Sea Ledger, October 2017

2017-10-01 to 2017-10-31 · archive

issued: 782
warning-days in force: 14,888
in force at month end: 453
sea × type cells: 268

baseline: same month, previous 5 years (2016-10, 2015-10, 2014-10, 2013-10, 2012-10)

By type

type	issued	warning-days	in force at end
Incidents	137	1,269.3	45
Exercises	132	1,161.5	25
Surveys	114	3,106.5	89
Icebergs	91	111.2	4
Nav aids	87	4,379.1	141
Missiles	56	426.6	8
Quakes	32	85.8	9
Spills	23	335	6
Derelicts	22	156.9	4
Debris	21	57.7	1
Cable ops	13	303.7	7
Storms	12	124.9	3
Wrecks	11	2,155.5	73
Other	10	610.6	20
Piracy	10	81	2
Containers	6	17.9	1
Restricted	3	185.8	5
Ordnance	2	133.1	4
Volcanic	0	155	5
Structures	0	31	1

By sea and type · 200 cells, most issued first

cell	issued	warning-days	at end	longest d	vs 5 y
Surveys · South Atlantic Oceansurge	36	212.5	8	195	4.4× / 8.2
Icebergs · South Atlantic Oceansurge	33	37	1	31	3.3× / 10
Incidents · South China Sea	30	233.9	17	71	1.3× / 22.8
Icebergs · Labrador Sea	30	39.6	1	32	1.1× / 27.8
Icebergs · Southern Oceannew	23	22.4	1	29	new / 0
Exercises · South Atlantic Oceansurge	20	121.3	1	49	2.4× / 8.4
Incidents · Mediterranean Sea - Eastern Basin	18	266.5	6	45	1.3× / 13.4
Exercises · North Pacific Ocean	18	144.2	2	44	1.2× / 14.8
Spills · Gulf of Mexicosurge	16	223	5	43	4.0× / 4
Exercises · Black Sea	16	120.1	4	36	1.8× / 9
Nav aids · North Sea	14	180.4	7	118	1.3× / 11.2
Incidents · North Pacific Ocean	14	124.3	4	67	0.5× / 25.8
Exercises · North Atlantic Oceansurge	14	112.8	3	61	3.0× / 4.6
Surveys · Aegean Seasurge	14	16.7	0	—	35× / 0.4
Incidents · North Atlantic Ocean	13	134.7	5	41	1.0× / 13.4
Missiles · Barentsz Seasurge	13	86.2	3	32	3.0× / 4.4
Surveys · Mediterranean Sea - Eastern Basinsurge	12	142.7	6	116	10× / 1.2
Incidents · South Pacific Ocean	12	17	0	—	1.4× / 8.4
Missiles · North Pacific Ocean	11	91.8	1	60	1.1× / 10
Missiles · Black Seasurge	11	79.9	0	—	5.0× / 2.2
Incidents · Philippine Seasurge	11	48.8	1	38	2.3× / 4.8
Nav aids · Gulf of Mexicosurge	10	339.8	10	270	3.3× / 3
Exercises · Bay of Bengal	10	88.8	5	53	1.5× / 6.6
Exercises · Aegean Seasurge	9	252.6	8	306	2.5× / 3.6
Nav aids · North Pacific Oceansurgelong running	9	227	9	377	3.5× / 2.6
Missiles · North Atlantic Oceansurge	9	63.8	0	—	2.0× / 4.4
Storms · Gulf of Mexiconew	8	31.9	0	—	new / 0
Exercises · Mediterranean Sea - Eastern Basin	8	25.5	0	—	1.3× / 6
Incidents · Caribbean Sea	7	148.6	3	44	1.6× / 4.4
Surveys · Caribbean Seasurge	7	130.7	3	292	8.8× / 0.8
Exercises · Philippine Sea	7	68.6	0	—	1.1× / 6.2
Quakes · Banda Seasurge	7	15.6	5	7	18× / 0.4
Quakes · South Pacific Ocean	7	14.7	3	23	0.8× / 9
Nav aids · North Atlantic Oceanlong running	6	465.5	15	1,623	0.9× / 7
Piracy · Gulf of Guineasurge	6	44.8	2	32	15× / 0.4
