Sea Ledger, September 2017

2017-09-01 to 2017-09-30 · archive

issued: 817
warning-days in force: 14,632
in force at month end: 502
sea × type cells: 279

baseline: same month, previous 5 years (2016-09, 2015-09, 2014-09, 2013-09, 2012-09)

By type

type	issued	warning-days	in force at end
Incidents	153	1,633.1	48
Exercises	147	1,280.2	45
Surveys	111	3,074.5	108
Nav aids	103	3,631.2	136
Icebergs	75	94.8	5
Missiles	42	355.5	16
Quakes	37	110.5	2
Derelicts	34	187.5	3
Cable ops	21	543.2	11
Wrecks	18	2,098.3	72
Other	17	676.4	19
Spills	16	217	12
Storms	14	86.9	4
Piracy	10	43.3	4
Containers	6	18	0
Debris	5	15	0
Ordnance	5	158.8	5
Restricted	3	228.2	6
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 Sea	30	259.5	8	46	1.8× / 17
Exercises · North Pacific Ocean	27	184.5	6	65	1.0× / 26.8
Icebergs · North Atlantic Oceannew	25	30.8	0	—	new / 0
Incidents · North Pacific Ocean	22	231.8	6	43	0.7× / 31.8
Exercises · South Atlantic Oceansurge	22	121.7	4	31	2.6× / 8.6
Icebergs · South Atlantic Oceansurge	22	23.4	1	22	2.7× / 8.2
Surveys · Mediterranean Sea - Eastern Basinsurge	20	179.8	5	85	17× / 1.2
Incidents · Mediterranean Sea - Eastern Basin	19	301.9	8	46	1.1× / 17
Quakes · North Pacific Oceansurge	19	54.5	0	—	2.5× / 7.6
Surveys · South Atlantic Oceansurge	18	150.5	7	164	4.3× / 4.2
Exercises · Aegean Seasurge	16	354.3	11	275	5.3× / 3
Exercises · Black Sea	16	115	6	123	1.9× / 8.6
Missiles · North Pacific Oceansurge	16	106.2	3	182	2.0× / 8
Incidents · North Atlantic Ocean	15	170.5	5	47	1.2× / 12.8
Nav aids · South Atlantic Ocean	14	374.6	15	157	1.8× / 7.8
Nav aids · North Atlantic Oceansurgelong running	13	225.5	14	1,592	3.4× / 3.8
Exercises · Bay of Bengal	13	81.2	3	37	1.8× / 7.4
Icebergs · Southern Oceannew	13	12.9	0	—	new / 0
Incidents · Caribbean Seasurge	12	124.2	6	37	3.2× / 3.8
Exercises · North Atlantic Ocean	12	65.9	2	30	1.6× / 7.6
Nav aids · Inner Seas off the West Coast of Scotlandsurge	10	185.5	7	129	3.3× / 3
Incidents · South Atlantic Ocean	9	91.3	1	49	1.1× / 8.2
Exercises · Arabian Sea	9	62.8	3	32	1.6× / 5.6
Surveys · North Seasurge	9	48.4	3	95	11× / 0.8
Surveys · Caribbean Seasurge	8	122.6	5	261	20× / 0.4
Spills · Gulf of Mexicosurge	8	113	7	39	2.9× / 2.8
Storms · Caribbean Seanew	8	53.8	3	22	new / 0
Nav aids · Caribbean Seasurgelong running	7	660	25	464	12× / 0.6
Nav aids · Gulf of Mexico	7	354.4	12	239	1.8× / 3.8
Surveys · North Atlantic Oceanlong running	7	261.5	10	590	1.9× / 3.6
Nav aids · North Sea	7	152.6	4	87	0.7× / 10
Surveys · South China Seasurge	7	127.4	6	59	18× / 0.4
Missiles · Black Sea	7	51.3	3	30	1.5× / 4.8
Icebergs · Labrador Sea	7	5.7	4	4	0.2× / 30.2
Incidents · Coral Sea	7	3.6	1	26	1.4× / 5.2
Surveys · Black Seasurge	6	124.5	6	59	3.8× / 1.6
