Period

Duration effective

Instrument

Frequency

Unit measurement

System

Type archives

Source

1912

3 months

Tide scale

30 min.

Metric

Time

Universal

Register

SHOM (Brest

1928

9 days

Medimeter

1 day

Metric

Time

Universal

Register

SHOM (Brest)

1949

1 month

Tide scale

Diurnal-15 min.

Metric

Time

Universal

Register

SHOM

(Brest)

1950

1 year

Shiny tide gauge

2 hours

Metric

Time

Universal

Telegram

SHOM

(Brest)

1951-1954

4 years

Float tide gauge

10 min.

Metric

Time

Universal

Telegram

SHOM

(Brest)

1964-1965

2 years

Tide gauge float switch

10 min.

Metric

Time

Universal

Telegram

DDH

PAA

1974-2011

37 years old

Tide gauge

float switch

10 min.

Metric

Time

Universal

Telegram

DDH

PAA

2012-2016

5 years

Tide gauge digital

10 min.

Metric

Time

Universal

Data

digital

DDH

PAA