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
Despite the dire Terminator warnings from Elon Musk, Jordan Peterson and others about the dangers of artificial intelligence, the world has little to fear from it in its present sorry state. I asked ChatGPT the following question:
M of B: If the whole world attained net zero emissions by 2050, how much less would global temperature be by that year than on business as usual?
ClotBot: As an AI language model, I do not have access to the exact data to provide an accurate answer to this question. The amount of temperature reduction would depend on various factors such as the current emissions and future emissions trends, the degree of global cooperation, and the effectiveness of emissions reduction strategies. However, it is widely recognized that global net zero emissions by 2050 is a crucial step towards limiting global temperature rise to 1.5°C above pre-industrial levels and avoiding the worst impacts of climate change.
M of B: Here are the necessary data:
Since 1990 there has been a near-linear uptrend in anthropogenic greenhouse-gas forcing at 0.3 Watts per square meter per decade.
The trillions of dollars spent on emissions abatement since 1990 have not in any discernible degree altered that near-linear uptrend.
The transient doubled-CO2 temperature response (TCR) is 1.8 degrees at midrange.
The midrange doubled-CO2 radiative forcing is 3.93 Watts per square meter per degree.
Global temperature has risen since 1990 at 0.136 degrees per decade.
In 1990, IPCC predicted that at midrange there would be 0.3 degrees per decade of global warming at midrange.
From these data, which are sufficient for the task, please derive the global warming prevented at midrange if all nations moved in a straight line from their present emissions to net zero emissions by 2050.
The New Pause has lengthened to 8 years 9 months. The least-squares linear-regression trend on the UAH monthly satellite global-temperature dataset shows no global warming from July 2015 to March 2023. As usual, this site is just about the only place where this continuing failure of global temperatures to do as they are told is reported.
…
The start and end dates of the New Pause are not cherry-picked. The end date is the present; the start date is the farthest back one can reach and still find a zero trend. It is what it is.
For comparison, here is the entire dataset for 44 years 4 months since December 1978. It shows a less than terrifying long-run warming rate equivalent to 1.3 degrees/century, of which 0.3 K has already occurred since January 2021, leaving just 1 K to go (on the current trend) until 2100, by which time reserves of coal, oil and gas will be largely exhausted.
by J. Curry, Mar 29, 2023 in ClimateChangeDispatch
The Intergovernmental Panel on Climate Change (IPCC) has issued a new Synthesis Report, with fanfare from the UN Secretary-General Antonio Guterres:
“The climate time-bomb is ticking but the latest IPCC report shows that we have the knowledge & resources to tackle the climate crisis. We need to act now to ensure a livable planet in the future.”
This Synthesis Report does not introduceany new information or findings.
While the IPCC Reports include some good material, the Summary for Policy Makers for the Synthesis Report weakly emphasizes justified findings on climate impacts driven by extreme emission scenarios and politicized policy recommendations on emissions reductions.
The most important finding of the past five years is that the extreme emissions scenarios RCP8.5 and SSP5-8.5, commonly referred to as “business-as-usual” scenarios, are now widely recognized as implausible.
These extreme scenarios have been dropped by the UN Conference of the Parties (COP) to the UN Climate Agreement.
However, the new Synthesis Report continues to emphasize these extreme scenarios, while this important finding is buried in a footnote:
“Very high emission scenarios have become less likely but cannot be ruled out.”
The most recent Conference of the Parties (COP27) is working from a baseline temperature projectionbased on a medium emissions scenario of 2.5°C by 2100.
It is all over the news, another climate change report from the IPCC – the United Nation’s Intergovernmental Panel on Climate Change. Of course, it tells us that the end is nigh unless we do something to prevent temperatures exceeding 1.5 degrees Celsius. Meanwhile, not one of the contributors has any proven capacity to accurately forecast the weather more than a few days in advance, nor much of an idea of the quality of the temperature data inputted into the simulation models claiming the Earth is burning up. Yet they claim to be able to forecast temperatures years in advance and repeat over and over the value of 1.5 C as representing a tipping point.
The reality is that annual maximum temperatures across Australia were mostly falling, and by much more than 1.5 C, from at least 1910 to 1960 and then increasing, and by more than 1.5 C, since 1960.
