Climate Change

[Brigadier]

There's no way of knowing whether or not the climate changed by a few °C in a matter of decades 100,000 yrs ago, never mind 10million years ago.
We only have accurate data for about 100 years.

We only have directly measured data for about 170 years.

We have pretty accurate data for many centuries and millennia before that.

 

[Lirefighter]

I don't know. It is probably for optics rather than any technical reason. Maybe just to put it somewhere in the middle of the range.

There were fewer humans, with fewer machines emitting 'poisonous' co2 in the previous 29yrs of their base, so why not use that?
It would make the temp difference look even more alarming!
I think you are on to something when you mentioned the optics.

 

[MNW67]

There were fewer humans, with fewer machines emitting 'poisonous' co2 in the previous 29yrs of their base, so why not use that?
It would make the temp difference look even more alarming!
I think you are on to something when you mentioned the optics.

I don't think anybody is saying CO2 is "poisonous". Do you understand the basic theory of how physicists think CO2 warms planets (including the earth). And if you do, why do you believe that the 50% increase in CO2 we have experienced in the last century has not warmed the earth.

 

[Lirefighter]

We only have directly measured data for about 170 years.

We have pretty accurate data for many centuries and millennia before that.

No. The data from 10,000yrs ago is only accurate to a couple of °C or so, if that.
Narrowing down the date is even more difficult. The 'estimated' temperature for 50,000yrs ago could span several thousand years which is where the myth of 'the climate has never changed this fast before' comes from.
It's all guess work.

 

[Lirefighter]

I don't think anybody is saying CO2 is "poisonous". Do you understand the basic theory of how physicists think CO2 warms planets (including the earth). And if you do, why do you believe that the 50% increase in CO2 we have experienced in the last century has not warmed the earth.

Of course I do. The basics that is but your claim of a 50% increase in co2 is, whilst completely true, very misleading.
The levels of co2 in our atmosphere are miniscule, which is why they are presented in the ppm format.
450ppm is a tiny, tiny percentage, just 0.045% of our atmosphere. Oxygen is about 21% and the rest is primarily made up of nitrogen 78%.
You mentioned how bad the planet Venus is temperature wise on your sandwich board earlier.
The concentrations of co2 on Venus is about 96% of its atmosphere.
A 0.025% change in composition of our atmosphere is nothing to be concerned about.
It's all happened before, yet here we are.

 

[Brigadier]

No. The data from 10,000yrs ago is only accurate to a couple of °C or so, if that.
Narrowing down the date is even more difficult. The 'estimated' temperature for 50,000yrs ago could span several thousand years which is where the myth of 'the climate has never changed this fast before' comes from.
It's all guess work.

Yes.

It might be even worse than is currently reported.

 

[MNW67]

Of course I do. The basics that is but your claim of a 50% increase in co2 is, whilst completely true, very misleading.
The levels of co2 in our atmosphere are miniscule, which is why they are presented in the ppm format.
450ppm is a tiny, tiny percentage, just 0.045% of our atmosphere. Oxygen is about 21% and the rest is primarily made up of nitrogen 78%.
You mentioned how bad the planet Venus is temperature wise on your sandwich board earlier.
The concentrations of co2 on Venus is about 96% of its atmosphere.
A 0.025% change in composition of our atmosphere is nothing to be concerned about.
It's all happened before, yet here we are.

There are satellites in space which measure all this. They can see the amount of heat being trapped by the CO2 in the atmosphere. A small amount of CO2 can make a big difference.

 

[Munroast]

There's no way of knowing whether or not the climate changed by a few °C in a matter of decades 100,000 yrs ago, never mind 10million years ago.
We only have accurate data for about 100 years.

I think you are probably underestimating the accuracy of oxygen isotope ratios from ice core samples 800,000 years old, probably better than 1°c

Sometimes we just have to accept as fact things we would rather were not true. I wish you were right, but virtually all the scientists in the world are pointing in the other direction.

 

[Notch7]

You are just parroting what you've been told

Please could you say what your sources are for climate change.

 

[Notch7]

The levels of co2 in our atmosphere are miniscule, which is why they are presented in the ppm format.
450ppm is a tiny, tiny percentage, just 0.045% of our atmosphere. Oxygen is about 21% and the rest is primarily made up of nitrogen 78%.

iron makes up only about 0.006% of the mass of an average human but it’s completely essential to how we live.

CO2 has 2 key properties: It diffuses very evenly throughout the atmosphere and it is extremely effective at absorbing and re-radiating heat.

 

[Lirefighter]

There are satellites in space which measure all this. They can see the amount of heat being trapped by the CO2 in the atmosphere.

Why did you edit your post?
I had a look for the info regarding the satellite data, but couldn't find anything that backs up your claim. I've only scanned over the articles though.
Do you have a link?

 

[MNW67]

Why did you edit your post?
I had a look for the info regarding the satellite data, but couldn't find anything that backs up your claim. I've only scanned over the articles though.
Do you have a link?

I changed it because I realised I had got one bit wrong. I haven't looked at this properly for a long time. Here is what I have found so far. It's just the AI overview at the moment.

Do you know anything about absorption and emission spectra? Most people probably won't. Basically, physicists know what wavelength of infra red is absorbed by CO2 and the satellite can therefore measure how much is making it through to space and how much is being trapped in the atmosphere by CO2.

Google Search

Yes, satellites can measure the amount of heat trapped by CO2, and other greenhouse gases. They do this by detecting the infrared radiation that Earth emits and measuring how much is absorbed by the atmosphere. Specifically, satellites can measure the spectrum of outgoing infrared radiation, allowing scientists to identify and quantify the amount of radiation trapped by CO2 and other gases.

Here's a more detailed explanation:

• Infrared Radiation:
  Earth's surface emits infrared radiation (heat) into space. Greenhouse gases, like CO2, absorb some of this infrared radiation.
  
  
• Satellite Measurement:
  Satellites equipped with radiometers and spectrometers can detect and measure the amount of infrared radiation escaping Earth's atmosphere.
  
  
• Absorption Bands:
  Different gases have specific absorption bands in the infrared spectrum, meaning they absorb infrared radiation at certain wavelengths. CO2 has a strong absorption band centered at a wavelength of 15 micrometers.
  
  
• Measuring Heat Trapping:
  By comparing the amount of infrared radiation that Earth emits with the amount that escapes into space, scientists can determine how much heat is being trapped by the atmosphere, particularly by greenhouse gases like CO2.

 

[Lirefighter]

I think you are probably underestimating the accuracy of oxygen isotope ratios from ice core samples 800,000 years old, probably better than 1°c

Sometimes we just have to accept as fact things we would rather were not true. I wish you were right, but virtually all the scientists in the world are pointing in the other direction.

Apart from all the scientists who have a vested interest in the fossil fuel industry.
Which is coincidentally all of the ones who go against the grain, so I'm told.
Most of them get the sack too, which is nice.

 

[Notch7]

A 0.025% change in composition of our atmosphere is nothing to be concerned about

Why do you believe that?

 

[Koolpc]

I believe that the true cause of climate change is cats. Really, i do! They started it all. Its a fact.