr. William Hutchison, a principal research fellow in the School of Earth and Environmental Sciences at the University of St. Andrews in the United Kingdom.

“Zavaritskii is located on an extremely remote island between Japan and Russia. No one lives there and historical records are limited to a handful of diaries from ships that passed these islands every few years,” Hutchison told CNN in an email.

To find the volcano, researchers compared the chemistry of microscopic shards of ash extracted from ice cores drilled in Greenland with samples from the Zavaritskii caldera. They determined it was a perfect match.

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better to know...?, climate-debate

Central Greenland Was Recently Ice-Free And Covered With Plants When CO2 Was Under 300 ppm

by K. Richard, Jan 3, 2025 in NoTricksZone

Today, with CO2 levels supposedly in the “dangerously high” range, Central Greenland has 3 kilometers of ice piled atop it.

Scientists have known since the GISP2 borehole was drilled in 1993 that Central Greenland deglaciated at least once in the late Pleistocene (Bierman et al., 2024). Indeed, the Summit of the modern Greenland ice sheet was actually ice-free at some point between 250,000 and 1.1 million years ago – which is relatively recent from a geological perspective.

Plants, wood, insects, fungi and other remnants suggestive of vegetation were recovered from the bottom of the boring site. This is quite a contrast to today’s 3000-meters-high ice sheet at this same location.

“The presence of poppy, spike-moss, fungal sclerotia, woody tissue, and insect parts in the GISP2 till shows that tundra vegetation once covered central Greenland, mandating that the island was largely ice-free.”

The atmospheric CO2 concentration is presumed to have ranged between 275 and 290 ppm during the Late Pleistocene, or during this same period when Greenland was ice-free. These sub-300 ppm CO2 levels are thought to be the same as they were from 1700 to 1900 (the Little Ice Age), when, as today, Central Greenland has remained buried in kilometers of ice.

The authors of this study use existing knowledge of Greenland’s climate (for example, Summit’s mean July temperature is -7°C) to calculate how much warmer Central Greenland was “when the ice was gone” during the last 1.1 million years. Controlling for lapse rate, Central Greenland’s average surface air temperatures were likely +3 to 7°C in July when it had no ice sheet.

The atmospheric CO2 concentration thus appears to be largely unrelated to either Greenland’s climate or its state of glaciation.

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climate-debate

New Study: Warming Trend Since 2013 From Increased Absorbed Solar Radiation, Not CO2

by K. Richard, Dec 26, 2024 in ClimateChangeDispatch

The 2013-2022 warming trend and the extreme warmth in 2023 were “not associated with” declining outgoing long-wave radiation induced by rising greenhouse gases. [emphasis, links added]

Instead, a new study published in the journal Science contends that decreasing cloud albedo and the consequent increase in ASR, or absorbed solar radiation (+0.97 to 1.10 W/m²/decade according to ERA5 and CERES, respectively) explains the warming over the last decade. (Less cloud cover means more solar radiation reaches the Earth’s surface, warming it.)

A rising trend in anthropogenic greenhouse gases was supposed to reduce the Earth’s outgoing long-wave radiation (OLR), and a declining OLR was thought to be the driver of modern warming.

Instead, the opposite has occurred. There has been an increasing OLR trend since 2013.

This enhancement of the Earth’s OLR trend actually serves to counteract the ASR-induced warming strongly associated with the aforementioned declining cloud cover albedo.

In other words, the total greenhouse effect impact from rising greenhouse gases has recently been contributing to a reduction in global warming, partially offsetting the warming induced by rising ASR.

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climate-debate

Climate Change over the past 4000 Years

by A. May, Dec4, 2024 in WUWT

I last wrote about Climate Change and Civilization for the past 4,000 Years in 2016. Since then, a lot has changed, and I’ve learned a lot more about the subject. First, we learned that various air and sea temperature proxies, such as ice core δ18O or tree rings, are all different. For a discussion of some temperature proxies used and the problems with them, see here. Proxies have different accuracies, they are often sensitive to the temperature of different seasons, and they have different temporal resolutions. Thus, as pointed out by Soon and Baliunas in 2003, they are all local and “cannot be combined into a hemispheric or global quantitative composite.”