There are few locations across Australia where temperatures have been recorded at the one place and using standard equipment (including in a Stevenson screen with a mercury thermometer) much before 1908. Darwin in the Northern Territory and Richmond in Queensland are special because they have long and relatively reliable temperature records. Making a single adjustment to the Darwin temperature record to correct for the move from the post office to the airport (after the post office was bombed in WW II), it is evident from the chart that both temperature series show cooling and then warming over the last century and by much more than 1.5 C over periods of less than a decade.
Each of mainstream media outlets predict that “climate doom” is just around the corner, and they’re all wrong.
The reason? The newest IPCC report laments the fact that Earth will soon pass the 1.5°C level of temperature rise, seen in the projection in Figure 1. The current extrapolation is to reach 1.5°C by April 2035.
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Based on that projection, the IPCC and the media predict very bad things will happen if we don’t “act now before it’s too late.” The most recent report in the AR6 series contains no new information, rather it reiterates the warnings made the physical science portion of the report issued in the summer of 2021, which also mentioned approaching 1.5°C.
Interestingly, the “before it’s too late” language has been used since 2005, when worry about just 1°C was the big doomsday news:
NASA scientist Jim Hansen introduced the “too late” language about climate change in 2005, arguing that “We have to stabilize emissions of carbon dioxide within a decade, or temperatures will warm by more than one degree [C]… we don’t have much time left”.
We heard the same type of language in 2007, when the IPCC released their Fourth Assessment Report. The headlines in The Guardian said “time is running out” and warming “could be irreversible.”
One of the most frightening aspects of global warming, aka “climate change” is the graphs produced from temperature data for public consumption and trumpeted by an unquestioning and compliant media. When it comes to measuring climate, in order to actually see any temperature differences over the last century, they must be highly magnified using the temperature anomaly method.
The Version 6 global average lower tropospheric temperature (LT) anomaly for February 2023 was +0.08 deg. C departure from the 1991-2020 mean. This is up from the January 2023 anomaly of -0.04 deg. C.
The linear warming trend since January, 1979 remains at +0.13 C/decade (+0.11 C/decade over the global-averaged oceans, and +0.18 C/decade over global-averaged land).
Fourteen years ago, a new climate myth was born. A grand solar minimum (GSM) was in the making that would not only reverse global warming but plunge the planet into a new Little Ice Age, surprising the warming alarmists and causing undue suffering. The time has come to bury that myth.
1. The origin of the myth
The deep solar minimum of 2008-2009 was a complete surprise to solar physicists. They did not know that solar activity could become so low because it had not occurred during the time of solar observations with modern instrumentation. In 2009, a solar scientist named Habibullo Abdussamatov published a paper in Russian in which he argued that the following years would see a major cooling based on the onset of a new GSM. His evidence was
The low solar activity of the then ongoing solar cycle (SC) minimum 23-24.
A bicentennial cycle in solar activity that supposedly decreased solar activity after 1600 and after 1800
The pause in global warming since 1998
Figure 1. From Abdussamatov 2009. “The Sun defines the climate”. Nauka i Zhizn, N1, pp. 34-42.
This prediction reached the West and became very popular, like any catastrophic prediction, actually. Articles about the arrival of a GSM proliferated on climate blogs, such as the one on WUWT: The ‘Baby Grand’ has arrived.
Other scientists, such as Livingston & Penn and de Jager & Duhau, joined Abdussamatov in 2009 in proposing the arrival of a GSM, though being more cautious about its climatic effects. It went so far as to threaten the global warming narrative at a time under assault from the Pause and Climategate. Thus, none other than Stefan Rahmstorf came to their defense saying that according to the models
“a new Maunder-type solar activity minimum cannot compensate for global warming caused by human greenhouse gas emissions.”
