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josh-j

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Re: Global Surface Air Temperatures
« Reply #2250 on: August 26, 2020, 11:36:16 PM »
For what its worth (not much, I'm a mere lurker), it seems this is the right thread for Glenn's post.

I would just add that a string of warm months doesn't necessarily mean a causal link to Covid, especially since sinilar patterns are seen in other years.

But isn't this thread the place to discuss that? 🙂

<How does global aerosol dimming work? Where do we see it? The anomalies at the top of the world on both sides clearly indicate something else, namely ongoing atmospheric changes due to global warming. As a rule of the thumb when a moderator says this is not the proper thread including this hint: The aerosol masking effect is more local to the pollution sources so it´s not involved here kassy>
« Last Edit: August 27, 2020, 09:40:16 AM by kassy »

glennbuck

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Re: Global Surface Air Temperatures
« Reply #2251 on: August 27, 2020, 12:37:24 AM »
For what its worth (not much, I'm a mere lurker), it seems this is the right thread for Glenn's post.

I would just add that a string of warm months doesn't necessarily mean a causal link to Covid, especially since sinilar patterns are seen in other years.

But isn't this thread the place to discuss that? 🙂

Ok i will put these back here then.

This type of anomaly does not exist in the atmospheric record. Offering an indication that the reduction in aerosol masking effect this year is happening, to what degree it is changing temperatures is the question, with a 20% reduction in the aerosol masking effect reduction in 2020, compared to 100% in the below published scientific journal in 2018.

This would indicate a 0.05C-0.11C effect from a 20% reduction from the aerosol masking effect compared to a 100% reduction in the below study. Still a large jump as 0.05C-0.11C would normally happen over a 3 to 10 year period and this would of happened over a 6 months period.

The models simulate an additional global warming of around 0.7°C when fully removing Anthropogenic aerosols, with a model range of (0.5, 1.1)°C.

https://agupubs.onlinelibrary.wiley.com/doi/full/10.1002/2017GL076079

This does not include future reductions in the aerosol masking effects from reduction in consumption/industrial activity globally from the pandemic and second great depression in the next 2 years.

As we can see from the air temperature rank in the 4th chart in the global lockdown period, April, May, June, July shot up to 6,1,2,1 in warmest years. Jan, Feb, March were 20,13,32 and looking below average, China did not shut down most of its country in there Lockdown only the Wuhan    area at the end of Jan.
« Last Edit: August 27, 2020, 02:15:35 AM by glennbuck »

sark

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Re: Global Surface Air Temperatures
« Reply #2252 on: August 27, 2020, 01:11:45 AM »
Aerosol unmasking doesn't explain 2019
I am not a scientist

glennbuck

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Re: Global Surface Air Temperatures
« Reply #2253 on: August 27, 2020, 01:44:56 AM »
Aerosol unmasking doesn't explain 2019

Was posting comparison to 2019/2020, would be good if you posted your thoughts here about global dimming and 2020 weather sark, hope you dont mind me using your temperature charts anomaly.

oren

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Re: Global Surface Air Temperatures
« Reply #2254 on: August 27, 2020, 04:01:46 AM »
Has there been an actual reduction of aerosols, is there some measurement data supporting this? Where does the 20% come from?

sark

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Re: Global Surface Air Temperatures
« Reply #2255 on: August 27, 2020, 04:10:56 AM »
Aerosol unmasking doesn't explain 2019

Was posting comparison to 2019/2020, would be good if you posted your thoughts here about global dimming and 2020 weather sark, hope you dont mind me using your temperature charts anomaly.

not at all.  I'll point out that we really saw amplified transport to the pole in 2019 with a very large signal at 500mb height anomalies.  anticyclones began flooding to the pole after the sudden final warming of the winter polar vortex.  This split the tropospheric vortex very badly, and we saw continued breakup of the TPV in May - August of 2019.  This period marks the highest 500mb geopotential heights in the record over the North Pole.

Similarly, 2020 had a dynamic final warming of the NH strat PV...

Now the transport is seemingly coming in at a much lower level, as 925mb temperatures have suddenly ripped north of +4C over 4 months.  Unprecedented.
I am not a scientist

Archimid

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Re: Global Surface Air Temperatures
« Reply #2256 on: August 27, 2020, 11:20:34 AM »
Given humanity's current governance and existing trends, limiting warming to 3C isn't going to happen either, barring some social, political or engineering miracle.

We need "miracles" in all three. Miracles happen more often to those who try to make them happen. So in theory if "we" try hard enough we can increase the likelihood of miracles.
I am an energy reservoir seemingly intent on lowering entropy for self preservation.

glennbuck

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Re: Global Surface Air Temperatures
« Reply #2257 on: August 27, 2020, 04:28:56 PM »
Has there been an actual reduction of aerosols, is there some measurement data supporting this? Where does the 20% come from?

I would imagine there has been a large reduction of aerosols based on most of the world was in Lockdown for 3 months, that speaks for itself without any need for evidence that this would reduce aerosols by a large amount, the evidence of how much will be published in time. Below are some articles i found on this.

