synotic charts: they are the weather charts for the present condition movement and patterns of air pressure, rainfall, wind and temperature. This information is conveyed using symbols, which are explained in a legend.
prognosis chart: these are also the weather chart but with future prediction , it gives information regarging wind ,pressure , rain which is likely to be encountered in the next 24 hr, 48 hrs and 72 hours
correct me if i am wrong.....
harmonised system of survey n certification.
to ease out with survey n survey dates, helps in cost control, ease out survey planning and unwanted delay of the service period of the ship.