What caused the Paleocene and Eocene periods to be so warm?

[cph]

Paleocene and Eocene were very warm, due to only tropical-like Antarctica findings? 35-65 myr ago, Antarctica would still be at south pole. And one would have a long night of 4-5 months; so not entirely like our tropics. Has the literature assumed that the entire planet is very warm? Drake's passage was closed, and Panama isthmus was probably open. Nothing is known about paleo-oceanic currents. Was a warm current perhaps wrapped around Antarctica; hence only regional warming?

 

[Andre]

Read the guidelines.

 

[Xnn]

At it's warmest during those periods, Antarctica was not tropical like.
Instead, the polar regions were at most a temperate rainforest.

Deep ocean currents are known to have been much warmer than they are now.
The tropics were larger and the temperature gradient between the equator and poles smaller. Clearly not a case of regional warming.

Still, you are referring to a period of 20 million years.
There was lots of variation over that time; but yes a considerably warmer period.