Sea Ledger, May 2020

2020-05-01 to 2020-05-31 · archive

issued: 659
warning-days in force: 10,622
in force at month end: 323
sea × type cells: 213

baseline: same month, previous 5 years (2019-05, 2018-05, 2017-05, 2016-05, 2015-05)

By type

type	issued	warning-days	in force at end
Exercises	209	1,486.3	38
Incidents	94	794.3	28
Icebergs	94	103.1	4
Nav aids	51	2,419.8	73
Surveys	51	2,041.3	60
Missiles	38	370.8	10
Quakes	28	76.6	4
Cable ops	24	375	11
Derelicts	22	100.1	2
Spills	11	163	6
Other	10	334.7	13
Piracy	10	62.7	0
Containers	7	20.7	0
Wrecks	4	1,841.1	60
Ordnance	3	93	3
Debris	2	36	1
Restricted	1	165.1	6
Structures	0	31	1
Mines	0	14.7	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
Icebergs · Southern Oceansurge	62	63.9	2	31	4.3× / 14.6
Exercises · Mediterranean Sea - Eastern Basinsurge	50	331.9	3	150	4.7× / 10.6
Exercises · North Pacific Ocean	33	158.8	3	49	1.5× / 21.6
Icebergs · Labrador Seasurge	31	36.2	2	32	3.2× / 9.8
Exercises · Black Seasurge	26	205.4	8	94	2.5× / 10.6
Incidents · South China Sea	25	292.7	11	135	1.1× / 22.2
Exercises · Aegean Seasurge	24	268.5	8	153	6.3× / 3.8
Incidents · North Pacific Ocean	13	127.7	2	49	0.6× / 23.6
Missiles · North Atlantic Ocean	12	34.9	1	19	1.3× / 9.2
Derelicts · South Atlantic Oceansurge	12	20.9	0	—	5.5× / 2.2
Nav aids · South Atlantic Ocean	10	373	11	88	1.1× / 9.2
Exercises · Yellow Sea	10	58.5	2	37	1.0× / 10
Cable ops · North Atlantic Ocean	10	56	2	91	1.9× / 5.4
Exercises · South Atlantic Ocean	10	48.7	0	—	1.7× / 5.8
Surveys · South Atlantic Ocean	9	200.6	5	124	0.7× / 12.6
Exercises · Mediterranean Sea - Western Basinnew	9	79.3	1	150	new / 0
Missiles · South Pacific Oceansurge	9	25.4	1	19	7.5× / 1.2
Piracy · Gulf of Guineasurge	8	48.7	0	—	3.6× / 2.2
Exercises · South Pacific Ocean	8	19.3	2	36	1.3× / 6.4
Nav aids · Caribbean Seasurgelong running	7	189.2	6	845	5.0× / 1.4
Incidents · South Pacific Ocean	7	22.4	1	44	1.0× / 7.2
Quakes · South Pacific Ocean	7	18	1	24	0.8× / 8.6
Surveys · Arabian Sea	6	199.2	6	87	1.0× / 6
Incidents · Indian Ocean	6	37.4	1	27	0.9× / 6.8
Containers · Tasman Seanew	6	17.7	0	—	new / 0
Nav aids · South Pacific Oceansurgelong running	5	262.2	8	573	2.5× / 2
Surveys · Persian Gulfsurgelong running	5	151.9	4	369	5.0× / 1
Nav aids · North Pacific Oceanlong running	5	138.4	4	460	1.6× / 3.2
Nav aids · Coral Sea	5	97	3	341	0.6× / 8.2
Surveys · Mediterranean Sea - Eastern Basin	5	84.6	2	162	1.4× / 3.6
Exercises · Arabian Sea	5	78.8	4	32	0.7× / 6.8
Nav aids · North Sea	5	74.4	2	80	0.7× / 7
Surveys · Mediterranean Sea - Western Basinsurge	5	68.3	1	31	13× / 0.4
Exercises · North Atlantic Ocean	5	32.1	1	31	1.0× / 5.2
Incidents · Arabian Seasurge	5	29.3	3	16	2.1× / 2.4
Exercises · Bay of Bengal	5	19.8	1	18	0.7× / 7.6
