Heatwave was triggered by climate change, according to new research

July 30, 2018, University of Oxford
The unprecedented temperatures seen over Summer 2018 are a sign of things to come, and are a direct result of climate change, according to new Oxford University research. Credit: Shutterstock

The unprecedented temperatures seen over Summer 2018 are a sign of things to come—and a direct result of climate change, according to new Oxford University research.

In the newly published report, researchers from the Environmental Change Institute (ECI) at the School of Geography and Environment, Oxford University, who worked in collaboration with the World Weather Attribution network (WWA), reveal that climate change more than doubled the likelihood of the European heatwave, which could come to be known as regular summer temperatures.

Dr. Friederike Otto, Deputy Director of the ECI at the University of Oxford, said: "What was once regarded as unusually warm weather will become commonplace – in some cases, it already has."

The research compares current temperatures with historical records at seven weather stations in northern Europe – two in Finland, one each in Denmark, the Irish Republic, the Netherlands, Norway and Sweden.

These stations were selected because current data could be accessed in real time, and they possess digitised records extending back to the early 1900s. The scientists also used computer models to assess the impact of man-made climate change.

For each year in the historical record, the team looked at the hottest consecutive three-day period. For 2018, it was the hottest three days of the year so far – either observed or in the
short-term forecast.

The findings show that the planet is definitely heating up, and for some of the weather stations, current temperatures are unprecedented in the historical record.

"We found that for the weather in the far north, in the Arctic Circle, the current heat wave is just extraordinary – unprecedented in the historical record," said Dr. Geert Jan van Oldenborgh, Senior Researcher at the Royal Netherlands Meteorological Institute (KNMI).

"And while that is a striking finding, it's hard for us to quantify the increase in likelihood accurately because summer temperatures vary a lot from year to year, making it impossible to estimate the trend from the observations. The same is true for the other three northern stations.

"But for the three stations further south – in the Netherlands, Denmark and Ireland – the historical record does allow us to make a calculation, and it shows that climate change has generally increased the odds of the current heatwave more than two-fold."

The findings show that for the three stations further south – in the Netherlands, Denmark and Ireland climate change has more than doubled the likelihood of the current heatwave. Of these three stations, the one showing the lowest increase in likelihood due to is Dublin, with a factor of 1.2-3.3 and a best estimate of 2. For Copenhagen the odds have increased by a factor 2.4-12, with a best estimate of 5; and for De Bild (Netherlands), 1.6-16, best estimate 3.3. For the four stations further north, observations and models indicate an increase in likelihood, but it has much harder to quantify.

The team stress that the report is based on preliminary analysis, and since it being published before the end of the Summer 2018 heatwave, the definition of the period as an 'extreme event' is based on forecast temperatures – rather than actual quantitative results. These more robust measures can only be collated after the summer has ended. However, the team say the potential environmental and social implications of the findings are undeniable and that action should be taken sooner rather than later.

Dr. Otto explains: 'this is something that society can and should prepare for – but equally there is no doubt that we can and should constrain the increasing likelihood of all kinds of extreme weather events by restricting greenhouse gas emissions as sharply as possible."

The WWA team plans to publish these results formally in a scientific journal. This will form part of a more in-depth analysis of this extraordinary summer; the team will also assess whether climate change played a role in the prolonged high pressure seen in northern Europe since May, and if so, to what extent.

Previous published studies by the group have shown that change increased the chances of the heavy rainfall experienced in northern England in the 2015-16 winter and in Houston due to hurricane Harvey, and that has not changed the likelihood of the 2014 Sao Paolo drought.

Explore further: Heatwaves from the Arctic to Japan: A sign of things to come?

