Sea Ledger, March 2020

2020-03-01 to 2020-03-31 · archive

issued: 729
warning-days in force: 11,906
in force at month end: 369
sea × type cells: 242

baseline: same month, previous 5 years (2019-03, 2018-03, 2017-03, 2016-03, 2015-03)

By type

type	issued	warning-days	in force at end
Exercises	279	2,073.5	45
Icebergs	87	96.4	4
Incidents	80	855.8	25
Surveys	74	2,585	79
Nav aids	52	2,522	81
Missiles	34	365.9	13
Cable ops	26	424	16
Quakes	26	74.7	2
Derelicts	22	153.7	7
Other	13	441.6	17
Piracy	10	49.8	5
Debris	8	23.3	0
Spills	7	133	3
Wrecks	5	1,697.9	59
Restricted	2	129.2	5
Containers	2	6	0
Mines	1	34	1
Ordnance	1	66.4	2
Structures	0	62	2
Storms	0	18.3	0
Volcanic	0	93	3

By sea and type · 200 cells, most issued first

cell	issued	warning-days	at end	longest d	vs 5 y
Exercises · Aegean Seasurge	60	437.9	11	92	13× / 4.6
Exercises · Mediterranean Sea - Eastern Basinsurge	56	256	2	89	5.6× / 10
Exercises · North Pacific Ocean	36	237.1	8	49	1.6× / 22.4
Icebergs · Labrador Sea	31	36.8	2	32	1.9× / 16.6
Icebergs · South Atlantic Oceansurge	31	30.5	1	31	2.7× / 11.4
Exercises · Black Seasurge	30	326.6	8	124	3.3× / 9
Incidents · South China Sea	26	306.1	10	74	0.9× / 29.2
Icebergs · Southern Ocean	23	23.1	1	31	1.2× / 19
Surveys · South Atlantic Ocean	21	392.1	11	151	1.1× / 18.8
Exercises · Philippine Seasurge	14	24.9	0	—	2.2× / 6.4
Exercises · South Pacific Oceansurge	13	64.1	0	—	2.7× / 4.8
Nav aids · North Sea	12	125.9	5	71	1.0× / 12.2
Surveys · Persian Gulfsurge	9	240.1	7	308	7.5× / 1.2
Piracy · Gulf of Guineasurge	9	42.8	5	26	2.1× / 4.2
Nav aids · South Atlantic Ocean	8	204.7	6	172	0.8× / 10.4
Exercises · Mediterranean Sea - Western Basinsurge	8	90	2	89	13× / 0.6
Quakes · South Pacific Ocean	8	24.6	1	32	1.1× / 7.6
Missiles · North Pacific Ocean	7	78.1	4	201	1.0× / 6.8
Surveys · Great Australian Bightnew	7	61.6	2	43	new / 0
Exercises · Arabian Sea	7	59.7	1	32	0.8× / 8.2
Incidents · South Atlantic Ocean	7	17.8	0	—	1.3× / 5.6
Surveys · Arabian Sea	6	203.5	7	105	0.9× / 6.4
Incidents · North Pacific Ocean	6	93.3	3	45	0.3× / 23.2
Exercises · Bay of Bengal	6	44.7	1	41	0.6× / 10
Exercises · Caribbean Seasurge	6	43.1	1	32	2.7× / 2.2
Exercises · Yellow Sea	6	40	1	31	0.8× / 7.2
Quakes · North Pacific Ocean	6	15	0	—	1.3× / 4.6
Nav aids · North Atlantic Oceansurge	5	212.3	7	234	2.8× / 1.8
Nav aids · Coral Sea	5	122.8	3	280	0.7× / 7.4
Exercises · North Atlantic Ocean	5	53.3	2	62	1.1× / 4.6
Exercises · Gulf of Mexicosurge	5	38.7	0	—	3.1× / 1.6
Exercises · South Atlantic Ocean	5	36.3	1	31	0.7× / 7.2
Incidents · South Pacific Ocean	5	30.6	1	35	0.6× / 7.8
Missiles · South Pacific Oceansurge	5	20.4	0	—	2.5× / 2
Surveys · North Atlantic Oceanlong running	4	553.9	18	866	1.3× / 3.2
Missiles · Black Sea	4	101.4	4	32	1.4× / 2.8
Spills · North Pacific Oceansurge	4	94	0	—	2.5× / 1.6