Nav aids · Irish Sea and St. George's Channelsurge	6	13.9	0	—	2.3× / 2.6
Surveys · North Atlantic Oceansurgelong running	5	268.1	9	621	3.6× / 1.4
Surveys · South China Seasurge	5	121.3	5	90	25× / 0.2
Surveys · Arabian Seasurge	5	84.7	2	40	6.3× / 0.8
Incidents · South Atlantic Ocean	5	41.6	1	41	0.7× / 7.2
Nav aids · Celtic Seasurge	5	33.5	0	—	2.8× / 1.8
Incidents · Coral Sea	5	9.3	0	—	1.4× / 3.6
Surveys · Black Seasurge	4	152.8	4	90	2.2× / 1.8
Nav aids · Coral Sealong running	4	125.9	4	1,292	1.7× / 2.4
Storms · Caribbean Seasurge	4	93	3	49	6.7× / 0.6
Nav aids · Great Australian Bightsurgelong running	4	48.4	2	699	2.0× / 2
Nav aids · English Channel	4	47.6	1	35	1.3× / 3.2
Incidents · Gulf of Thailandsurge	4	45.2	2	34	20× / 0.2
Derelicts · North Atlantic Ocean	4	24.1	0	—	0.9× / 4.2
Exercises · Baltic Sea	4	14.5	0	—	1.3× / 3
Derelicts · Mediterranean Sea - Eastern Basinsurge	4	12	0	—	20× / 0.2
Quakes · South Atlantic Oceansurge	4	12	0	—	4.0× / 1
Nav aids · Caribbean Sealong running	3	772.1	25	495	1.0× / 3
Surveys · Kara Seanew	3	208.9	3	106	new / 0
Nav aids · Inner Seas off the West Coast of Scotland	3	191.9	5	160	0.7× / 4.4
Surveys · Bay of Bengallong running	3	99	4	480	1.7× / 1.8
Surveys · Indian Ocean	3	84	4	341	1.7× / 1.8
Nav aids · Indian Oceanlong running	3	63.2	3	842	0.9× / 3.2
Exercises · Arabian Sea	3	58.5	1	34	0.4× / 7.8
Spills · North Pacific Oceansurge	3	49	1	40	2.5× / 1.2
Surveys · Hudson Straitsurge	3	47.7	2	25	7.5× / 0.4
Cable ops · North Atlantic Ocean	3	30.3	1	27	0.6× / 4.8
Exercises · Yellow Sea	3	20.8	0	—	0.2× / 12.4
Other · Davis Straitsurge	3	19.1	0	—	7.5× / 0.4
Missiles · Sea of Okhotsksurge	3	19.1	0	—	2.1× / 1.4
Exercises · South Pacific Ocean	3	14.5	0	—	0.6× / 5
Exercises · South China Sea	3	14.2	0	—	0.5× / 6
Quakes · Arctic Oceannew	3	9	0	—	new / 0
Derelicts · Hudson Baynew	3	9	0	—	new / 0
Derelicts · Indian Ocean	3	9	0	—	0.9× / 3.2
Debris · North Pacific Oceansurge	3	9	0	—	5.0× / 0.6
Quakes · North Pacific Ocean	3	9	0	—	0.5× / 5.6
Debris · Arafura Seasurge	3	6.9	0	—	7.5× / 0.4
Debris · Celtic Seanew	3	6.8	1	6	new / 0
Nav aids · South Atlantic Ocean	2	477.7	14	188	0.2× / 9.2
Wrecks · Caribbean Sealong running	2	352.1	12	472	10× / 0.2
Nav aids · Arabian Seanew	2	153.4	5	187	new / 0
Surveys · North Sea	2	114.1	2	37	3.3× / 0.6
Nav aids · Mediterranean Sea - Eastern Basinlong running	2	59.3	2	568	5.0× / 0.4
Cable ops · Davis Straitnew	2	55.6	0	—	new / 0
Incidents · Indian Ocean	2	46.3	2	117	0.3× / 8
Wrecks · English Channel	2	39.3	3	33	10× / 0.2
Nav aids · Gulf of California	2	38.6	3	230	10× / 0.2
Exercises · Laccadive Sea	2	38.3	1	33	1.3× / 1.6
Surveys · Gulf of Mexico	2	35.6	1	30	3.3× / 0.6
Nav aids · The Coastal Waters of Southeast Alaska and British Columbia	2	33	2	37	10× / 0.2
Cable ops · South Pacific Oceannew	2	31.9	2	85	new / 0
