ETH Zurich
In October this year, weather researchers in Utah measured the lowest temperature ever recorded in the month of October in the US (excluding Alaska): -37.1°C. The previous low-temperature record for October was -35°C, and people wondered what had happened to climate change.
Until now, climate researchers have responded that climate is not the same thing as weather. Climate is what we expect in the long term, whereas weather is what we get in the short term – and since local weather conditions are highly variable, it can be very cold in one location for a short time despite long-term global warming. In short, the variability of local weather masks long-term trends in global climate.
A paradigm shift
Now, however, a group led by ETH professor Reto Knutti has conducted a new analysis of temperature measurements and models. The scientists concluded that the weather-is-not-climate paradigm is no longer applicable in that form. According to the researchers, the climate signal – that is, the long-term warming trend – can actually be discerned in daily weather data, such as surface air temperature and humidity, provided that global spatial patterns are taken into account.
In plain English, this means that – despite global warming – there may well be a record low temperature in October in the US. If it is simultaneously warmer than average in other regions, however, this deviation is almost completely eliminated. “Uncovering the climate change signal in daily weather conditions calls for a global perspective, not a regional one,” says Sebastian Sippel, a postdoc working in Knutti’s research group and lead author of a study recently published in Nature Climate Change.
Statistical learning techniques extract climate change signature
In order to detect the climate signal in daily weather records, Sippel and his colleagues used statistical learning techniques to combine simulations with climate models and data from measuring stations. Statistical learning techniques can extract a “fingerprint” of climate change from the combination of temperatures of various regions and the ratio of expected warming and variability. By systematically evaluating the model simulations, they can identify the climate fingerprint in the global measurement data on any single day since spring 2012.
A comparison of the variability of local and global daily mean temperatures shows why the global perspective is important. Whereas locally measured daily mean temperatures can fluctuate widely (even after the seasonal cycle is removed), global daily mean values show a very narrow range.
If the distribution of global daily mean values from 1951 to 1980 are then compared with those from 2009 to 2018, the two distributions (bell curves) barely overlap. The climate signal is thus prominent in the global values but obscured in the local values, since the distribution of daily mean values overlaps quite considerably in the two periods.
Application to the hydrological cycle
The findings could have broad implications for climate science. “Weather at the global level carries important information about climate,” says Knutti. “This information could, for example, be used for further studies that quantify changes in the probability of extreme weather events, such as regional cold spells. These studies are based on model calculations, and our approach could then provide a global context of the climate change fingerprint in observations made during regional cold spells of this kind. This gives rise to new opportunities for the communication of regional weather events against the backdrop of global warming.”
The study stems from a collaboration between ETH researchers and the Swiss Data Science Center (SDSC), which ETH Zurich operates jointly with its sister university EPFL. “The current study underlines how useful data science methods are in clarifying environmental questions, and the SDSC is of great use in this,” says Knutti. Data science methods not only allow researchers to demonstrate the strength of the human “fingerprint”, they also show where in the world climate change is particularly clear and recognisable at an early stage. This is very important in the hydrological cycle, where there are very large natural fluctuations from day to day and year to year. “In future, we should therefore be able to pick out human-induced patterns and trends in other more complex measurement parameters, such as precipitation, that are hard to detect using traditional statistics,” says the ETH professor.
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Reference
Sippel S, Meinshausen N, Fischer EM, Székely E, Knutti R: Climate change now detectable from any single day of weather at global scale. Nature Climate Change 2019, 2 January, DOI: 10.1038/s41558-019-0666-7
“Uncovering the climate change signal in daily weather conditions calls for a global perspective, not a regional one,”
Regional temp changes, especially in populated crop growing areas during planting/harvesting periods (or populated cold areas with fuel poverty) are the ONLY important conditions. “Global” changes mean squat.
It’s not long ago, in the time of hiatus, they told us, global climate is for human beings not so important than regionl / local climate, there, where people lives…
Good comment BFL.
Planting was one month late due to cold Spring weather across the Great Plains of North America in both 2018 and 2019.
Summer was warm in 2018 and produced a good crop.
In 2019 Spring was wet and cold and ~40% of the huge USA corn crop was not planted. Summer 2019 was cold and snow came early in the Fall, and the crop was a failure across much of the Great Plains. This mattered a lot, locally.
