Mid-Cretaceous Period
ca. 120 to 90 Million Years Ago
The Mid-Cretaceous period is one period in the geologic past that stands out as distinctly warmer than today, particularly at high latitudes. During the mid-Cretaceous Period, 120-90 million years ago, fossil remains of plants and animals believed to inhabit warm environments, were found at much higher latitudes. Breadfruit trees apparently grew as far north as Greenland (55° N), and in the oceans, warm water corals grew farther away from the equator in both hemispheres. Cretaceous period occurred far enough in the past that continents were in different positions, with different mountain chains and shallow seas in some places that do not exist today.
The mid-Cretaceous was characterized by geography and an ocean circulation that was vastly different from today; as well as higher carbon dioxide levels (at least 2 to 4 times higher than today). This indicates that the mid-Cretaceous climate system was different from that of today or any we might have in the future. Explanations evoking ocean and atmospheric circulation patterns radically different from today have been proposed to explain the climate of the mid-Cretaceous; however, there is no scientific consensus on how the Mid-Cretaceous warm climate came about.
For larger viewing of image, please click here or on image. Map credits: Data from many sources. Image re-created from text, "Distribution of Climatically Sensitive Deposits for the mid-Cretaceous (Aptian-Albian-Cenomanian, 120-90 Ma.)", for full scientific reference of text click here.
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