Sea Ledger, October 2011

2011-10-01 to 2011-10-31 · archive

issued: 428
warning-days in force: 6,496
in force at month end: 203
sea × type cells: 205

baseline: same month, previous 5 years (2010-10, 2009-10, 2008-10, 2007-10, 2006-10)

By type

type	issued	warning-days	in force at end
Incidents	84	683.7	19
Exercises	79	826.9	23
Nav aids	61	1,261.8	45
Cable ops	53	1,048.1	32
Quakes	29	76.6	5
Piracy	25	157.6	5
Missiles	21	166.6	5
Derelicts	20	62.9	2
Surveys	17	866.6	30
Other	8	394.7	10
Containers	8	31.9	1
Wrecks	7	528.1	16
Restricted	4	146.2	4
Icebergs	4	12.7	0
Spills	3	56	0
Debris	2	5.6	1
Volcanic	1	19.1	0
Towing	1	18.8	0
Ordnance	1	38.2	2
War risk	0	62.8	2
Structures	0	31	1

By sea and type · 200 cells, most issued first

cell	issued	warning-days	at end	longest d	vs 5 y
Incidents · North Pacific Oceansurge	25	172.5	4	59	2.2× / 11.2
Exercises · North Pacific Oceansurge	20	72.7	2	35	2.4× / 8.2
Cable ops · South Atlantic Oceanlong running	16	153.8	6	1,087	0.9× / 18
Quakes · South Pacific Ocean	15	39.5	2	33	1.3× / 11.8
Nav aids · North Atlantic Oceansurgelong running	12	76.4	4	517	3.2× / 3.8
Piracy · Indian Oceansurge	12	62.2	2	29	2.1× / 5.6
Nav aids · North Sea	12	59.2	2	36	1.3× / 9.2
Incidents · Coral Seasurge	10	14	0	—	3.3× / 3
Exercises · South Atlantic Ocean	9	148.8	2	49	0.9× / 10.4
Exercises · Bay of Bengal	9	63.1	3	42	1.2× / 7.4
Incidents · North Atlantic Ocean	9	45.6	4	46	1.6× / 5.6
Exercises · Arabian Seasurge	8	75	4	34	2.4× / 3.4
Cable ops · North Atlantic Ocean	7	87	2	34	1.9× / 3.6
Cable ops · Gulf of Guineasurge	7	33.1	2	30	7.0× / 1
Exercises · Yellow Sea	6	55.2	1	32	1.1× / 5.6
Missiles · North Pacific Ocean	6	52.4	2	59	1.0× / 6.2
Piracy · Arabian Seasurge	6	45.5	0	—	3.0× / 2
Cable ops · Black Seasurge	6	37.2	3	35	15× / 0.4
Nav aids · Gulf of Alaskasurge	6	6.2	0	—	2.1× / 2.8
Exercises · South China Sea	5	99.8	3	33	1.2× / 4.2
Incidents · South China Sea	5	18.1	1	37	1.4× / 3.6
Derelicts · North Atlantic Oceansurge	5	14.7	1	33	5.0× / 1
Surveys · South Atlantic Ocean	4	54.8	3	122	0.9× / 4.2
Exercises · Philippine Sea	4	53.7	2	33	1.4× / 2.8
Incidents · Philippine Sea	4	39.7	0	—	0.8× / 5.2
Wrecks · South Pacific Oceannew	4	38.1	1	241	new / 0
Incidents · South Pacific Ocean	4	34.6	1	73	0.4× / 10.4
Exercises · Laccadive Sea	4	33.7	1	31	0.7× / 6
Containers · South Pacific Oceannew	4	19.9	1	19	new / 0
Incidents · Indian Oceansurge	4	9.3	0	—	2.0× / 2
Nav aids · South Atlantic Oceanlong running	3	312.8	11	1,167	0.6× / 5.4
Nav aids · South Pacific Oceansurge	3	92.2	4	81	3.0× / 1
Nav aids · Arabian Seasurgelong running	3	73.7	2	451	15× / 0.2
Nav aids · North Pacific Ocean	3	69.7	3	308	1.5× / 2
Incidents · South Atlantic Ocean	3	66.5	2	56	0.6× / 4.8