The 20% is just a rough estimate based on reduced industrial activity,GDP, flights grounded, reduction in car travel, holidays, hotels, restaurants and bars shut etc.

Which is partly ongoing the reduction of aerosols and the effects will be continuing for a long time if activity/jobs/travel/consumption/tourism is reduced into next year.

The International Air Transport Association said it did not expect 2019 levels to be exceeded until 2023.

https://www.breakingtravelnews.com/news/article/no-full-aviation-recovery-until-at-least-2023-iata-predicts/

Some 1.3 million passengers flew into the UK last month compared with 11.1 million in July 2019, the Home Office said.

https://www.msn.com/en-gb/news/uknews/flight-arrivals-down-89-in-july-despite-travel-corridors/ar-BB18qjfm

Researchers around the world are now trying to parse out how Coronavirus lockdown measures have affected global emissions. In the Nature Climate Change study published last month, an international team of scientists found that daily CO2 emissions dropped by 17% at the peak of the coronavirus shutdown.

Another study published in Geophysical Research Letters in May found that nitrogen dioxide pollution over China, Western Europe and the United States decreased by as much as 60% in early 2020 compared to the same time last year. And a study focused on northern China found that levels of particulate matter known as PM 2.5, a notable human health hazard, decreased by approximately 60 percent in January and February.

https://insideclimatenews.org/news/08062020/sulfate-emissions-coronavirus-arctic-heatwaves

The COVID-19 pandemic elicited a global response to limit associated mortality, with social distancing and lockdowns being imposed. In India, human activities were restricted from late March 2020. This ‘anthropogenic emissions switch-off’ presented an opportunity to investigate impacts of COVID-19 mitigation measures on ambient air quality in five Indian cities (Chennai, Delhi, Hyderabad, Kolkata, and Mumbai), using in-situ measurements from 2015 to 2020. For each year, we isolated, analysed and compared fine particulate matter (PM2.5) concentration data from 25 March to 11 May, to elucidate the effects of the lockdown. Like other global cities, we observed substantial reductions in PM2.5 concentrations, from 19 to 43% (Chennai), 41–53% (Delhi), 26–54% (Hyderabad), 24–36% (Kolkata), and 10–39% (Mumbai). Generally, cities with larger traffic volumes showed greater reductions. Aerosol loading decreased by 29% (Chennai), 11% (Delhi), 4% (Kolkata), and 1% (Mumbai) against 2019 data.

https://www.sciencedirect.com/science/article/pii/S221067072030603X

Concentrations of sulfur dioxide in polluted areas in India have decreased by around 40% between April 2019 and April 2020. Using data from the Copernicus Sentinel-5P satellite, from the European Union Copernicus program, scientists have produced new maps that show the drop in concentrations across the country in times of COVID-19.

https://scitechdaily.com/sulfur-dioxide-concentrations-drop-over-india-during-covid-19/

https://www.sciencedaily.com/releases/2020/07/200709141538.htm

"We are experiencing the worst economic shock since the Great Depression, while at the same time we have experienced the greatest drop in greenhouse gas emissions since the burning of fossil fuels began," Dr Malik said.

This study focuses on 'live' data to 22 May (with the exception of air travel, for which only a 12-month forecast exists), differing from most assessments of the economic impacts of the pandemic based on scenario analyses and/or projections -- and it is the first to provide an overview of the combined economic, social and environmental impacts, including indirect effects, of the coronavirus.

Key Reductions

    Consumption: US$3.8 trillion (4.2 percent ~ GDP of Germany)
    Jobs: 147m (4.2 percent of the global workforce)
    Income from wages and salaries: $2.1 trillion (6 percent)
    Most directly hit: US, China (mainland), air transport and related tourism
    Greenhouse gas emissions: 2.5Gt (4.6 percent) -- larger than any drop in human history*
    Other atmospheric emissions -- PM2.5: Dangerously fine particulate matter emissions fall 0.6 Mt (3.8 percent); SO2 & NOx: Sulfur dioxide emissions from burning fossil fuels -- which has been linked to asthma and chest tightness -- and emissions from nitrogen oxide -- from fuel combustion, for example, driving cars -- fall 5.1 Mt (2.9 percent).

https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0235654

« Last Edit: August 27, 2020, 11:11:56 PM by glennbuck »

glennbuck

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Re: Global Surface Air Temperatures
« Reply #2258 on: August 27, 2020, 04:36:08 PM »
Aerosol unmasking doesn't explain 2019

Was posting comparison to 2019/2020, would be good if you posted your thoughts here about global dimming and 2020 weather sark, hope you dont mind me using your temperature charts anomaly.

not at all.  I'll point out that we really saw amplified transport to the pole in 2019 with a very large signal at 500mb height anomalies.  anticyclones began flooding to the pole after the sudden final warming of the winter polar vortex.  This split the tropospheric vortex very badly, and we saw continued breakup of the TPV in May - August of 2019.  This period marks the highest 500mb geopotential heights in the record over the North Pole.