The global average surface temperature (GAST) reconstruction relied upon in the IPCC AR6 report was by Kaufman, et al. The authors admit that the average spacing of each temperature (the temporal resolution) is 164 years. Thus, to compare the entire global instrumental temperature record to the proxies in a valid way, one must average all the daily readings since 1860 into one point. That is, the rate of warming since 1860 is irrelevant, the proxy record cannot see a 164-year increase. The problem of comparing daily modern instrumental temperature records to proxies is discussed by Renee Hannon here.

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climate-debate

Brown Bears Lived In The 73°N Siberian Arctic 3500 Years Ago…Today Their Northern Boundary Is 65°N

by K. Richard, Oct 14, 2024 in NoTricksZone

A new study provides still more evidence the Arctic was warmer than it is today as recently as a few thousand years ago.

In 2020 the well-preserved carcass of a Yakutian brown bear (Ursus arctos) was discovered buried in permafrost on the terrain of the treeless tundra Bolshoy Lyakhovsky Island in the Arctic Ocean, 73°N.

The Yakutian brown bear currently occupies only the forested regions of Eurasia, with a northern limit of northern Yakutia (Republic of Sakha), 65°N.

The female bear’s age has been dated to approximately 3500 years ago, during the Middle to Late Holocene. At that time the Arctic was warm enough at that latitude to support vegetation (grasses, shrubs) that only persist in the northern Yakutia region today.

The authors suggest brown bears may have been permanent residents of the Siberian Arctic’s islands from about 5000 years ago until a few thousand years ago, when, as today, the Arctic became too cold for the vegetation production requisite for their sustenance.

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climate-debate

Net Isotopic Signature of Atmospheric CO2 Sources and Sinks: No Change since the Little Ice Age

by D. Koutsoyiannis, March 14, 2024 in MDPI – (Open Access)

Abstract

Recent studies have provided evidence, based on analyses of instrumental measurements of the last seven decades, for a unidirectional, potentially causal link between temperature as the cause and carbon dioxide concentration ([CO2]) as the effect. In the most recent study, this finding was supported by analysing the carbon cycle and showing that the natural [CO2] changes due to temperature rise are far larger (by a factor > 3) than human emissions, while the latter are no larger than 4% of the total. Here, we provide additional support for these findings by examining the signatures of the stable carbon isotopes, 12 and 13. Examining isotopic data in four important observation sites, we show that the standard metric δ13C is consistent with an input isotopic signature that is stable over the entire period of observations (>40 years), i.e., not affected by increases in human CO2 emissions. In addition, proxy data covering the period after 1500 AD also show stable behaviour. These findings confirm the major role of the biosphere in the carbon cycle and a non-discernible signature of humans.
climate-debate

Antarctica Is Colder, Icier Now Than Any Time In 5000 Years. The Last Warm Period Was 1000 Years Ago.

by K. Richard, Apr 15, 2024 in NoTricksZone

More evidence emerges that Antarctica has undergone rapid glacier and sea ice expansion in recent centuries, in line with the long-term and recent Antarctic cooling trend.

West Antarctica’s mean annual surface temperatures cooled by more than -1.8°C (-0.93°C per decade) from 1999-2018 (Zhang et al., 2023).

Not just West Antarctica, but most of the continent also has cooled by more than 1°C in the 21st century. See, for example, the ~1°C per decade cooling trend for East Antarctica (2000 to 2018) shown in Fig. ES

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According to a new study, about 6000 years ago Antarctica’s Collins Glacier’s frontline was a full 1 km southwest of its current extent. The frontline advanced to today’s extent ~5000 years ago.

“Previous studies proposed that 6000 yr BP, the frontline position of the Collins Glacier was located 1 km further south west than the present, and that the current frontline was first attained at approximately 5000 yr BP.”

The glacier then continuously retreated south of the modern extent for another 4000 years, with peak ice loss 1000 years ago (as shown in the 1000-year “Proglacial lake environment” image). In the last 1000 years this glacier has rapidly re-advanced back to the glaciated extent from 5000 years ago, which is in line with the sustained cooling trend ongoing since the Medieval Warm Period.

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climate-debate

More New Studies Indicate There Has Been No Climate-Induced Precipitation Trend Since The 1800s

by K. Richard, Mar 11, 2024 in NoTricksZone

CO2-induced global warming was supposed to intensify the hydrological cycle and extreme precipitation. It hasn’t.

New research (Mitchell and Knapp, 2024) at a southeastern United States study site indicates there has been no significant trend in either total precipitation or intense rainfall events (IRE) over the last 250 years (1770-2020).

