Re. “Frequency analysis of Tide Data from Port Arthur, Tasmania”:

1. “According to John Hunter (pictured below with the mark), this is because Lempriere actually put the mark above high tide so as to avoid too much wave erosion.”

Wrong – I never said anything like this. If you think I did please provide evidence – otherwise it might be a good idea to correct your article.

2. “Since I had a gap and intended to use Fourier Analysis ……”

Anyone who deals with time series which have spectra with quite discrete lines that are non-harmonic will tell you that Fourier Analysis is a rather dumb way to go – it induces significant spectral spreading and shifting.

3. “However the resonance marked as “X” does not correspond to any astronomical forcing ….. so I surmise that X corresponds to the tidal constant of the estuary ….. the sea washes in and out of the harbour every 23 hours and 37 minutes.”

Rubbish – you’ve made a clear numerical error. Simply measuring the ratio between the frequencies of “X” and O1 on your graph shows a ratio that is within less than 0.1% of the ratio between the frequencies of K1 and O1. On the other hand, the ratio between the frequencies of an “X” with a period of 23 hours and 37 minutes and O1 differs from the ratio estimated from your graph by around 3%. “X” is K1, no question. If not, then where on Earth has K1 (one of the dominant tidal constituents in this region) gone? Before you did this, did you even bother to look at tidal analyses of other sites in this region?

Sorry John – back to the drawing board …..

Best of luck with the blog – looks like 3.6 hits / day 😉

Re. “Frequency analysis of Tide Data from Port Arthur, Tasmania”:

1. “According to John Hunter (pictured below with the mark), this is because Lempriere actually put the mark above high tide so as to avoid too much wave erosion.”

Wrong – I never said anything like this. If you think I did please provide evidence – otherwise it might be a good idea to correct your article.

2. “Since I had a gap and intended to use Fourier Analysis ……”

Anyone who deals with time series which have spectra with quite discrete lines that are non-harmonic will tell you that Fourier Analysis is a rather dumb way to go – it induces significant spectral spreading and shifting.

3. “However the resonance marked as “X” does not correspond to any astronomical forcing ….. so I surmise that X corresponds to the tidal constant of the estuary ….. the sea washes in and out of the harbour every 23 hours and 37 minutes.”

Rubbish – you’ve made a clear numerical error. Simply measuring the ratio between the frequencies of “X” and O1 on your graph shows a ratio that is within less than 0.1% of the ratio between the frequencies of K1 and O1. On the other hand, the ratio between the frequencies of an “X” with a period of 23 hours and 37 minutes and O1 differs from the ratio estimated from your graph by around 3%. “X” is K1, no question. If not, then where on Earth has K1 (one of the dominant tidal constituents in this region) gone? Before you did this, did you even bother to look at tidal analyses of other sites in this region?

Sorry John – back to the drawing board …..

Best of luck with the blog – looks like 3.6 hits / day 😉