Sea Ledger, September 2011

2011-09-01 to 2011-09-30 · archive

issued: 427
warning-days in force: 6,613
in force at month end: 222
sea × type cells: 201

baseline: same month, previous 5 years (2010-09, 2009-09, 2008-09, 2007-09, 2006-09)

By type

type	issued	warning-days	in force at end
Exercises	87	782.7	27
Incidents	75	732.6	29
Cable ops	60	1,054.7	33
Nav aids	52	1,160.3	37
Quakes	37	117.1	1
Missiles	33	236.5	6
Derelicts	17	54.3	1
Piracy	15	81.9	8
Other	14	404.7	16
Surveys	11	1,011	33
Containers	6	16.4	0
Spills	6	110	2
Icebergs	4	11.3	1
Debris	4	12	0
Wrecks	4	525	18
Restricted	2	78.9	3
War risk	0	120	4
Ordnance	0	34.5	1
Structures	0	39.4	1
Volcanic	0	30	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	19	149.7	5	36	2.1× / 9
Exercises · South Atlantic Oceansurge	16	88.8	8	37	2.8× / 5.8
Quakes · North Pacific Oceansurge	14	42	0	—	3.3× / 4.2
Quakes · South Pacific Ocean	14	41.1	1	27	1.1× / 12.8
Cable ops · South Atlantic Oceanlong running	13	108.7	4	1,056	0.6× / 22.6
Cable ops · North Atlantic Oceansurge	12	130.7	2	94	4.6× / 2.6
Exercises · Bay of Bengalsurge	11	74.5	3	34	2.4× / 4.6
Exercises · North Pacific Ocean	10	62.2	1	34	1.1× / 8.8
Nav aids · North Sea	10	35.4	1	26	1.3× / 7.8
Incidents · South Atlantic Oceansurge	9	110.9	3	60	2.0× / 4.4
Missiles · North Atlantic Oceannew	9	60.5	0	—	new / 0
Nav aids · North Atlantic Oceanlong running	9	40.2	1	486	1.4× / 6.2
Missiles · North Pacific Ocean	8	55.6	3	61	1.1× / 7.6
Incidents · South Pacific Ocean	7	88.2	3	64	1.4× / 5
Exercises · Arabian Seasurge	7	65.5	2	30	2.5× / 2.8
Incidents · South China Seasurge	7	31.8	1	59	2.1× / 3.4
Piracy · Red Seasurge	7	30	5	20	35× / 0.2
Exercises · Yellow Sea	6	43.2	2	37	1.1× / 5.4
Cable ops · North Seasurge	5	51.4	2	77	2.8× / 1.8
Exercises · Laccadive Sea	5	27.4	1	37	0.9× / 5.6
Exercises · Coral Seasurge	5	21.7	0	—	8.3× / 0.6
Exercises · Baltic Seasurge	5	20.5	1	28	2.3× / 2.2
Containers · North Pacific Oceannew	5	15.9	0	—	new / 0
Derelicts · North Pacific Oceansurge	5	15	0	—	13× / 0.4
Exercises · Indian Oceansurge	5	12	0	—	2.5× / 2
Incidents · Indian Ocean	5	8.7	1	28	1.8× / 2.8
Nav aids · South Atlantic Oceanlong running	4	350.2	11	1,136	0.7× / 5.4
Cable ops · South China Sea	4	208.5	8	171	0.9× / 4.2
Wrecks · The Northwestern Passagessurgelong running	4	128.5	5	454	5.0× / 0.8
Nav aids · Gulf of Mexico	4	68.6	2	181	1.8× / 2.2
Spills · Gulf of Mexico	4	64	0	—	0.7× / 5.8
Incidents · Philippine Sea	4	23.1	1	24	0.9× / 4.2
Incidents · North Atlantic Ocean	4	21.2	3	15	0.7× / 6.2
Quakes · Coral Sea	4	12.8	0	—	1.8× / 2.2
Missiles · Philippine Seanew	4	8.3	0	—	new / 0
Nav aids · Gulf of Alaskasurge	4	2.3	1	28	2.5× / 1.6
