Estimation of integrated water vapor derived from Global Navigation Satellite System observations over Central-Western Argentina (2015?2018). Validation and usefulness for the understanding of regional precipitation events

M.F. CAMISAY; J.A. RIVERA; M.L. MATEO; P.V. MORICHETTI; M.V. MACKERN; M.V.MACKERN

JOURNAL OF ATMOSPHERIC AND SOLAR-TERRESTRIAL PHYSICS

ELSEVIER

Lugar: Amsterdam; Año: 2020 vol. 197 p. 105 - 143

1364-6826

Water vapor plays a crucial role in atmospheric processes that act over a wide range of temporal and spatial scales. Its knowledge is fundamental in investigations that are undertaken in both climatology and meteorology. Its quantification plays a major role in the development, understanding and forecasting of any extreme precipitation event to be studied. The integrated water vapor (IWV) knowledge requires a permanent measurement and as much as possible from a wide network that ensures spatial monitoring. This kind of measurements can be obtained through and indirect technique based on the tropospheric delay calculated in the GNSS stations, complementing the water vapor measurements from the scarse direct radiosonde observations available in Latin America. Considering the impacts of regional heavy precipitation events, this study addressed the capability of GNSS stations to derive IWV fluctuations along the Central-Western Argentina, a semi-arid region with complex topography. A good agreement (r2 > 0.9) was observed between IWVGNSS and observations from radiosonde measurements, highlighting the capability of the GNSS stations to provide IWV estimations for a denser network. The comparison of the variability of the IWV estimations, the atmospheric pressure and precipitation totals for a case study showed that the occurrence of large IWV values (positive IWV anomalies) preceded abundant precipitation along the CWA, in conjunction with the presence of mid-troposphere low pressure anomalies acting as synoptic forcing. This kind of information provides a more comprehensive picture about the atmospheric processes involved in the development of deep convection and can be used for the development of contingency plans in the region, considering the difference in the timing between positive IWV anomalies both on site and in its vicinity and heavy precipitation events.