Surveys · Bay of Bengalsurgelong running	6	121.1	2	449	30× / 0.2
Incidents · Indian Ocean	6	70.1	2	86	0.6× / 10.4
Missiles · Barentsz Sea	6	33.5	1	37	1.1× / 5.4
Nav aids · The Coastal Waters of Southeast Alaska and British Columbiasurge	6	29.3	1	29	3.3× / 1.8
Icebergs · Laptev Seasurge	6	18	0	—	2.0× / 3
Derelicts · Bay of Bengalsurge	6	17.1	0	—	15× / 0.4
Exercises · Mediterranean Sea - Eastern Basin	6	16	0	—	1.0× / 5.8
Surveys · Barentsz Seasurge	5	145.9	5	74	25× / 0.2
Derelicts · North Pacific Oceansurge	5	43	0	—	2.8× / 1.8
Nav aids · English Channel	5	13.4	1	12	1.5× / 3.4
Cable ops · Tyrrhenian Seanew	5	7.8	0	—	new / 0
Nav aids · South Pacific Oceansurgelong running	4	280.1	11	390	4.0× / 1
Surveys · Kara Seasurge	4	193.9	7	96	5.0× / 0.8
Nav aids · North Pacific Ocean	4	170	6	346	1.1× / 3.8
Wrecks · Arabian Seasurge	4	169.8	6	345	6.7× / 0.6
Incidents · Gulf of Mexico	4	73.2	2	46	1.4× / 2.8
Nav aids · Davis Straitsurge	4	62.8	2	107	2.9× / 1.4
Nav aids · Celtic Seasurge	4	34.7	1	171	4.0× / 1
Cable ops · North Sea	4	32.6	0	—	0.5× / 7.4
Storms · Gulf of Mexiconew	4	32.2	1	30	new / 0
Incidents · Solomon Seasurge	4	16.9	0	—	4.0× / 1
Derelicts · North Atlantic Ocean	4	9.9	0	—	1.3× / 3
Other · The Northwestern Passages	4	7.8	0	—	1.8× / 2.2
Ordnance · North Seasurge	3	63.4	2	59	2.5× / 1.2
Incidents · Davis Strait	3	55.1	0	—	1.1× / 2.8
Wrecks · South Pacific Oceansurge	3	36.9	3	128	7.5× / 0.4
Spills · North Pacific Oceansurge	3	35	2	37	2.1× / 1.4
Incidents · Philippine Sea	3	34.3	1	29	0.5× / 6
Incidents · South Pacific Ocean	3	29.1	1	45	0.4× / 6.8
Exercises · Yellow Sea	3	17.9	0	—	0.3× / 9.6
Derelicts · Caribbean Seasurge	3	15.9	1	11	15× / 0.2
Piracy · South China Seasurge	3	14.2	0	—	3.0× / 1
Exercises · South China Sea	3	13.2	0	—	0.5× / 6.2
Exercises · Baltic Sea	3	9.6	0	—	0.8× / 4
Quakes · South Atlantic Oceansurge	3	9	0	—	3.0× / 1
Quakes · South Pacific Ocean	3	9	0	—	0.2× / 19
Missiles · Indian Oceansurge	3	8.3	0	—	3.8× / 0.8
Exercises · South Pacific Ocean	3	7.3	0	—	0.5× / 6.6
Incidents · Java Seasurge	3	7.1	1	27	2.5× / 1.2
Quakes · Philippine Seasurge	3	5.6	2	23	2.5× / 1.2
Nav aids · Irish Sea and St. George's Channel	3	3.8	0	—	0.7× / 4.6
Wrecks · Caribbean Sealong running	2	327.4	11	441	5.0× / 0.4
Surveys · Norwegian Seanew	2	272.9	5	169	new / 0
Wrecks · South Atlantic Oceannew	2	144.2	3	232	new / 0
Surveys · The Northwestern Passageslong running	2	131.7	6	1,881	5.0× / 0.4
Nav aids · Arabian Sea	2	117.5	4	156	1.4× / 1.4
Missiles · North Atlantic Ocean	2	99.7	5	33	0.3× / 6.4
Other · Hudson Baynew	2	82.6	2	75	new / 0
Surveys · Celtic Sea	2	74.1	3	102	3.3× / 0.6
Other · North Atlantic Ocean	2	64.1	1	82	2.0× / 1
Other · Indian Ocean	2	56.4	1	155	3.3× / 0.6
Other · Black Sea	2	43.4	1	36	1.7× / 1.2