The South had a good harvest and there was lots of grain in storage, so prices were stable.
https://wattsupwiththat.com/2019/12/22/solar-update-december-2019/#comment-2876970
Comments from Sept2002, June2018, June2019 and Oct-to-Dec2019 re cooling:
https://wattsupwiththat.com/2018/06/why-some-climate-advocates-shouldnt-have-twitter-access/#comment-2368062
[excerpt]
Crop planting is about one month late across the prairies and there may even still be snow on the ground in the woods.
https://wattsupwiththat.com/2019/06/23/the-setup-is-like-1315/#comment-2730429
Last week, my friend Joe D’Aleo and I discussed the late planting in the USA grain belt. Planting occurred about one month late last year as well, but an excellent summer led to a good crop. This year the crop situation is more worrisome.
Here in Alberta, it feels colder, like the Winters and Springs of several decades ago.
Told you so , 17 years ago.
“CO2, Global Warming, Climate and Energy”
by Allan M.R. MacRae, B.A.Sc., M.Eng. June 2019
pdf: https://thsresearch.files.wordpress.com/2019/06/co2-global-warming-climate-and-energy-june2019-final-.pdf
Excel spreadsheet: https://thsresearch.files.wordpress.com/2019/06/co2-global-warming-climate-and-energy-june2019-final.xlsx
10. I wrote in an article published 1Sept2002 in the Calgary Herald:
“If [as we believe] solar activity is the main driver of surface temperature rather than CO2, we should begin the next cooling period by 2020 to 2030.”
I will stand with this prediction – for moderate, natural cooling, similar to that which occurred from ~1940 to the Great Pacific Climate Shift of 1977, despite accelerating fossil fuel combustion and atmospheric CO2. Similar cooling occurred from ~1945 to 1977 as fossil fuel consumption accelerated.
I now think global cooling will start closer to 2020. The following plot explains why (Fig.10).
I hope to be wrong, because humanity and the environment suffer during cold periods.
Fig.10 – Apparent Coherence of Total Solar Irradiance, Sea Surface Temperature and Lower Tropospheric Temperature, interrupted by the 1998 El Nino
http://woodfortrees.org/plot/pmod/offset:-1360/scale:0.2/plot/hadsst3gl/from:1980/plot/uah6/from:1980
Regards, Allan
_________________________
https://wattsupwiththat.com/2019/12/16/its-official-we-are-in-a-deep-solar-minimum/#comment-2872906
See details in these two papers:
There were good harvests in the USA SE and South in 2019, and lots of grain in storage so prices did not escalate – but there were big crop losses across the Great Plains. Also lots of that grain will be feed grade only, if they do get it off the fields.
“The Real Climate Crisis Is Not Global Warming, It Is Cooling, And It May Have Already Started”
By Allan M.R. MacRae and Joseph D’Aleo, October 27, 2019
https://wattsupwiththat.com/2019/10/27/the-real-climate-crisis-is-not-global-warming-it-is-cooling-and-it-may-have-already-started/
“Growing Season Challenges From Start To Finish”
By Joseph D’Aleo, CCM, AMS Fellow, Co–‐chief Meteorologist at Weatherbell.com, Nov 18, 2019
https://thsresearch.files.wordpress.com/2019/11/growing-season-challenges-from-start-to-finish.pdf
“Your card was the 🃊! Ta-DAAAA!” I guess the Little Ice Age is really over. But we already knew that. No congratulations are in order. There’s no end to the tricks you can do if you already know the answer.
As far as being able to detect global warming from daily data by the use of novel statistical methods, if that is true, what is the global forecast for tomorrow? Separating annual variation from the mammoth diurnal variation is not a trivial process. “And for my next trick, I will saw this hockey stick in half.”
🃊🃊🃊🃊🃊🃊🃊🃊🃊🃊🃊🃊🃊🃊🃊🃊🃊🃊🃊🃊🃊🃊🃊🃊🃊🃊🃊🃊…
“In future, we should therefore be able to pick out human-induced patterns and trends” says what this ‘study’ was all about.
Until every method ceases to be designed to specifically prove AGW, by researchers who set out with that primary goal, all this conclusion-first research is pretty much done to support/enable/provide propaganda.