However, there was more IRE precipitation from 1936-1959 than from 1960-2020. In fact, the most recent 60 years has the lowest record of extreme precipitation during the study, with averages of 81.20 mm for 1770–1935, 230.45 mm for 1936–1959, but just 168.27 mm during 1960–2020.

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unclassified

A New 1787-2005 Temperature Reconstruction Determines The Coldest 50-Year Period Was 1940-1993

by K. Richard, Mar 4, 2024 in NoTricksZone

The warmest 50-year period in northeastern China occurred from 1844-1893.

Li et al., 2024

“Compared with single years, in general, high or low temperatures that persist for many years will more significantly affect the growth of trees [30]. When we defined years with T12-1 ≥ −10.73 °C (Mean + 1σ) and T12-1 ≤ −12.61 °C (Mean − 1σ) as extreme warm years and cold years, respectively, the reconstruction for the period of 1787–2005 contained 31 cold years and 36 warm years (Table 4). The extreme cold/warm events lasting for three or more consecutive years were discovered in 1965–1967 and 1976–1978/1791–1798, 1844–1849 and 1889–1891. An 11-year smoothing average of the reconstructed T12-1 series was performed to reveal multi-year and interdecadal variations and to detect the several prolonged cold and warm periods (Figure 5d). After smoothing with an 11-yr moving average, cold periods occurred in 1822–1830 (mean T12-1 = −12.7 °C) and 1957–1970 (mean T12-1 = −12.7 °C), while a warm period occurred in 1787–1793 (mean T12-1 = −10.4 °C) (Figure 5d). Rapid and sustained cooling was observed in the reconstructed series in the years 1790–1826 (T12-1 range −10.3 °C to −12.8 °C, mean = −12.0 °C) and 1939–1969 (T12-1 range −11.6 °C to −12.7 °C, mean = −12.1 °C), where the rates of cooling were about 0.067 °C/year and 0.035 °C/year, respectively (Figure 5d). The two cooling events may be due to the decrease in solar activity [48,49,50]. Using a 50-year time scale, the highest temperature occurring during 1787–2005 was from 1844 to 1893 (T12-1 range −12.79 °C to −9.41 °C, mean = −11.15 °C), similar results were also obtained by Zhu et al. and Jiang et al., while the lowest temperature was from 1940–1993 (T12-1 range −13.57 °C to −10.26 °C, mean = −12.13 °C) (Figure 5d) [33].”

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climate and geology

Geologically Generated Ice Cycles And Climate-Related Phenomena

by J.E. Kamis, Feb 28, 2024 in ClimateChangeDispatch

The term “Ice Age” implies that covering Earth’s surface with ice and then melting it is a single event.

As explained below, this process is not a single event but rather a reoccurring cycle that has three distinct phases: Ice Melt/End Phase, Ice Increase/Recovery Phase, and Normal Ice Extent/Stable Phase.

Ice Melt/End Phase

Approximately every 100,000 years, the Earth’s glaciers and seas reach their maximum extent. Suddenly and within 5,000 years nearly all the ice melts. I term this the Ice Melt Phase.

So, what causes this rapid melting of the ice? It is a geologically induced pulse of heat and gas emitted from all of Earth’s geological features. A more detailed explanation of the Ice Melt Phase follows.

In 1941 Serbian mathematician Milutin Milankovitch discovered that every 100,000 years, the Earth’s orbit around the sun, tilt angle of its axis, and wobble-type movement around the axis changes. Scientists called this process a Milankovitch Cycle.

Milankovitch concluded that these astronomical changes affected Earth’s long-term climate. Others have shown that these astronomical changes also act to greatly increase the gravitational stress on Earth.

Figure 1. 50,000-mile-long interconnected network of ocean floor fault zones and ice extent during an Ice Cycle. (Image credit Wikipedia, some labeling by J. Kamis).

In my opinion, this stress activates all of Earth’s geological features, most importantly the 50,000-mile-long interconnected network of deep ocean-floor fault zones (Figure 1). These fault zones form the boundary between continents and large segments of ocean-floor rock layers.

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

New Study Finds No Evidence Of A CO2-Driven Warming Signal In 60 Years Of IR Flux Data

by K. Richard, Jan 11, 2024 in NoTricksZone

“The real atmosphere does not follow the GHG [greenhouse gas] GE [greenhouse effect] hypothesis of the IPCC.” – Miskolczi, 2023

CO2 increased from 310 ppm to 385 ppm (24%) during the 60 years from 1948 to 2008. Observations indicate this led to a negative radiative imbalance of -0.75 W/m². In other words, increasing CO2 delivered a net cooling effect – the opposite of what the IPCC has claimed should happen (Miskolczi, 2023).

