Sea Ledger, April 2012

2012-04-01 to 2012-04-30 · archive

issued: 468
warning-days in force: 6,914
in force at month end: 217
sea × type cells: 198

baseline: same month, previous 5 years (2011-04, 2010-04, 2009-04, 2008-04, 2007-04)

By type

type	issued	warning-days	in force at end
Incidents	96	872.9	26
Exercises	91	772.9	17
Quakes	59	162	8
Nav aids	47	1,415.9	45
Cable ops	36	667.8	22
Icebergs	32	42.7	2
Derelicts	29	97.3	3
Missiles	18	168.5	5
Surveys	16	1,145.4	37
Piracy	11	107	1
Other	10	297.3	8
Wrecks	8	553.1	20
Spills	5	81	4
Containers	3	9	0
Debris	3	36	1
Towing	2	3.8	1
Restricted	1	210	7
Volcanic	1	31.6	2
Ordnance	0	120	4
Structures	0	30	1
Mines	0	30	1
War risk	0	60	2

By sea and type · 198 cells, most issued first

cell	issued	warning-days	at end	longest d	vs 5 y
Quakes · Indian Oceansurge	19	51.4	2	24	5.3× / 3.6
Incidents · North Pacific Ocean	18	139.2	1	64	1.4× / 13.2
Incidents · South China Seasurge	18	132	3	51	5.3× / 3.4
Cable ops · South Atlantic Ocean	17	178	6	95	0.6× / 27.8
Icebergs · Labrador Seanew	17	17.8	2	24	new / 0
Nav aids · North Seasurge	15	313.8	13	165	3.3× / 4.6
Exercises · North Pacific Ocean	15	51.4	2	33	1.2× / 12.8
Incidents · North Atlantic Oceansurge	13	146.7	5	39	2.4× / 5.4
Derelicts · North Atlantic Oceansurge	13	32.6	2	29	11× / 1.2
Quakes · North Pacific Ocean	12	32.9	2	29	1.4× / 8.4
Exercises · North Atlantic Ocean	11	47.9	1	30	2.0× / 5.6
Exercises · Mediterranean Sea - Eastern Basinsurge	11	19	1	26	14× / 0.8
Icebergs · Gulf of St. Lawrencenew	11	12.9	0	—	new / 0
Exercises · South Atlantic Ocean	10	65.6	0	—	1.4× / 7.2
Quakes · South Pacific Ocean	10	27.3	2	29	1.1× / 9.2
Incidents · South Pacific Ocean	9	60.8	1	44	1.7× / 5.4
Exercises · Arabian Seasurge	8	77.3	1	33	2.1× / 3.8
Exercises · Black Seasurge	7	67.3	0	—	5.0× / 1.4
Derelicts · North Pacific Oceansurge	7	8.5	0	—	2.2× / 3.2
Nav aids · North Atlantic Oceansurgelong running	6	87.8	3	699	2.3× / 2.6
Exercises · Bay of Bengal	6	79.9	1	34	1.1× / 5.4
Nav aids · South Atlantic Oceanlong running	5	321.7	9	1,349	1.3× / 3.8
Surveys · South Atlantic Oceansurge	5	242	7	110	2.3× / 2.2
Cable ops · North Atlantic Ocean	5	86.5	1	97	1.1× / 4.4
Exercises · Yellow Sea	5	42.1	1	32	1.1× / 4.6
Wrecks · Arabian Seanew	4	51.4	2	62	new / 0
Missiles · North Pacific Ocean	4	39.5	1	57	0.6× / 7.2
Piracy · Arabian Sea	4	33.7	0	—	0.8× / 4.8
Nav aids · Inner Seas off the West Coast of Scotland	4	32.1	1	181	1.1× / 3.6
Derelicts · Indian Oceansurge	4	12	0	—	2.5× / 1.6
Quakes · South Atlantic Ocean	4	12	0	—	1.8× / 2.2
Icebergs · Southern Oceansurge	4	12	0	—	2.5× / 1.6
Incidents · Indian Ocean	4	10	0	—	1.5× / 2.6