Similarly, 2020 had a dynamic final warming of the NH strat PV...

Now the transport is seemingly coming in at a much lower level, as 925mb temperatures have suddenly ripped north of +4C over 4 months.  Unprecedented.

August is looking similar, will wait for the NOAA, Global Climate Report for August. Below is for July.

According to our regional analysis, Europe, Asia, the Caribbean region, and the Gulf of Mexico had their warmest January–July since regional records began in 1910. Europe had a year-to-date temperature departure of +2.10°C (+3.78°F), marking the first time the January–July temperature departure surpassed the 2.0°C (3.6°F) mark on record. This value surpassed the previous record set in 2014 by +0.12°C (+0.22°F). Europe's five warmest January–Julys on record have occurred since 2014.

For Asia, the year-to-date temperature departure of +2.57°C (+4.63°F) surpassed the now second warmest January–July set in 2016 by +0.48°C (0.86°F). Only January–July of 2016 and 2020 have a temperature departure surpassing 2.0°C (3.6°F).

https://www.ncdc.noaa.gov/sotc/global/202007
« Last Edit: August 27, 2020, 08:32:41 PM by glennbuck »

kassy

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Re: Global Surface Air Temperatures
« Reply #2259 on: August 27, 2020, 06:43:34 PM »
As we saw this year people just love seeing a pattern even when there is none or not one you could easily see.

Looking at an anomaly map that gives us current temps vs a certain base line and then relating that to some recent ´Covid´effect from this year is not going to work.

What we don´t know:
How much of our current anomaly can be related to natural variability?

How much of our current anomaly can be related to AGW?

And we don´t know the exact amount of change. Numbers on CO2 and NOx have been provided, haven´t seen one for drop out of masking aerosols. So it makes it hard to even start guessing.

Basically all these claims stem from the fallacy of people seeing patterns that are probably not there.

Now these polar anomalies are something else. Keep reporting on them sark. 
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Lewis

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Re: Global Surface Air Temperatures
« Reply #2260 on: September 07, 2020, 05:17:02 PM »
August 2020 was the fourth warmest August on record according to Copernicus.

At 0.44C above the August 1981-2010 average globally
Behind 2016 (+0.58C) (cooler by 0.13C)
Behind 2019 (+0.53C) (cooler by 0.09C)
Behind 2017 (+0.47C) (cooler by 0.03C)

https://climate.copernicus.eu/surface-air-temperature-august-2020

kassy

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Re: Global Surface Air Temperatures
« Reply #2261 on: October 01, 2020, 09:44:39 AM »
Climate change heating up nights faster than days, study finds

...

Scientists at the University of Exeter set out to find answers to these questions, turning to hourly records of temperature, cloud cover, specific humidity and precipitation to gauge the differences between nighttime and daytime temperature increases. This modeling was applied to the period of warming between 1983 and 2017, in which the team uncovered a difference in the mean annual temperature of more than 0.25 °C (0.45 °F) between night and day across more than half of the world’s land surface.

While in some locations days were seen to warm more quickly, the total area of regions experiencing greater nighttime warming was more than two times larger. According to the team, this asymmetrical warming phenomenon is being largely driven by shifts in cloud cover, with increased coverage helping to keep the land cool in the day and locking the warmth in at night. The opposite was true in places with decreased cloud cover, which led to faster-warming days.

...

https://newatlas.com/environment/climate-change-nights-faster-days-study/


Global variation in diurnal asymmetry in temperature, cloud cover, specific humidity and precipitation and its association with leaf area index (OA)

https://onlinelibrary.wiley.com/doi/10.1111/gcb.15336

This not a new find but a newer more detailed study.
Þetta minnismerki er til vitnis um að við vitum hvað er að gerast og hvað þarf að gera. Aðeins þú veist hvort við gerðum eitthvað.

kassy

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Re: Global Surface Air Temperatures
« Reply #2262 on: October 07, 2020, 11:41:31 AM »
September was world's 'hottest on record'

September was the warmest on record globally, according to the weather service Copernicus.

It was 0.05C hotter than September last year, which in turn set the previous record high for the month.

...

This year is also projected to become the warmest on record for Europe, even if temperatures cool somewhat from now on.

The elevated heat globally contributed to record wildfires in California and Australia.

It also helped fuel the hottest day on record - a searing 54.4C (130F) in Death Valley.

https://www.bbc.com/news/science-environment-54442782
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vox_mundi

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Re: Global Surface Air Temperatures
« Reply #2263 on: October 07, 2020, 08:00:26 PM »
September Was World's 'Hottest On Record'
https://www.bbc.com/news/amp/science-environment-54442782

“There are three classes of people: those who see. Those who see when they are shown. Those who do not see.” ― Leonardo da Vinci

Insensible before the wave so soon released by callous fate. Affected most, they understand the least, and understanding, when it comes, invariably arrives too late

vox_mundi

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Re: Global Surface Air Temperatures
« Reply #2264 on: October 15, 2020, 06:28:55 PM »
Earth Just Had Its Hottest September On Record
https://phys.org/news/2020-10-earth-hottest-september.html



Unprecedented heat around the world vaulted September 2020 to the hottest September since 1880, according to scientists at NOAA's National Centers for Environmental Information.