Surveys · Indian Oceansurge	4	85.1	3	117	3.3× / 1.2
Surveys · Bay of Bengal	4	74	2	66	1.8× / 2.2
Incidents · Arabian Sea	4	71.2	2	36	0.9× / 4.6
Surveys · Bass Straitsurge	4	57.4	4	49	20× / 0.2
Incidents · North Atlantic Ocean	4	57	1	200	0.3× / 14.8
Other · South Pacific Oceansurge	4	48.4	3	20	2.0× / 2
Missiles · North Atlantic Ocean	4	24.3	1	32	0.4× / 10.2
Exercises · Andaman or Burma Seasurge	4	19	1	30	10× / 0.4
Incidents · Bismarck Seasurge	4	12.4	1	24	4.0× / 1
Quakes · Coral Seasurge	4	12	0	—	6.7× / 0.6
Quakes · Indian Ocean	4	10.3	1	25	1.7× / 2.4
Derelicts · Timor Seanew	4	10	0	—	new / 0
Nav aids · South Pacific Oceanlong running	3	255.7	8	512	1.4× / 2.2
Cable ops · North Atlantic Ocean	3	71	2	62	1.0× / 3
Exercises · Laccadive Sea	3	58.6	0	—	1.1× / 2.6
Incidents · Java Seasurge	3	46.6	2	39	2.5× / 1.2
Incidents · Philippine Sea	3	37.3	2	18	0.8× / 4
Derelicts · Caribbean Sea	3	25.8	2	21	1.5× / 2
Exercises · Sulu Seasurge	3	25.5	0	—	15× / 0.2
Spills · The Coastal Waters of Southeast Alaska and British Columbiasurge	3	22	3	41	3.0× / 1
Missiles · Arctic Oceansurge	3	19.9	1	15	3.8× / 0.8
Cable ops · Balearic (Iberian Sea)new	3	17.5	0	—	new / 0
Nav aids · English Channel	3	10.5	0	—	1.1× / 2.6
Debris · North Atlantic Oceansurge	3	8	0	—	3.8× / 0.8
Cable ops · Celtic Sea	3	4.6	0	—	1.3× / 2.4
Exercises · Coral Seasurge	3	4.4	0	—	2.5× / 1.2
Nav aids · North Pacific Oceanlong running	2	126	4	399	1.3× / 1.6
Surveys · South Pacific Ocean	2	121.8	4	181	2.5× / 0.8
Nav aids · Inner Seas off the West Coast of Scotland	2	72	2	110	0.5× / 4.2
Surveys · Mediterranean Sea - Western Basin	2	58	2	174	5.0× / 0.4
Nav aids · Tasman Sea	2	37.5	2	22	1.3× / 1.6
Incidents · Laccadive Sea	2	31	0	—	2.0× / 1
Surveys · North Sea	2	31	1	32	1.4× / 1.4
Cable ops · South Atlantic Ocean	2	29.7	1	113	1.1× / 1.8
Surveys · Andaman or Burma Sea	2	28.9	1	50	1.7× / 1.2
Cable ops · South China Sea	2	26.4	2	45	1.7× / 1.2
Missiles · Barentsz Sea	2	23.9	0	—	0.6× / 3.2
Exercises · Sea of Okhotsknew	2	17.2	2	8	new / 0
Cable ops · Mediterranean Sea - Western Basin	2	16.4	2	10	2.5× / 0.8
Missiles · Indian Ocean	2	15.7	1	29	1.3× / 1.6
Exercises · Gulf of Californianew	2	15.6	0	—	new / 0
Derelicts · South Atlantic Ocean	2	15	0	—	1.3× / 1.6
Exercises · South China Sea	2	14	0	—	0.8× / 2.4
Nav aids · The Coastal Waters of Southeast Alaska and British Columbia	2	12.6	1	18	2.5× / 0.8
Wrecks · East Siberian Seanew	2	9.4	2	4	new / 0
Incidents · Arafura Sea	2	8.8	0	—	5.0× / 0.4
Missiles · Labrador Seanew	2	8	0	—	new / 0
Debris · Indian Ocean	2	6.3	0	—	1.4× / 1.4
Incidents · Timor Sea	2	3.7	0	—	2.5× / 0.8
Derelicts · Gulf of Mexico	2	3.4	0	—	5.0× / 0.4
Other · Bering Sea	2	2.9	0	—	10× / 0.2
Other · Gulf of Alaska	2	2.2	1	25	10× / 0.2
Derelicts · North Atlantic Ocean	2	1.9	1	1	0.4× / 5