Derelicts · South Pacific Ocean	2	31.1	2	33	1.3× / 1.6
Spills · North Atlantic Ocean	2	30	0	—	0.8× / 2.4
Exercises · Barentsz Sea	2	22.2	0	—	1.1× / 1.8
Incidents · Gulf of Mexico	2	20.4	1	41	0.7× / 2.8
Surveys · Java Seanew	2	19.3	1	19	new / 0
Piracy · Arabian Seanew	2	18.6	0	—	new / 0
Missiles · Kara Sea	2	17.9	1	15	1.7× / 1.2
Incidents · Eastern China Sea	2	15.1	0	—	10× / 0.2
Missiles · Aegean Sea	2	12.1	1	303	3.3× / 0.6
Incidents · Tyrrhenian Sea	2	11.7	1	11	3.3× / 0.6
Incidents · Bismarck Sea	2	8.1	0	—	1.7× / 1.2
Debris · Indian Ocean	2	6	0	—	10× / 0.2
Icebergs · Kara Sea	2	6	0	—	5.0× / 0.4
Debris · North Atlantic Ocean	2	6	0	—	2.5× / 0.8
Quakes · North Atlantic Ocean	2	6	0	—	2.0× / 1
Debris · South Atlantic Oceannew	2	6	0	—	new / 0
Containers · South China Sea	2	6	0	—	5.0× / 0.4
Debris · South China Seanew	2	6	0	—	new / 0
Containers · South Pacific Oceannew	2	6	0	—	new / 0
Debris · South Pacific Oceannew	2	6	0	—	new / 0
Derelicts · North Pacific Ocean	2	5.8	1	6	0.7× / 2.8
Restricted · Sea of Azov	2	3.6	0	—	10× / 0.2
Incidents · Java Sea	2	1.5	0	—	10× / 0.2
Exercises · North Sea	2	0.9	0	—	10× / 0.2
Wrecks · South China Sealong running	1	503.5	17	1,268	0.7× / 1.4
Nav aids · South Pacific Oceanlong running	1	342.5	11	421	0.6× / 1.6
Wrecks · North Sea	1	186	6	216	2.5× / 0.4
Surveys · Beaufort Sealong running	1	162.6	5	1,858	0.7× / 1.4
Other · Coral Sealong running	1	124.1	4	930	5.0× / 0.2
Surveys · Barentsz Sea	1	107.9	2	105	1.7× / 0.6
Wrecks · South Atlantic Ocean	1	86.3	2	263	1.7× / 0.6
Wrecks · South Pacific Ocean	1	79	3	36	5.0× / 0.2
Surveys · Sea of Okhotsk	1	70.4	1	330	new / 0
Other · South China Sealong running	1	62.1	2	1,070	0.6× / 1.8
Ordnance · North Sea	1	62	2	48	1.7× / 0.6
Cable ops · Caribbean Sea	1	45.5	1	319	0.8× / 1.2
Nav aids · Laccadive Sea	1	44.2	1	39	1.7× / 0.6
Ordnance · Black Sealong running	1	40.1	1	503	new / 0
Nav aids · Bristol Channel	1	39.1	2	166	5.0× / 0.2
Restricted · Black Sealong running	1	38.7	1	1,609	1.7× / 0.6
Derelicts · South China Sea	1	34	1	284	0.7× / 1.4
Other · Indian Ocean	1	31.2	1	186	1.3× / 0.8
Nav aids · Arafura Sealong running	1	31.1	1	495	2.5× / 0.4
Nav aids · Bass Straitlong running	1	31.1	1	913	1.3× / 0.8
Cable ops · Black Sea	1	31	1	95	1.0× / 1
Other · Gulf of Mexico	1	31	1	33	1.0× / 1
Wrecks · Sea of Okhotsk	1	31	1	76	new / 0
Surveys · North Pacific Ocean	1	29.7	0	—	1.7× / 0.6
Surveys · Gulf of Guinea	1	27.4	1	27	5.0× / 0.2
Incidents · Ionian Sea	1	26.5	0	—	1.3× / 0.8
Other · North Pacific Ocean	1	22.9	1	22	5.0× / 0.2
Surveys · Mozambique Channel	1	21.6	1	21	2.5× / 0.4
Nav aids · Bay of Biscay	1	20.4	0	—	new / 0
Derelicts · Japan Sea	1	20.3	0	—	new / 0
Cable ops · Beaufort Sea	1	19	0	—	5.0× / 0.2
Spills · Caribbean Sea	1	19	0	—	5.0× / 0.2
