Historical Climatology
Abstract
The research program in Historical Climatology has the general purpose to show feasibility of determining global climate in the past, by determining past trends in surface temperature of the earth. The method being studied involves measuring past temperatures using isotope 'thermometers' in bio-organic bases. For example, isotope ratios in tree rings being formed are expected to change if the temperature changes; thus tree rings formed long ago may exhibit different ratios than those being formed today. Lower limits on the temperature coefficients have been computed, and compared favorably with experimental coefficients. New measurements of these coefficients have been undertaken in water plants. Feasibility of measurement of the isotope ratio by neutron activation for oxygen has been demonstrated and feasibility of measurement of D/H, C13/C12 and O18/O16 has been demonstrated by elastic backscatter of low energy protons. The variations of isotope ratios in two trees have been measured and the correlation with historic weather records is being studied. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 01, 1972
- Accession Number
- AD0757225
Entities
People
- Leona M. Libby