Sea Ledger, November 2017

2017-11-01 to 2017-11-30 · archive

issued: 748
warning-days in force: 14,276
in force at month end: 481
sea × type cells: 263

baseline: same month, previous 5 years (2016-11, 2015-11, 2014-11, 2013-11, 2012-11)

By type

type	issued	warning-days	in force at end
Incidents	166	1,645.8	69
Exercises	132	965.5	37
Surveys	85	2,682.4	80
Icebergs	85	94.3	4
Nav aids	69	4,364.2	146
Quakes	49	178	8
Missiles	39	213.3	6
Derelicts	29	144.7	4
Cable ops	22	286.5	6
Wrecks	15	2,261.3	74
Piracy	13	79.7	2
Debris	12	27.6	1
Spills	11	149	5
Other	10	644.9	21
Containers	4	9.9	0
Ordnance	3	127.4	4
Storms	2	90	3
Restricted	1	131.8	4
Mines	1	0.1	1
Volcanic	0	150	5
Structures	0	30	1

By sea and type · 200 cells, most issued first

cell	issued	warning-days	at end	longest d	vs 5 y
Incidents · South China Seasurge	46	431.1	13	101	2.6× / 18
Icebergs · South Atlantic Oceansurge	30	32	1	30	3.6× / 8.4
Icebergs · Labrador Seasurge	26	29.7	2	31	2.0× / 13
Icebergs · Southern Oceansurge	24	24	1	30	40× / 0.6
Quakes · South Pacific Oceansurge	23	74.1	1	30	2.0× / 11.2
Incidents · Mediterranean Sea - Eastern Basin	20	260.3	10	47	1.6× / 12.2
Incidents · North Pacific Ocean	20	186	10	97	0.6× / 32
Exercises · Aegean Seasurge	17	259.2	9	336	4.3× / 4
Exercises · South Atlantic Ocean	17	85.4	2	33	1.2× / 14
Surveys · South Atlantic Oceansurge	16	265.1	8	225	2.6× / 6.2
Incidents · North Atlantic Ocean	15	132	7	47	0.9× / 17
Exercises · North Pacific Ocean	14	88.2	4	66	0.8× / 16.4
Exercises · Bay of Bengal	14	87.4	4	35	1.3× / 10.6
Surveys · North Atlantic Oceansurgelong running	10	330.4	12	651	4.2× / 2.4
Nav aids · North Pacific Oceansurge	9	279	8	300	3.0× / 3
Exercises · Mediterranean Sea - Eastern Basin	9	28.8	0	—	1.4× / 6.4
Exercises · Arabian Sea	8	65.3	2	33	1.1× / 7.6
Piracy · Gulf of Guineasurge	8	54	1	36	4.4× / 1.8
Missiles · North Atlantic Oceansurge	8	30.8	1	27	2.0× / 4
Missiles · South Pacific Oceansurge	8	26.8	0	—	6.7× / 1.2
Exercises · South Pacific Oceansurge	8	23.2	1	18	2.4× / 3.4
Exercises · Philippine Seasurge	8	20.9	0	—	3.1× / 2.6
Surveys · Mediterranean Sea - Eastern Basinsurge	7	148.5	3	136	3.2× / 2.2
Exercises · Black Sea	7	107.8	3	36	1.2× / 5.8
Missiles · North Pacific Ocean	7	58.9	2	90	1.3× / 5.6
Missiles · Barentsz Sea	7	51.5	1	35	1.8× / 3.8
Nav aids · English Channel	7	45.2	1	36	1.9× / 3.6
Incidents · South Atlantic Ocean	7	45.1	2	39	1.2× / 6
Nav aids · North Sea	6	189.1	7	148	0.4× / 16.4
Surveys · Bay of Bengalsurgelong running	6	143.9	4	510	7.5× / 0.8
Spills · Gulf of Mexicosurge	6	84	4	42	2.0× / 3
Exercises · North Atlantic Ocean	6	77.3	4	91	1.2× / 5
Surveys · Arabian Seasurge	6	71.8	5	45	2.5× / 2.4
Incidents · Philippine Sea	6	24.6	3	45	1.6× / 3.8
Incidents · South Pacific Ocean	6	24.3	2	13	0.8× / 8