by N. Scafetta, Feb 3, 2023 in MDPI, Earth Science
Global climate models (GCMs) from the sixth Coupled Model Intercomparison Project Phases (CMIP6) have been employed to simulate the twenty-first-century temperatures for the risk assessment of future climate change. However, their transient climate response (TCR) ranges from 1.2 to 2.8 °C, whereas their equilibrium climate sensitivity (ECS) ranges from 1.8 to 5.7 °C, leading to large variations in the climatic impact of an anthropogenic increase in atmospheric CO2 levels. Moreover, there is growing evidence that many GCMs are running “too hot” and are hence unreliable for directing policies for future climate changes. Here, I rank 41 CMIP6 GCMs according to how successfully they hindcast the global surface warming between 1980 and 2021 using both their published equilibrium climate sensitivity (ECS) and transient climate response (TCR) estimates. The sub-ensemble of GCMs with the best performance appears to be composed of the models with ECS ranging between 1.8 and 3.0 °C (which confirms previous studies) and TCR ranging between 1.2 and 1.8 °C. This GCM sub-ensemble is made up of a total of 17 models. Depending on the emission scenarios, these GCMs predict a 2045–2055 warming of 1.5–2.5 °C compared to the pre-industrial era (1850–1900). As a result, the global aggregated impact and risk estimates seem to be moderate, which implies that any negative effects of future climate change may be adequately addressed by adaptation programs. However, there are also doubts regarding the actual magnitude of global warming, which might be exaggerated because of urban heat contamination and other local non-climatic biases. A final section is dedicated to highlighting the divergences observed between the global surface temperature records and a number of alternative temperature reconstructions from lower troposphere satellite measurements, three-ring-width chronologies, and surface temperature records based on rural stations alone. If the global warming reported by the climate records is overestimated, the real ECS and TCR may be significantly lower than what is produced by the CMIP6 GCMs, as some independent studies have already suggested, which would invalidate all of the CMIP6 GCMs.
Claims the Swedish Scandes are unprecedentedly warm and tree-covered today “appear as large and unfounded exaggerations,” as the “climate and arboreal responses” of the last few decades “are still inside the frames of natural historical variation.” – Kullman, 2022 and Kullman, 2022a
Extensive birch forest fossils can be dated to the early- to mid-Holocene in northern Scandinavian regions, indicating these warmth-sensitive trees could exist in climates that are too cold for them to grow in today. This documents a much warmer period, “at least 3°C higher than during the past few decades,” 3000 to 10,000 years ago, or when CO2 was about 265 ppm (Kullman, 2022).
Contrary to modeler opinions, “there is little factual nourishment” to support modern projections that the Swedish Scandes will soon be returning to the subalpine birch forest climates of past millennia. The observed forest advancement in recent decades “is so small” that these modeling claims appear to be “unfounded exaggerations.”
“In the southernmost Swedish Scandes, pine has already “leap-frogged” over receding the birch forest-limit (Kullman 2014, 2019). That scenario would mimic the arboreal landscape during the early Holocene and shift to a landscape unseen for thousands of years (cf. Blűthgen 1942; MacDonald et al. 2008, Macias-Fauria et al. 2012). During that epoch, summer temperatures are inferred to have been at least 3°C higher than during the past few decades.”
“At the landscape level, the obtained changes contribute to a greater and lusher landscape, in contrast to the dire conditions during the Little Ice Age, more than 100 years ago (Kullman 2010, 2015). Currently, there is little factual nourishment to flourishing projections stating that a major part of Swedish alpine areas is on verge of transformation to subalpine birch forest (e.g. Moen et al. 2004). Apparently, climate and arboreal responses are still inside the frames of natural historical variation, as inferred by several authors (e,g. Hammarlund et al. 2004; Bergman et al. 2005; Kullman 2013, 2017a, b; Kullman & Öberg 2018, 2020).”
“Given that the current relatively warm climate phase continues, the subalpine birch forest belt may eventually recede and give way to a subalpine pine belt. The obtained modest forest-limit advancement is so small that flourishing model simulations of extensive birch forest expansion over most of the current alpine tundra appear as large and unfounded exaggerations.”
Tree remnants (trunks, cones, roots, etc.) found at northern Sweden mountain sites 500 to 700 meters atop where the 21st century tree line ends imply the early-Holocene (~13,000 to 7000 years ago) climate was significantly warmer than today in this region (Kullman, 2022a).
The temperature lapse rate for the Swedish Lapland region is 0.6°C/100 m. Accounting for glacio-isostatic uplift, this tree line elevation implies surface air temperatures were 3.6°C higher than today during the Early Holocene.
