MET.OR.100 Meteorological data and information

GENERAL — TERMS IN PART-MET Whereas ‘provide’ is used solely in connection with the provision of MET service, ‘issue’ is used solely in connection with cases where the obligation specifically extends to sending out (disseminate) the information to a user. Furthermore, ‘supply’ is used solely in connection with cases where either ‘issue’ or ‘disseminate’ applies.

DATA AND INFORMATION RELIABILITY Owing to the variability of meteorological elements in space and time, to limitations of observing techniques, and to limitations caused by the definitions of some of the elements, the specific value of any of the elements given in a meteorological report or in a forecast is understood to be the best approximation to the actual conditions at the time of observation or the most probable value that the element is likely to assume during the period of the forecast, respectively. Similarly, when the time of occurrence or change of an element is given in a forecast, this time is understood to be the most probable time.

INFORMATION TO BE PROVIDED An agreement between the meteorological services provider and the appropriate ATS unit should be established to cover:

(a)the provision in air traffic services units of displays related to semi-automatic observing systems or automatic observing systems;

(b)the calibration and maintenance of these displays/instruments;

(c)the use to be made of these displays/instruments by air traffic services personnel;

(d)as and where necessary, supplementary visual observations, such as meteorological phenomena of operational significance in the climb-out and approach areas, if and when made by air traffic services personnel to update or supplement the information supplied by the meteorological station;

(e)meteorological information obtained from aircraft taking off or landing such as on wind shear; and

(f)if available, meteorological information obtained from ground weather radar.

OTHER AVIATION ENTITIES The competent authority determines who may be the ‘other service providers and aviation entities’ that could be provided with the necessary meteorological information.