More information: Attribution of the 2018 heat in northern Europe. www.worldweatherattribution.or … -in-northern-europe/

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SamB
2 / 5 (4) Jul 30, 2018
So was that really cold winter last year also triggered by climate change? How about the fairly normal spring we had? Was it too triggered by climate change? How do we know what weather pattern is triggered by climate change?
humy
4.6 / 5 (9) Jul 30, 2018
SamB

You are very confused. Any natural temperature variations would be superimposed on top of the man made general warming trend of global climate thus the likely frequencies of cold snaps down to a given temperature (say, to -30C if that is rare in a particular place) would go down but not to zero frequency and the likely frequencies of heat-waves would go up but not likely to the point where they are continuous i.e. without any break. Thus global warming will not be expected to result in the sudden absence of cold snaps.

One also shouldn't confuse, like you are doing, temporary local temperature extremes (local weather) with average global temperature (global climate). An unusually cold winter in one place doesn't equate with the global temperatures everywhere being lower and there are many examples of when one place got an unusual cold snap while global temperatures were increasing.
gkam
5 / 5 (3) Jul 30, 2018
Go here and look at the graphs of what is actually happening. They are here:

http://www.ipcc.c...ar5/wg1/
Noumenon
1.7 / 5 (6) Jul 30, 2018
So was that really cold winter last year also triggered by climate change? How about the fairly normal spring we had? Was it too triggered by climate change? How do we know what weather pattern is triggered by climate change?


If it is useful in feeding the narrative of AGW-Alarmism, then it was caused by global warming.

One also shouldn't confuse, like you are doing, temporary local temperature extremes (local weather) with average global temperature (global climate).


But Isn't that what the above research is doing (and not SamB),.... referencing a particular "heatwave" and claiming it's on account of AGW, rather than saying it's indicative of what should be expected given increase in global average temp.

humy
4.5 / 5 (8) Jul 30, 2018
But Isn't that what the above research is doing (and not SamB),.... referencing a particular "heatwave" and claiming it's on account of AGW, rather than saying it's indicative of what should be expected given increase in global average temp.
Noumenon

Nope. This is the usual straw man by your hypocritical cult. The research scientists behind this article (and also I) is saying it is indicative.
This article says

"...reveal that climate change more than doubled the likelihood of the European heatwave,"

which clearly implies it is indicative.
While SamB said

"So was that really cold winter last year also triggered by climate change? "

which clearly implies that a local cold snap means global temperatures aren't going up i.e. implying a cold-snap is on account of NO global warming.

Hypocrite.

snoosebaum
1 / 5 (7) Jul 30, 2018
'' The unprecedented temperatures '' good way to start, with a lie
snoosebaum
1 / 5 (7) Jul 30, 2018
lets be thorough, here's the complete list
http://www.number...list.htm
Captain Stumpy
4.4 / 5 (7) Jul 30, 2018
@samb
So was that really cold winter last year also triggered by climate change?
first of all, local weather patterns can definitely be changed to elicit a cold snap during AGW instigated warming as demonstrated by Francis,Vavrus et al

Secondly, not all locations had a colder winter. Global warming has the keyword in it: Global

Thirdly, read Humy's excellent information
How do we know what weather pattern is triggered by climate change?
research, modeling, hypothesis, testing, observation are the keywords there
you can learn a lot starting here: https://skepticalscience.com/

the site breaks down the science in easily readable explanations which use valid reference material
If you don't like that site, you should start by hitting up Google Scholar and reading the science

snoosebaum
1 / 5 (6) Jul 30, 2018
here is our new super hot world today ;

https://earth.nul...7.36,401

looks pretty normal
snoosebaum
1 / 5 (6) Jul 30, 2018
V4Vendicar
5 / 5 (5) Jul 30, 2018
So was that really cold winter last year also triggered by climate change?


What really cold winter? Did you have a cold winter? Is there ice in your ice box? Those are local phenomenon, and you are a moron for conflating your personal observations of your local area, as representative of the entire world.
aksdad
1.7 / 5 (6) Jul 31, 2018
Ha ha haaaa! Climate alarmists calling out skeptics with the don't-confuse-weather-with-climate finger-wagging when the skeptics catch the alarmists blaming recent regional temperatures at a handful of weather stations on "global" warming. That's rich.

