## Thursday, October 03, 2019

### The Cretaceous vs the Gretaceous

A British left-wing rag, The Independent, has finally admitted that Greta Thunberg is a pathological liar.

They have published evidence (including her own confession) that Greta Thunberg had a dream – and one about the powerful. But in the U.N. speech just days away from that article, she claimed that the powerful have stolen her dreams. Clearly, according to The Independent, the powerful gave her the dreams because they appear in those dreams – instead of stealing them.

People shouldn't be lying in front of the microphone in the United Nations in this self-evident and provable way. I eagerly await the admission by The Independent that everything else that she is saying are lies, too.

Steven S. has pointed out that a new geological epoch has started, the Gretinocene. Let me assume that the correct name is the Gretaceous because it sounds very similar to the Cretaceous [not only for Czechs: krýtejš@s]. The hyperlink in this paragraph is the most important one for you to click at – and study the page!

For us not to forget some geology, it's helpful to compare the Cretaceous and the Gretaceous.

What the epoch is famous for

The Cretaceous is famous for its chalk (which gave the name to that epoch, DE: Kreide, CZ: křída), the Gretaceous is famous for its fanatical talk. The chalk is no longer needed in the Gretaceous because Greta is skipping the classes. Instead, she is collecting the Tesla cars from the likes of Arnold Schwarzenegger and sailing completely but completely carbon-free yachts that are made out entirely of carbon fiber ;-) and nothing else.

Beginnings

The Cretaceous – the last subepoch of the Mesozoic Era (CZ: of the second-mountains) – started 145 million years ago when the Jurassic Period ended. The Gretaceous started in 1993 when Jurassic Park, a film by the late TRF reader and climate skeptic Michael Crichton, was released to the movie theaters. The actual Greta wasn't born for another decade but the new period was already ongoing.

The first and last subepoch

The last subepoch of the (late) Cretaceous is the Maastrichtian. On the contrary, the Maastrichtian is the earliest epoch of the Gretaceous because the Maastricht Treaty became effective in 1993 (the year of the Jurassic Park) and the seismic shifts started to shape Europe and the world (the European Union in its deeply problematic current form and under this modern name was born in 1993). That treaty was a precursor to the rise of the actual Greta and is used as the defining moment of the Gretaceous.

Oxygen content

In the Cretaceous, the mean concentration of oxygen O2 in the atmosphere was 30% which is 1.5 times the Gretaceous concentration, around 20%. These days, we are being choked and our freedom to breathe etc. is being eroded – but no one seems to care about that.

CO2 concentration

The Cretaceous had the average concentration of CO2 around 1700 ppm (parts per million). The concentration we see nowadays, is around 400 ppm. Despite the claims that the rise of CO2 above 400 ppm is dangerous, the Cretaceous had no problems with concentrations that were more than 4 times higher than today – for some reasons.

The temperature

The mean surface temperature is believed to be around 18 °C in the Cretaceous; it's around 15 °C today and it was around 14 °C in the pre-industrial era. It is foolish to pretend that we may greatly improve the precision of these numbers right now.

Finally, this blog post is going to say something else than lame jokes and childish analogies! ;-) Creta's world was almost certainly several degrees warmer than Greta's world. It is not known whether this difference may be attributed to the CO2.

But if it may be attributed largely to CO2, a totally consistent picture emerges. The Cretaceous vs the Gretaceous (now) had concentrations 1700 and 410 ppm – they differ by a factor of four or two doublings on the logarithmic scale. The temperature of the Cretaceous was 3 °C higher than now. Divide these two numbers and you will see that one CO2 doubling may be associated approximately with 1.5 °C of warming which roughly agrees with the 1.2 °C, the feedback-free climate sensitivity per doubling of CO2.

If you're a beginner, let me say that it makes sense to compute the sensitivity "per doubling of CO2" because the rise of the temperature due to the greenhouse effect is approximately a logarithmic function of the concentration.

The end of the epoch

The Cretaceous ended with the extinction event 66 million years ago – an asteroid collided with Mexico. The Gretaceous hasn't ended yet but we're promised that it will end by the meltdown or evaporation of the life on Earth or the Earth itself. Clearly, we need to warm the planet by a lot more because the much warmer Cretaceous was doing just fine and it was something completely different than the warm climate that killed almost all the dinosaurs.