Cable ops · Persian Gulfsurge	3	102.8	3	261	3.0× / 1
Cable ops · Mediterranean Sea - Eastern Basin	3	66.4	2	63	0.9× / 3.2
Cable ops · Gulf of Guinea	3	57.3	0	—	1.9× / 1.6
Cable ops · Gulf of Mexicosurge	3	50.5	2	129	3.8× / 0.8
Other · Mediterranean Sea - Eastern Basin	3	49.9	3	175	1.9× / 1.6
Surveys · Tasman Seanew	3	29.1	1	28	new / 0
Nav aids · Coral Sea	3	23.8	0	—	1.1× / 2.8
Cable ops · Black Seasurge	3	19.8	1	23	5.0× / 0.6
Cable ops · Sea of Marmarasurge	3	16	1	93	15× / 0.2
Piracy · Arabian Sea	3	10.1	1	27	1.9× / 1.6
Exercises · Black Sea	3	7.6	0	—	0.6× / 5.2
Nav aids · North Pacific Ocean	2	107.4	3	277	1.3× / 1.6
Nav aids · Arabian Sealong running	2	105	3	420	3.3× / 0.6
Exercises · South China Sea	2	95	2	37	0.6× / 3.4
Nav aids · Irish Sea and St. George's Channel	2	63.5	2	117	0.7× / 2.8
Exercises · Philippine Sea	2	62.7	1	34	0.5× / 4.4
Nav aids · South Pacific Ocean	2	47.4	2	218	1.4× / 1.4
Incidents · Laccadive Sea	2	45.6	3	45	2.5× / 0.8
Incidents · Gulf of Mexiconew	2	41	2	41	new / 0
Surveys · Black Sea	2	30.6	2	86	10× / 0.2
Cable ops · Aegean Seanew	2	28.1	1	22	new / 0
Cable ops · Barentsz Sea	2	26.6	1	122	10× / 0.2
Surveys · South Pacific Ocean	2	21.8	1	21	10× / 0.2
Nav aids · Bay of Bengal	2	20.5	1	22	5.0× / 0.4
Incidents · Ionian Sea	2	19.4	1	18	10× / 0.2
Incidents · Bay of Bengal	2	19.2	0	—	10× / 0.2
Piracy · Mozambique Channelnew	2	17.9	2	9	new / 0
Exercises · Sea of Okhotsk	2	13.3	0	—	2.0× / 1
Missiles · Bay of Bengal	2	11.9	0	—	10× / 0.2
Missiles · Arctic Oceannew	2	7.7	1	6	new / 0
Piracy · Indian Ocean	2	7.7	0	—	1.3× / 1.6
Debris · North Pacific Oceannew	2	6	0	—	new / 0
Derelicts · Indian Ocean	2	5.9	0	—	2.0× / 1
Icebergs · Indian Oceannew	2	5.3	1	19	new / 0
Derelicts · North Atlantic Ocean	2	5.1	1	4	1.7× / 1.2
Incidents · Coral Sea	2	4.1	1	23	1.0× / 2
Other · Bering Sea	2	2.2	0	—	10× / 0.2
Exercises · South Pacific Ocean	2	1.9	0	—	0.3× / 7.2
Nav aids · The Coastal Waters of Southeast Alaska and British Columbia	2	0.6	0	—	2.5× / 0.8
Other · Davis Strait	2	0.3	0	—	10× / 0.2
Incidents · Arafura Sea	2	0.2	0	—	10× / 0.2
Exercises · Aegean Sea	1	150	5	274	0.6× / 1.6
Surveys · South Atlantic Ocean	1	63	2	91	0.6× / 1.8
Other · North Pacific Ocean	1	62.6	3	116	5.0× / 0.2
Surveys · The Northwestern Passages	1	58.5	2	48	1.0× / 1
Restricted · North Sea	1	40.7	2	42	5.0× / 0.2
Other · South Atlantic Ocean	1	37.1	2	141	0.6× / 1.8
Other · The Northwestern Passageslong running	1	30.5	1	426	new / 0
Cable ops · Labrador Sea	1	30	1	45	1.0× / 1
Cable ops · Sea of Okhotsk	1	30	1	34	1.3× / 0.8
Exercises · Ionian Sea	1	28.8	0	—	new / 0
Incidents · Labrador Sea	1	24.8	1	24	new / 0
Other · Barentsz Sea	1	24.2	1	24	new / 0
