Miami

The past CO2 increase I referred to was followed by a global spike in temperatures.

 

That's the correct answer tochatihu. CO2 counts as a factor, as do dozens of other pieces of a very complex puzzle. Scientists don't really understand how the earth's core, oceans, land, atmosphere, sun, and solar system interact. Our "climate models" are guesses that don't take into account hugely important and complicated factors. The current Al Gore "sky is falling" climate theory basically says zero out ALL of the traditional major climate factors and assume that the only thing driving climate change is CO2. Hardly settled.

 

Well, we are in an interglacial period. Humans and plantlife have flourished compared to the normal cold glacial climate. Earth's temperatures have been going up steadily for 18,000 years, as have CO2 levels, as have sea levels. If humans weren't on earth the temperature would still be at near record levels and CO2 would be around 300ppm.

 

I thought we knew fairly well how much heat was flowing up from the core and mantle. Do you have information that it is changing?

Steadily? Where did you get that?

 

Temperature, CO2 and sea levels have not increased steadily for 18 thousand years. Not if steadily means linearly, or at unchanging rates.

Naturally I am glad that evpm judges my response to be correct. Unfortunately I cannot return the favor. There is a lot to learn about this topic and I am not convinced that most of that learning is behind you.

 

And it would have taken thousands of years to reach that level. It has even been higher. The important factor is the rate of change though. In the planet's past, such fast rates of change only have occurred with cataclysmic events.

We are taking carbon that was sequestered over millions of years, and putting it back into the atmosphere at a rate that might be faster than any past massive eruption or asteroid strike ever did.

 

This describes a major shortcoming of paleoproxies for just about anything. They don't do 'rapid rates of change' well. We don't know how fast CO2 can be released from 'trap' volcanic areas. How fast oceans can flip to anoxic conditions.

(Our most recent) 100 ppm of +CO2 in 60 years seems fast, but we cannot say it never happened before. If it did, it was during some major event. Most of those were bad.

Pliocene and Pleistocene deglaciations featured 100 ppm of +CO2 over thousands of years.

 

The major disruption to the carbon cycle that preceded the P-T extinction may have occurred over a very short geological time span.
https://www.pnas.org/content/pnas/111/9/3316.full.pdf
The research was looking carbonate content of sediments, and found a steep drop in the amount over 2100 to 18,800 years. Not a direst measurement of atmospheric CO2, but a lot of carbon went somewhere that wasn't into sediment over a short time.

 

Here is a commonly displayed chart of the sea level rise since the last Ice Age.:


This rise clearly is not steady. It was fast for ~8k years (~half inch per year), really fast for several meltwater pulses during that time (nearly 2 inches per year), then very little the past 6k years, almost none the past several millenia+. But the rise has increased recently, ~8 inches since 1900, and now rising at a rate of ~1 foot per century.

 

Temperature rise has not been steady either. In fact, we were generally cooling for quite a while, before the recent upward spike began. From an source linked in this forum long ago:

Global Average Temperatures Are Close to 11,000-Year Peak - Scientific American
"After the ice age, they found, global average temperatures rose until they reached a plateau between 7550 and 3550 BC. Then a long-term cooling trend set in, reaching its lowest temperature extreme between ad 1450 and 1850.

Since then, temperatures have been increasing at a dramatic clip: from the first decade of the twentieth century to now, global average temperatures rose from near their coldest point since the ice age to nearly their warmest, Marcott and his team report today in Science."

 

We have seen that same sea-level history graphic posted here before.

Rather than get bogged down with Marcott (caught a lot of flak back in the day), suggest PAGES very detailed work. Many proxies, many dedicated people:

PAGES - Past Global Changes - A global multiproxy database for temperature reconstructions of the Common Era

Very few people remain unaware of the extremely non-linear patterns of atmospheric CO2 over Pleistocene/Holocene.

 

They have all gone up since the end of the Glacial Maximum 18,000 years ago. How "steady" the increase looks depends on the scale you choose.

Sea level up 450 feet.





CO2 up 120ppm before humans started burning stuff, and another 100ppm after that.





Temperature up 12°C.

 

"how "steady" the increase looks depends on the scale you choose"

That statement is absolutely true. If you choose scales between 140 thousand and 1 million years, wherein 18 thousand is squeezed into a narrow slice, all sorts of gyrations will appear steady.

 

And if you pick the right scale you can manipulate the data to emphasize your agenda.

The earth is getting warmer! (NASA)

World of Change: Global Temperatures

 

I searched for exclamation point (!) on that linked NASA page and did not find it.

 

Any in search of alternatives to CO2 interactions with infrared should notice:

It presents a thesis that (for now) I'd prefer not to tamp down with observed data. Because, if you have an agenda, here is an amenable purchase-able thing.

Let there be no doubt that Springer publishes many scientific journals that perfectly well follow standards. I publish articles there. I review manuscripts for their journals. But books (not just Springer's) are different, and efforts made on journals' side ought not 'gloss' the book side, without appropriate consideration.

In all cases know that Springer has an agenda of profiting from publishing. It's not a bad thing. But it can become complicated...

 

The claimed "Current Level" on that chart is very stale. Today's level is literally "off the chart" at 409 ppm, averaged 411 last month:
Daily CO2

 

I can see NASA's headline now... Atmospheric CO2 is Dropping. (no exclamation point)

 

That is normal seasonal variation.
Why Does Atmospheric CO2 Peak in May? | The Keeling Curve

Note the zig-zagging grey line. That is the 'day-to-day' measurement.

 

I'm suspicious when I see... "The results of this review and examination reveal no role of CO2 in any change of the Earth’s climate." on the back cover.

I can't believe a climate scientist would say that CO2 has no role in climate change, or that CO2 is the primary driver of climate change.