Exercises · Philippine Sea	2	35.6	2	30	0.4× / 4.8
Nav aids · Great Australian Bightlong running	2	30.7	1	668	1.3× / 1.6
Derelicts · South Pacific Ocean	2	30	1	30	1.4× / 1.4
Exercises · Laccadive Sea	2	29.2	2	32	1.7× / 1.2
Spills · North Atlantic Ocean	2	26	1	26	1.3× / 1.6
Spills · Caribbean Sea	2	23	2	12	10× / 0.2
Incidents · Gulf of Thailand	2	22.5	2	38	10× / 0.2
Nav aids · Laccadive Seanew	2	16.9	2	8	new / 0
Exercises · Japan Seanew	2	15.3	0	—	new / 0
Piracy · Gulf of Adennew	2	11.5	1	8	new / 0
Cable ops · South China Sea	2	9.7	1	13	0.8× / 2.6
Derelicts · Mediterranean Sea - Western Basin	2	7.6	0	—	5.0× / 0.4
Piracy · North Atlantic Ocean	2	7.4	0	—	10× / 0.2
Cable ops · Eastern China Sea	2	7.2	0	—	3.3× / 0.6
Containers · Arafura Seanew	2	6	0	—	new / 0
Debris · Caribbean Sea	2	6	0	—	10× / 0.2
Quakes · Coral Sea	2	6	0	—	3.3× / 0.6
Missiles · Laccadive Sea	2	6	1	15	2.0× / 1
Quakes · North Atlantic Ocean	2	6	0	—	3.3× / 0.6
Containers · Norwegian Seanew	2	6	0	—	new / 0
Quakes · Solomon Sea	2	6	0	—	1.0× / 2
Derelicts · Tasman Seanew	2	6	0	—	new / 0
Ordnance · Bristol Channelnew	2	5.4	0	—	new / 0
Missiles · Southern Ocean	2	5.3	0	—	10× / 0.2
Derelicts · Coral Sea	2	3.6	0	—	10× / 0.2
Storms · North Atlantic Oceannew	2	0.9	0	—	new / 0
Surveys · Arctic Oceanlong running	1	235.6	7	1,166	0.8× / 1.2
Wrecks · North Sea	1	180	6	185	2.5× / 0.4
Surveys · Beaufort Sealong running	1	122.1	5	1,827	2.5× / 0.4
Nav aids · Coral Sealong running	1	120.1	4	1,261	0.3× / 3.2
Surveys · Sea of Okhotsk	1	101.6	2	299	5.0× / 0.2
Cable ops · Caribbean Sea	1	83.5	1	288	0.4× / 2.4
Surveys · Japan Sea	1	71.6	3	122	new / 0
Restricted · Black Sealong running	1	71.3	1	1,578	5.0× / 0.2
Other · South China Sealong running	1	66.6	2	1,039	0.8× / 1.2
Cable ops · Davis Strait	1	62.9	2	52	new / 0
Nav aids · Indian Oceanlong running	1	60.2	2	811	0.5× / 2.2
Wrecks · Irish Sea and St. George's Channel	1	60	2	264	new / 0
Surveys · Malacca Strait	1	58.7	2	44	new / 0
Surveys · Laptev Sea	1	57.7	2	67	new / 0
Nav aids · Andaman or Burma Sea	1	50.1	1	208	5.0× / 0.2
Nav aids · Bay of Bengal	1	49.6	2	169	1.7× / 0.6
Wrecks · The Northwestern Passages	1	48.7	2	35	0.8× / 1.2
Wrecks · Indian Ocean	1	48.6	2	86	new / 0
Nav aids · Bristol Channel	1	41.9	1	135	5.0× / 0.2
Exercises · Sea of Okhotsk	1	39.5	1	40	5.0× / 0.2
Nav aids · Bass Straitlong running	1	30.2	1	882	2.5× / 0.4
Wrecks · Bristol Channel	1	30	1	64	new / 0
Surveys · Sea of Marmara	1	30	1	87	2.5× / 0.4
Restricted · South Atlantic Ocean	1	26.6	0	—	1.0× / 1
Cable ops · Bay of Bengal	1	26.2	1	26	5.0× / 0.2
Nav aids · Kara Sea	1	25.8	1	61	5.0× / 0.2
Surveys · Tasman Sea	1	24.9	1	24	5.0× / 0.2
Nav aids · Sea of Okhotsk	1	24.6	1	24	new / 0
Surveys · Coral Sea	1	23.2	1	39	5.0× / 0.2