When the article started talking about “…machine learning techniques…” I had visions of a nun with ruler in hand standing over a monitor, “Bad! Bad machine! The correct answer is Global Warming! Bad!” *smack*
It always seems that every year is warmer than the last, based on that weather station in the Arctic with the running snow vehicle next to it.
I had to check the header twice when I got a paragraph or two into this article, I thought I had wound up on The Onion by accident.
>>> the climate signal – that is, the long-term warming trend – can actually be discerned in daily weather data, such as surface air temperature and humidity, provided that global spatial patterns are taken into account.
In plain English, this means that – despite global warming – there may well be a record low temperature in October in the US. If it is simultaneously warmer than average in other regions, however, this deviation is almost completely eliminated. <<<
So if it is cold as my ex wife's heart someplace that must be offset by warming elsewhere, but of course it doens’t work the other way: if it is hot in one location that can’t possibly be offset by cold somewhere else, it must be global warming.
There are distinctions here between climate change, CO2 and human involvement. We know climate changes and I agree that changes are best viewed globally. I also agree that it should be using undoctored temperatures that are collected in a consistent manner. A conclusive finding that climate is warming or climate is cooling doesn’t prove that the only cause is CO2, or even that CO2 contributes in the first place. And finally, the mere existence of proof that the climate is changing, and the direction, i.e. hotter or cooler, doesn’t prove human activity is a cause to any degree.
Did they validate the method against another data set not used in the fitting routine?
Climate and weather are two different subjects…climate is only driven by the Sun…not humans or pollution. Weather is locally driven and recently (last 80 years) made worse by technology used by stupid scientists who cow tow to the negative Cabal for funding. Therefore most papers or people like Al Gore and who ever joins the global warming bs are pure evil in action…meaning they lie and lie continuously to keep the lie going. Tim Ball and a few others have proved this beyond a shadow of a doubt in Supreme Court. End of story for the lies. We are headed into a very long ice age. Get over it and get prepared because no government is going to tell you the when the SHTF and what to do about it. You have approximately 2 years before there is no food growth on the planet unless you are prepared. Can not get any simpler a message…get cracking on learning how to survive because this year is the beginning of the Ice packs and the North pole will never be ice free for another 100,000 year cycle. The Northwest Passage has been frozen over for two years now..impossible to pass with ships and ice breakers. You must have heard the news about University students having to be rescued because they were NOT TOLD it was frozen over.!!! Sick lying shills of scientists who would cow tow to this lying to the public.
I guess it’s the principle of the “thin slicing”:
https://en.m.wikipedia.org/wiki/Thin-slicing
OT – I would like to see Willis Eschenbach’s take on the following CERES based study that seems quite important:
https://www.mdpi.com/2072-4292/11/6/663/htm
I think this study touches on an important issue about patterns. I’m beginning to suspect that regional patterns of warm and cold, wet and dry, may be more important than global averages that are unnaturally smeared over different continents. There may be characteristic spatiotemporal global patterns of particular types of climate transition or change.
Even numerologists are rolling their eyes and chuckling.
Steve Macintyre…please help us out here!
Climate researchers unexpected expose the signal of climate research deception.
Obviously, these people are paid too much and/or don’t have much to do.
Gotta look busy! What about if we…..
“In future, we should therefore be able to pick out human-induced patterns and trends in other more complex measurement parameters, such as precipitation, that are hard to detect using traditional statistics,” says the ETH professor. – They’re self-deluded.
Physically what do they mean? You can’t know with their thought system.
Their way claims the ongoing regional variations are simply expected (why? how?) from within a statistical regionally balanced data field, w/o considering net incoming energy changes, just extremes emerging out of the data field that balance out in the end, nothing to see here. In other words, it’s a theory that explains everything without direct attribution to specific forcings for specific events – the latter is what I do in my solar-weather attributions.
It’s warm or cold somewhere for physical reasons, down to physics, not probabilities and regional climate averaging/balancing. Probabilities don’t provide direct attributions, and weather doesn’t cause weather.
If they didn’t know the right attributions before they sure won’t now. The authors’ method has already missed the following real solar attribution from just a few months ago, so why expect them to get anything else right down the road?