Incidents · Mediterranean Sea - Western Basin	1	18.1	0	—	0.8× / 1.2
Incidents · Persian Gulf	1	16	0	—	new / 0
Exercises · Mediterranean Sea - Western Basin	1	15.7	0	—	new / 0
Missiles · Arctic Ocean	1	14.4	0	—	1.0× / 1
Spills · Bering Sea	1	14	0	—	2.5× / 0.4
Wrecks · Celtic Sea	1	13.2	1	13	5.0× / 0.2
Missiles · Laccadive Sea	1	9.9	1	32	1.0× / 1
Incidents · Arabian Sea	1	9.5	1	9	0.4× / 2.4
Piracy · Gulf of Aden	1	9.5	0	—	2.5× / 0.4
Surveys · Great Australian Bight	1	7.8	0	—	new / 0
Incidents · Mozambique Channel	1	7.8	1	39	0.7× / 1.4
Cable ops · Eastern China Sea	1	7	0	—	1.7× / 0.6
Piracy · Singapore Strait	1	7	0	—	new / 0
Missiles · South Atlantic Ocean	1	6.9	1	6	0.8× / 1.2
Wrecks · Mediterranean Sea - Eastern Basin	1	6.6	1	6	new / 0
Missiles · South Pacific Ocean	1	6.6	0	—	0.4× / 2.6
Cable ops · Sea of Marmara	1	6.5	1	6	new / 0
Quakes · Philippine Sea	1	6.4	0	—	0.4× / 2.4
Other · English Channel	1	6.2	1	6	1.7× / 0.6
Exercises · Andaman or Burma Sea	1	5.1	0	—	5.0× / 0.2
Missiles · Baffin Bay	1	5	0	—	new / 0
Cable ops · South Atlantic Ocean	1	4.6	1	4	0.1× / 20.8
Surveys · Persian Gulf	1	4.3	0	—	1.3× / 0.8
Exercises · Celebes Sea	1	3.5	0	—	5.0× / 0.2
Exercises · Norwegian Sea	1	3.4	0	—	new / 0
Exercises · Gulf of Thailand	1	3.1	0	—	new / 0
Debris · Barentsz Sea	1	3	0	—	5.0× / 0.2
Derelicts · Bay of Bengal	1	3	0	—	new / 0
Quakes · Bering Sea	1	3	0	—	5.0× / 0.2
Quakes · Bismarck Sea	1	3	0	—	2.5× / 0.4
Quakes · Gulf of Tomini	1	3	0	—	5.0× / 0.2
Derelicts · Laccadive Sea	1	3	0	—	1.3× / 0.8
Icebergs · Laptev Sea	1	3	0	—	1.3× / 0.8
Containers · North Atlantic Ocean	1	3	0	—	1.3× / 0.8
Icebergs · North Atlantic Ocean	1	3	0	—	5.0× / 0.2
Quakes · Southern Ocean	1	3	0	—	0.8× / 1.2
Containers · North Sea	1	2.9	1	2	new / 0
Exercises · Coral Sea	1	2.4	0	—	0.3× / 3
Debris · Timor Sea	1	2	0	—	1.3× / 0.8
Exercises · Gulf of Mexico	1	1.3	0	—	0.6× / 1.8
Other · Japan Sea	1	1.3	0	—	new / 0
Quakes · Savu Sea	1	1.1	1	1	new / 0
Exercises · Celtic Sea	1	1	0	—	new / 0
Icebergs · Davis Strait	1	0.2	1	0	5.0× / 0.2
Incidents · Davis Strait	1	0.1	0	—	0.4× / 2.6
Surveys · Arctic Oceanlong running	0	201.6	6	1,197	0.0× / 2.2
Wrecks · Arabian Sealong running	0	186	6	376	0.0× / 1
Surveys · The Northwestern Passageslong running	0	167.7	5	1,912	— / 0
Other · Caribbean Sea	0	124	4	284	0.0× / 1
Surveys · Bering Sea	0	93	3	112	— / 0
Wrecks · North Pacific Ocean	0	93	3	363	— / 0
Volcanic · Philippine Sealong running	0	93	3	2,011	— / 0
Nav aids · Tasman Sealong running	0	93	3	518	0.0× / 0.4
Nav aids · Bay of Bengal	0	62	2	200	0.0× / 0.8
Nav aids · Davis Strait	0	62	2	138	0.0× / 0.6
Wrecks · Gulf of Mexico	0	62	2	229	0.0× / 0.2
Other · Hudson Bay	0	62	2	106	— / 0

Cite: seahazards.com Sea Ledger, 2017-10, 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.