Stable Isotopes in Paleoclimate Reanalysis

Paleoclimate and Amerindians: evidence from stable isotopes and atmospheric circulation.

Two Amerindian demographic shifts are attributed to climate change in the northwest plains of North America: at approximately 11,000 calendar years before present (yr BP), Amerindian culture apparently split into foothills-mountains vs. plains biomes; and from 8,000-5,000 yr BP, scarce archaeological sites on the open plains suggest emigration during xeric "Altithermal" conditions. We reconstru...

Nitrogen Isotopes in Paleoclimate Research

Stable isotopes in tree rings

Stable isotopes in tree rings could provide palaeoclimate reconstructions with perfect annual resolution and statistically defined confidence limits. Recent advances make the approach viable for non-specialist laboratories. The relevant literature is, however, spread across several disciplines, with common problems approached in different ways. Here we provide the first overview of isotope dend...

Stable Isotopes in Ecosystem Studies

The use of stable isotopes to solve biogeochemical problems in ecosystem analysis is increasing rapidly because stable isotope data can contribute both source-sink (tracer) and process information: The elements C, N, S, H, and all have more than one isotope, and isotopic compositions of natural materials can be measured with great precision with a mass spectrometer. Isotopic compositions change...

Stable isotopes in carotenoid biochemistry

The use of stable isotopes in studies of carotenoid biosynthesis is reviewed, beginning with early work with l8 which defined the origin of oxygen in a range of xanthophylls. A series of experiments from our own laboratory is then described, in which 2H and 13C have been used to investigate the stereochemistry of cyclization to form C40 and C50 and i-ring carotenoids. Novel procedures involving...