Incidents · Gulf of Thailand	1	23.4	0	—	new / 0
Nav aids · Kara Sea	1	23.4	1	23	new / 0
Incidents · Mediterranean Sea - Eastern Basin	1	20.9	1	47	0.7× / 1.4
Other · Persian Gulf	1	19.7	1	19	new / 0
Spills · North Pacific Ocean	1	17	1	31	1.0× / 1
Missiles · Kara Sea	1	15.3	0	—	new / 0
Incidents · Singapore Strait	1	15.1	1	15	5.0× / 0.2
Piracy · Singapore Strait	1	13.8	0	—	new / 0
Missiles · South Atlantic Ocean	1	11.8	0	—	2.5× / 0.4
Derelicts · Bay of Bengal	1	11.6	0	—	2.5× / 0.4
Surveys · Celtic Sea	1	11.4	0	—	2.5× / 0.4
Spills · Bering Sea	1	10	1	10	5.0× / 0.2
Restricted · Sea of Okhotsk	1	8.2	0	—	new / 0
Incidents · Caribbean Sea	1	7.4	1	7	0.8× / 1.2
Cable ops · Irish Sea and St. George's Channel	1	7.4	0	—	new / 0
Missiles · Laccadive Sea	1	7.1	0	—	new / 0
Missiles · Japan Sea	1	6.8	0	—	5.0× / 0.2
Missiles · Barentsz Sea	1	6.6	0	—	1.7× / 0.6
Missiles · Black Sea	1	6	0	—	2.5× / 0.4
Missiles · Southern Ocean	1	4.9	1	4	new / 0
Exercises · Tasman Sea	1	4	0	—	new / 0
Nav aids · Laccadive Sea	1	3.5	1	3	1.7× / 0.6
Missiles · Gulf of Alaska	1	3.1	0	—	new / 0
Incidents · Mozambique Channel	1	3.1	0	—	1.3× / 0.8
Derelicts · Arabian Sea	1	3	0	—	new / 0
Debris · Arafura Sea	1	3	0	—	new / 0
Debris · Bay of Bengal	1	3	0	—	new / 0
Quakes · Bering Sea	1	3	0	—	1.3× / 0.8
Quakes · Bismarck Sea	1	3	0	—	5.0× / 0.2
Derelicts · Great Australian Bight	1	3	0	—	new / 0
Quakes · Indian Ocean	1	3	0	—	0.1× / 7.6
Icebergs · Kara Sea	1	3	0	—	new / 0
Derelicts · Philippine Sea	1	3	0	—	2.5× / 0.4
Quakes · South Atlantic Ocean	1	3	0	—	1.7× / 0.6
Icebergs · South Atlantic Ocean	1	3	0	—	0.3× / 3.8
Derelicts · South China Sea	1	3	0	—	0.7× / 1.4
Derelicts · South Pacific Ocean	1	3	0	—	2.5× / 0.4
Quakes · Tasman Sea	1	3	0	—	2.5× / 0.4
Surveys · Mediterranean Sea - Eastern Basin	1	2.7	0	—	1.3× / 0.8
Exercises · North Atlantic Ocean	1	2	0	—	0.1× / 10
Nav aids · Timor Sea	1	2	0	—	5.0× / 0.2
Cable ops · Tasman Sea	1	1.9	1	1	new / 0
Nav aids · Bristol Channel	1	1.7	0	—	5.0× / 0.2
Exercises · Andaman or Burma Sea	1	1.2	0	—	5.0× / 0.2
Other · Ionian Sea	1	1.2	0	—	new / 0
Derelicts · South Atlantic Ocean	1	0.9	0	—	0.4× / 2.4
Derelicts · Ionian Sea	1	0.8	0	—	new / 0
Nav aids · Inner Seas off the West Coast of Scotland	1	0.7	0	—	0.6× / 1.8
Other · Coral Sea	1	0.6	0	—	2.5× / 0.4
Containers · Beaufort Sea	1	0.5	0	—	new / 0
Exercises · Adriatic Sea	1	0.4	1	0	1.7× / 0.6
Incidents · Great Australian Bight	1	0.2	0	—	new / 0
Nav aids · Arafura Sea	1	0.1	0	—	1.3× / 0.8
Incidents · Bass Strait	1	0	0	—	5.0× / 0.2
Surveys · Arctic Oceanlong running	0	270	9	455	0.0× / 0.6
Wrecks · Arabian Sealong running	0	156.5	5	653	0.0× / 0.4
Surveys · Beaufort Sealong running	0	120	4	455	0.0× / 0.4