Cable ops · Philippine Sea	1	23	0	—	1.7× / 0.6
Incidents · Mozambique Channel	1	22.7	1	31	0.4× / 2.6
Cable ops · North Atlantic Ocean	1	21.9	0	—	0.1× / 8.6
Surveys · Persian Gulf	1	19	0	—	5.0× / 0.2
Incidents · Eastern China Sea	1	18.5	0	—	new / 0
Incidents · Gulf of Aden	1	18.5	0	—	new / 0
Surveys · Davis Strait	1	17	1	17	1.3× / 0.8
Incidents · Bering Sea	1	16.7	0	—	new / 0
Wrecks · Kara Sea	1	16.5	1	16	new / 0
Surveys · Bay of Biscay	1	16.2	1	16	new / 0
Wrecks · English Channel	1	16.2	1	57	1.7× / 0.6
Incidents · Balearic (Iberian Sea)	1	14.7	0	—	new / 0
Spills · Gulf of Alaska	1	14	0	—	2.5× / 0.4
Incidents · The Northwestern Passages	1	13	1	12	0.5× / 2
Cable ops · Makassar Strait	1	12.4	0	—	new / 0
Restricted · Persian Gulf	1	10.3	1	10	new / 0
Surveys · Arabian Sea	1	9.5	1	9	1.7× / 0.6
Missiles · Laptev Sea	1	8.3	0	—	0.6× / 1.8
Exercises · Barentsz Sea	1	7.3	0	—	0.7× / 1.4
Cable ops · Arabian Sea	1	6.8	0	—	0.5× / 2
Piracy · Mediterranean Sea - Eastern Basin	1	5.9	1	5	new / 0
Derelicts · Indian Ocean	1	5.5	0	—	0.2× / 5
Cable ops · Mediterranean Sea - Eastern Basin	1	4.8	0	—	0.6× / 1.6
Exercises · Indian Ocean	1	4.7	0	—	0.4× / 2.8
Incidents · Bay of Bengal	1	4.5	1	4	0.7× / 1.4
Exercises · Coral Sea	1	4	0	—	0.4× / 2.6
Surveys · Baltic Sea	1	3.6	1	3	new / 0
Incidents · Ionian Sea	1	3.4	1	3	1.7× / 0.6
Incidents · Singapore Strait	1	3.4	0	—	2.5× / 0.4
Nav aids · Greenland Sea	1	3.1	0	—	5.0× / 0.2
Derelicts · Arabian Sea	1	3	0	—	1.3× / 0.8
Quakes · Bismarck Sea	1	3	0	—	2.5× / 0.4
Debris · Gulf of California	1	3	0	—	new / 0
Quakes · Gulf of California	1	3	0	—	1.7× / 0.6
Derelicts · Gulf of Mexico	1	3	0	—	1.3× / 0.8
Debris · Indian Ocean	1	3	0	—	new / 0
Derelicts · Japan Sea	1	3	0	—	new / 0
Quakes · Java Sea	1	3	0	—	new / 0
Icebergs · Kara Sea	1	3	0	—	0.4× / 2.6
Derelicts · Mediterranean Sea - Eastern Basin	1	3	0	—	2.5× / 0.4
Containers · North Atlantic Ocean	1	3	0	—	1.7× / 0.6
Containers · Timor Sea	1	3	0	—	new / 0
Derelicts · Timor Sea	1	3	0	—	new / 0
Derelicts · Tyrrhenian Sea	1	3	0	—	new / 0
Debris · Yellow Sea	1	3	0	—	new / 0
Missiles · Bay of Bengal	1	2.9	1	35	1.0× / 1
Other · Gulf of Mexico	1	2.8	1	2	new / 0
Other · Beaufort Sea	1	2.6	0	—	1.7× / 0.6
Piracy · Arabian Sea	1	2.4	1	2	new / 0
Exercises · Bering Sea	1	2.2	0	—	0.5× / 2.2
Piracy · Gulf of Guinea	1	1.9	1	1	1.7× / 0.6
Incidents · English Channel	1	1.6	0	—	5.0× / 0.2
Missiles · Gulf of Oman	1	1.6	1	1	new / 0
Exercises · Mediterranean Sea - Western Basin	1	1.5	1	1	new / 0
Exercises · Adriatic Sea	1	1.1	0	—	2.5× / 0.4
Icebergs · South Pacific Ocean	1	1	0	—	new / 0
Surveys · Aegean Sea	1	0.8	0	—	2.5× / 0.4

Cite: seahazards.com Sea Ledger, 2017-09, 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.