The month's warmth also contributed to 2020's trend as a remarkably hot year, with the year-to-date global temperatures running second highest in the 141-year climate record.

The average global temperature in September was 1.75 degrees F—0.97 of a degree C—above the 20th-century average of 59.0 degrees F (15.0 degrees C).

The 10-warmest Septembers have all occurred since 2005, with the seven-warmest Septembers occurring in the last seven years. (... I see a trend ...)
“There are three classes of people: those who see. Those who see when they are shown. Those who do not see.” ― Leonardo da Vinci

Insensible before the wave so soon released by callous fate. Affected most, they understand the least, and understanding, when it comes, invariably arrives too late

Shared Humanity

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Re: Global Surface Air Temperatures
« Reply #2265 on: October 16, 2020, 01:25:12 AM »
The 10-warmest Septembers have all occurred since 2005, with the seven-warmest Septembers occurring in the last seven years. (... I see a trend ...)

This would seem to be the case.

Tor Bejnar

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Re: Global Surface Air Temperatures
« Reply #2266 on: October 16, 2020, 04:55:49 AM »
Yup, Donald Trump just has to have the best, biggest, most huge temperatures ever during the autumn of his presidency.  And his influence goes all over the world, his ego being so inflamed.
 :-\ :'( :P
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rboyd

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Re: Global Surface Air Temperatures
« Reply #2267 on: October 17, 2020, 02:00:42 AM »
NASA-GISS September Global Temperature Details

September is 1.02C above 1951-1980 average
- 1.28C above "pre-industrial" level
- 1.48C above pre-1750 levels

The first nine months of the year are 1.05C above 1951-1980 average
- 1.30C above "pre-industrial" level
- 1.50C above pre-1750 levels

First nine months are also 0.03C above the full year number for 2016 (the current yearly peak), so odds are that 2020 will set a new yearly peak temperature - only 4 years to surpass the El Nino boosted 2016 (and we are in a mild La Nina - see 2020 ENSO thread).

BornFromTheVoid

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Re: Global Surface Air Temperatures
« Reply #2268 on: November 06, 2020, 11:16:19 AM »
3rd warmest October on record according to the Copernicus data.
Also, 81 months since we've had a month outside of the top 5 warmest for their respective month (last was February 2014).

https://climate.copernicus.eu/surface-air-temperature-october-2020
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grixm

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Re: Global Surface Air Temperatures
« Reply #2269 on: December 07, 2020, 08:16:42 AM »
Quote
Globally, November 2020 was the warmest November on record, by a clear margin.

https://climate.copernicus.eu/surface-air-temperature-november-2020

El Cid

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Re: Global Surface Air Temperatures
« Reply #2270 on: December 07, 2020, 12:51:58 PM »
Looking at the copernicus chart, most, or a good portion of that anomaly comes from Siberia, which is itself casued by the anomalously open siberian seas

Yuha

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Re: Global Surface Air Temperatures
« Reply #2271 on: December 08, 2020, 11:39:31 AM »
Quote
Globally, November 2020 was the warmest November on record, by a clear margin.

https://climate.copernicus.eu/surface-air-temperature-november-2020

Nick Stokes is reporting a very warm, though not record warm November:

https://moyhu.blogspot.com/2020/12/november-global-surface-templs-up-0188.html

Nasa GISS November data is not out yet but Jan-Oct was at +1.033C, just behind the record year 2016 which was at +1.038C through October. Since November and December 2016 were not exceptionally warm (+0.90C and +0.86C), a warm November makes a new record likely. The betting odds are currently at 71.5%:

https://electionbettingodds.com/Climate2020.html

BornFromTheVoid

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Re: Global Surface Air Temperatures
« Reply #2272 on: December 14, 2020, 06:03:56 PM »
NASA GISS data out now. Warmest November on record, crazy heat in the Arctic likely balancing out the weak La Nina
A very high chance that 2020 will be the warmest year now too.
I recently joined the twitter thing, where I post more analysis, pics and animations: @Icy_Samuel

Reginald

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Re: Global Surface Air Temperatures
« Reply #2273 on: December 16, 2020, 02:50:17 PM »
Earth may be even closer to 1.5°C of global warming than we thought

https://www.newscientist.com/article/2262953-earth-may-be-even-closer-to-1-5c-of-global-warming-than-we-thought

Global carbon emissions may have warmed Earth by 18 per cent more than previously thought, raising the prospect of the world having less time than expected to meet the goals of the Paris Agreement and avoid catastrophic climate change.

The global average temperature is thought to have climbed about 1.07°C since the industrial revolution, up from a previous estimate of 0.91°C. This update brings all three of the world’s key temperature data sets in line, suggesting the true temperature rise is at the upper end of previous ranges.

