Sea Ledger, December 2011

2011-12-01 to 2011-12-31 · archive

issued: 433
warning-days in force: 6,448
in force at month end: 198
sea × type cells: 194

baseline: same month, previous 5 years (2010-12, 2009-12, 2008-12, 2007-12, 2006-12)

By type

type	issued	warning-days	in force at end
Nav aids	89	1,338.6	45
Incidents	89	825.7	16
Exercises	66	662.6	16
Cable ops	62	1,056	39
Quakes	27	86.5	1
Derelicts	25	89.7	2
Missiles	17	155.7	3
Other	14	253.6	8
Piracy	14	112.9	4
Surveys	9	872.5	27
Wrecks	5	573.2	19
Containers	4	8.3	2
Spills	4	77	3
Debris	3	7.1	0
Restricted	2	104.2	5
Icebergs	2	6	0
Mines	1	1.6	1
Volcanic	0	31	1
War risk	0	62	2
Ordnance	0	93	3
Structures	0	31	1

By sea and type · 194 cells, most issued first

cell	issued	warning-days	at end	longest d	vs 5 y
Nav aids · North Seasurge	29	298	9	67	2.6× / 11
Incidents · North Pacific Oceansurge	26	149.1	1	40	2.3× / 11.2
Cable ops · South Atlantic Oceanlong running	24	200.2	9	1,148	0.8× / 28.4
Exercises · North Pacific Oceansurge	18	65.2	2	35	2.3× / 8
Incidents · South China Seasurge	15	165.7	3	42	2.9× / 5.2
Nav aids · North Atlantic Oceansurgelong running	14	60.9	3	578	3.9× / 3.6
Quakes · South Pacific Ocean	13	37.8	1	31	1.1× / 11.4
Incidents · North Atlantic Ocean	12	219.3	3	73	1.1× / 10.8
Cable ops · North Atlantic Oceansurge	11	211.4	8	59	2.9× / 3.8
Exercises · Bay of Bengal	10	74.5	4	63	1.5× / 6.6
Exercises · South Atlantic Ocean	9	69.5	0	—	1.7× / 5.2
Nav aids · Inner Seas off the West Coast of Scotlandsurge	8	65.8	4	60	3.1× / 2.6
Incidents · Indian Oceansurge	8	45.4	1	52	2.2× / 3.6
Incidents · South Atlantic Oceansurge	7	69.3	2	76	2.2× / 3.2
Derelicts · South China Seasurge	7	15.5	1	22	4.4× / 1.6
Incidents · Coral Seasurge	7	0.7	0	—	2.7× / 2.6
Nav aids · South Atlantic Oceanlong running	6	277.8	9	1,228	1.3× / 4.6
Cable ops · Gulf of Guineasurge	6	57.7	3	64	6.0× / 1
Piracy · Arabian Sea	6	38	1	32	0.8× / 7.8
Exercises · Arabian Sea	5	67.4	1	70	1.3× / 4
Missiles · North Pacific Ocean	5	49.4	1	60	0.8× / 6.4
Exercises · Yellow Sea	5	39.3	1	38	1.0× / 5
Exercises · Aegean Seasurgelong running	4	157	4	366	2.0× / 2
Nav aids · North Pacific Ocean	4	103	3	230	1.5× / 2.6
Nav aids · Celtic Sea	4	66.5	2	88	1.7× / 2.4
Surveys · North Atlantic Oceansurge	4	10.6	0	—	5.0× / 0.8
Cable ops · North Seasurge	4	10.2	1	20	4.0× / 1
Nav aids · Coral Sea	4	1.3	0	—	1.1× / 3.6
Cable ops · Mediterranean Sea - Eastern Basin	3	53.6	2	41	0.8× / 4
Piracy · Indian Ocean	3	37.3	0	—	0.3× / 9.4
Nav aids · Irish Sea and St. George's Channel	3	30	1	119	1.1× / 2.8
Other · North Seasurge	3	12.9	0	—	2.5× / 1.2
Derelicts · Gulf of Mexicosurge	3	10.1	0	—	15× / 0.2