Cable ops · Bristol Channelnew	2	1.1	2	0	new / 0
Nav aids · Caribbean Sealong running	1	426.9	13	784	0.8× / 1.2
Surveys · Mediterranean Sea - Eastern Basin	1	146.5	5	101	0.2× / 4.4
Nav aids · Indian Ocean	1	98.4	3	362	0.6× / 1.8
Nav aids · Gulf of Mexico	1	93.4	4	68	0.3× / 3.2
Nav aids · Bass Straitlong running	1	62	2	370	1.0× / 1
Restricted · South Atlantic Ocean	1	60.4	2	89	1.3× / 0.8
Incidents · Bay of Bengal	1	42.8	1	38	1.3× / 0.8
Nav aids · Great Australian Bight	1	42.3	1	223	1.0× / 1
Cable ops · Philippine Sea	1	41.9	2	36	1.3× / 0.8
Cable ops · Bismarck Sea	1	31	1	35	new / 0
Nav aids · Arafura Sea	1	24.6	1	24	1.3× / 0.8
Cable ops · Arabian Sea	1	24.1	0	—	0.7× / 1.4
Surveys · Aegean Sea	1	23.9	0	—	1.0× / 1
Surveys · Black Sea	1	22.5	1	22	1.0× / 1
Incidents · Mediterranean Sea - Western Basin	1	19.1	0	—	1.7× / 0.6
Cable ops · Bay of Bengal	1	18.5	1	18	0.5× / 2
Incidents · Malacca Strait	1	18.1	0	—	1.7× / 0.6
Missiles · Japan Sea	1	16.4	0	—	0.6× / 1.8
Exercises · Norwegian Sea	1	16.3	0	—	new / 0
Incidents · Andaman or Burma Sea	1	15.7	1	15	new / 0
Cable ops · Gulf of Mexico	1	15.3	0	—	1.7× / 0.6
Surveys · Gulf of Guinea	1	14.7	0	—	new / 0
Incidents · Gulf of Thailand	1	14.6	0	—	0.8× / 1.2
Cable ops · Eastern China Sea	1	14.5	1	14	1.7× / 0.6
Cable ops · South Pacific Ocean	1	8.7	0	—	1.3× / 0.8
Derelicts · Inner Seas off the West Coast of Scotland	1	8.6	1	8	new / 0
Wrecks · Celtic Sea	1	8.5	1	8	new / 0
Other · Persian Gulf	1	8.2	1	8	new / 0
Exercises · Gulf of Oman	1	8	0	—	new / 0
Exercises · Japan Sea	1	7.9	0	—	1.0× / 1
Incidents · Tasman Sea	1	7.9	1	7	0.7× / 1.4
Surveys · North Pacific Ocean	1	7.5	0	—	new / 0
Cable ops · English Channel	1	7.3	0	—	2.5× / 0.4
Piracy · Singapore Strait	1	7	0	—	new / 0
Derelicts · Bismarck Sea	1	6.8	1	6	new / 0
Restricted · South Pacific Ocean	1	6.8	1	6	new / 0
Missiles · Sea of Okhotsk	1	5.6	1	5	new / 0
Missiles · South Atlantic Ocean	1	5.4	0	—	2.5× / 0.4
Wrecks · English Channel	1	5.3	1	5	1.3× / 0.8
Cable ops · Yellow Sea	1	5.1	0	—	new / 0
Missiles · Laccadive Sea	1	4.9	0	—	0.8× / 1.2
Incidents · Molukka Sea	1	4.5	0	—	1.7× / 0.6
Surveys · Celtic Sea	1	4.4	0	—	1.7× / 0.6
Ordnance · North Pacific Ocean	1	4.4	0	—	1.3× / 0.8
Incidents · Black Sea	1	4.2	0	—	new / 0
Missiles · Southern Ocean	1	3.9	0	—	new / 0
Quakes · Philippine Sea	1	3.8	0	—	1.0× / 1
Icebergs · Barentsz Sea	1	3	0	—	2.5× / 0.4
Quakes · Celebes Sea	1	3	0	—	2.5× / 0.4
Derelicts · Coral Sea	1	3	0	—	0.4× / 2.6
Derelicts · Great Australian Bight	1	3	0	—	5.0× / 0.2
Derelicts · Indian Ocean	1	3	0	—	0.7× / 1.4
Quakes · Ionian Sea	1	3	0	—	new / 0
Derelicts · Laccadive Sea	1	3	0	—	0.8× / 1.2
Other · Mediterranean Sea - Western Basin	1	3	0	—	new / 0
Derelicts · Mozambique Channel	1	3	0	—	0.8× / 1.2
Icebergs · North Atlantic Ocean	1	3	0	—	0.1× / 16