The finding means governments may have less time to curb carbon emissions to hold the temperature rise to 1.5°C or 2°C under the Paris deal, and current estimates of future warming may rise too.

“Climate change hasn’t suddenly got worse. It’s just our estimate of how much warming has taken place has improved,” says Tim Osborn at the University of East Anglia, UK, who today published a paper with Met Office colleagues on the fifth update to the data, known as the Hadley Centre Climatic Research Unit Temperature (HadCRUT5).

[...]

It is notable how closely these three independent data sets now resemble one another, says Kate Marvel at Columbia University, New York, who wasn’t involved in Osborn’s paper.

The change was overdue, say climate scientists. “Honestly, many of us have long recognised that the HadCRUT data set underestimated the warming,” says Michael Mann at Pennsylvania State University.

anthropocene

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Re: Global Surface Air Temperatures
« Reply #2274 on: December 18, 2020, 10:29:49 AM »
Good summary of global temperatures this year and also discussion of impact of aerosols which has been discussed in this thread. Also interesting read on solar cycles and implication for global temperature in the next few years.
Also discussed in this thread was the impact of covid-19 on aerosols and the impact that would have on global temperatures. The graph below would suggest the impact was minimal. Is this because the reduction in aerosols was small and/or for too short a time period? Is there any analysis of this?   
 http://www.columbia.edu/~jeh1/mailings/2020/20201214_GlobalWarmingAcceleration.pdf
« Last Edit: December 18, 2020, 10:35:20 AM by anthropocene »

Tor Bejnar

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Re: Global Surface Air Temperatures
« Reply #2275 on: December 18, 2020, 01:50:08 PM »
What's the refrain?
Evidence of global warming includes "Nights warming faster than days; winters warming faster than summers."
Does that graph show it? (If it was a NH graph [only] it would be showing it, but we have winter and summer at the same time every year, only in different places)

Interesting:  2016 set or tied 6 monthly records.  2020 has set or tied 6 monthly records (so far).
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vox_mundi

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Re: Global Surface Air Temperatures
« Reply #2276 on: December 22, 2020, 12:15:40 AM »
Threshold for Dangerous Climate Warming Will Likely Be Crossed Between 2027–2042
https://phys.org/news/2020-12-threshold-dangerous-climate.html

The threshold for dangerous global warming will likely be crossed between 2027 and 2042—a much narrower window than the Intergovernmental Panel on Climate Change's estimate of between now and 2052. In a study published in Climate Dynamics, researchers from McGill University introduce a new and more precise way to project the Earth's temperature. Based on historical data, it considerably reduces uncertainties compared to previous approaches.

... Until now, wide ranges in overall temperature projections have made it difficult to pinpoint outcomes in different mitigation scenarios. For instance, if atmospheric CO2 concentrations are doubled, the General Circulation Models (GCMs) used by the Intergovernmental Panel on Climate Change (IPCC), predict a very likely global average temperature increase between 1.9 and 4.5C—a vast range covering moderate climate changes on the lower end, and catastrophic ones on the other.

"Our new approach to projecting the Earth's temperature is based on historical climate data, rather than the theoretical relationships that are imperfectly captured by the GCMs. Our approach allows climate sensitivity and its uncertainty to be estimated from direct observations with few assumptions," says co-author Raphael Hebert, a former graduate researcher at McGill University, now working at the Alfred-Wegener-Institut in Potsdam, Germany.

In a study for Climate Dynamics, the researchers introduced the new Scaling Climate Response Function (SCRF) model to project the Earth's temperature to 2100. Grounded on historical data, it reduces prediction uncertainties by about half, compared to the approach currently used by the IPCC. In analyzing the results, the researchers found that the threshold for dangerous warming (+1.5C) will likely be crossed between 2027 and 2042. This is a much narrower window than GCMs estimates of between now and 2052. On average, the researchers also found that expected warming was a little lower, by about 10 to 15 percent. They also found, however, that the "very likely warming ranges" of the SCRF were within those of the GCMs, giving the latter support.

Raphaël Hébert et al, An observation-based scaling model for climate sensitivity estimates and global projections to 2100, Climate Dynamics (2020)
https://link.springer.com/article/10.1007/s00382-020-05521-x

Abstract: ... Projecting to 2100, we find that to keep the warming below 1.5 K, future emissions must undergo cuts similar to RCP 2.6 for which the probability to remain under 1.5 K is 48 %. RCP 4.5 and RCP 8.5-like futures overshoot with very high probability
« Last Edit: December 22, 2020, 12:57:13 PM by vox_mundi »
“There are three classes of people: those who see. Those who see when they are shown. Those who do not see.” ― Leonardo da Vinci

Insensible before the wave so soon released by callous fate. Affected most, they understand the least, and understanding, when it comes, invariably arrives too late

wolfpack513

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Re: Global Surface Air Temperatures
« Reply #2277 on: December 24, 2020, 09:43:23 AM »
The graph below would suggest the impact was minimal. Is this because the reduction in aerosols was small and/or for too short a time period? Is there any analysis of this?   
 http://www.columbia.edu/~jeh1/mailings/2020/20201214_GlobalWarmingAcceleration.pdf