Sorry alarmists but you're the ones caught out for confusing weather with climate. You see, if GLOBAL temperatures increase, and stay increased, over a period of several years to decades, that's global warming. When they spike for a few days or weeks or even months at a few REGIONAL weather stations, that's weather. You can't cherry-pick and blame every variable regional climate phenomena on "climate change". Well, you can, but it's idiotic and people see right through it.

Here is the GLOBAL temperature trend, updated monthly:

https://www.nsstc...climate/

Notice that it's been cooling since the large El Niño-caused spike in 2016.

aksdad
1 / 5 (5) Jul 31, 2018
Go here and look at the graphs of what is actually happening

So we're supposed to dig through thousands of pages of .pdf files and hundreds of random images from the 2013 IPCC report to "what is actually happening"?

How about instead we look at the current trends extracted by statistical analysis from the latest temperature data measured by meteorological stations and satellites and updated monthly? For example here:

https://www.nsstc...climate/

http://images.rem...ies.html

Or better yet, see all the current data sets consolidated on one page here:

https://wattsupwi...erature/

But just for fun, let's have a look at Fig. 2-24 from Chapter 2 ("Observations: Atmosphere and Surface") of IPCC AR5 (2013):

http://www.ipcc.c...2-24.jpg

Huh. It clearly shows the global warming "hiatus" that started after the big 1998 El Niño.

howhot3
4.3 / 5 (6) Jul 31, 2018
Facts are facts;
temperatures seen over Summer 2018 are a sign of things to come—and a direct result of climate change


Fact 1. asksdad is troll. Paid troll like we all know. His nonsense is well paid for by the right-wing nimrod party.
Fact 2. aksdad is a nimrod so his words are worth about that much.
But
Fact 3. Nimrod like the russian loving influencers aksdad love horse stuff cuz they site wattsup,,, a lot. And
Fact 5. the Russian troll is on a binge out to waste the country and your one of their follower toodie.
Fact 4. Sad.
unrealone1
1 / 5 (3) Jul 31, 2018
Was warmer 8000 years ago, was warmer 110,000 years ago.
When the Viking graves start melting from there permafrost, then it's getting warmer until them, Umm..
humy
3.7 / 5 (3) Jul 31, 2018
Was warmer 8000 years ago, was warmer 110,000 years ago.
When the Viking graves start melting from there permafrost, then it's getting warmer until them, Umm..
unrealone1

https://en.wikipe...traw_man

gkam
1 / 5 (1) Jul 31, 2018
All this arguing means nothing: It is happening, and we are doing too little to end it.
unrealone1
1 / 5 (1) Jul 31, 2018
Vostok temp records minus 70 degrees, wow that is warm?
https://www.timea...ear=2018
humy
3.7 / 5 (3) Jul 31, 2018
Vostok temp records minus 70 degrees, wow that is warm?
https://www.timea...ear=2018
unrealone1

Are you trying to convince people here that the average global temperature hasn't gone up because of a cold snap in Antarctica?
Sorry, NOBODY here is that stupid as to be convinced by such a moronic argument.
Advice; try to not make yourself look so stupid.
snoosebaum
1 / 5 (1) Jul 31, 2018
howhot3
5 / 5 (1) Jul 31, 2018
Vostok; Russian as it comes don't you think? Let see if we can find it on the global temperature map;

https://earth.nul...8.89,582

Oh.. there it is surrounded by a large ring of very elevated temps. The deniers problem is it only gets worst from this time forward for hundreds of generations. As @gkam notes very wisely, we really need to find a way out of this jam.
unrealone1
1 / 5 (1) Aug 04, 2018
Antartica has increased in temperature over the last 20 years by how much?
0.1 degrees
Google the Antartica "Vostok " temp chart for the last 50 years.

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