WATER VAPOR CYCLING. Water vapor is present in the atmosphere in only trace amounts. Yet, the presence and cycling of this vapor has an inordinate influence on climate, both locally and globally, and is critical for supporting life. Using the stable isotopes of water, we investigate both modern cycling of water vapor and its exchanges with the land surface, and past changes in water cycling and what it might tell us about ancient environmental conditions. We do this in two ways:
- Water isotope sampling. We have conducted sampling campaigns in both Bolivia and Wyoming to investigate water vapor cycling in mountainous regions. In Wyoming, we are deploying a cavity ring down spectrometer to document isotope variability on diurnal to seasonal time scales, and to quantify the contribution from surface fluxes.
- Water isotope modeling. We use isotope-enabled climate models, and compare them with modern observations and proxy data, to investigate variability in water cycling in modern and past climates. We are particularly interested in exploring what terrestrial proxy records of water stable isotopes tell us about past conditions and whether they can be used to reveal past surface elevations.
- Insel, N., Poulsen, C.J., Ehlers, T.A., and Sturm C. (2012). Response of meteoric d18O to surface uplift - Implications for Cenozoic Andean Plateau growth. Earth and Planetary Science Letters, 317-318, p 262-272. doi:10.1016/j.epsl.2011.11.039.
- Poulsen, C.J. and Jeffery, M.L.., (2011). Climate change imprinting on stable isotopic compositions of high-elevation meteoric water cloaks past surface elevations of major orogens, Geology, 39, 595-598, doi:10.1130/G32052.1.