Nav aids · English Channel	3	35.1	1	30	1.1× / 2.8
Cable ops · North Seasurge	3	25.7	0	—	2.1× / 1.4
Derelicts · North Pacific Ocean	3	15.4	0	—	1.9× / 1.6
Missiles · North Atlantic Oceansurge	3	15.2	0	—	15× / 0.2
Exercises · South Pacific Ocean	3	12.6	0	—	0.9× / 3.2
Quakes · North Pacific Ocean	3	9	0	—	0.5× / 6
Nav aids · Indian Oceansurge	3	8.8	1	24	15× / 0.2
Piracy · Gulf of Aden	3	6.7	1	29	1.5× / 2
Missiles · Indian Oceannew	3	3.7	0	—	new / 0
Surveys · Arctic Oceanlong running	2	298.6	9	486	1.0× / 2
Cable ops · South China Sea	2	186.7	4	202	0.6× / 3.4
Surveys · Beaufort Sealong running	2	132.4	4	486	0.5× / 4
Cable ops · Gulf of Mexico	2	95.5	4	51	2.5× / 0.8
Cable ops · Persian Gulfnew	2	92.6	3	292	new / 0
Incidents · Caribbean Sea	2	83.6	2	38	2.5× / 0.8
Nav aids · Celtic Sea	2	75.2	3	82	1.3× / 1.6
Nav aids · Gulf of Mexico	2	66	2	212	0.5× / 4.4
Restricted · Sea of Okhotsknew	2	25.6	1	18	new / 0
Piracy · Mozambique Channelnew	2	21.9	0	—	new / 0
Surveys · Black Sea	2	19.4	1	55	2.5× / 0.8
Incidents · Tasman Sea	2	17.8	1	29	0.9× / 2.2
Incidents · Davis Strait	2	16	1	25	3.3× / 0.6
Exercises · Baltic Sea	2	14.3	0	—	1.1× / 1.8
Surveys · Mediterranean Sea - Eastern Basin	2	14.3	1	14	2.0× / 1
Missiles · Barentsz Sea	2	11.3	0	—	2.5× / 0.8
Exercises · Bering Sea	2	11.1	0	—	2.5× / 0.8
Missiles · South Pacific Ocean	2	10.8	0	—	10× / 0.2
Exercises · North Atlantic Ocean	2	9.4	0	—	0.3× / 6
Icebergs · Indian Ocean	2	6.7	0	—	10× / 0.2
Cable ops · Celtic Sea	2	6.4	0	—	1.0× / 2
Containers · North Pacific Ocean	2	6	0	—	3.3× / 0.6
Quakes · Philippine Sea	2	6	0	—	0.7× / 2.8
Quakes · Solomon Sea	2	6	0	—	1.1× / 1.8
Icebergs · South Pacific Ocean	2	6	0	—	2.0× / 1
Other · Inner Seas off the West Coast of Scotland	2	5.4	0	—	2.5× / 0.8
Quakes · Indian Ocean	2	4.5	1	18	0.5× / 4
Other · North Atlantic Ocean	2	4	0	—	2.0× / 1
Incidents · Arafura Sea	2	3.2	0	—	1.7× / 1.2
Nav aids · The Coastal Waters of Southeast Alaska and British Columbia	2	3	0	—	1.0× / 2
Nav aids · Inner Seas off the West Coast of Scotland	2	1.6	0	—	0.7× / 3
Derelicts · Coral Seanew	2	1.1	1	7	new / 0
Nav aids · Coral Sea	2	1	0	—	1.3× / 1.6
Other · Mediterranean Sea - Eastern Basin	1	99.2	2	42	2.5× / 0.4
Restricted · North Sea	1	58.9	1	70	new / 0
Nav aids · South China Sea	1	55.5	2	77	new / 0
Wrecks · North Atlantic Ocean	1	55	2	73	5.0× / 0.2
Cable ops · South Pacific Ocean	1	42.2	1	160	2.5× / 0.4
Nav aids · Mediterranean Sea - Western Basin	1	39	1	73	1.3× / 0.8
Ordnance · North Sealong running	1	38.2	2	1,095	1.3× / 0.8
Incidents · Ionian Sea	1	34.5	0	—	1.7× / 0.6
Nav aids · Laccadive Sea	1	31	1	34	5.0× / 0.2
Cable ops · Sea of Okhotsk	1	31	1	41	2.5× / 0.4