Quakes · Gulf of Tomininew	3	9	0	—	new / 0
Missiles · Philippine Seanew	3	7.4	0	—	new / 0
Nav aids · The Coastal Waters of Southeast Alaska and British Columbiasurge	3	0.6	1	25	2.5× / 1.2
Surveys · South Atlantic Ocean	2	81.7	1	70	0.9× / 2.2
Exercises · South China Sea	2	66.8	2	35	0.8× / 2.4
Other · North Pacific Ocean	2	66.1	2	208	2.5× / 0.8
Nav aids · Arabian Sealong running	2	64.4	2	512	0.9× / 2.2
Exercises · Philippine Sea	2	47.2	0	—	0.6× / 3.4
Nav aids · Gulf of Mexico	2	41.6	1	180	1.4× / 1.4
Nav aids · English Channel	2	32.5	1	50	1.1× / 1.8
Incidents · South Pacific Ocean	2	29.1	2	41	0.2× / 9
Cable ops · Black Sea	2	27	0	—	5.0× / 0.4
Missiles · South Atlantic Ocean	2	26.9	0	—	5.0× / 0.4
Cable ops · Bay of Bengal	2	26.7	1	31	0.7× / 3
Spills · Bering Sea	2	25	1	25	5.0× / 0.4
Piracy · Gulf of Aden	2	19.4	0	—	2.5× / 0.8
Nav aids · Sea of Okhotsknew	2	17.6	1	123	new / 0
Missiles · South Pacific Oceannew	2	13.1	0	—	new / 0
Incidents · Davis Straitnew	2	12.9	0	—	new / 0
Derelicts · South Pacific Ocean	2	11.7	1	19	3.3× / 0.6
Exercises · Baltic Sea	2	7	1	7	3.3× / 0.6
Derelicts · Indian Ocean	2	6	0	—	1.3× / 1.6
Quakes · Indian Ocean	2	6	0	—	0.6× / 3.2
Derelicts · Mozambique Channelnew	2	6	0	—	new / 0
Icebergs · Southern Ocean	2	5.4	0	—	0.6× / 3.4
Derelicts · North Atlantic Ocean	2	4.4	0	—	0.5× / 4
Debris · Tasman Seanew	2	4.1	0	—	new / 0
Other · Coral Sea	2	2.7	1	26	10× / 0.2
Incidents · Arabian Sea	2	2.2	2	2	2.0× / 1
Nav aids · Timor Sea	2	0.3	0	—	10× / 0.2
Cable ops · South China Sea	1	96.8	2	152	1.3× / 0.8
Cable ops · Gulf of Mexico	1	92.4	3	112	1.7× / 0.6
Wrecks · South Pacific Ocean	1	70.6	3	302	5.0× / 0.2
Cable ops · South Pacific Ocean	1	53.6	2	221	5.0× / 0.2
Incidents · Gulf of Mexico	1	44.2	0	—	2.5× / 0.4
Restricted · North Sea	1	41.1	2	131	new / 0
Nav aids · Mediterranean Sea - Eastern Basinlong running	1	34.6	1	438	1.0× / 1
Other · Bay of Bengal	1	34.5	2	57	2.5× / 0.4
Nav aids · Laccadive Sea	1	33.4	1	71	1.3× / 0.8
Missiles · Aegean Sealong running	1	31.4	2	366	5.0× / 0.2
Cable ops · Caribbean Sea	1	31	1	42	1.0× / 1
Surveys · Indian Ocean	1	31	1	68	1.7× / 0.6
Exercises · Laccadive Sea	1	29.7	0	—	0.3× / 4
Incidents · Bay of Bengal	1	23.8	1	23	0.8× / 1.2
Surveys · Chukchi Sea	1	22.4	1	22	new / 0
Cable ops · Sulu Sea	1	19.7	1	19	new / 0
Incidents · Mediterranean Sea - Eastern Basin	1	19.3	0	—	0.5× / 2
Wrecks · Sea of Okhotsk	1	18.6	1	18	new / 0
Cable ops · Irish Sea and St. George's Channel	1	16	1	15	2.5× / 0.4
Spills · Gulf of Alaska	1	14	1	14	5.0× / 0.2
Incidents · Sea of Okhotsk	1	13.6	1	13	new / 0
Cable ops · Eastern China Sea	1	13.4	0	—	1.0× / 1
