Ir al menú de navegación principal Ir al contenido principal Ir al pie de página del sitio

Articles

1985: Vol. LXII, No. 1

Tidal Prediction and Modern Time Scales

Enviado
julio 31, 2015
Publicado
2015-07-16

Resumen

Modern time scales introduced since about 1950 and revised formulae for the mean lunar and solar longitudes are defined and compared with the formulae of Newcomb (1895) and Brown (1919), which still form the basis of current tide prediction practice. Changes in tidal arguments of order 0°.02 are identified, with a tendency to increase towards the 21st century. Small changes in potential amplitude and speed of some leading harmonic constituents from AD 1900 to 2000 are also noted. While all changes are small by tidal standards, it is recommended that the modern formulae be adopted by tidal authorities before discrepancies become noticeable. The modern formulae require at least an approximate correction for the difference between Dynamic or Ephemeris Time and Civil or Universal Time, which will probably exceed 1 minute before AD 2000.