Pre-satellite weather balloons

John Brown and Emmett Pybus are shown here conducting upper-atmospheric water-vapor studies in Antarctica. Brown and Pybus were meteorologists working for the US Army’s Ballistic Research Laboratories, Aberdeen Proving Ground, Maryland, in the 1960s. Their studies involved flying balloons equipped with dew-point hygrometers to measure the water-vapor profiles at different layers of the atmosphere. Before the late 1960s, few satellites were collecting meteorological data, so the hygrometers provided a majority of information about the upper atmosphere. This balloon would ultimately travel more than 32 kilometers aboveground.

Although meteorological studies are conducted all over the world, Antarctica is a unique environment. The upper atmosphere at the poles differs from that in the middle latitudes because of magnetic field differences. Also, the angle at which solar radiation hits the surface affects the amount of water that evaporates into the atmosphere. The Arctic Ocean has seasonal sea ice, but Antarctica is covered by a year-round solid shelf of ice, making it a more permanent location from which the atmosphere can be measured from the ground. This photo and additional ones of Antarctic researchers can be found at the Emilio Segrè Visual Archives of the American Institute of Physics (publisher of Physics Today). A 2015 oral history with Pybus is available in the Oklahoma State University Library digital collection as part of its oral history research program (https://dc.library.okstate.edu/digital/collection/ostate/id/8934 ).