The Version 6 global average lower tropospheric temperature (LT) anomaly for January 2023 was -0.04 deg. C departure from the 1991-2020 mean. This is down from the December 2022 anomaly of +0.05 deg. C.
The linear warming trend since January, 1979 now stands at +0.13 C/decade (+0.11 C/decade over the global-averaged oceans, and +0.18 C/decade over global-averaged land).
Various regional LT departures from the 30-year (1991-2020) average for the last 13 months are:
YEAR
MO
GLOBE
NHEM.
SHEM.
TROPIC
USA48
ARCTIC
AUST
2022
Jan
+0.03
+0.06
-0.00
-0.23
-0.13
+0.68
+0.10
2022
Feb
-0.00
+0.01
-0.01
-0.24
-0.04
-0.30
-0.50
2022
Mar
+0.15
+0.27
+0.03
-0.07
+0.22
+0.74
+0.02
2022
Apr
+0.26
+0.35
+0.18
-0.04
-0.26
+0.45
+0.61
2022
May
+0.17
+0.25
+0.10
+0.01
+0.59
+0.23
+0.20
2022
Jun
+0.06
+0.08
+0.05
-0.36
+0.46
+0.33
+0.11
2022
Jul
+0.36
+0.37
+0.35
+0.13
+0.84
+0.55
+0.65
2022
Aug
+0.28
+0.31
+0.24
-0.03
+0.60
+0.50
-0.00
2022
Sep
+0.24
+0.43
+0.06
+0.03
+0.88
+0.69
-0.28
2022
Oct
+0.32
+0.43
+0.21
+0.04
+0.16
+0.93
+0.04
2022
Nov
+0.17
+0.21
+0.13
-0.16
-0.51
+0.51
-0.56
2022
Dec
+0.05
+0.13
-0.03
-0.35
-0.21
+0.80
-0.38
2023
Jan
-0.04
+0.05
-0.14
-0.38
+0.12
-0.12
-0.50
The full UAH Global Temperature Report, along with the LT global gridpoint anomaly image for January, 2023 should be available within the next several days here.
The global and regional monthly anomalies for the various atmospheric layers we monitor should be available in the next few days at the following locations:
Independent analyses from multiple independent sources indicate Arctic Siberia was 3 to 5°C warmer than today during the peak of the last glacial, or when CO2 levels were below 200 ppm.
Measurements from Antarctica’s ice sheet are almost invariably used to characterize both the global-scale atmospheric CO2 levels and climate for the last 10s to 100s of thousands of years.
But it is rather odd that Antarctica’s climate is considered globally representative (i.e., “global warming”) since there has been no warming here for the last seven decades.
Further, ice samples from Antarctica have CO2 values that range between 900 and 2900 ppm (Matsuo and Miyake, 1966) for the modern period (i.e., the 1960s). These values are far outside the range of the accepted modern global atmospheric values (~300 to 400 ppm).
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.”
As in years past, the annual rollout of the GISTEMP, NOAA, HadCRUT and Berkeley Earth analyses of the surface temperature record have brought forth many stories about the long term trends and specific events of 2022 – mostly focused on the impacts of the (ongoing) La Niña event and the litany of weather extremes (UK and elsewhere having record years, intense rainfall and flooding, Hurricane Ian, etc. etc.).
But there are a few things that don’t get covered much in the mainstream stories, and so we can dig into them a bit here.
What influence does ENSO really have?
It’s well known (among readers here, I assume), that ENSO influences the interannual variability of the climate system and the annual mean temperatures. El Niño events enhance global warming (as in 1998, 2010, 2016 etc.) and La Niña events (2011, 2018, 2021, 2022 etc.) impart a slight cooling.
GISTEMP anomalies (w.r.t. late 19th C) coded for ENSO state in the early spring.
Consequently, a line drawn from an El Niño year to a subsequent La Niña year will almost always show a cooling – a fact well known to the climate disinformers (though they are not so quick to show the uncertainties in such cherry picks!). For instance, the trends from 2016 to 2022 are -0.12±0.37ºC/dec but with such large uncertainties, the calculation is meaningless. Far more predictive are the long term trends which are consistently (now) above 0.2ºC/dec (and with much smaller uncertainties ±0.02ºC/dec for the last 40 years).
