According to Danish politician Karl Kristian Steincke, “It is difficult to make predictions, especially about the future.” Steincke was cataloging a comment made in the 1937–38 session of the Danish Parliament (without translation: “Det er vanskeligt at spaa, især naar det gælder Fremtiden”), which if you consider what befell Denmark shortly thereafter, was prescient.
[R]ecord CO2 levels are accompanied by record temperatures and record sea level rise. We haven’t hit the temperature levels we can expect from current CO2 levels, and by the time we do, CO2 levels will be even higher. Sea level rise can take even longer to catch up but the latest science says we are headed towards worst-case scenario levels, 3 to 6 feet (or more), by century’s end.But now CO2 levels have surpassed those seen not just during modern civilization, but during all of human evolution. Indeed, current levels haven’t been seen for many millions of years.
Monthly levels of heat-trapping CO2 hit nearly 410 parts per million (ppm) in May. How do we explain that? Only one way. What were once natural sinks have become sources, as CO2 reservoirs trapped in permafrost, ocean clathrates, forests and soils heat up and start to release their stores.
Many factors — the depth of the gas hydrates in sediments, strong sediment and water column sinks, and the inability of bubbles emitted at the seafloor to deliver methane to the sea-air interface in most cases — mitigate the impact of gas hydrate dissociation on atmospheric greenhouse gas concentrations though. There is no conclusive proof that hydrate-derived methane is reaching the atmosphere now….
The most revealing of Romm’s charts was, for us, this one from Yale360, to which we have added a few labels for clarity:
The people of Jebel Irhoud were certainly sophisticated. They could make fires and craft complex weapons, such as wooden handled spears, needed to kill gazelle and other animals that grazed the savanna that covered the Sahara 300,000 years ago.
“We used to think that there was a cradle of mankind 200,000 years ago in East Africa, but our new data reveal that Homo sapiens spread across the entire African continent around 300,000 years ago. Long before the out-of-Africa dispersal of Homo sapiens, there was dispersal within Africa,” study author Jean-Jacques Hublin said in a statement.
“CO2 levels have surpassed those seen not just during modern civilization, but during all of human evolution. Indeed, current levels haven’t been seen for many millions of years.”
Even if sea levels rise 300 feet and cover coastal cities, those minerals will still be visible in the sedimentary record. That’s because landmarks like the Washington Monument and the Smithsonian will collapse into piles of rubble — signatures that are later preserved as highly unusual lens-shaped pockets underground, distinct from their surroundings in both shape and minerals. The Washington Monument, for example, will eventually be a lens-shaped pocket composed of limestone where no other limestone is found. And the pocket that was once the Smithsonian will contain so many rare minerals that they could not possibly have formed so close together in nature. To boot, they will be surrounded by the vast array of the man-made minerals we use every day.
There is nothing at all like this in the geology of the past 4.5 billion years on Earth,” Zalasiewicz says. “It is tragically different.”
Wherever you roam
And admit that the waters
Around you have grown
And accept it that soon
You’ll be drenched to the bone
If your time to you
Is worth savin’
Then you better start swimmin’
Or you’ll sink like a stone
For the times they are a-changin’.