Nav aids · Irish Sea and St. George's Channelsurge	4	4.7	0	—	2.9× / 1.4
Nav aids · Coral Seasurge	4	3.3	0	—	2.2× / 1.8
Incidents · Great Australian Bightsurge	4	0.3	0	—	10× / 0.4
Exercises · South China Seasurge	3	72.7	2	33	2.1× / 1.4
Incidents · South Atlantic Ocean	3	51.4	2	35	0.6× / 5.2
Incidents · Mozambique Channelsurge	3	40.8	2	64	7.5× / 0.4
Cable ops · Gulf of Guinea	3	31.5	1	24	1.9× / 1.6
Spills · Gulf of Mexico	3	29	2	22	0.8× / 3.8
Incidents · Arabian Seasurge	3	17.6	0	—	3.0× / 1
Cable ops · Gulf of Mexico	3	13.2	2	13	1.7× / 1.8
Surveys · North Atlantic Ocean	3	6.3	1	6	1.9× / 1.6
Nav aids · English Channel	2	90.2	3	51	0.7× / 3
Nav aids · North Pacific Ocean	2	84.2	2	351	0.7× / 3
Cable ops · Persian Gulf	2	64	2	102	1.3× / 1.6
Other · North Pacific Ocean	2	59.6	2	329	2.0× / 1
Incidents · Andaman or Burma Sea	2	47.3	2	27	10× / 0.2
Exercises · Philippine Sea	2	47.3	1	37	0.7× / 3
Surveys · Mediterranean Sea - Eastern Basin	2	43	2	93	1.1× / 1.8
Piracy · Indian Ocean	2	41.5	0	—	0.4× / 5
Wrecks · Mediterranean Sea - Eastern Basinnew	2	40.3	2	97	new / 0
Debris · South Pacific Oceannew	2	36	1	55	new / 0
Exercises · Laccadive Sea	2	27.5	1	26	0.5× / 4.2
Exercises · Baltic Sea	2	23.9	0	—	0.8× / 2.4
Other · Indian Ocean	2	20.4	1	20	10× / 0.2
Missiles · South Atlantic Ocean	2	14.8	0	—	2.5× / 0.8
Piracy · Gulf of Omannew	2	8.1	0	—	new / 0
Incidents · Bay of Biscay	2	6.3	1	19	3.3× / 0.6
Quakes · Andaman or Burma Seanew	2	6	0	—	new / 0
Derelicts · Celtic Sea	2	6	0	—	10× / 0.2
Quakes · Gulf of California	2	6	0	—	5.0× / 0.4
Containers · North Pacific Ocean	2	6	0	—	1.7× / 1.2
Exercises · Indian Ocean	2	5.9	0	—	2.0× / 1
Exercises · Japan Sea	2	5.5	1	23	0.3× / 5.8
Missiles · South Pacific Ocean	2	4.5	0	—	1.7× / 1.2
Exercises · South Pacific Ocean	2	4	1	23	0.6× / 3.2
Towing · South China Seanew	2	3.8	1	3	new / 0
Quakes · Banda Sea	2	3.2	1	14	1.0× / 2
Incidents · Southern Ocean	2	1.6	0	—	10× / 0.2
Incidents · Philippine Sea	2	0.4	0	—	0.4× / 5.4
Incidents · Coral Sea	2	0.3	0	—	0.6× / 3.2
Incidents · Tasman Sea	2	0.2	1	23	1.7× / 1.2
Restricted · North Sea	1	120	4	252	new / 0
Nav aids · Arabian Sealong running	1	88.9	3	633	1.3× / 0.8
Wrecks · South China Sealong running	1	79.4	3	532	new / 0
Cable ops · North Sea	1	61.9	3	36	0.6× / 1.8
Nav aids · Celtic Sea	1	60	2	90	0.5× / 2.2
Other · North Sea	1	59	2	102	0.8× / 1.2
Incidents · Caribbean Sea	1	42	1	57	0.8× / 1.2
Incidents · Tyrrhenian Sea	1	40.6	2	106	0.8× / 1.2
Cable ops · Arabian Sea	1	36.6	2	49	0.4× / 2.8
Cable ops · Mozambique Channel	1	34.9	1	47	1.7× / 0.6
Other · South Pacific Ocean	1	33.9	0	—	1.7× / 0.6
Incidents · Gulf of Mexico	1	32	2	38	2.5× / 0.4