Derelicts · North Pacific Oceansurge	6	17.8	0	—	2.3× / 2.6
Quakes · Coral Seasurge	6	12.1	0	—	15× / 0.4
Nav aids · South Atlantic Ocean	5	457.7	15	194	0.6× / 8.4
Surveys · Indian Oceansurgelong running	5	102.1	1	371	5.0× / 1
Surveys · Barentsz Seanew	5	82.4	2	84	new / 0
Incidents · Gulf of Mexico	5	68.2	4	32	1.3× / 3.8
Exercises · Laccadive Sea	5	45.3	2	31	1.9× / 2.6
Exercises · Yellow Sea	5	24.9	1	27	0.5× / 11.2
Quakes · North Pacific Ocean	5	15	0	—	0.7× / 7.4
Debris · Timor Seasurge	5	13	0	—	3.1× / 1.6
Nav aids · Inner Seas off the West Coast of Scotland	4	131.6	4	190	1.2× / 3.4
Incidents · Gulf of Thailandsurge	4	90.5	3	39	2.2× / 1.8
Incidents · Caribbean Sea	4	80.1	2	43	0.7× / 6.2
Incidents · Eastern China Seasurge	4	58.2	2	21	10× / 0.4
Spills · North Pacific Oceansurge	4	51	1	37	5.0× / 0.8
Surveys · North Seasurge	4	44.6	0	—	3.3× / 1.2
Derelicts · Arafura Seanew	4	12	0	—	new / 0
Missiles · Indian Oceansurge	4	11.5	0	—	2.9× / 1.4
Quakes · South Atlantic Oceansurge	4	8.6	2	19	3.3× / 1.2
Incidents · Ionian Seasurge	4	8.3	2	4	10× / 0.4
Icebergs · Davis Strait	4	5.6	0	—	0.6× / 6.8
Debris · North Atlantic Oceansurge	4	3.4	1	3	2.2× / 1.8
Incidents · Coral Sea	4	0.7	0	—	1.3× / 3
Wrecks · South China Seasurgelong running	3	537.5	18	1,298	7.5× / 0.4
Nav aids · North Atlantic Oceanlong running	3	511.7	18	1,653	0.6× / 5
Nav aids · Coral Sealong running	3	123.5	4	1,322	0.9× / 3.2
Ordnance · North Seasurge	3	67.4	2	61	5.0× / 0.6
Nav aids · Davis Straitnew	3	60.7	2	168	new / 0
Nav aids · South China Seasurge	3	57.6	3	179	7.5× / 0.4
Incidents · Java Seasurge	3	31.9	1	20	3.0× / 1
Cable ops · South Pacific Oceansurge	3	30.8	0	—	15× / 0.2
Surveys · Andaman or Burma Seasurge	3	20.3	1	27	7.5× / 0.4
Nav aids · The Coastal Waters of Southeast Alaska and British Columbia	3	18.5	2	67	1.9× / 1.6
Cable ops · Philippine Seasurge	3	18.3	1	28	3.8× / 0.8
Exercises · Baltic Sea	3	13.6	0	—	1.1× / 2.8
Exercises · Coral Sea	3	11.5	2	26	0.9× / 3.2
Cable ops · North Sea	3	10.7	0	—	1.9× / 1.6
Derelicts · Indian Ocean	3	9	0	—	1.1× / 2.6
Incidents · Arafura Seasurge	3	0.8	0	—	2.1× / 1.4
Nav aids · Caribbean Sealong running	2	752.6	24	525	10× / 0.2
Wrecks · Caribbean Sea	2	360	12	318	10× / 0.2
Nav aids · Gulf of Mexico	2	288.9	9	300	0.5× / 3.8
Nav aids · South Pacific Oceanlong running	2	288.9	9	451	2.0× / 1
Wrecks · North Sea	2	173.7	5	246	5.0× / 0.4
Surveys · South China Seanew	2	141.3	3	107	new / 0
Surveys · Caribbean Sea	2	101.9	2	322	3.3× / 0.6
Surveys · Black Sea	2	92.9	3	83	10× / 0.2
Nav aids · Bay of Bengal	2	88.5	3	230	3.3× / 0.6
Wrecks · North Atlantic Ocean	2	74.9	3	304	10× / 0.2
Wrecks · Irish Sea and St. George's Channel	2	60	2	325	10× / 0.2
Nav aids · Andaman or Burma Seanew	2	51	2	28	new / 0
Surveys · Sea of Okhotsknew	2	45.1	0	—	new / 0
Incidents · Indian Ocean	2	43.9	1	147	0.4× / 5
