Humidity estimate for the middle Eocene Arctic rain forest
نویسندگان
چکیده
Note: MAT—mean annual temperature; CMM—cold month mean temperature; NLR—nearest living relative analogy; CLAMP—climate–leaf analysis multivariate program. ABSTRACT The exquisite preservation of fossilized Metasequoia trees that grew near 808N latitude during the middle Eocene (ca. 45 Ma) in Nunavut, Canada, allowed for dD and d18O analyses of cellulose, techniques previously restricted to wood ,30,000 yr old. From the isotopic results, we determined that the middle Eocene Arctic atmosphere contained ;23 the water found in the region’s atmosphere today. This water vapor contributed to a middle Eocene greenhouse effect that insulated the polar region during dark polar winters.
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