Phanerozoic 550 Ma

Cenozoic 65 Ma

Late Cretaceous Southern Ocean Not shown – plateaus in the southern Indian Ocean

Zachos Cenozoic record

Linear, non-linear, and threshold responses Fractal strange attractors

Eocene Thermal Maximum

Eocene circulation Low-latitude east to west circulation, similar to Cretaceous

Southern Ocean gateways STF = Subtropical Front AAPF = Antarctic Polar Front AAD = Antarctic Divergence SAF = Subantarctic Front

Late Cenozoic sea level

Oligocene ice growth One of the largest, most rapid drops in sea level during the Phanerozoic Truly cold deep water Bottom temp’s may have dropped 4-5°C

Topography of Antarctica without ice

Crossing a threshold – Rapid growth of the Antarctic Ice Sheet

Iceland-Faeroe Ridge Initial connection with the Arctic Ocean in the Paleocene Spill-over in late Eocene cools deep water in Atlantic Finally open to deep water in late Miocene

NADW site map

Australia separates from Antarctica Contributed to late Eocene cooling of the deep ocean Major cause of thermal isolation of Antarctica in Oligocene

Oligocene circulation The only remaining barrier is the Drake Passage Progressive blockage of the Indonesian Seaway

Miocene Southern Ocean Deep-water flow between Australia-New Zealand and Antarctica Surface-water flow through Drake Passage initiated in Oligocene Now deep flow begins

Late Miocene – the Messinian salinity crisis

High topography Western North America

Orographic effect

India collides

Tibetan Plateau

Northern Indian Ocean 90 East Ridge Chagos- Laccadive Plateau

Himalayas and monsoons

Monsoons

Monsoons and Indian Ocean circulation

Looking into the Himalayas

Sediment flux to ocean basins – 40 Ma

Strontium isotopes 400 Ma

Pliocene 5.5 Ma

Closure of Panama – Pliocene

Table SL fall 80 Ma

Raymo 5 Ma record

Raymo 41-ky to 100-ky cycles

Mid to Late Pleistocene 450 ka

Holocene temperature variations

Late Holocene 1000 years

Instrumental records 150 years

cooling

warming

…to be continued