Mines · North Atlantic Ocean	1	3	0	—	new / 0
Containers · North Sea	1	3	0	—	5.0× / 0.2
Derelicts · North Sea	1	3	0	—	1.3× / 0.8
Debris · South Atlantic Ocean	1	3	0	—	2.5× / 0.4
Quakes · South Atlantic Ocean	1	3	0	—	0.8× / 1.2
Containers · South Pacific Ocean	1	3	0	—	new / 0
Debris · South Pacific Ocean	1	3	0	—	1.0× / 1
Debris · Timor Sea	1	3	0	—	5.0× / 0.2
Nav aids · Gulf of Alaska	1	2.2	0	—	0.5× / 2.2
Other · The Coastal Waters of Southeast Alaska and British Columbia	1	1.4	1	1	new / 0
Derelicts · South China Sea	1	1.2	0	—	0.7× / 1.4
Nav aids · Tyrrhenian Sea	1	1.2	0	—	new / 0
Surveys · Coral Sea	1	1.1	0	—	5.0× / 0.2
Other · Aegean Sea	1	0.9	0	—	new / 0
Wrecks · Bismarck Sea	1	0.7	1	0	new / 0
Incidents · Coral Sea	1	0.4	0	—	0.2× / 4.8
Incidents · Mediterranean Sea - Eastern Basin	1	0.1	0	—	0.1× / 17
Other · South Atlantic Ocean	1	0.1	1	0	5.0× / 0.2
Incidents · Banda Sea	1	0	0	—	2.5× / 0.4
Incidents · Great Australian Bight	1	0	0	—	2.5× / 0.4
Wrecks · South China Sealong running	0	527	17	449	0.0× / 1.4
Wrecks · Caribbean Sealong running	0	248	8	1,156	0.0× / 0.8
Other · Caribbean Sealong running	0	186	6	1,166	0.0× / 0.2
Wrecks · North Atlantic Oceanlong running	0	186	6	880	0.0× / 0.2
Wrecks · North Pacific Oceanlong running	0	124	4	1,019	— / 0
Nav aids · Arabian Sea	0	93	3	364	0.0× / 1
Exercises · Ionian Sea	0	93	3	92	0.0× / 0.2
Wrecks · Persian Gulf	0	93	3	272	0.0× / 0.8
Nav aids · Philippine Sealong running	0	93	3	391	0.0× / 0.6
Surveys · South China Sea	0	93	3	210	0.0× / 0.8
Other · Arabian Sealong running	0	62	2	429	0.0× / 0.6
Nav aids · Bering Sea	0	62	2	70	— / 0
Wrecks · Gulf of Mexicolong running	0	62	2	1,111	0.0× / 0.4
Nav aids · Mozambique Channel	0	62	2	309	0.0× / 0.6
Ordnance · North Sea	0	62	2	169	0.0× / 1
Restricted · Persian Gulf	0	62	2	349	0.0× / 0.2
Volcanic · Philippine Sea	0	62	2	106	0.0× / 0.2
Wrecks · South Atlantic Ocean	0	62	2	103	0.0× / 1
Wrecks · South Pacific Ocean	0	62	2	61	0.0× / 0.2
Surveys · Caribbean Sea	0	60	1	144	0.0× / 1.4
Other · English Channel	0	45.4	0	—	0.0× / 3.4
Surveys · Tasman Sea	0	41.9	1	96	0.0× / 0.2
Cable ops · Aegean Sea	0	31	1	131	0.0× / 0.2
Nav aids · Aegean Sea	0	31	1	364	— / 0
Missiles · Aegean Sea	0	31	1	91	0.0× / 0.2
Nav aids · Andaman or Burma Sea	0	31	1	306	0.0× / 1.2
Derelicts · Arabian Sea	0	31	1	67	0.0× / 0.8
Wrecks · Arabian Sea	0	31	1	189	0.0× / 0.2
Surveys · Arctic Ocean	0	31	1	173	— / 0
Other · Barentsz Sea	0	31	1	49	— / 0
Surveys · Beaufort Sea	0	31	1	118	— / 0
Surveys · Bering Sea	0	31	1	205	— / 0

Cite: seahazards.com Sea Ledger, 2020-03, retrieved 2026-09-03

Not for navigation. Warning-days = days each warning was in force within the month, summed. Only warnings we display are counted; the ratio compares warnings issued with the mean of the reference months.