Why would this graph suggest this?  2015-2016 was the strongest El Niño in modern history and 2019-2020 was barely a threshold weak El Niño.  I would say that this chart tells me the opposite. 

anthropocene

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Re: Global Surface Air Temperatures
« Reply #2278 on: January 05, 2021, 12:26:32 AM »
The graph below would suggest the impact was minimal. Is this because the reduction in aerosols was small and/or for too short a time period? Is there any analysis of this?   
 http://www.columbia.edu/~jeh1/mailings/2020/20201214_GlobalWarmingAcceleration.pdf

Why would this graph suggest this?  2015-2016 was the strongest El Niño in modern history and 2019-2020 was barely a threshold weak El Niño.  I would say that this chart tells me the opposite. 

I could have phrased that better. It's more of a question: Is it possible to determine a signal of lower aerosols from the temp graph from 2020? The main problem is that we do not have direct measurement of the level of aerosols and their effect on incoming and out-going radiation. A point Hansen has made many times. So (from the graph) it could be inferred that possible lower aerosol amounts in the atmosphere contributed to higher temperatures in the March to June(?) period but with no direct record of when the reduction of aerosols happened and by how much it's just hand-waving. And then the November measurement has to be explained.

Summary of the Hansen and Sato paper (and later in the podcast repeat of counter research)  and discussion of aerosols is in EcoShock podcast episode: https://www.ecoshock.org/2020/12/global-warming-acceleration-hansen-sato.html 



grixm

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Re: Global Surface Air Temperatures
« Reply #2279 on: January 07, 2021, 10:21:57 AM »
Looks like it's going to be a nailbiter as to whether 2020 officially beat the record: https://moyhu.blogspot.com/2021/01/templs-global-surface-2020-just-cooler.html

Hefaistos

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Re: Global Surface Air Temperatures
« Reply #2280 on: January 07, 2021, 11:11:57 AM »
Looks like it's going to be a nailbiter as to whether 2020 officially beat the record: https://moyhu.blogspot.com/2021/01/templs-global-surface-2020-just-cooler.html

Also the UAHv6 get the same result: 2020 ended as the 2nd warmest year in the 42-year satellite lower tropospheric temperature record at +0.49 deg. C, behind the 2016 value of +0.53 deg. C.

https://www.nsstc.uah.edu/data/msu/v6.0beta/tlt/uahncdc_lt_6.0beta5.txt
https://www.nsstc.uah.edu/climate/

grixm

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Re: Global Surface Air Temperatures
« Reply #2281 on: January 08, 2021, 08:49:53 AM »
Similar results from Copernicus: https://climate.copernicus.eu/surface-air-temperature-december-2020

Quote
The calendar-year average for 2020 was on a par with that for 2016, with 2020 cooler than 2016 by less than 0.01°C, well below the spread among multiple datasets.


grixm

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Re: Global Surface Air Temperatures
« Reply #2282 on: January 18, 2021, 08:31:35 AM »
And finally NASA has declared their result, which is a tie for warmest year (1.02 C above baseline)

https://data.giss.nasa.gov/gistemp/maps/index_v4.html
https://www.giss.nasa.gov/research/news/20210114/

Hefaistos

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Re: Global Surface Air Temperatures
« Reply #2283 on: January 18, 2021, 09:04:37 AM »
2021 is likely to be cooler than 2016 and 2020, due to
1. Negative ENSO (La Nina) for most of 2021
2. Solar minimum.

Might we call another global warming hiatus?

KiwiGriff

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Re: Global Surface Air Temperatures
« Reply #2284 on: January 18, 2021, 10:02:16 AM »
Quote
Might we call another global warming hiatus?

You could.
But you would just be confirming  you are a scientifically illiterate denier of reality .

For those of us with some idea .
Interesting new post on real climate looking at the last years global temperatures including the influence  of  ENSO
   http://www.realclimate.org/index.php/archives/2021/01/2020-hindsight/
Animals can be driven crazy by placing too many in too small a pen. Homo sapiens is the only animal that voluntarily does this to himself.
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wolfpack513

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Re: Global Surface Air Temperatures
« Reply #2285 on: January 18, 2021, 02:49:35 PM »
Any smooth less than 15-20 years is highly influenced by internal variability of the climate system.  The horse race coverage of the ups and downs in year-to-year global T's is mostly ENSO, eruptions, etc..  Decadal warming remains fairly stable at +0.20°C per decade.

Hefaistos

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Re: Global Surface Air Temperatures
« Reply #2286 on: January 19, 2021, 06:21:30 AM »
Any smooth less than 15-20 years is highly influenced by internal variability of the climate system.  The horse race coverage of the ups and downs in year-to-year global T's is mostly ENSO, eruptions, etc..  Decadal warming remains fairly stable at +0.20°C per decade.