It’s worth exploring quantitatively what the impact is, and this is something I’ve been looking at for a while. It’s easy enough correlate the detrended annual anomalies with the ENSO index (maximum correlation is for the early spring values), and then use that regression to estimate the specific impact for any year, and to estimate an ENSO-corrected time series.
The HadCRUT3 global temperature trend was recorded as 0.03°C per decade during the global warming hiatusyears of 2000-2014 (Scafetta, 2022).
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This was increased to 0.08°C per decade by version 4, as the overseers of the HadCRUT data conveniently added 0.1°C to 0.2°C to the more recent anomalies.
Today, in HadCRUT5, the 2000-2014 temperature trend has been adjusted up to 0.14°C per decade when using the computer model-infilling method.
So, within the last decade, a 15-year temperature trend has been changed from static to strong warming.
Each year, we invite Net Zero Watch readers to enter our annual Global Temperature Prediction Competition, in which we try to outdo the Met Office for the accuracy of our soothsaying.
For 2022, the Met Office predicted an average of between 0.97 and 1.21°C (midpoint 1.09°C) above pre-industrial temperatures for the HadCRUT5 index. However, Net Zero Watch readers, as is their wont, went slightly lower, with the median prediction coming in at 1.00°C, and the mode at 1.03°C. This is all shown in the graph below, alongside the correct value, just announced by the Met Office, of 1.16°C.
As you can see, none of our competition entrants got the right answer. There were three people just above, and three more just below. We’ll put all six names into a hat to pick a winner. We’ll be in contact shortly.
If you’d like to enter the 2023 competition, now is your chance!
As always, the prize is a bottle of hooch of your choice, and a book from the GWPF or Net Zero Watch publication lists.
The Met Office reckons on a relatively sharp warming, suggesting HadCRUT5 will come in at between 1.08 and 1.32°C above pre-industrial (with a central estimate of 1.20°C). That’s 0.04°C above last year’s outturn, which doesn’t seem unreasonable, assuming we come out of the La Nina conditions that prevailed in 2022.
To enter, click here (opens a new site). Good luck!
The unusually mild weather at the turn of the year in Central Europe has strengthened the belief of many in Germany that CO2-induced global warming is in full swing. Globally – and this is the only thing that matters – temperatures are developing in a different direction.
If we take the average of the last years, the global temperature has been constant for 8 years and 4 months.
In December, the deviation of the global temperature from the 30-year average of the satellite-based measurements of the University of Alabama (UAH) dropped again, to 0.05 degrees Celsius. To be sure, there is a long-term temperature increase through 2015. But it has averaged only 0.13 degrees Celsius per decade since 1979.
Weakening North Atlantic Oscillation
But it gets even better: the latest scientific studies show for Europe that it will first go slightly downhill for 15-20 years.
Some climate science heavyweights recently caused a stir in the Nature journal “Climate and Atmospheric Science.” Katja Matthes, director of the GEOMAR Helmholtz Centre for Ocean Research in Kiel, Johann Jungclaus of the Max Planck Institute for Meteorology in Hamburg and Nour-Eddine Omrani of the Norwegian Bjerknes Centre for climate research published a study showing that we are facing a weakening of the North Atlantic Oscillation, a cooling of the North Atlantic and a related global temperature development as between 1950 and 1970 (the authors say in their summary).
The graph shows the decline in North Atlantic temperatures by 2040, but because of the global warming trend, temperatures are not falling back to 1950-1970 levels, explains one of the authors, Eddine Omrani. The expected pause in warming gives us time, Omrani says, to work out technical, political and economic solutions before the next warming phase, which will take over again from about 2050.
Why is the coming cooling in Europe not being reported ?
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.
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).
We all know that Santa’s workshop is somewhere in the Arctic, producing toys for the world’s children. Also north of the Arctic Circle is Professor Humlum’s office at the Unversity of Svalbaard wherein he toils each month to update a report on climate. The first chart in that report is the UAH temperature for the lower troposphere, copied following and annotated with lines showing the evident trends:
Figure 1: UAH global temperature anomaly
In the period from 1978 to 2015, the lower bound of the record is shown by the orange line. Then there was a period of a couple of years in which the temperature anomaly was in a narrow, steep uptrend channel. The temperature anomaly broke up from that channel due to the 2016 El Nino.
