April 5, 1646 Tsunami: Livorno, Italy

Name: April 5, 1646 Tsunami: Livorno, Italy
Start: 1646-04-05
Location: Livorno, Italy

April 5, 1646 · Definite tsunami

A tsunami caused by a magnitude 5.2 earthquake began at Livorno, Italy on April 5, 1646 at 20:00 UTC. Its effects were recorded at 1 place.

Where the waves reached

The source (white) and every runup with a place, colored by the water height recorded there. A ring is a runup NCEI marks doubtful.

Under 1 m
1 to 3 m
3 to 10 m
10 to 30 m
30 m and more
Height not recorded

Tsunami warnings in force

Travel times

How long the first wave took to reach each part of the ocean, one line for each hour up to 24, estimated from the source and the depth of the sea.

The travel times are computed in your browser, which needs JavaScript.

1 to 4 hours
5 to 6 hours
7 to 14 hours
15 hours and more

Computed in your browser the way NOAA’s own travel time maps are: the wave travels at the square root of gravity times the depth, over NOAA’s ETOPO1 depths averaged to a 10 arc-minute grid. Checked against NOAA NCEI’s maps for 21 tsunamis over the first 24 hours, these lines fall within 10 minutes of NCEI’s at half the points compared and within 52 minutes at 9 in 10. They give when the first wave could arrive, not how high it is; bays, harbors and island chains finer than the grid can see it later. Not for use in a warning: see tsunami.gov.

The tsunami

Date: April 5, 1646, 20:00 UTC
Source: Livorno, Italy
Cause: Earthquake
Earthquake: Magnitude 5.2
Runups recorded: 1
Tsunami intensity (Soloviev-Imamura): 3
Waters: Ocean
How certain: Definite tsunami
Source location: 43.550° N, 10.317° E

The toll

Damage: Moderate (about $1 to $5 million) with the earthquake or eruption that caused it
Houses damaged: Many (101 to 1,000) with the earthquake or eruption that caused it

Where the literature gives no number, NCEI records a description on a scale of 1 to 4, printed here in its words. Damage is in millions of US dollars of the year of the event, not adjusted for inflation.

What the record says

NCEI’s account, from the sources it cites.

1846, April 5, around 20h. Italy, Livorno. 43o30'N, 10o5'E, earthquake intensity VIII, tsunami intensity 3. At first a sudden momentary boom was heard coming from the sea. Then a strong earthquake shook houses with a great force. Ships in the harbour experienced such strong blows that they seemed to be beaten against the sea bottom. Questionable tsunami? (reference #2130).

1646, April 5. Tuscany, 43o33'N, 10o19'E, magnitude 5.2, earthquake intensity 7, tsunami intensity 3, reliability 4. Strong earthquake in Livorno. Many buildings suffered severe damage. Sea level rising more than 3 yards (Settimani, r85). In the harbour some ships grounded (Pilla, r86).

Further references: Mallet (r33), Capocci (r34), Mercalli (r13), Baratta (r1), Carrozzo (r41), Caputo (r5), Tinti (9, r597), Boschi (r604).

(reference #4139)

Every runup

Nearest the source first. Heights are above sea level at the time; a tide gauge reads half the wave’s full height.

Where	Country	Km from source	Water height, m	Inland, m	Measured by	First wave, UTC	Deaths
Livorno	Italy	1			Eyewitness observation of water height

Every tsunami in 1646 The 1600s Tsunamis of Italy The earthquake This day in weather history Alerts in force

Sources

Tsunami events and runups from NOAA’s National Centers for Environmental Information, Global Historical Hazard Database, cited as NCEI/WDS, doi:10.7289/V5PN93H7. Public domain. Read 2026-10-01. NCEI tsunami event 3133.