Comparison of the Vertical Motions of Paired Tetroon Flights

Abstract

Pairs of constant volume balloons (tetroons) released ?1 min apart from the same site at Haswell, Colo., and continuously tracked by two M-33 radars, are used to estimate the mutual consistency of tetroon vertical motions. In the strong well-organized vertical motion systems of midday and afternoon, it is possible unambiguously to relate the vertical oscillations of the two tetroons so long as the tetroon separation distance is less than about 3 km, implying that under these conditions the tetroons are indeed passing through the same systems (convection cells or thermals). At other times of day such a comparison becomes difficult, partly because of the smaller amplitude and period of oscillation. Where identification of the same vertical motion system is possible, the phase lag between vertical oscillations of adjacent tetroons is related in a meaningful way to the tetroon spacing and the relative position of the tetroon pair with respect to wind direction, and accordingly there is good evidence that tetroon vertical motions are basically consistent.