CO2 levels measured in interglacials
before the mid-Bruhnes event (MBE), a large climate shift taking place ~430,000 years ago, are lower than the CO2 in interglacials
after the MBE.
Unlike the relatively mild interglacials
driven by the tilt, wobble and orbit of the Earth, the PETM fundamentally transformed the planet.
Over the past two million years, cyclical variations in the amount of solar energy reaching the Earth have caused it to experience a series of long glacial periods separated by short, warmer intervals known as interglacials
Humans could hardly be to blame if mammoths were able -- as in previous interglacials
-- to hole up in some chilly redoubt that was too remote for habitation or hunting.
At 12,000 years and counting, the Holocene has lasted longer than most of the previous interglacials
, and humans have capitalized on this extended period of global warmth.
As far as the Polish Carpathians are concerned, different pieces of evidence recently summarized by Olszak (2011) indicate that valley incision and deepening typified both glacial-interglacial
transitions as well as interglacials
themselves; the rates of uplift throughout the entire Pleistocene remaining constant.
During the interglacials
, the basin fills up with lakes.
The pollen in SU2, being overwhelmingly derived from trees, refers to their interglacial
origin, but not any typical forest succession or pollen-zonal record of known interglacials
was observed (Fig.
It appears that even during interglacials
the climate can oscillate between warm and cold, and yet the warm intervals are short-lived.
Until now, temperatures during the warm periods between ice ages - known as interglacials
- were thought to be only slightly warmer.
Earth did indeed plunge into an ice age about every 100,000 years, punctuated by warm spells, or interglacials
, that lasted about 10,000 years.
More recent interglacials
were only 10 000 to 20 000 years long and we're already 10 000 years into the current one.