Restricted · North Atlantic Ocean	1	30.7	1	30	0.6× / 1.6
Wrecks · North Sea	1	28.3	1	28	new / 0
Other · Gulf of Thailand	1	27.9	1	27	new / 0
Incidents · Tyrrhenian Sea	1	27.8	0	—	1.7× / 0.6
Spills · North Pacific Ocean	1	24	0	—	0.7× / 1.4
Cable ops · Gulf of Thailand	1	21.4	1	21	2.5× / 0.4
Towing · Black Sea	1	18.8	0	—	5.0× / 0.2
Wrecks · Barentsz Sea	1	18.7	1	18	new / 0
Volcanic · North Atlantic Ocean	1	18.7	0	—	new / 0
Cable ops · Makassar Strait	1	16.7	1	16	2.5× / 0.4
Cable ops · Andaman or Burma Sea	1	16	0	—	5.0× / 0.2
Spills · South Pacific Ocean	1	14	0	—	new / 0
Spills · The Coastal Waters of Southeast Alaska and British Columbia	1	14	0	—	new / 0
Incidents · Arabian Sea	1	13.6	1	13	1.7× / 0.6
Incidents · Celtic Sea	1	13	0	—	1.3× / 0.8
Missiles · South Atlantic Ocean	1	11.8	1	11	5.0× / 0.2
Missiles · Sea of Okhotsk	1	8.9	0	—	5.0× / 0.2
Incidents · Gulf of Mexico	1	8.2	0	—	1.3× / 0.8
Cable ops · Arabian Sea	1	7.4	1	7	0.5× / 2.2
Surveys · Indian Ocean	1	7.4	1	7	1.0× / 1
Piracy · Sulu Sea	1	6.8	1	6	new / 0
Surveys · Sea of Okhotsk	1	6.6	1	70	5.0× / 0.2
Exercises · Sea of Okhotsk	1	6	0	—	1.3× / 0.8
Exercises · Adriatic Sea	1	5.6	0	—	2.5× / 0.4
Piracy · Singapore Strait	1	5.6	1	5	5.0× / 0.2
Derelicts · Arabian Sea	1	5.2	0	—	1.7× / 0.6
Debris · South Pacific Ocean	1	5	0	—	new / 0
Exercises · Andaman or Burma Sea	1	4.9	0	—	1.0× / 1
Missiles · Bay of Bengal	1	4.9	0	—	new / 0
Surveys · Arabian Sea	1	4.5	1	4	1.7× / 0.6
Exercises · Black Sea	1	3.9	0	—	1.0× / 1
Surveys · North Sea	1	3.9	0	—	1.7× / 0.6
Missiles · Laccadive Sea	1	3.2	0	—	2.5× / 0.4
Containers · Arabian Sea	1	3	0	—	new / 0
Quakes · Arafura Sea	1	3	0	—	5.0× / 0.2
Derelicts · Caribbean Sea	1	3	0	—	2.5× / 0.4
Derelicts · Mediterranean Sea - Western Basin	1	3	0	—	new / 0
Containers · North Atlantic Ocean	1	3	0	—	2.5× / 0.4
Quakes · North Atlantic Ocean	1	3	0	—	1.3× / 0.8
Derelicts · Philippine Sea	1	3	0	—	5.0× / 0.2
Derelicts · Sea of Okhotsk	1	3	0	—	new / 0
Derelicts · South China Sea	1	3	0	—	0.8× / 1.2
Derelicts · South Pacific Ocean	1	3	0	—	1.7× / 0.6
Derelicts · Tasman Sea	1	3	0	—	new / 0
Quakes · Tasman Sea	1	3	0	—	1.7× / 0.6
Derelicts · Timor Sea	1	3	0	—	2.5× / 0.4
Derelicts · Gulf of Mexico	1	2.5	0	—	new / 0
Missiles · Kara Sea	1	2.3	1	2	1.7× / 0.6
Incidents · Mozambique Channel	1	2.2	1	2	1.0× / 1
Exercises · Coral Sea	1	2.1	0	—	5.0× / 0.2
Quakes · Eastern China Sea	1	1.9	1	1	5.0× / 0.2
Incidents · Hudson Bay	1	1.6	0	—	new / 0
Surveys · Bay of Biscay	1	1.5	0	—	5.0× / 0.2
Incidents · Persian Gulf	1	1.3	1	1	new / 0
Other · South China Sea	1	1.3	0	—	new / 0
Incidents · Bering Sea	1	1.1	0	—	new / 0
Quakes · Bering Sea	1	0.7	1	0	5.0× / 0.2
Debris · Indian Ocean	1	0.6	1	0	5.0× / 0.2
