The KM3NeT neutrino telescope, currently under construction, aims to detect high energy neutrinos from distant astrophysical sources, as well as studying the properties of neutrinos by exploiting...Show moreThe KM3NeT neutrino telescope, currently under construction, aims to detect high energy neutrinos from distant astrophysical sources, as well as studying the properties of neutrinos by exploiting atmospheric neutrinos. 3-Dimensional arrays of thousands of optical sensors with a total volume of about five cubic kilometres will be distributed over three locations in the Mediterranean Sea. These optical sensor modules will detect the cherenkov light emitted by the charged particles (muons) produced in collisions of neutrinos and the Earth. To be able to reconstruct the path of the muons radiating the detected photons, an accurate time-calibration is vital. For efficient commissioning, already before deployment a pre-timecalibration of the modules is required. Currently, a laser-installation is used to perform this calibration procedure. In this thesis the possibility to use cosmic ray showers to perform this pre-calibration is investigated. Particles (muons, electrons) of secondary radiation reaching the earth in an air shower will hit the detectors at virtually the same moment, which makes the recorded coincident suitable for time-calibration. This study demonstrates that the optical modules can indeed detect these particles from cosmic showers, and that the subsequent data can be exploited for a robust time-calibration with an accuracy of within 0.3 ns.Show less