Incidents · Eastern China Sea	1	26.2	1	26	1.7× / 0.6
Surveys · North Sea	1	25.9	0	—	1.7× / 0.6
Surveys · Black Sea	1	24.4	0	—	2.5× / 0.4
Wrecks · Caribbean Sea	1	21	1	21	new / 0
Surveys · Gulf of Suez	1	17.6	1	17	5.0× / 0.2
Missiles · Japan Sea	1	17.6	0	—	1.3× / 0.8
Missiles · Norwegian Sea	1	17.1	1	17	new / 0
Other · Arabian Sea	1	15	0	—	new / 0
Spills · Bay of Fundy	1	14	0	—	new / 0
Piracy · South China Sea	1	11.4	0	—	0.4× / 2.4
Cable ops · Norwegian Sea	1	10	1	9	1.7× / 0.6
Surveys · Indian Ocean	1	8.9	0	—	0.8× / 1.2
Missiles · Black Sea	1	8.8	0	—	new / 0
Exercises · Barentsz Sea	1	8.1	0	—	new / 0
Piracy · Mozambique Channel	1	7.9	0	—	new / 0
Missiles · Barentsz Sea	1	7.7	0	—	1.3× / 0.8
Surveys · Mozambique Channel	1	7.6	1	7	0.8× / 1.2
Missiles · Philippine Sea	1	7.1	0	—	new / 0
Spills · North Pacific Ocean	1	7	1	7	0.6× / 1.8
Missiles · Bay of Bengal	1	6.9	0	—	2.5× / 0.4
Cable ops · Celtic Sea	1	6	0	—	0.4× / 2.4
Nav aids · South Pacific Ocean	1	5.8	0	—	0.8× / 1.2
Nav aids · Persian Gulf	1	5	0	—	new / 0
Missiles · Arabian Sea	1	4.8	0	—	2.5× / 0.4
Piracy · Gulf of Aden	1	4.4	1	4	0.6× / 1.6
Missiles · Kara Sea	1	4.3	0	—	new / 0
Exercises · Andaman or Burma Sea	1	3.9	0	—	1.0× / 1
Other · Davis Strait	1	3.9	1	3	new / 0
Incidents · Singapore Strait	1	3.9	0	—	new / 0
Missiles · Laccadive Sea	1	3.7	1	3	5.0× / 0.2
Exercises · Persian Gulf	1	3.6	0	—	5.0× / 0.2
Quakes · Arabian Sea	1	3	0	—	5.0× / 0.2
Quakes · Bismarck Sea	1	3	0	—	1.7× / 0.6
Quakes · Coral Sea	1	3	0	—	0.2× / 4.2
Other · Coral Sea	1	3	0	—	5.0× / 0.2
Quakes · Ionian Sea	1	3	0	—	new / 0
Quakes · Java Sea	1	3	0	—	new / 0
Quakes · Molukka Sea	1	3	0	—	0.8× / 1.2
Quakes · Philippine Sea	1	3	0	—	0.4× / 2.4
Containers · South China Sea	1	3	0	—	new / 0
Derelicts · South Pacific Ocean	1	3	0	—	0.8× / 1.2
Derelicts · Tasman Sea	1	3	0	—	2.5× / 0.4
Incidents · Davis Strait	1	2.8	1	2	5.0× / 0.2
Surveys · Baltic Sea	1	2.7	0	—	new / 0
Quakes · Solomon Sea	1	2.2	1	2	0.1× / 8.2
Cable ops · English Channel	1	2.1	0	—	0.5× / 2.2
Derelicts · South China Sea	1	1.8	0	—	0.8× / 1.2
Missiles · North Atlantic Ocean	1	1.7	1	1	0.8× / 1.2
Volcanic · Philippine Sea	1	1.6	1	1	1.7× / 0.6
Incidents · Gulf of St. Lawrence	1	1.1	0	—	new / 0
Other · Philippine Sea	1	0.7	0	—	new / 0
Nav aids · Barentsz Sea	1	0.6	0	—	new / 0
Incidents · Java Sea	1	0.2	0	—	5.0× / 0.2
Incidents · Arafura Sea	1	0.1	0	—	new / 0
Debris · Arabian Sea	1	0	0	—	new / 0
Surveys · Arctic Oceanlong running	0	300	10	668	0.0× / 0.2
Surveys · Beaufort Sealong running	0	120	4	628	— / 0
Ordnance · North Sealong running	0	120	4	1,277	0.0× / 0.8
Wrecks · The Northwestern Passageslong running	0	120	4	603	— / 0
