Global temperature change attributable to external factors, confirms new study

global warming
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Researchers at the University of Oxford have confirmed that human activity and other external factors are responsible for the rise in global temperature. While this has been the consensus of the scientific community for a long time, uncertainty remained around how natural ocean-cycles might be influencing global warming over the course of multiple decades. The answer we can now give is: very little to none.

In a new study, published in the Journal of Climate, researchers at the Environmental Change Institute looked at observed ocean and land temperature data since 1850. Apart from human-induced factors such as greenhouse gas concentrations, other occurrences such as , solar activity and air pollution peaks were included in the analysis. The findings demonstrated that slow-acting ocean cycles do not explain the long-term changes in , which includes several decades of accelerated or slowed warming.

'We can now say with confidence that human factors like greenhouse gas emissions and particulate pollution, along with year-to-year changes brought on by natural phenomenon like volcanic eruptions or the El Niño, are sufficient to explain virtually all of the long-term changes in temperature,' says study lead author Dr. Karsten Haustein. 'The idea that oceans could have been driving the climate in a colder or warmer direction for multiple decades in the past, and therefore will do so in the future, is unlikely to be correct.'

The study showed that global warming that occurred during the 'early warming' period (1915—1945) was in fact caused by external factors as well. Formerly, it had been largely attributed to natural ocean temperature changes, which is why there has been uncertainty over how much of is influenced by unpredictable natural factors.

'Our study showed that there are no hidden drivers of global mean temperature,' says co-author Dr. Friederike Otto. 'The temperature change we observe is due to the drivers we know. This sounds boring, but sometimes boring results are really important. In this case, it means we will not see any surprises when these drivers—such as gas emissions—change. In good news, this means when go down, temperatures will do so as predicted; the bad news is there is nothing that saves us from temperatures going up as forecasted if we fail to drastically cut .'


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Role of 'natural factors' on recent climate change underestimated, research shows

More information: Karsten Haustein et al, A limited role for unforced internal variability in 20th century warming., Journal of Climate (2019). DOI: 10.1175/JCLI-D-18-0555.1
Journal information: Journal of Climate

Citation: Global temperature change attributable to external factors, confirms new study (2019, May 22) retrieved 16 June 2019 from https://phys.org/news/2019-05-global-temperature-attributable-external-factors.html
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May 22, 2019
It is also clear from the data, that the low carbon dioxide levels of the last few million years has led to wild temperature swings and ice ages. Getting back to 400 to 500 ppm will be good for the earth ecosystem. Please see the following image for temperature and carbon dioxide levels the last 3 million years. https://www.googl...U_R9kBM:

May 22, 2019
Among other things, actually, the article does not state that manmade effects in the air are to blame for changes in climate. It only says that oceanic causes cannot be used to explain most of the changes in climate, but it also allows things like volcanic eruptions, "el Nino" and such to be blamed.
In fact, though, it is chemtrails causing the changes in the behavior of the atmosphere. They began invisible in the early Fifties, but already caused the number of tornadoes to skyrocket from a nearly constant 180 to nine or more times that number now. In 1997, chemtrails became visible, apparently because the air became saturated with chemical. The major changes attributed to "climate change' have happened since 1997.

May 22, 2019
it is chemtrails causing the changes


Insane baloney. We've seen contrails (condensation trails) in jets since they existed. Basic physics of a hot turbine in wet air. Your chem trails are true delusion. Take your meds.

May 22, 2019
Julianpenrod,
The vapor trails from WWII heavy bombers were very visible. Just sayin'.

May 22, 2019
It is tragic that the same old actors can still publish model results under Oxford's name (and Physics') as if they were Data. They cannot be, anymore than I can sing Soprano.
Obviously no real Scientists involved here.... Brett

May 22, 2019
Boring, but predictable. Now there are no more excuses left.

Julianpenrod, The vapor trails


So instead of excuses we get lunatic conspiracy theories? Oy!

It is tragic that the same old actors can still publish model results under Oxford's name (and Physics') as if they were Data.


Or we get people trolling science as if that would help them - amusing.

Blocked for inane trolling.

