The lunar tide in the Earth's atmosphere

Abstract

1―This paper briefly summarizes the present state of our knowledge of the lunar tide in our atmosphere. It does this mainly by means of three diagrams, figs. 1, 2, and 4; figs. 2 and 4 are of novel type, while fig. 1 corrects and brings up to date, by the addition of much new material, a diagram published in my presidential address to the London Mathematical Society. 2―The lunar atmospheric tide, though of small amplitude, is of considerable theoretical interest; it presents several important unsolved problems. It was first sought for about 1774, by analysis of barometric data (for Brest) by Laplace, but with inadequate material. It was first determined in 1842 by Lefroy, for St. Helena, and a few years later by Elliot, for Singapore. Successive directors of the Batavia observatory later determined the tide from long series of their observations. All these are tropical stations, where the tide has its largest amplitude, and where the other barometic changes, from which the tide has to be disentangled by computation, are less than in higher latitudes.