Exercises · Aegean Sea	0	90	3	121	— / 0
Nav aids · Mediterranean Sea - Western Basin	0	64.4	1	255	0.0× / 0.8
Surveys · Baffin Baylong running	0	60	2	668	— / 0
Nav aids · Gulf of Mexico	0	60	2	174	0.0× / 2.8
War risk · Mediterranean Sea - Eastern Basin	0	60	2	341	— / 0
Wrecks · North Atlantic Ocean	0	60	2	255	— / 0
Nav aids · South China Sea	0	60	2	259	0.0× / 0.2
Surveys · The Northwestern Passages	0	60	2	261	— / 0
Cable ops · South China Sea	0	34.6	1	43	0.0× / 2
Incidents · Mediterranean Sea - Eastern Basin	0	33.8	0	—	0.0× / 0.8
Missiles · Aegean Sea	0	30	1	121	— / 0
Cable ops · Andaman or Burma Sea	0	30	1	60	0.0× / 0.4
Surveys · Arabian Sea	0	30	1	33	0.0× / 0.8
Surveys · Barentsz Sea	0	30	1	32	— / 0
Surveys · Bering Sealong running	0	30	1	625	— / 0
Nav aids · Bristol Channel	0	30	1	82	— / 0
Surveys · Chukchi Sea	0	30	1	143	— / 0
Surveys · Davis Strait	0	30	1	346	— / 0
Nav aids · Eastern China Sea	0	30	1	76	— / 0
Surveys · Greenland Sea	0	30	1	101	— / 0
Derelicts · Gulf of Oman	0	30	1	119	— / 0
Exercises · Ionian Sea	0	30	1	121	— / 0
Nav aids · Kara Sea	0	30	1	236	— / 0
Mines · Kara Sea	0	30	1	122	— / 0
Incidents · Laccadive Sea	0	30	1	40	0.0× / 0.4
Structures · North Sea	0	30	1	259	0.0× / 0.4
Wrecks · North Sea	0	30	1	210	0.0× / 0.2
Other · Persian Gulf	0	30	1	232	— / 0
Restricted · Persian Gulflong running	0	30	1	515	— / 0
Surveys · Persian Gulf	0	30	1	355	0.0× / 0.6
Wrecks · Persian Gulflong running	0	30	1	493	— / 0
Volcanic · Red Sea	0	30	1	114	— / 0
Nav aids · Sea of Okhotsk	0	30	1	132	— / 0
Restricted · Sea of Okhotsk	0	30	1	200	— / 0
Wrecks · Sea of Okhotsk	0	30	1	139	— / 0
Spills · South Atlantic Ocean	0	30	1	171	— / 0
Restricted · South Atlantic Ocean	0	30	1	80	0.0× / 0.2
Wrecks · South Atlantic Oceanlong running	0	30	1	719	— / 0
Cable ops · South Pacific Ocean	0	30	1	342	0.0× / 1.4
Wrecks · South Pacific Oceanlong running	0	30	1	423	— / 0
Other · The Northwestern Passageslong running	0	30	1	639	— / 0
Wrecks · Yellow Sea	0	30	1	133	— / 0
Other · Mediterranean Sea - Eastern Basin	0	26.8	0	—	0.0× / 1.4
Cable ops · Indian Ocean	0	18.5	0	—	0.0× / 0.6
Surveys · Philippine Sea	0	17	0	—	0.0× / 0.2
Other · Bay of Bengal	0	15	0	—	0.0× / 0.2
Cable ops · Gulf of Aden	0	15	0	—	— / 0
Cable ops · Malacca Strait	0	15	0	—	— / 0
Nav aids · Andaman or Burma Sea	0	13.4	0	—	0.0× / 0.2
Incidents · Bismarck Sea	0	5.3	0	—	0.0× / 0.4
Wrecks · Coral Sea	0	1	0	—	— / 0
Spills · The Coastal Waters of Southeast Alaska and British Columbia	0	1	0	—	0.0× / 0.2
Derelicts · Eastern China Sea	0	0.4	0	—	— / 0

Cite: seahazards.com Sea Ledger, 2012-04, 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.