Also, there is “no correlation with time and the strong signal of increasing atmospheric CO2 content in any time series,” which affirms “the atmospheric CO2 increase cannot be the reason for global warming.”

“The Arrhenius type greenhouse effect of the CO2 and other non-condensing GHGs is an incorrect hypothesis and the CO2 greenhouse effect based global warming hypothesis is also an artifact without any theoretical or empirical footing.”

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climate-debate

UK Rainfall In 2023

by P. Homewood, Jan 7 ,2024 in NotaLotofPeopleKonwThat

image

https://www.metoffice.gov.uk/hadobs/hadukp/data/monthly/HadEWP_monthly_totals.txt

Last year was a wet one in England & Wales, the 7th wettest on record. (The UK series has a similar result).

We routinely hear claims that the climate is wetter because a warmer atmosphere can hold more moisture, (while also being told we will get more droughts!). However the fact that we have had similarly wet years in the distant past, such as 1768, 1852, 1872, 1877, 1882, 1903 and 1960, rather demolishes that argument.

The major factor behind last year’s high rainfall was that the number of rain days was also one of the highest on record since 1931, when Met Office daily data begins. In short, annual rainfall was high because of weather, not climate.

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climate-debate

In Climatology, Whatever Happened To Evidence-Based Science?

by J. Hellner, Nov 21, 2023 in ClimateChangeDispatch

Isn’t it time that journalists and students are taught to do research and ask questions about the climate instead of just regurgitating talking points pushing the green agenda?

We are constantly told that storms, floods, droughts, and other natural disasters are growing in frequency and intensity—so why don’t we see specific examples? [emphasis, links added]

Like the severe drought and warm period in Europe in 1540 when temperatures were 9–13 degrees above today’s averageduring the Little Ice Age?

For eleven months, there was practically no rain, and temperatures were five to seven degrees [Celsius] [9–13°F] above the normal values of the 20th century; in many places, summer temperatures must have exceeded 40°C (104°F).

Many forests in Europe went up in flames, choking smoke darkened the sun, and not a single thunderstormwas reported in the summer of 1540.

Water was already scarce in May, wells and springs dried up, mills stood still, people starved, and livestock was slaughtered. Estimates are that in 1540, half a million people died, mostly from dysentery.

Or what about the massive fires in the United States in 1871? In 1871, the Midwestern United States had a severe drought and warm weather, clearly not caused by humans and our use of natural resources.

As a result of this heat and drought, there were severe fires throughout the Midwest, including the Great Chicago Fire.

The temperature was 85 degrees on October 8, 1871. This year the high was 55 degrees, or thirty degrees cooler.

Why isn’t Chicago warmer, after 152 years, with all the cement, people, and gas vehicles and equipment if they all cause warming?

The Chicago fire alone caused $200 million in damages, which is the equivalent of over $5 billion today.

I am 70 years old, and I don’t recall serious fires during my lifetime in the Midwest.

The narrative that humans and our use of natural resources are to blame for warming temperatures, in turn creating an existential threat to our survival, is contrary to the data and facts; scientific honesty would be forming a narrative based on the evidence, instead of forcing “evidence” to fit a story.

What about the Medieval Warm Period 1,000 years ago where temperatures were similar to today? What caused that warming since it clearly wasn’t man’s use of natural resources?

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climate-debate

North Atlantic’s marine productivity may not be declining, according to new study of older ice cores

by Universiy of Washington, Nov 13, 2023 in PhysOrg

To paraphrase Mark Twain, reports of declining phytoplankton in the North Atlantic may have been greatly exaggerated. A prominent 2019 study used ice cores in Antarctica to suggest that marine productivity in the North Atlantic had declined by 10% during the industrial era, with worrying implications that the trend might continue.

But new research led by the University of Washington shows that —on which larger organisms throughout the marine ecosystem depend—may be more stable than believed in the North Atlantic. The team’s analysis of an going back 800 years shows that a more complex atmospheric process may explain the recent trends.

The study was published in the Proceedings of the National Academy of Sciences.

