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The JEM-EUSO telescope will detect Ultra-High Energy Cosmic Rays\ud (UHECRs) from space, detecting the UV Fluorescence Light produced by\ud Extensive Air Showers (EAS) induced by the interaction of the cosmic\ud rays with the earth's atmosphere. The capability to reconstruct the\ud properties of the primary cosmic ray depends on the accurate measurement\ud of the atmospheric conditions in the region of EAS development. The\ud Atmospheric Monitoring (AM) system of JEM-EUSO will host a LIDAR,\ud operating in the UV band, and an Infrared camera to monitor the cloud\ud cover in the JEM-EUSO Field of View, in order to be sensitive to clouds\ud with an optical depth tau a parts per thousand yen 0.15 and to measure\ud the cloud top altitude with an accuracy of 500 m and an altitude\ud resolution of 500 m

EUSO-TA is a ground-based florescence detector built to validate the design of an ultra-high energy cosmic ray fluorescence detector to be operated in space. EUSO-TA detected the first air shower events with the technology developed within the JEM-EUSO program. It operates at the Telescope Array (TA) site in Utah, USA. With the external trigger provided by the Black Rock Mesa fluorescence detectors of Telescope Array (TA-FDs), EUSO-TA observed nine ultra-high energy cosmic ray events and several laser events from the Central Laser Facility of Telescope Array and portable lasers like the JEM-EUSO Global Light System prototype. The reconstruction parameters of the cosmic ray events which crossed the EUSO-TA field of view (both detected and not detected by EUSO-TA), were provided by the Telescope Array Collaboration. As the TA-FDs have a wider field of view than EUSO-TA (∼30 times larger), they allow the cosmic ray energy reconstruction based on the observation of most of the extensive air-shower profiles, including the shower maximum, while EUSO-TA only observes a portion of the showers, usually far from the maximum. For this reason, the energy of the cosmic rays corresponding to the EUSO-TA signals appear lower than the actual ones. In this contribution, the analysis of the cosmic-ray events detected with EUSO-TA is discussed.