/sci/ - Science & Math

[Anonymous No.15993391]

How come it was so much warmer 3000 years ago when atmospheric CO2 levels were far lower than they are currently?

[Anonymous No.15993415]

Milankovitch cycles

[Anonymous No.15993543]

How can you tell when there's not even a y axis?

[Anonymous No.15993600]

>>15993391
>>15993543
That's the climate of Europe, not the global climate. You should know the difference.

[Anonymous No.15993679]

>>15993600
OP's image clearly says "global"

[Anonymous No.15993715]

>>15993679
And? That graph has clearly been cropped and it's trivial to change a label. The fact is that data matches the climate of Europe and not the global climate. Whoever made or altered it did so with the intention of tricking you and it worked.

[Anonymous No.15993718]

>>15993391
that graph is bullshit.

[Anonymous No.15993741]

>>15993715
Are you seriously arguing with the anon who posted >>15993543?

[Anonymous No.15993751]

>>15993741
He's probably just gullible. Maybe if he understands that people who are trying to convince him that science is a hoax are lying to him to further their own agenda then he won't be as susceptible to it.

[Anonymous No.15993842]

>>15993391
>Fahrenheit
this is a science board anon

[Anonymous No.15994652]

>>15993715
james hansen, the author of that image, is a known liar and a fraud. he has been making his living forecasting doomsday for the past 4+ decades and he has always been wrong. he is now over 80 years old and still has never accomplished anything worthwhile in his entire career in the sciences.

[Anonymous No.15995138]

>>15994652
Nonsense.

[Anonymous No.15995340]

>>15995138
Amazing we had temperature bouys in the middle of the pacific during the Roman and Medieval eras that proved warming was only local, otherwise we might have thought that all written sources describing a global warm period were accurate!

[Anonymous No.15995424]

>>15995340
Such as?

[Anonymous No.15995511]

>>15993718
no it isn't

[Anonymous No.15995584]

>>15995424
Such as the fact that Romans grew French wine grapes in Britain. Such as Chinese almanacs. Such as pretty much every written source at the time. The Roman and Medieval Warm periods were not "discovered" by later scientists, they were known and attested to for centuries.

[Anonymous No.15995591]

>>15995584
>Such as the fact that Romans grew French wine grapes in Britain.
That doesn't prove it was a global event. See >>15993600


>Such as Chinese almanacs.
China is in the northern hemisphere.

>Such as pretty much every written source at the time.
Which ones say it was a global event? Which ones even come from the southern hemisphere?

>The Roman and Medieval Warm periods were not "discovered" by later scientists, they were known and attested to for centuries.
By people where this local event happened. It was not a global event.

[Anonymous No.15995683]

>>15995340
So hi, I'm an actual Earth scientist. We use proxy data for anything prior to the 1850s. You should know that. OPs image is of proxy data. You can't use proxy data and then say you won't believe proxy data. That's legit retarded.

So, some examples of proxy data.
Did you know that sand and dust get trapped on top of ice sheets? So if you've got an ice sheet over water none of that sand and dust can reach the ocean floor. Anything that DOES reach the ocean floor beneath ice is very, very fine grains of dust that can travel for long distances suspended in water. If you therefor take core samples of the arctic seafloor you can actually measure changes in ice cover over time.

Proxy data!

Did you know that certain foraminifera change the rotation of their shells according to temperature? It's true! Then have a clockwise spin on their shell at one temperature and a counterclockwise spin at another temperature. So if you find those little suckers buried and fossilized 100,000,000 years ago you can take a percentage of the shells spun clockwise and a percentage of the shells spun counterclockwise and actually tell what the temperature was.

Proxy data!

Did you know until the 20th century trees would grow with wider tree rings when it was warm and thinner tree rings when it was cool. In the 20th century this no longer works because pollution is now also a factor. But any trees from before the 20th century you can look at the thickness of tree rings over time, compare them to other trees from the same area and get an average temperature.

Proxy data!

[Anonymous No.15995685]

>>15995683
Redditor

[Anonymous No.15995687]

>>15995683
Bonus fact, in the email from "Climategate" this is what the two scientists were talking about. Tree ring data was showing a false decline in the 20th century because of pollution, but if you use a certain trick (a technique) to work out what the tree ring size would have been without pollution you can STILL use tree ring data to work out average temperatures in areas where you don't have thermometers. This is what they meant when they said they used a nature trick to hide the decline but because you bozos never tried learning what the email was about you still think it was some nefarious plot. You retards

Did you know that it takes more energy to evaporate water if the oxygen in it has 2 extra neutrons? The Oxygen-18 atom is a stable isotope of oxygen and about .2% of all oxygen on the Earth is oxygen -18. Because it takes more energy to evaporate water with 2 extra neutrons when you trap ice in glaciers you can measure the percentage of oxygen-18 in the ice to tell exactly how hot the oceans were at the time the ice formed.

Proxy data!

It is very possible to tell with good accuracy what the earth's temperature has been over time. These are a few and I'm running out of room on these posts.
https://www.ncei.noaa.gov/news/what-are-proxy-data

[Anonymous No.15995689]

>>15995685
Don't worry, I'm only talking down to you because you act like a child.

[Anonymous No.15996055]

>>15995687
thats not what was going on in the climategate emails

[Anonymous No.15996404]

>>15996055
Why don't you explain in detail what you think happened in the climategate emails. I'm sure this will be good for a laugh.

[Anonymous No.15996892]

>>15996055