The Precipitable Water Vapor Column of the Atmosphere on the region above Mexico City

• DOI: 10.22533/at.ed.2892324087

• Palavras-chave: -

• Keywords: precipitable wáter vapor, infrared wavelength, meteorological sondes

• Abstract: In this work we present the results of the analysis of data taken with radio sondes to estimate the atmospheric water vapor content over the region of Mexico City. The water vapor in the atmosphere, integrated in altitude is referred to as Precipitable Water Vapor (PWV), it is an important factor to determine the opacity of the atmosphere for astronomical observations at mm and IR wavelengths. The aim is to identify feasible periods for astronomical observations at locations of the center of Mexico. Also, we want to compare the PWV at mid altitudes with that for high altitudes. With this purpose, the PWV is estimated by calculating the PWV from various lower limits up to the highest altitude where the sonde takes data (about 20 km). We take 2.0 km as the lowest value for the lower limit of integration. The next lower limit is 2.5 km, and so on. The largest lower limit is 6.0 km. Histograms of PWV obtained for different values of lower limit of integration have been made. The histograms for high altitude lower limits (5.5-6.0 km) have prominent maxima at low values of PWV. The maximum, shifts to larger values of PWV as the lower limit of integration decreases, besides that, as going to lower limits of integration, the PWV spreads more to low values. The spread is larger for Winter time than the Summer one. As a consequence, the PWV, integrated from the altitude of Mexico City (2-2.5 km), has values as low as those observed when integrating from lower limits of 5-6 km altitude. It means, the water vapor content at the region of Mexico City are feasible for Astronomical observations during Winter time.