Incidents · South Atlantic Ocean	5	19.8	0	—	0.9× / 5.8
Quakes · North Pacific Ocean	5	13.2	1	27	0.8× / 6.6
Surveys · North Atlantic Oceanlong running	4	540.7	17	927	0.7× / 5.8
Missiles · Black Sea	4	164.7	4	35	1.2× / 3.4
Incidents · Eastern China Sea	4	58.6	1	21	1.7× / 2.4
Spills · North Pacific Ocean	4	58	3	45	0.8× / 4.8
Spills · North Atlantic Ocean	4	57	1	45	1.5× / 2.6
Incidents · North Atlantic Ocean	4	50.4	3	261	0.2× / 17.2
Surveys · Ligurian Seanew	4	33.6	0	—	new / 0
Missiles · Indian Oceansurge	4	15.4	0	—	2.0× / 2
Exercises · Caribbean Seasurge	4	13.5	0	—	2.0× / 2
Quakes · Coral Seasurge	4	12	0	—	2.2× / 1.8
Exercises · Gulf of Mexicosurge	4	4.1	0	—	2.0× / 2
Missiles · North Pacific Ocean	3	52.3	1	262	0.5× / 6.6
Incidents · Caribbean Sea	3	51.1	2	19	0.7× / 4.2
Spills · Gulf of Mexico	3	48	2	36	0.5× / 6
Cable ops · North Pacific Oceansurge	3	47.5	1	30	3.8× / 0.8
Other · English Channelsurge	3	31.9	2	26	3.0× / 1
Missiles · Barentsz Sea	3	25.5	1	36	0.8× / 3.6
Exercises · Barentsz Sea	3	11.8	0	—	1.7× / 1.8
Incidents · Black Seanew	3	10.9	0	—	new / 0
Quakes · Mediterranean Sea - Eastern Basinnew	3	9	0	—	new / 0
Derelicts · North Atlantic Ocean	3	8.9	0	—	0.9× / 3.2
Incidents · Philippine Sea	3	7.6	0	—	0.7× / 4.4
Exercises · Coral Seasurge	3	7.1	0	—	3.8× / 0.8
Nav aids · Irish Sea and St. George's Channelsurge	3	6.4	1	17	2.1× / 1.4
Exercises · Philippine Sea	3	5.1	0	—	1.0× / 3
Nav aids · North Atlantic Ocean	2	220.1	6	295	0.3× / 6.2
Nav aids · Arabian Sealong running	2	110.2	4	425	0.7× / 3
Cable ops · Philippine Seanew	2	32	0	—	new / 0
Cable ops · Aegean Sea	2	25.5	1	37	5.0× / 0.4
Ordnance · South Pacific Oceannew	2	25	1	25	new / 0
Exercises · Laccadive Sea	2	23.7	1	25	1.1× / 1.8
Missiles · Japan Sea	2	19.4	1	30	0.9× / 2.2
Exercises · Andaman or Burma Sea	2	15.1	0	—	1.7× / 1.2
Quakes · Banda Sea	2	6	0	—	10× / 0.2
Quakes · Indian Ocean	2	6	0	—	2.0× / 1
Derelicts · Mediterranean Sea - Eastern Basin	2	4	0	—	2.0× / 1
Incidents · Coral Sea	2	2.7	0	—	0.6× / 3.2
Incidents · Timor Sea	2	0.4	0	—	2.0× / 1
Wrecks · Persian Gulf	1	140.3	5	333	2.5× / 0.4
Surveys · South Pacific Ocean	1	93	3	242	new / 0
Wrecks · South Atlantic Ocean	1	90.6	3	164	1.0× / 1
Surveys · Black Sea	1	76.5	2	83	0.8× / 1.2
Restricted · South Atlantic Ocean	1	72.1	3	150	5.0× / 0.2
Cable ops · South China Sea	1	72	3	83	1.3× / 0.8
Other · South Pacific Ocean	1	66.8	2	81	1.7× / 0.6
Nav aids · Mozambique Channellong running	1	62	2	370	1.0× / 1
Surveys · Norwegian Sea	1	51.5	1	41	0.5× / 2
Surveys · North Sea	1	50.7	2	34	0.3× / 3
Nav aids · Inner Seas off the West Coast of Scotland	1	47.2	2	171	0.3× / 3
Cable ops · Indian Ocean	1	42.8	2	272	2.5× / 0.4
Nav aids · Tasman Sea	1	39.8	1	83	0.8× / 1.2