Incidents · Bismarck Sea	1	0.5	0	—	5.0× / 0.2
Incidents · Solomon Sea	1	0.1	0	—	new / 0
Incidents · Timor Sea	1	0.1	0	—	0.8× / 1.2
Other · Indian Ocean	1	0	0	—	2.5× / 0.4
Exercises · Aegean Sea	0	155	5	305	0.0× / 1.4
Wrecks · The Northwestern Passageslong running	0	145.4	4	485	— / 0
Wrecks · Arabian Sealong running	0	117.8	3	684	— / 0
War risk · Mediterranean Sea - Eastern Basin	0	62.8	2	159	— / 0
Other · North Pacific Ocean	0	62.4	2	147	0.0× / 0.6
Surveys · Baffin Baylong running	0	62	2	486	— / 0
Nav aids · Hudson Bay	0	62	2	82	— / 0
Surveys · The Northwestern Passages	0	62	2	79	0.0× / 0.4
Cable ops · Mediterranean Sea - Eastern Basin	0	52.4	0	—	0.0× / 3.2
Nav aids · Irish Sea and St. George's Channel	0	38.4	1	82	0.0× / 2.6
Incidents · Laccadive Sea	0	36.2	0	—	0.0× / 0.2
Other · South Atlantic Ocean	0	33.5	1	172	0.0× / 1.4
Wrecks · South China Sealong running	0	31.8	1	405	0.0× / 0.6
Missiles · Aegean Sea	0	31	1	305	— / 0
Surveys · Barentsz Sea	0	31	1	61	— / 0
Nav aids · Bay of Bengal	0	31	1	47	0.0× / 0.2
Other · Bay of Bengal	0	31	1	189	0.0× / 0.2
Surveys · Bering Sealong running	0	31	1	443	0.0× / 0.2
Surveys · Davis Strait	0	31	1	164	— / 0
Nav aids · Kara Sea	0	31	1	54	— / 0
Other · Kara Sea	0	31	1	61	— / 0
Cable ops · Labrador Sea	0	31	1	38	0.0× / 0.2
Wrecks · Laccadive Sea	0	31	1	213	— / 0
Nav aids · Mediterranean Sea - Eastern Basinlong running	0	31	1	377	0.0× / 0.6
Surveys · Mozambique Channel	0	31	1	130	— / 0
Structures · North Sea	0	31	1	77	— / 0
Other · Persian Gulf	0	31	1	50	0.0× / 0.2
Restricted · Persian Gulf	0	31	1	333	— / 0
Surveys · Persian Gulf	0	31	1	173	— / 0
Wrecks · Persian Gulf	0	31	1	311	— / 0
Nav aids · Red Sea	0	31	1	287	— / 0
Cable ops · Sea of Marmara	0	31	1	32	0.0× / 0.2
Nav aids · Sea of Okhotsk	0	31	1	62	0.0× / 0.2
Wrecks · South Atlantic Oceanlong running	0	31	1	537	0.0× / 0.4
Cable ops · Tasman Sea	0	31	1	32	0.0× / 0.2
Other · The Northwestern Passageslong running	0	31	1	457	— / 0
Surveys · Japan Sea	0	28	0	—	0.0× / 0.4
Cable ops · Barentsz Sea	0	21.4	0	—	— / 0
Incidents · Labrador Sea	0	21.4	0	—	— / 0
Cable ops · Aegean Sea	0	18.6	0	—	0.0× / 0.6
Other · Sea of Okhotsk	0	15	0	—	0.0× / 0.2
Surveys · Chukchi Sea	0	14.8	0	—	— / 0
Other · Barentsz Sea	0	12.3	0	—	— / 0
Cable ops · Norwegian Sea	0	10	0	—	0.0× / 0.2
Other · Arctic Ocean	0	9.7	0	—	— / 0
Piracy · Red Sea	0	8.9	0	—	— / 0
Missiles · Southern Ocean	0	6.9	0	—	— / 0
Missiles · Arctic Ocean	0	4.2	0	—	0.0× / 0.2
Spills · Bering Sea	0	4	0	—	0.0× / 1
Surveys · North Pacific Ocean	0	1	0	—	0.0× / 0.2
Incidents · Adriatic Sea	0	0.4	0	—	— / 0

Cite: seahazards.com Sea Ledger, 2011-10, 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.