Atmospheric radiosonde sampling with the height

The Mexico City and its surroundings are at altitudes of 2,000 meters over sea level (m.o.s.l). Here, the weather is mild, but in the last years, the temperatures have been increased gradually and it has been quite perceptible over time. The Water Vapor Content (WVC) of the atmosphere plays a major role in the greenhouse effect. Since, the behavior of the H2O molecular density with height is similar to an exponential function, the greatest contributions to the integrated WVC comes from the lower layers of the atmosphere. However, locally, in a given interval of heights, this trend may invert, presenting an increase in density and temperature. There may be variations in meteorological parameters that could occur on short height intervals but due to irregular samplings during the ascend of the radiosondes, these variations could pass unnoticed. In this work, we study the sampling frequency with height as well as the atmospheric data, measured by meteorological probes or radiosondes from Mexico City and the city of Veracruz. We made histograms using bines of sizes ranging from 0.01 to 1.00 Km, where it can be seen that there are some height intervals where the sampling frequency with height is non-homogeneous. In some heights, for example, at 1,520 and 3,160 m.o.s.l., it is observed interesting variations in the temperature gradient as well as in the density of water vapor. This temperature inversions, as well as the gradient variations could be identified because of the high number of radiosondes records made over time.