Atmospheric temperature profiles at the Antarctic node of LAGO: Quiet and perturbed conditions

A.M GULISANO; S. DASSO; O. ARESO; M. PEREIRA

Ostend

Congreso; 14 European Space Weather Week; 2017

The Latin American Giant Observatory (LAGO) is a collaborative network formed by ten countries (Argentina, Bolivia, Colombia, Chile, Ecuador, Guatemala, Mexico, Perú, Venezuela, and Brazil). LAGO has a Space Weather program and one of its main aims is to study the modulation of variability of Cosmic Rays (CRs) using its net of Water Cherenkov Detector (WCDs) and making numerical simulations of the transport of CRs in different physical scenarios. LAGO plans to deploy WCDs at the Antarctic peninsula, in the Argentinean Marambio base. Observations at this node will help to make scientific studies and also to make a monitoring of space weather conditions. Due to the low rigidity cut-off of this high latitude site, observations of Ground Level Enhancements (GLEs) will be possible. In order to carry out numerical simulations to better understand the ground observations of the CRs fluxes, is necessary to characterize the atmosphere, where the secondary particles are created during the extended CRs shower. In this work, we present a characterization of the atmospheric conditions at the Argentinean Marambio base, where the Antarctic LAGO node will be deployed. In particular, we analyze the temperature altitude profile in a range covering the upper troposphere, and the low-mid stratosphere, for quiet conditions and during two major geomagnetic storms, the seasonal climatology of temperatures and investigated possible variations during five intense geomagnetic storms and the possibility of physical and chemical effects during these events. We analyze data obtained from balloon surveys measured at Marambio by the National Meteorological Service of Argentina from 1998 to 2016. We present the seasonal behavior, of the temperature variable environment from 8 to 40 km throughout the period, and analyze the median and quartile statistics during two geomagnetic storms: one in summer and one in winter, extending the analysis period to seven days prior to the occurrence of the storms and to the fourteen subsequent days. In addition, given the different values of the Dst index, we calculated the temperature anomalies, for each geomagnetic storm and the subsequent days, and we also obtained the degrees of cooling and heating, relative to the days prior to the five events.The results of this study will be useful to better understand the possible events of Space Weather and, on the other hand, will also be very useful to make corrections to the flow of cosmic rays, which will be observed in the near future with the particle detector of LAGO to study the solar modulation of the cosmic ray flux and GLE events, in the site with the lower rigidity cut off of this observatory.