War risk · Mediterranean Sea - Eastern Basin	0	120	4	128	— / 0
Wrecks · South China Sealong running	0	90	3	374	0.0× / 0.2
Cable ops · Norwegian Sea	0	64.6	2	74	0.0× / 0.6
Surveys · Baffin Baylong running	0	61.6	2	455	0.0× / 0.2
Surveys · Chukchi Sealong running	0	60	2	383	0.0× / 0.2
Nav aids · Hudson Bay	0	60	2	51	— / 0
Structures · North Sea	0	39.4	1	71	0.0× / 0.4
Incidents · Adriatic Sea	0	30	1	47	0.0× / 0.6
Missiles · Aegean Sea	0	30	1	274	— / 0
Other · Arctic Ocean	0	30	1	85	0.0× / 0.2
Surveys · Barentsz Sea	0	30	1	30	— / 0
Other · Bay of Bengal	0	30	1	158	— / 0
Surveys · Bering Sealong running	0	30	1	412	0.0× / 0.2
Nav aids · Celtic Sea	0	30	1	51	0.0× / 1.6
Surveys · Davis Strait	0	30	1	133	0.0× / 0.2
Surveys · Japan Sea	0	30	1	34	0.0× / 0.2
Other · Kara Sea	0	30	1	30	— / 0
Wrecks · Laccadive Sea	0	30	1	182	0.0× / 0.2
Nav aids · Mediterranean Sea - Eastern Basin	0	30	1	346	0.0× / 0.2
Nav aids · Mediterranean Sea - Western Basin	0	30	1	42	0.0× / 0.6
Surveys · Mozambique Channel	0	30	1	99	— / 0
Wrecks · North Atlantic Ocean	0	30	1	42	0.0× / 0.4
Surveys · North Pacific Ocean	0	30	1	91	0.0× / 0.2
Ordnance · North Sealong running	0	30	1	1,064	0.0× / 0.6
Restricted · Persian Gulf	0	30	1	302	— / 0
Surveys · Persian Gulf	0	30	1	142	0.0× / 0.2
Wrecks · Persian Gulf	0	30	1	280	0.0× / 0.6
Volcanic · Philippine Sealong running	0	30	1	581	— / 0
Nav aids · Red Sea	0	30	1	256	0.0× / 0.2
Nav aids · Sea of Okhotsk	0	30	1	31	0.0× / 0.2
Other · Sea of Okhotsk	0	30	1	105	0.0× / 0.4
Surveys · Sea of Okhotsk	0	30	1	39	— / 0
Wrecks · South Atlantic Oceanlong running	0	30	1	506	— / 0
Nav aids · South China Sea	0	30	1	46	0.0× / 0.2
Other · South China Sealong running	0	30	1	1,171	0.0× / 0.2
Cable ops · South Pacific Ocean	0	30	1	129	— / 0
Wrecks · South Pacific Ocean	0	30	1	210	0.0× / 0.2
Other · North Sea	0	26.4	0	—	0.0× / 0.8
Surveys · Caribbean Sea	0	23	0	—	0.0× / 0.4
Cable ops · Gulf of Thailand	0	20	0	—	0.0× / 0.2
Surveys · North Sea	0	19.3	0	—	0.0× / 2.6
Spills · North Atlantic Ocean	0	19	0	—	0.0× / 2.8
Incidents · Arabian Sea	0	18.8	0	—	0.0× / 1
Incidents · Andaman or Burma Sea	0	16.4	0	—	0.0× / 0.4
Nav aids · Caribbean Sea	0	15	0	—	0.0× / 0.2
Incidents · Tyrrhenian Sea	0	9.4	0	—	0.0× / 0.6
Nav aids · Black Sea	0	6.6	0	—	— / 0
Ordnance · Kara Sea	0	4.5	0	—	— / 0
Cable ops · Mozambique Channel	0	4	0	—	— / 0
Quakes · North Atlantic Ocean	0	2.5	0	—	0.0× / 0.8
Piracy · Gulf of Aden	0	2.4	0	—	0.0× / 0.6
Quakes · Solomon Sea	0	2.4	0	—	0.0× / 1.6
Nav aids · Tasman Sea	0	2.4	0	—	0.0× / 0.2
Quakes · Banda Sea	0	1.3	0	—	0.0× / 0.6

Cite: seahazards.com Sea Ledger, 2011-09, 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.