Derelicts · South Pacific Ocean	2	35.9	1	30	1.0× / 2
Cable ops · Celtic Seanew	2	28.7	0	—	new / 0
Surveys · South Pacific Ocean	2	25.2	1	25	10× / 0.2
Storms · North Atlantic Oceannew	2	23.9	1	23	new / 0
Incidents · Persian Gulfnew	2	23.9	1	21	new / 0
Incidents · Davis Strait	2	15.6	0	—	2.5× / 0.8
Exercises · South China Sea	2	12	1	18	0.5× / 4.2
Cable ops · Eastern China Sea	2	11.8	0	—	2.0× / 1
Piracy · Indian Ocean	2	8.9	0	—	2.5× / 0.8
Missiles · Black Sea	2	8.3	2	4	0.6× / 3.4
Surveys · Tasman Sea	2	7.6	2	85	5.0× / 0.4
Derelicts · Arabian Sea	2	6	0	—	10× / 0.2
Derelicts · Bay of Bengal	2	6	0	—	2.0× / 1
Derelicts · Coral Sea	2	6	0	—	3.3× / 0.6
Quakes · Philippine Sea	2	6	0	—	1.7× / 1.2
Derelicts · Caribbean Sea	2	5.5	1	13	1.7× / 1.2
Derelicts · South Atlantic Ocean	2	4.5	1	4	1.7× / 1.2
Quakes · Bismarck Sea	2	3.8	1	23	2.0× / 1
Nav aids · Bay of Biscaynew	2	3.7	0	—	new / 0
Nav aids · Gulf of Alaska	2	0.5	0	—	1.4× / 1.4
Wrecks · Arabian Sealong running	1	190.2	7	406	new / 0
Other · Caribbean Sea	1	123.1	5	314	2.5× / 0.4
Nav aids · Tasman Sealong running	1	105.7	4	548	1.0× / 1
Wrecks · English Channel	1	90	3	63	1.7× / 0.6
Wrecks · North Pacific Oceanlong running	1	89.2	3	393	5.0× / 0.2
Wrecks · Gulf of Mexico	1	83.6	3	259	5.0× / 0.2
Other · South China Sealong running	1	72	3	1,100	1.0× / 1
Nav aids · Bristol Channel	1	60.7	2	196	new / 0
Nav aids · Great Australian Bightlong running	1	60.3	2	729	1.7× / 0.6
Other · North Atlantic Ocean	1	47.1	2	143	0.5× / 2.2
Cable ops · South Atlantic Ocean	1	47	1	34	0.1× / 21.8
Quakes · Banda Sea	1	41	2	37	1.0× / 1
Surveys · Celtic Sea	1	34.2	1	163	0.2× / 4.2
Surveys · Gulf of Guinea	1	33.3	2	57	new / 0
Other · North Sea	1	33.3	1	193	0.8× / 1.2
Other · Gulf of Mexico	1	32.9	0	—	1.3× / 0.8
Cable ops · Caribbean Sea	1	31.6	1	349	1.7× / 0.6
Nav aids · Arafura Sealong running	1	30.5	1	525	5.0× / 0.2
Surveys · Sea of Marmara	1	30.3	2	84	new / 0
Other · Indian Ocean	1	30.2	1	216	2.5× / 0.4
Nav aids · Bass Straitlong running	1	30	2	943	0.8× / 1.2
Surveys · Java Sea	1	30	1	41	new / 0
Nav aids · Mozambique Channel	1	27.2	1	27	2.5× / 0.4
Incidents · Arabian Sea	1	25.4	1	39	0.5× / 2
Other · Hudson Strait	1	25.4	1	25	5.0× / 0.2
Surveys · Gulf of Thailand	1	25	0	—	new / 0
Other · South Pacific Ocean	1	25	0	—	new / 0
Incidents · Tyrrhenian Sea	1	22.6	0	—	0.8× / 1.2
Surveys · Gulf of Mexico	1	22.3	1	51	5.0× / 0.2
Surveys · North Pacific Ocean	1	19.9	0	—	0.8× / 1.2
Incidents · Laccadive Sea	1	19.2	0	—	0.7× / 1.4
Surveys · Laccadive Sea	1	17.4	1	17	5.0× / 0.2
Incidents · Tasman Sea	1	17	1	16	1.3× / 0.8
Incidents · Mozambique Channel	1	16.9	0	—	1.0× / 1
Spills · North Atlantic Ocean	1	14	0	—	0.5× / 2
Cable ops · North Pacific Ocean	1	13	0	—	1.3× / 0.8
Missiles · Aegean Sea	1	11.6	0	—	0.8× / 1.2