The F10.7cm solar flux for a period during October 2019 was the lowest in many decades, perhaps indicating the lowest activity in a century, which was then immediately followed by century-class cold and snow records in the NH. This should inform everyone as to the abruptness of low solar influence in concert with the season. They missed this proper attribution by a mile.
They claim it happened because it was warm somewhere else… statistics made it cold…
Exactly, James! You can and do get a mix of hot places and cool places, but setting all time cold temperatures these past two winters, no, with 150 years of so-called catastrophic Global warming and supposed tripley enhanced polar temperature enhancement on the Arctic. The Illinois all time cold record of -41C+ last winter swooped down from a frigid air mass more than 10 C colder in the Arctic Basin! WUWT?
And a Russian giant icebreaker that took paying passengers ($120,000 a ticket) to the N Pole in August this year ran into continuous ice up to 9m thick as soon as they passed Svalbard. It took 2 days longer each way because the ship had to back up so often (a WUWT article).
Besides, a fingerprint of warming is not automatically a “signal of Anthropo GW” that is one of the most disingenuous assumptions of alarmist science.
“This information could, for example, be used for further studies that quantify changes in the probability of extreme weather events, such as regional cold spells.”
That’s all about short term indirect solar variability driving Arctic Oscillation anomalies, that drives climate change. The occurrence of regional cold spells has nothing to do with probabilities or the mean state of the global climate. Forecast 2019-2020 cold spells. second half of October, second week of November, middle third of December, and late January through February.
https://www.linkedin.com/pulse/2019-2020-cold-season-arctic-oscillation-forecast-ulric-lyons
“climate signals”
They clearly don’t understand math.
Climate is what happens when you put terrain in the way of weather.
The explanation of the statistical method is as follows:
” Statistical detection of externally forced climate change involves three steps. (1) A fingerprint γ^ of external forcing on climate is extracted, using regularized linear regression, that relates model simulated spatial patterns of daily temperatures (Xmod) and a defined univariate target variable used as test statistic (denoted Ymod in the figure: for example annual global mean temperature, AGMT, or decadal-scale Earth’s Energy Imbalance). (2) Spatial patterns of daily temperatures (Xobs) are projected onto the fingerprint γ^ to predict the target variable (denoted Y^obs). (3) A statistical significance test is used to infer whether external forcing on the climate system can be detected from the observed daily temperature pattern against the distribution of the test statistic under natural variability (denoted here P[Y^mod∗]). ”
It seems to be completely dependent on climate models, and thus unable to extract a signal from the noise with as little bias as possible, but only to compare observations with what is supposed to happen given a certain set of assumptions used to build the model(s).
Professor Knutti and his policy-driven “pseudo-science” is going to slowly but surely ruin the ETH’s reputation.
Unfortunately since the Swiss ministry of Environment, Traffic, Energy and Communication (UVEK) has decided to follow Merkel’s footsteps towards the “alternative energy dream”, policy driven science is unfortunately the only way to get research money in Switzerland these days…
Modelled rubbish in = modelled “politically correct” rubbish out.
They used climate models that have no predictive value to assess air temperature measurements that are too inaccurate to resolve any meaningful trend (869.8 KB pdf), in order to deduce a climate effect that is nowhere in evidence.
Such is the incompetence in consensus climatology. Science has long since been betrayed and abandoned there.
Some sixty years ago I was having a technical education and was told that the average for the world was 14.7C@ur momisugly1013 Millibars. I posed the question recently what is the temp of the world now and was told it was 15.1C so for me the world has warmed .4C in about 100 years,very frightening.
I had a career in aircraft and engines were rated for power @ur momisugly 14.7C @ur momisugly1313millibars and probably still are.
I didn’t realize that a “warming signal” was at all controversial – it seems pretty straight forward that the Earth has been warming since the coolest state of the last Ice Age (I guess officially we are still in it) and also since about 1850 since the “Little Ice Age” blip. So detecting that it is warming seems kind of silly?
Now when they mean they can detect the effects of CO2 in the atmosphere – forget it. That is laughable. The data is not of high enough quality to support such a finding, not is our understanding of the atmosphere and its dynamics. They would have to distort and abuse the data in order to demonstrate a biased finding – oh wait, that is already happening. So again, this article is just silly.