Surveys · Sea of Okhotsk	1	36.6	2	55	1.3× / 0.8
Cable ops · Mediterranean Sea - Eastern Basin	1	35.6	0	—	0.7× / 1.4
Nav aids · English Channel	1	32.4	0	—	0.3× / 3.6
Nav aids · Arafura Sea	1	31.8	2	85	1.3× / 0.8
Surveys · Tyrrhenian Sea	1	31.4	1	51	new / 0
Nav aids · Mediterranean Sea - Western Basin	1	31.1	2	131	1.3× / 0.8
Nav aids · Norwegian Sea	1	31	1	51	5.0× / 0.2
Surveys · Gulf of Mexico	1	26.3	1	26	1.0× / 1
Cable ops · Arabian Sea	1	17.2	0	—	0.6× / 1.6
Surveys · Mozambique Channel	1	14.9	0	—	5.0× / 0.2
Surveys · Celtic Sea	1	13.4	1	13	0.6× / 1.6
Surveys · Indian Ocean	1	12.7	0	—	1.0× / 1
Incidents · Gulf of Tomini	1	12.2	1	12	new / 0
Cable ops · Celtic Sea	1	11.8	0	—	2.5× / 0.4
Derelicts · Singapore Strait	1	11.7	0	—	new / 0
Derelicts · Indian Ocean	1	10.7	1	10	0.2× / 4.2
Incidents · Celebes Sea	1	10.6	0	—	new / 0
Cable ops · Solomon Sea	1	10.4	1	10	new / 0
Incidents · Arafura Sea	1	8.9	1	8	1.7× / 0.6
Surveys · Gulf of Suez	1	7.7	1	7	5.0× / 0.2
Incidents · Mozambique Channel	1	7.4	1	7	1.3× / 0.8
Other · North Pacific Ocean	1	7.4	1	7	0.8× / 1.2
Piracy · Gulf of Aden	1	7	0	—	0.7× / 1.4
Piracy · Singapore Strait	1	7	0	—	5.0× / 0.2
Incidents · Banda Sea	1	6.6	0	—	1.0× / 1
Cable ops · North Sea	1	6.6	1	6	0.6× / 1.8
Ordnance · North Pacific Ocean	1	6	0	—	new / 0
Other · Persian Gulf	1	5.7	1	69	new / 0
Exercises · Norwegian Sea	1	4.7	0	—	0.6× / 1.8
Wrecks · Andaman or Burma Sea	1	4.6	1	4	new / 0
Exercises · Japan Sea	1	3.6	1	3	5.0× / 0.2
Surveys · Ionian Sea	1	3.5	0	—	new / 0
Surveys · Japan Sea	1	3.5	1	3	1.7× / 0.6
Exercises · Persian Gulf	1	3.5	0	—	5.0× / 0.2
Other · The Coastal Waters of Southeast Alaska and British Columbia	1	3.2	0	—	new / 0
Debris · Bay of Bengal	1	3	0	—	new / 0
Quakes · Eastern China Sea	1	3	0	—	2.5× / 0.4
Containers · Great Australian Bight	1	3	0	—	new / 0
Derelicts · Gulf of Mexico	1	3	0	—	0.8× / 1.2
Incidents · Gulf of Mexico	1	3	0	—	0.3× / 4
Derelicts · Laccadive Sea	1	3	0	—	5.0× / 0.2
Icebergs · Laptev Sea	1	3	0	—	new / 0
Quakes · South Atlantic Ocean	1	3	0	—	0.5× / 2.2
Derelicts · South Pacific Ocean	1	3	0	—	0.6× / 1.6
Quakes · Tasman Sea	1	3	0	—	5.0× / 0.2
Incidents · Bismarck Sea	1	2.4	0	—	2.5× / 0.4
Missiles · South China Sea	1	2.2	0	—	5.0× / 0.2
Wrecks · Bay of Bengal	1	2	0	—	new / 0
Quakes · North Atlantic Ocean	1	1.9	1	1	2.5× / 0.4
Quakes · Philippine Sea	1	1.5	1	1	0.3× / 3
Debris · South Pacific Ocean	1	1.5	0	—	1.3× / 0.8
Other · Hudson Bay	1	0.9	0	—	new / 0
Incidents · Makassar Strait	1	0.7	0	—	5.0× / 0.2
Incidents · Bali Sea	1	0.5	0	—	new / 0
Other · North Atlantic Ocean	1	0.3	0	—	0.3× / 3
Other · Arafura Sea	1	0.2	0	—	2.5× / 0.4
Incidents · Andaman or Burma Sea	1	0	0	—	5.0× / 0.2
Incidents · Celtic Sea	1	0	0	—	new / 0
