text: Clumped isotope analyses have recently been used to constrain the paleoaltitude or uplift history of a region.  Air temperature decreases systematically with altitude throughout the troposphere (see lapse rate).  Due to the close coupling between lake water temperature and air temperature, there is a similar decrease in lake water temperature as altitude increases.  Thus, variation in water temperature implied by Δ47 could indicate changes in lake altitude, driven by tectonic uplift or subsidence. Two recent studies derive the timing of the uplift of the Andes Mountains and the Altiplano Plateau, citing sharp decreases in Δ47-derived temperatures as evidence of rapid tectonic uplift.