Piracy · Malacca Strait	1	12.8	1	12	new / 0
Wrecks · Yellow Sea	1	12.7	1	12	new / 0
Cable ops · Laccadive Sea	1	12.5	1	12	5.0× / 0.2
Surveys · Laccadive Sea	1	11.4	1	41	2.5× / 0.4
Incidents · Persian Gulf	1	11.1	0	—	5.0× / 0.2
Other · South China Sea	1	11.1	0	—	new / 0
Derelicts · Caribbean Sea	1	10.1	0	—	0.6× / 1.6
Exercises · North Atlantic Ocean	1	10.1	0	—	0.1× / 7.6
Missiles · Japan Sea	1	9.8	0	—	1.3× / 0.8
Other · Southern Ocean	1	8.3	0	—	new / 0
Exercises · Barentsz Sea	1	7	0	—	new / 0
Spills · Gulf of Guinea	1	7	0	—	new / 0
Missiles · Barentsz Sea	1	6.8	0	—	1.7× / 0.6
Wrecks · Philippine Sea	1	6.7	0	—	new / 0
Exercises · South Pacific Ocean	1	6.3	0	—	0.3× / 3.4
Incidents · Caribbean Sea	1	6.2	0	—	0.5× / 2
Exercises · Mediterranean Sea - Eastern Basin	1	6.1	0	—	0.7× / 1.4
Missiles · Davis Strait	1	6	0	—	new / 0
Derelicts · Ionian Sea	1	5.4	0	—	new / 0
Missiles · Laccadive Sea	1	4.9	0	—	5.0× / 0.2
Exercises · Andaman or Burma Sea	1	4.8	0	—	1.7× / 0.6
Piracy · Singapore Strait	1	4.7	1	4	1.7× / 0.6
Other · Irish Sea and St. George's Channel	1	4.6	0	—	5.0× / 0.2
Incidents · Philippine Sea	1	4.3	0	—	0.4× / 2.4
Quakes · South Atlantic Ocean	1	4	0	—	0.7× / 1.4
Quakes · Solomon Sea	1	3.5	0	—	0.7× / 1.4
Cable ops · Gulf of Aden	1	3.4	0	—	new / 0
Quakes · Arafura Sea	1	3	0	—	new / 0
Containers · Caribbean Sea	1	3	0	—	2.5× / 0.4
Derelicts · Coral Sea	1	3	0	—	2.5× / 0.4
Quakes · Coral Sea	1	3	0	—	0.3× / 3
Derelicts · Gulf of Guinea	1	3	0	—	new / 0
Other · Java Sea	1	3	0	—	new / 0
Quakes · Makassar Strait	1	3	0	—	new / 0
Quakes · Molukka Sea	1	3	0	—	2.5× / 0.4
Quakes · North Atlantic Ocean	1	3	0	—	0.6× / 1.6
Containers · North Pacific Ocean	1	3	0	—	1.7× / 0.6
Quakes · North Pacific Ocean	1	3	0	—	0.1× / 7.4
Debris · North Sea	1	3	0	—	new / 0
Derelicts · Philippine Sea	1	3	0	—	new / 0
Quakes · Sea of Okhotsk	1	3	0	—	2.5× / 0.4
Exercises · Indian Ocean	1	2.7	0	—	2.5× / 0.4
Derelicts · South Atlantic Ocean	1	1.9	0	—	0.6× / 1.8
Mines · Kara Sea	1	1.6	1	1	new / 0
Containers · South China Sea	1	1.6	1	1	2.5× / 0.4
Restricted · Inner Seas off the West Coast of Scotland	1	1.1	1	1	new / 0
Exercises · Coral Sea	1	0.9	0	—	2.5× / 0.4
Nav aids · Tasman Sea	1	0.9	0	—	5.0× / 0.2
Piracy · Celebes Sea	1	0.7	1	0	new / 0
Containers · South Pacific Ocean	1	0.7	1	0	new / 0
Cable ops · Adriatic Sea	1	0.4	1	0	new / 0
Exercises · Ionian Sea	1	0.4	1	0	5.0× / 0.2
Nav aids · Great Australian Bight	1	0.3	0	—	1.0× / 1
Derelicts · North Pacific Ocean	1	0.2	0	—	0.5× / 2
Other · South Pacific Ocean	1	0.2	0	—	5.0× / 0.2
Wrecks · Bismarck Sea	1	0.1	0	—	new / 0
Incidents · Mediterranean Sea - Western Basin	1	0.1	0	—	new / 0