Yes, you can smooth away any variability you want!
The long-term trend includes various hiatuses. Some longer, some shorter.
I'm just saying that we might be in one of those hiatuses now, whether we're "illiterate deniers of reality" or not.

oren

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Re: Global Surface Air Temperatures
« Reply #2287 on: January 19, 2021, 10:57:24 AM »
So, by hiatus do you mean that global warming has actually stalled / will actually stall? Or do you mean there was a year so far above the trend thanks to a monster El Nino that the years after that do not exceed it for some time, especially with frequent La Ninas? I have a sinking feeling you mean the second definition, which is meaningless except in the eyes of deniers. We had our share of such a false hiatus and widespread denier claims in the years after 1998, while AGW was marching on stronger than ever.

Rodius

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Re: Global Surface Air Temperatures
« Reply #2288 on: January 19, 2021, 11:33:00 AM »
2016 may be still number one, but then it did have the El Nino helping it up.
2020 had nothing like that and a La Nina coming in toward the end of the year.

Given this info, 2020 is worse..... and when the next El Nino comes along, there will be another leap upward.

El Cid

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Re: Global Surface Air Temperatures
« Reply #2289 on: January 19, 2021, 02:08:06 PM »
..... and when the next El Nino comes along, there will be another leap upward.

The Great Leap Forward. Sounds bad. The last one cost 50 million lives...

Shared Humanity

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Re: Global Surface Air Temperatures
« Reply #2290 on: January 19, 2021, 08:31:03 PM »
So, by hiatus do you mean that global warming has actually stalled / will actually stall? Or do you mean there was a year so far above the trend thanks to a monster El Nino that the years after that do not exceed it for some time, especially with frequent La Ninas? I have a sinking feeling you mean the second definition, which is meaningless except in the eyes of deniers. We had our share of such a false hiatus and widespread denier claims in the years after 1998, while AGW was marching on stronger than ever.

Exactly. The very high temperatures in 1998 allowed global warming deniers the opportunity to claim for more than a decade the warming had stopped. The new record in 2016 will allow them to do the same. Meanwhile, temperatures keep rising.

Hefaistos

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Re: Global Surface Air Temperatures
« Reply #2291 on: January 20, 2021, 08:25:52 AM »
I'm not denying anything here, i'm just saying that the long-term global warming trend of about 0.14 K per decade (since satellite data started around 1980) includes a lot of natural variability, also hiatuses of shorter or longer duration. A hiatus w. 10 years duration would be seen as a long one.

I'm really interested in the natural variability going on mainly in the oceans. ENSO is important, but for the longer terms we shouldn't forget about PDO (negative since 5 years) and AMO.

It's not unlikely we might get a hiatus of , let's guess, 10 years since 2016. 2021 is highly likely to be cooler than 2020, and 2022 as well, due to various natural factors. Then, it's anyones guess when we'll get another strong El Nino that will break the hiatus.
« Last Edit: January 20, 2021, 08:32:56 AM by Hefaistos »

KiwiGriff

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Re: Global Surface Air Temperatures
« Reply #2292 on: January 20, 2021, 06:47:29 PM »
Claims to be not a denier.
Cherry picks one outlaying data set.
Only UHA gives 0.14.
All the others give 0.19C a decade or more.
https://skepticalscience.com/trend.php
Still claims we can have a hiatus in warming by looking at  noise.
It is the trend stupid .
Global warming  is the long term trend not the yearly weather fluctuations.
Animals can be driven crazy by placing too many in too small a pen. Homo sapiens is the only animal that voluntarily does this to himself.
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The Walrus

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Re: Global Surface Air Temperatures
« Reply #2293 on: January 20, 2021, 08:16:46 PM »
Claims to be not a denier.
Cherry picks one outlaying data set.
Only UHA gives 0.14.
All the others give 0.19C a decade or more.
https://skepticalscience.com/trend.php
Still claims we can have a hiatus in warming by looking at  noise.
It is the trend stupid .
Global warming  is the long term trend not the yearly weather fluctuations.

Funny how you criticize someone for choosing one dataset, when you are doing the same.  From your link are the following:

HadCRUT:  0.173 C / decade
NOAA:        0.168 C / decade
RSSv4.0      0.174 C / decade

The only temperature trend in your region was GISTEMPv4 at 0.189 C / decade (rounded to 0.19, but definitely not over).  UAH was actually 0.132 C / decade.  I though a denier was someone who actually denied that warming was occurring, not nitpicking a few tenth of a degree.

WildFit

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Re: Global Surface Air Temperatures
« Reply #2294 on: January 20, 2021, 10:11:18 PM »
For me there are 2 main levels of denial:

a) as it was mentioned, those who deny AGW is happening

b) those who admit it's happening but deny that humanity is the cause or at least has a significant impact.

I say, that it's happening is a scientific fact, that it's man made is a statistical fact but then I refuse to accept that anyone knows that AGW is just bad. Looking back in history the fastest and most diverse development of live on planet earth was during stable warmer than now periods.

It will be horrible (fatal) for too many, yes, but then the planet (nature) will find a regulative for our abuse of resources either way and if it's simply to reduce population to a sustainable level.

