Atmospheric Monitoring at the Pierre Auger Observatory - Status and Update

International audienceCalorimetric measurements of extensive air showers are performed with the uorescence detector of the PierreAuger Observatory. To correct these measurements for the effects introduced by atmospheric uctuations, the Observa-tory operates several instruments to record atmospheric conditions across and above the detector site. New developmentshave been made in the study of the aerosol optical depth, the aerosol phase function and cloud identication. Also,for cosmic ray events meeting certain criteria, a rapid monitoring program has been developed to improve the accuracyof the reconstruction. We present an updated overview of performed measurements and their application to air shower reconstruction