Since that 2016 El Nino, two parallel upper bounding lines have formed, in downtrend. The lower green one is formed by six points. The upper red line is formed from only two points – the minimum to make a line – but is notable in that it is parallel to the green line. So climate isn’t a randowm walk. There is some physical process that limits how far temperature excursions go.
The uptrend from the beginning of the satellite record in 1978 to 2015 was 0.4°C over 36 years. That equates to 0.000926°C per month. If we take that amount from each monthly temperature anomaly, cumulatively, we produce the following graph of the detrended monthly temperature anomaly distribution from 1978 to 2015:
The Earth’s climate has undergone some big changes, from global volcanism to planet-cooling ice ages and dramatic shifts in solar radiation. And yet life, for the last 3.7 billion years, has kept on beating.
Now, a study by MIT researchers in Science Advances confirms that the planet harbors a “stabilizing feedback” mechanism that acts over hundreds of thousands of years to pull the climate back from the brink, keeping global temperatures within a steady, habitable range.
Just how does it accomplish this? A likely mechanism is “silicate weathering” — a geological process by which the slow and steady weathering of silicate rocks involves chemical reactions that ultimately draw carbon dioxide out of the atmosphere and into ocean sediments, trapping the gas in rocks.
Scientists have long suspected that silicate weathering plays a major role in regulating the Earth’s carbon cycle. The mechanism of silicate weathering could provide a geologically constant force in keeping carbon dioxide — and global temperatures — in check. But there’s never been direct evidence for the continual operation of such a feedback, until now.
The new findings are based on a study of paleoclimate data that record changes in average global temperatures over the last 66 million years. The MIT team applied a mathematical analysis to see whether the data revealed any patterns characteristic of stabilizing phenomena that reined in global temperatures on a geologic timescale.
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Journal Reference:
Constantin W. Arnscheidt, Daniel H. Rothman. Presence or absence of stabilizing Earth system feedbacks on different time scales. Science Advances, 2022; 8 (46) DOI: 10.1126/sciadv.adc9241
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.”
A major survey into the accuracy of climate models has found that almost all the past temperature forecasts between 1980-2021 were excessive compared with accurate satellite measurements. The findings were recently published by Professor Nicola Scafetta, a physicist from the University of Naples. He attributes the inaccuracies to a limited understanding of Equilibrium Climate Sensitivity (ECS), the number of degrees centigrade the Earth’s temperature will rise with a doubling of carbon dioxide.
Scientists have spent decades trying to find an accurate ECS number, to no avail. Current estimates range from 0.5°C to around 6-7°C. Without knowing this vital figure, the so-called ‘settled’ science narrative around human-caused climate change remains a largely political invention, not a credible scientific proposition. Professor Scafetta has conducted extensive work into climate models and is a long-time critic of their results and forecasts. In a previous work, he said many of the climate models should be “dismissed and not used by policymakers”. Along with around 250 professors, he is a signatory to the World Climate Declaration which states there is no climate emergency and also notes climate models are “not remotely plausible as global tools”.
Scafetta’s latest work grouped 38 major climate models into low, medium and high ECS values, ranging between 1.8°C and 5.7°C. He found that models in the medium and high category “ran hot” in over 95% and 97% of cases respectively. The lower models were said to have done better when compared to global warming calculated for the period by the major surface datasets of 0.52-0.58°C. But the UAH satellite data showed warming up to 30% less during this period, suggesting even the low warming models produced “excessive warming” from 1980-2021.
According to Scafetta, these results are showed that the ECS figure could be as low as 1.2-2°C. Particular concern is expressed about surface temperature records that “appear to be severely affected by non-climatic warming biases”. Scafetta concludes that surface-based temperature records are likely to be affected by warming biases, such as the urban heat island effect due to expanding urban development, and subject to natural oscillations that are not reproduced by climate models. He concludes: “The global warming expected for the next few decades may be even more moderate than predicted by the low ECS-GCMs [Global Circulation Models], and could easily fall within a safe temperature range where climate adaptation policies will suffice.”
Figure 1: UAH global temperature anomaly