Other · Indian Ocean	1	0	0	—	1.7× / 0.6
Surveys · Arctic Oceanlong running	0	279	9	547	— / 0
Surveys · Beaufort Sealong running	0	124	4	507	— / 0
Wrecks · The Northwestern Passageslong running	0	124	4	482	— / 0
Wrecks · Arabian Sea	0	93	3	214	0.0× / 0.4
Ordnance · North Sealong running	0	93	3	1,156	0.0× / 0.2
Surveys · Baffin Baylong running	0	62	2	547	— / 0
War risk · Mediterranean Sea - Eastern Basin	0	62	2	220	— / 0
Nav aids · Mediterranean Sea - Western Basin	0	62	2	134	0.0× / 1.2
Wrecks · North Atlantic Ocean	0	62	2	134	— / 0
Cable ops · Persian Gulf	0	62	2	276	— / 0
Nav aids · South China Sea	0	62	2	138	— / 0
Surveys · The Northwestern Passages	0	62	2	140	— / 0
Other · Mediterranean Sea - Eastern Basin	0	41	1	100	0.0× / 1.2
Cable ops · Arabian Sea	0	31	1	68	0.0× / 4.2
Surveys · Barentsz Sea	0	31	1	122	— / 0
Surveys · Bering Sealong running	0	31	1	504	— / 0
Surveys · Davis Strait	0	31	1	225	— / 0
Surveys · Greenland Sea	0	31	1	59	— / 0
Wrecks · Irish Sea and St. George's Channel	0	31	1	33	— / 0
Nav aids · Kara Sea	0	31	1	115	— / 0
Surveys · Mediterranean Sea - Eastern Basin	0	31	1	36	0.0× / 1.6
Volcanic · North Atlantic Ocean	0	31	1	53	— / 0
Structures · North Sea	0	31	1	138	— / 0
Wrecks · North Sea	0	31	1	89	0.0× / 0.8
Other · Persian Gulf	0	31	1	111	0.0× / 0.2
Restricted · Persian Gulflong running	0	31	1	394	0.0× / 0.2
Surveys · Persian Gulf	0	31	1	234	0.0× / 0.2
Wrecks · Persian Gulflong running	0	31	1	372	0.0× / 0.4
Nav aids · Red Sea	0	31	1	348	0.0× / 0.2
Restricted · Sea of Okhotsk	0	31	1	79	— / 0
Spills · South Atlantic Ocean	0	31	1	50	— / 0
Wrecks · South Atlantic Oceanlong running	0	31	1	598	— / 0
Wrecks · South China Sealong running	0	31	1	411	— / 0
Other · The Northwestern Passageslong running	0	31	1	518	— / 0
Wrecks · Laccadive Sea	0	30.5	0	—	— / 0
Cable ops · Labrador Sea	0	23.4	0	—	— / 0
Nav aids · Bay of Bengal	0	13.7	0	—	0.0× / 0.4
Derelicts · Arabian Sea	0	9.4	0	—	0.0× / 0.4
Incidents · Ligurian Sea	0	9.4	0	—	— / 0
Nav aids · South Pacific Ocean	0	9.4	0	—	0.0× / 0.8
Cable ops · Tasman Sea	0	9.4	0	—	0.0× / 0.2
Cable ops · Strait of Gibraltar	0	4.2	0	—	0.0× / 0.2
Quakes · Andaman or Burma Sea	0	2.8	0	—	— / 0
Other · Caribbean Sea	0	2.4	0	—	0.0× / 0.4
Other · Kara Sea	0	2.4	0	—	— / 0
Surveys · Mozambique Channel	0	2.4	0	—	0.0× / 0.2
Other · North Atlantic Ocean	0	2.4	0	—	0.0× / 0.4
Quakes · South China Sea	0	2	0	—	0.0× / 0.8
Exercises · North Sea	0	0.7	0	—	— / 0
Icebergs · Labrador Sea	0	0.6	0	—	— / 0
Quakes · Java Sea	0	0.4	0	—	0.0× / 0.2

Cite: seahazards.com Sea Ledger, 2011-12, 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.