Incidents · North Sea	1	0	0	—	new / 0
Wrecks · South China Sealong running	0	527	17	510	0.0× / 1
Wrecks · Caribbean Sealong running	0	248.4	8	1,217	0.0× / 0.2
Wrecks · North Atlantic Oceanlong running	0	186	6	941	— / 0
Wrecks · North Pacific Oceanlong running	0	124	4	1,080	— / 0
Nav aids · Gulf of Mexico	0	119.1	2	129	0.0× / 3.6
Other · Caribbean Sealong running	0	94.3	3	1,227	— / 0
Nav aids · Indian Oceanlong running	0	93	3	423	0.0× / 2.2
Exercises · Ionian Sea	0	93	3	153	— / 0
Nav aids · Philippine Sealong running	0	93	3	452	0.0× / 0.2
Surveys · South China Sea	0	93	3	271	0.0× / 1
Other · Arabian Sealong running	0	62	2	490	0.0× / 0.6
Nav aids · Bass Strait	0	62	2	162	0.0× / 1.4
Surveys · Bass Strait	0	62	2	64	0.0× / 0.2
Wrecks · East Siberian Sea	0	62	2	65	— / 0
Wrecks · Gulf of Mexicolong running	0	62	2	1,172	0.0× / 0.2
Ordnance · North Sea	0	62	2	230	0.0× / 3.6
Nav aids · Persian Gulf	0	62	2	47	0.0× / 0.2
Restricted · Persian Gulflong running	0	62	2	410	— / 0
Volcanic · Philippine Sea	0	62	2	167	0.0× / 0.2
Wrecks · South Pacific Ocean	0	62	2	122	0.0× / 0.8
Surveys · Sea of Marmara	0	38.6	1	139	— / 0
Nav aids · Bay of Bengal	0	31.9	1	44	0.0× / 0.4
Missiles · Aegean Sea	0	31	1	152	0.0× / 0.8
Nav aids · Andaman or Burma Sealong running	0	31	1	367	0.0× / 0.8
Derelicts · Arabian Sea	0	31	1	128	0.0× / 0.2
Wrecks · Arabian Sea	0	31	1	250	0.0× / 0.2
Surveys · Arctic Ocean	0	31	1	234	— / 0
Surveys · Beaufort Sea	0	31	1	179	— / 0
Surveys · Bering Sea	0	31	1	266	— / 0
Other · Black Sea	0	31	1	215	— / 0
Wrecks · English Channel	0	31	1	66	0.0× / 0.2
Nav aids · Great Australian Bight	0	31	1	284	0.0× / 0.4
Surveys · Great Australian Bight	0	31	1	87	— / 0
Wrecks · Great Australian Bight	0	31	1	356	— / 0
Wrecks · Gulf of Californialong running	0	31	1	593	— / 0
Wrecks · Gulf of Guinea	0	31	1	242	0.0× / 1
Nav aids · Gulf of Thailand	0	31	1	227	0.0× / 0.2
Wrecks · Gulf of Thailand	0	31	1	141	— / 0
Wrecks · Indian Oceanlong running	0	31	1	398	— / 0
Incidents · Java Sea	0	31	1	83	0.0× / 1
Nav aids · Laccadive Sealong running	0	31	1	394	0.0× / 1.2
Nav aids · Mediterranean Sea - Eastern Basin	0	31	1	289	0.0× / 0.2
Wrecks · Mediterranean Sea - Eastern Basin	0	31	1	144	— / 0
Volcanic · Mozambique Channel	0	31	1	241	— / 0
Other · North Sea	0	31	1	31	0.0× / 1.4
Wrecks · North Sea	0	31	1	249	0.0× / 1
Debris · Persian Gulf	0	31	1	46	— / 0
Wrecks · Red Sea	0	31	1	169	— / 0
Structures · South China Sea	0	31	1	188	0.0× / 0.2
Restricted · South Pacific Ocean	0	31	1	67	— / 0
Nav aids · The Coastal Waters of Southeast Alaska and British Columbia	0	28.5	0	—	0.0× / 1.6
Nav aids · Malacca Strait	0	21.6	0	—	0.0× / 0.2

Cite: seahazards.com Sea Ledger, 2020-05, 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.