�1���� Introduction
�2���� Annual median night-time field
strength
������� 2.1���� Reference time
������� 2.2���� Cymomotive force
������� 2.3���� Sea gain
������� 2.4���� Polarization coupling
loss
������� 2.5���� Slant propagation distance, p
������� 2.6���� Loss factor
incorporating effects of ionospheric absorption and related factors
������� 2.7���� Hourly loss factor
������� 2.8���� Loss factor
incorporating effect of solar activity
�3���� Day-to-day and short-period
variations of night-time field strengths
Appendix 1
List of symbols
�1���� Hourly loss factor: Lt
�2���� Sunset and sunrise times
Annex 1� Accuracy of method
Annex 2� A discussion on daytime sky-wave propagation
�1���� LF cases
�2���� MF cases
