Okay, maybe it wasn’t the Garden of Eden, but it was a lush, warm tropical habitat in the long ago time with a really, really big snake — Titanoboa.
You have to love a peer-reviewed climate science article in Nature titled, “Giant boid snake from the Palaeocene neotropics reveals hotter past equatorial temperatures,” (subs. req’d, abtract below). Nature News explains the article’s relevance:
Using models based on the largest modern-day snakes and their estimate of the Titanoboa‘s size, the team calculated how hot the tropics must have been 58 to 60 million years ago, a period known as the Palaeocene. The mean annual temperature would need to be at least 30-34 degrees Celsius to support the snake’s metabolism, the researchers report in Nature. This range matches previous estimates from Palaeocene climate models that assume high atmospheric carbon dioxide concentrations.
The results support the idea that the temperature difference between the Palaeocene tropics and higher-latitude regions was as large as it is today, even though the higher latitudes were much warmer during that time. This counters the so-called ‘thermostat’ hypothesis, which predicts that tropical temperatures would stay fairly stable even as other parts of the world heated up.
This “thermostat hypothesis” is a pet theory of famed denier Dr. Richard Lindzen, but like many small, defenseless pets, it was no match for a big snake, especially one estimated to have a “body length of 13 m and a mass of 1,135 kg.” A general debunking of Lindzen’s popular disinformation tracts can be found on RealClimate here.
If the world lets the sweet talk of denial and delay from the Lindzens of the world persuade us for another decade or so, then, like the snake’s seduction of Eve, we will lose our Garden of Eden — the miraculously narrow temperature window and livable climate that gave us modern human civilization — for 1,000 years or more.
The paper also sheds some light on the catastrophic greenhouse gas release of the Palaeocene-Eocene thermal maximum (PETM):
If our Palaeocene estimates are correct, tropical temperatures at the slightly younger (55.8 Myr ago) Palaeocene–Eocene thermal maximum (PETM) could have reached 38–40 °C, resulting in widespread equatorial heat-death as recent models and other proxy data have predicted.
A 2006 Nature analysis of deep marine sediments beneath the Arctic found Artic temperatures during the PETM almost beyond imagination–above 23°C (74°F)–temperatures more than 18°F warmer than current climate models had predicted (see “A methane feedback from the past strikes again“). The three dozen authors of the 2006 paper concluded that existing climate models are missing crucial feedbacks that can significantly amplify polar warming — as opposed to the imaginary negative feedbacks deniers like Lindzen claim while will magically save humanity from catastrophic warming (see Study: Water-vapor feedback is “strong and positive,” so we face “warming of several degrees Celsius”).
I wouldn’t say the big snake study is definitive by itself, but it is one more reason not to listen to the rattle of denial. Here is the abstract:
The largest extant snakes live in the tropics of South America and southeast Asia where high temperatures facilitate the evolution of large body sizes among air-breathing animals whose body temperatures are dependant on ambient environmental temperatures (poikilothermy). Very little is known about ancient tropical terrestrial ecosystems, limiting our understanding of the evolution of giant snakes and their relationship to climate in the past. Here we describe a boid snake from the oldest known neotropical rainforest fauna from the Cerrej³n Formation (58–60 Myr ago) in northeastern Colombia. We estimate a body length of 13 m and a mass of 1,135 kg, making it the largest known snake. The maximum size of poikilothermic animals at a given temperature is limited by metabolic rate, and a snake of this size would require a minimum mean annual temperature of 30–34 °C to survive. This estimate is consistent with hypotheses of hot Palaeocene neotropics with high concentrations of atmospheric CO2 based on climate models. Comparison of palaeotemperature estimates from the equator to those from South American mid-latitudes indicates a relatively steep temperature gradient during the early Palaeogene greenhouse, similar to that of today. Depositional environments and faunal composition of the Cerrej³n Formation indicate an anaconda-like ecology for the giant snake, and an earliest Cenozoic origin of neotropical vertebrate faunas.