In particular, I want you to understand the implications of geology. There is clearly nothing dangerous about the CO2 concentration in the atmosphere that is 1700 ppm or so, 4 times higher than today. The Earth was thriving, as the picture at the top indicates. This is what the actual science about these matters says. No one who is scientifically literate may ever say sentences such as "1700 ppm of CO2 in the atmosphere is dangerous for life on Earth" because this statement is self-evidently preposterous from the scientific viewpoint, even from the viewpoint of natural science that the eighth-graders should already know.

Mankind has almost no chance to increase the CO2 concentration from 410 ppm to 1700 ppm in the next 200 years – because Nature's mechanisms returning the number back to 280 ppm will get stronger if or when the concentration gets much higher. So if you want us to panic about the CO2 concentration that causes dangerous climate change, can't you allow us to delay the panic at least by these 200 years? Thank you very much for your generosity!

Life in the Cretaceous

Again, the Cretaceous lasted between 145 and 66 million years ago. It's a long time ago and there were no humans on Earth yet. But life of the Cretaceous makes it very clear that life was otherwise very close to what we see today.

In particular, the trees similar to the present trees had existed for a long time before the Cretaceous, of course. But in the Cretaceous, Earth has also seen the explosion of the beautiful, flowering plants that we know today (angiosperms, CZ: the coveredseeded plants) as well as those aforementioned older gymnosperms (CZ: nakedseeded plants) and other conifers (CZ: needlesy plants, the Czech taxonomy is vastly more informative, isn't it?). Add figs, planes, magnolias, anything you like.

When it comes to animals, there were no humans but there were lots of dinosaurs. It's up to you to decide which of these is more important for making the fauna more diverse and interesting.

Otherwise there were all the basic classes of animals that you know – insects including bees and butterflies; but also the bigger and more modern animals all the way up to the birds and mammals (usually smaller mammals); dinosaurs in the seas along with the sharks and waterbirds and marine birds etc.

Humans – who didn't exist in the Cretaceous yet – are special in some respects. But in others, the human species is just another animal species! In particular we don't differ much by our regulation of the temperature and sensitivity towards the temperature etc. from many animal species (such as the small mammals) that already did exist in the Cretaceous. Why? It's because, in other words, the thermal regulation mechanisms used by humans is an old biotechnology – much older than the human race. (But not too old: only birds, mammals, and perhaps a few dinosaurs have been warm-blooded.) Also, our gadgets including smartphones typically withstand wider temperature ranges than ourselves.

That's the reason why, from the biological viewpoint, the existence or non-existence of humans in an old epoch is irrelevant for the question whether that old epoch may be visualized as a "climatic role model" for the present. The Cretaceous is a totally fine role model for the present because there were tons of plants and animals whose relationship and interactions with the CO2 and temperature were almost indistinguishable from the relationships that the currently existing species – including humans – have.

Nothing important would break down about the life on Earth if the CO2 concentration rose to 1700 ppm and the global mean temperature grew by 3 °C to 18 °C. The Cretaceous – between 145 and 66 million years ago – was a biologically thriving world. (I plan to write a more detailed blog post explaining why the uniform warming of the Earth by 100 °C in a few years would basically guarantee the survival of millions of humans.)

The average TRF reader is 84 years old but sometimes a downward fluke occurs. So for all the kids who accidentally opened this page and who are planning to skip the classes tomorrow again – because it's another Friday – don't go to the streets this time. Sit down at home, open the Internet, and study "creta" (Latin: the chalk) so that you know at least as much about "creta" and the Cretaceous as you know about Greta! Try to think what this seemingly boring and detached knowledge may teach you about the hot topics of the present.

If you partly cure your scientific illiteracy concerning "creta" (or anything else that is equivalent), your views on Greta will significantly change, too.

Bonus: Already in 2011, the BBC host Jeremy Clarkson – who recently pointed out that Greta was a spoiled brat without gratitude to the older generations that have created everything for her – invented a carbon-neutral future behind the Range Rover: a greenhouse fed by the exhausts and filled with gas similar to the highly hospitable atmosphere of the Cretaceous. Clarkson's technology had some serious bugs – much like all other existing methods to reduce the CO2 emissions.