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climate-debate

New Study: Antarctic Sea Ice Completed Half Its Deglacial Retreat 1000s Of Years Before CO2 Began Rising

by K. Richard, Nov 16, 2023 in NotricksZone

The timing of the dramatic Antarctic sea ice decline during the last deglaciation suggests solar forcing and sea ice retreat “instigated” century-scale climate warming and atmospheric CO2 change. This would appear to challenge the perception CO2 plays a causal role in glacial-interglacial sea ice and climate changes.

From ~21,000 to 19,500 years ago, when CO2 was thought to have been at its lowest point in the Quaternary ice age (~180 ppm), the sea ice surrounding East and West Antarctica completed 50% of its eventual deglaciation-era decline (Sadatzki et al., 2023).

“[I]ndependent lines of evidence supporting that early sea ice and surface ocean changes in the Southern Ocean initiated as early as ~19.5 ka ago (with signs of summer sea ice retreat in our reconstruction as early as ~21 ka ago) and thus (at least) about 2 ka before major deglacial changes in global ocean circulation, climate, and atmospheric CO2.”

The increase in 65°S insolation during these millennia was deemed sufficient to drive this magnitude of sea ice retreat.

“This early increase in local integrated summer insolation at 65°S, which is independent of the longitude, may have thus provided enough energy to initiate melting of the near-perennial sea ice cover in late glacial.”

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climate-debate

Massive iceberg discharges during the last ice age had no impact on nearby Greenland, raising new questions about climate dynamics

by WUWT, Apr 24, 2023

CORVALLIS, Ore. – During the last ice age, massive icebergs periodically broke off from an ice sheet covering a large swath of North America and discharged rapidly melting ice into the North Atlantic Ocean around Greenland, triggering abrupt climate change impacts across the globe.

These sudden episodes, called Heinrich Events, occurred between 16,000 and 60,000 years ago. They altered the circulation of the world’s oceans, spurring cooling in the North Atlantic and impacting monsoon rainfall around the world.

But little was known about the events’ effect on nearby Greenland, which is thought to be very sensitive to events in the North Atlantic. A new study from Oregon State University researchers, just published in the journal Nature, provides a definitive answer.

“It turns out, nothing happened in Greenland. The temperature just stayed the same,” said the study’s lead author, Kaden Martin, a fourth-year doctoral candidate in OSU’s College of Earth, Ocean, and Atmospheric Sciences. “They had front-row seats to this action but didn’t see the show.”

Instead, the researchers found that these Heinrich events caused rapid warming in Antarctica, at the other end of the globe.

The researchers anticipated Greenland, in close proximity to the ice sheet, would have experienced some kind of cooling. To find that these Heinrich Events had no discernible impact on temperatures in Greenland is surprising and could have repercussions for scientists’ understanding of past climate dynamics, said study co-author Christo Buizert, an assistant professor in the College of Earth, Ocean, and Atmospheric Sciences.

“If anything, our findings raise more questions than answers,” said Buizert, a climate change specialist who uses ice cores from Greenland and Antarctica to reconstruct and understand the Earth’s climate history. “This really changes how we look at these massive events in the North Atlantic. It’s puzzling that far-flung Antarctica responds more strongly than nearby Greenland.”

Scientists drill and preserve ice cores to study past climate history through analysis of the dust and tiny air bubbles that have been trapped in the ice over time. Ice cores from Greenland and Antarctica provide important records of Earth’s atmospheric changes over hundreds of thousands of years.

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better to know...?, climate-debate

Earth’s Mean Annual Temp Was Warmer 31,000 Years Ago… North Pole 22°C Warmer

by K. Richard, Apr 18, 2023 in ClimateChangeDispatch

Earth’s average annual temperature fluctuated by as much as 35°C (at high latitudes) from one millennial-scale period to the next during the last glacial period.

A recently-published 2-part study (Smul′skii, 2022a and 2022b) utilizes established orbital and insolation data to calculate Earth’s average temperature today (0 k years ago), 14.4°C, and at 25°N, 45°N, 65°N, 80°N, 0°, -25°S, -45°S, -65°S, and -80°S during 3 paleo epochs: 15.9 k years ago, 31.3 k years ago, and 46.4 k years ago. [emphasis, links added]

The Global Annual Temperature Of Earth: 14.4°C – The Same As A Century Ago

Consistent with dozens of other calculations, Smul′skii (2022a) determined the mean annual temperature of the modern period, which includes 1991-2018, ranges between 14.07 and 14.41°C.

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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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