May 22, 2019
grandpa
Please see the following image...
And if you follow the image back to it's source - you get this - http://www.realcl...-change/
Read the frigging article grandpa...
our results indicate that the current CO2 concentration of ~410 ppm is unprecedented
failure to significantly reduce CO2 emissions to comply with the Paris Agreement target of limiting global warming well below 2°C will not only bring Earth's climate away from Holocene-like conditions, but also push it beyond climatic conditions experienced during the entire current geological period

May 22, 2019
It's beyond amusing to witness, what jackasses, the AGW Cult takes their Chicken Littles for. Feeding them loads of bullshit, which they hungrily gobble up.

May 22, 2019
All models, no Data worth mentioning. Please display actual data for our discussion..... Brett

May 22, 2019
Among other things, actually, the article does not state that manmade effects in the air are to blame for changes in climate. It only says that oceanic causes cannot be used to explain most of the changes in climate, but it also allows things like volcanic eruptions, "el Nino" and such to be blamed.
In fact, though, it is chemtrails causing the changes in the behavior of the atmosphere. They began invisible in the early Fifties, but already caused the number of tornadoes to skyrocket from a nearly constant 180 to nine or more times that number now. In 1997, chemtrails became visible, apparently because the air became saturated with chemical. The major changes attributed to "climate change' have happened since 1997.
say julian penned

I see the chemtrails occasionally coming out as exhaust from military planes. It's possible that the fault lies in the chemical mixture that is used as jet fuel. I believe there are certain additives that are used in their fuel.

May 22, 2019
FROM ANOTHER PHORUM:

"Surveillance_Egg_Unit
6 hours ago
"Over periods of about 50,000 years, Mars leans toward the sun before gradually returning to an upright position, like a wobbling spinning top. When the planet spins upright, the equator faces the sun, allowing the polar ice caps to grow. As the planet tilts, the ice caps retreat, perhaps vanishing entirely."

I would like to know if the Earth is TILTING TOWARD THE SUN NOW where the Sun's warmth/radiation would cause the ice to melt in northern latitudes, such as tundra melting. Does anyone here know?
If it happens on Mars, why then couldn't it also happen on Earth if the Earth has a slight wobble. And the Earth is much closer to the Sun.

May 22, 2019
apparently they have never heard of the sun in Oxford

May 22, 2019
SEU: We always have a tilt barring twice a year at equinoxes. Changes in tilt, ellipse size, and dates of solstices relative to seasons, that is the Milankovich Cycles, are thought to be large factors in Ice Ages. Longer occurrences eg Permian, may come from our Galactic orbit through dust clouds. 60+ yr cycles are possibly related to Solar System Orbital/Gravity Dynamics. Work proceeds on that including at NASA.
The Northern Polar Ice cycle lags the Pacific Ocean temperature one by 10 plus yrs, and tends to also run warm/cold over repeating c.31-2 yearly cycles.
Last warm NP one began early nineties, and now a Cold one has begun. Both warm and cold cycles take some years to show but certain events of the last 2-3 yrs indicate it is happening. Time as usual will tell.... Brett

May 23, 2019
@S_E_U.
FROM ANOTHER PHORUM:

"Surveillance_Egg_Unit
6 hours ago
"Over periods of about 50,000 years, Mars leans toward the sun before gradually returning to an upright position, like a wobbling spinning top. When the planet spins upright, the equator faces the sun, allowing the polar ice caps to grow. As the planet tilts, the ice caps retreat, perhaps vanishing entirely."

I would like to know if the Earth is TILTING TOWARD THE SUN NOW where the Sun's warmth/radiation would cause the ice to melt in northern latitudes, such as tundra melting. Does anyone here know?
If it happens on Mars, why then couldn't it also happen on Earth if the Earth has a slight wobble. And the Earth is much closer to the Sun.
The combination of tilt/yearly orbit results in 'seasons' around the year (Mars' 'year' is nearly twice that of Earth's)...ie, BOTH polar regions get insolation during their respective 'summer' season.

In short: tilt CANNOT be THE cause of INCREASED warming GLOBALLY. :)

May 26, 2019
More complete crap from the alarmist fools.

May 26, 2019
More complete crap from the alarmist fools.


More scientifically illiterate opinion from unqualified laymen.

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