Cable ops · Mediterranean Sea - Western Basin	1	11.5	1	11	new / 0
Cable ops · North Atlantic Ocean	1	11.4	1	35	0.2× / 4.4
Cable ops · Arabian Sea	1	11.2	0	—	1.0× / 1
Incidents · Japan Sea	1	11	1	10	1.7× / 0.6
Cable ops · Mediterranean Sea - Eastern Basin	1	9.9	0	—	0.7× / 1.4
Restricted · Mediterranean Sea - Eastern Basin	1	9.1	0	—	5.0× / 0.2
Cable ops · English Channel	1	7.6	0	—	5.0× / 0.2
Incidents · Mediterranean Sea - Western Basin	1	7.3	1	7	5.0× / 0.2
Piracy · Gulf of Aden	1	7	0	—	new / 0
Piracy · Gulf of Oman	1	7	0	—	new / 0
Other · Tasman Sea	1	6.9	1	6	new / 0
Missiles · Greenland Sea	1	5.7	0	—	5.0× / 0.2
Cable ops · South China Sea	1	5.6	0	—	0.5× / 2.2
Missiles · Laccadive Sea	1	5.2	0	—	0.8× / 1.2
Exercises · Barentsz Sea	1	4.8	1	4	2.5× / 0.4
Surveys · Persian Gulf	1	3.6	1	3	new / 0
Debris · Arafura Sea	1	3	0	—	5.0× / 0.2
Quakes · Caribbean Sea	1	3	0	—	5.0× / 0.2
Containers · Coral Sea	1	3	0	—	5.0× / 0.2
Quakes · Indian Ocean	1	3	0	—	0.4× / 2.8
Exercises · Indian Ocean	1	3	1	3	0.4× / 2.6
Debris · Irish Sea and St. George's Channel	1	3	0	—	new / 0
Derelicts · Japan Sea	1	3	0	—	5.0× / 0.2
Quakes · Japan Sea	1	3	0	—	5.0× / 0.2
Derelicts · Kara Sea	1	3	0	—	5.0× / 0.2
Derelicts · Laccadive Sea	1	3	0	—	5.0× / 0.2
Containers · Mediterranean Sea - Western Basin	1	3	0	—	new / 0
Quakes · Molukka Sea	1	3	0	—	0.5× / 2.2
Containers · North Atlantic Ocean	1	3	0	—	5.0× / 0.2
Derelicts · North Atlantic Ocean	1	3	0	—	0.2× / 4.4
Debris · North Pacific Ocean	1	3	0	—	new / 0
Icebergs · South Pacific Ocean	1	3	0	—	new / 0
Other · South Atlantic Ocean	1	2.8	0	—	0.5× / 2
Piracy · South China Sea	1	2.8	1	2	2.5× / 0.4
Exercises · Celtic Sea	1	2.5	0	—	2.5× / 0.4
Quakes · Norwegian Sea	1	2.4	1	2	new / 0
Surveys · Aegean Sea	1	2.3	0	—	new / 0
Exercises · Adriatic Sea	1	2.2	0	—	2.5× / 0.4
Exercises · Andaman or Burma Sea	1	1.9	0	—	new / 0
Nav aids · Celtic Sea	1	1.8	0	—	0.6× / 1.8
Surveys · Great Australian Bight	1	1.6	0	—	new / 0
Nav aids · Mediterranean Sea - Western Basin	1	1.1	0	—	0.8× / 1.2
Quakes · Sea of Okhotsk	1	1.1	1	1	new / 0
Containers · South Pacific Ocean	1	0.8	0	—	new / 0
Incidents · Timor Sea	1	0.7	1	0	1.3× / 0.8
Exercises · Mediterranean Sea - Western Basin	1	0.3	0	—	new / 0
Nav aids · Irish Sea and St. George's Channel	1	0.2	0	—	0.3× / 3.8
Incidents · Malacca Strait	1	0.2	1	0	new / 0
Mines · English Channel	1	0.1	1	0	5.0× / 0.2
Surveys · Arctic Oceanlong running	0	180	6	1,227	— / 0
Nav aids · Arabian Sea	0	150	5	217	0.0× / 1.2
Surveys · Beaufort Sealong running	0	150	5	1,888	— / 0
Surveys · The Northwestern Passageslong running	0	150	5	1,942	— / 0
Other · Coral Sealong running	0	120	4	960	0.0× / 0.6
Surveys · Bering Sea	0	90	3	142	— / 0

Cite: seahazards.com Sea Ledger, 2017-11, 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.