Unfortunately those who promote that we have to protect everything and everyone against the consequence of our sheer existence in actual numbers are the same who would fight any natural regulative because they claim that humans are the crown of creation (or similar claims and attitudes) while I believe that we are nothing in the big picture of our univers and eventual multiverses and that we are prone to according processes and developments either way, no matter what we do. We can only influence moments and manners but not the fact of certain natural circles themselves.

So much of the shown exitement is ego-based self-profiling and a certain amount of calmness and pragmatism would be very helpful to avoid all the bickering and add-hominem stuff all around the world.
« Last Edit: January 20, 2021, 10:16:54 PM by WildFit »

oren

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Re: Global Surface Air Temperatures
« Reply #2295 on: January 21, 2021, 02:46:10 AM »
This is going off-topic.

Hefaistos

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Re: Global Surface Air Temperatures
« Reply #2296 on: January 21, 2021, 03:47:07 AM »
Claims to be not a denier.
Cherry picks one outlaying data set.
Only UHA gives 0.14.
All the others give 0.19C a decade or more.
https://skepticalscience.com/trend.php
Still claims we can have a hiatus in warming by looking at  noise.
It is the trend stupid .
Global warming  is the long term trend not the yearly weather fluctuations.

Here's a graph comparing the various datasets for the period from 2014, All series are in general agreement, as they show the same patterns and trend, and we can see the developing hiatus.
Will be interesting to follow in the coming years!


Funny how you criticize someone for choosing one dataset, when you are doing the same.  From your link are the following:

HadCRUT:  0.173 C / decade
NOAA:        0.168 C / decade
RSSv4.0      0.174 C / decade

The only temperature trend in your region was GISTEMPv4 at 0.189 C / decade (rounded to 0.19, but definitely not over).  UAH was actually 0.132 C / decade.  I though a denier was someone who actually denied that warming was occurring, not nitpicking a few tenth of a degree.

Here's a graph comparing the various datasets for the period from 2014, All series are in general agreement, as they show the same patterns and trend, and we can see the developing hiatus.
Will be interesting to follow in the coming years!

oren

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Re: Global Surface Air Temperatures
« Reply #2297 on: January 21, 2021, 04:11:36 AM »
Are you sure this is not taken from another denier website by any chance?

To the matter at hand, what can be seen is a monster ENSO spike on top of a rising trend.
« Last Edit: January 21, 2021, 04:17:35 AM by oren »

Rodius

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Re: Global Surface Air Temperatures
« Reply #2298 on: January 21, 2021, 04:24:17 AM »
That graph looks like cherry picking to me.

Looking at the trend (as much as can be done in a 7 year snap shot, it looks like the temps have increased from about 0.2C to 0.5C, which a trend upwards.

Also, there appears to be a relatively clear increase between 2015 and 2017, with ENSO being 2016.

All of this lends itself to the increases per decade that have been detailed previously.

KiwiGriff

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Re: Global Surface Air Temperatures
« Reply #2299 on: January 21, 2021, 07:34:12 AM »
His source is here .
https://oz4caster.wordpress.com/monthly-trends/
(right click on an image and google search will find a source )
From the same page as the image .
Quote
The pattern of temperature trends for the Southern Hemisphere middle latitudes and Antarctic is not consistent with hypothesized significant man-made global warming.  Since carbon dioxide concentrations are relatively uniform across the globe on a time scale of years and show persistent upward trends since 1979, these flat and downward temperature trends indicate that hypothesized man-made global warming is not dominant and that other factors are likely to be more dominant over the last 40 years.  The implication is that observed upward temperature trends in the Northern Hemisphere are also being dominated by other factors.  These other factors need to be resolved before any kind of accurate future climate predictions can be made.  Predictions made assuming that man-made global warming is dominant are likely to fail.
It is a denial blog.

As to Walrus
If you want to include all of 2020 at the sk sc trend calculator you must use an end date of 2021.
 The question is global temperature trends  so I did not consider the other series with less than global coverage. RSS TTT is biased by stratospheric contamination so is not useful for  discerning the trend in global warming.
I only used the most up to date versions in all cases .1980 to 2021.
https://skepticalscience.com/trend.php
GISTEMPv4 Trend: 0.193 ±0.040 °C/decade (2σ)
Berkeley Trend: 0.192 ±0.033 °C/decade (2σ)
HadCRUT4krig v2 Trend: 0.192 ±0.035 °C/decade (2σ)
with HadSST4 Trend: 0.188 ±0.036 °C/decade (2σ)

RSSv4.0 TLT Trend: 0.218 ±0.056 °C/decade (2σ)

The out layer is Dr Roys UAH.
UAHv6.0 TLT Trend: 0.138 ±0.056 °C/decade (2σ)

« Last Edit: January 21, 2021, 08:04:22 AM by KiwiGriff »
Animals can be driven crazy by placing too many in too small a pen. Homo sapiens is the only animal that voluntarily does this to himself.
Notebooks of Lazarus Long.
Robert Heinlein.