Sea Ledger, April 2016

2016-04-01 to 2016-04-30 · archive

issued: 594
warning-days in force: 10,494
in force at month end: 367
sea × type cells: 239

baseline: same month, previous 5 years (2015-04, 2014-04, 2013-04, 2012-04, 2011-04)

By type

type	issued	warning-days	in force at end
Incidents	128	977.2	47
Exercises	105	1,248.6	28
Nav aids	63	2,564.6	96
Quakes	56	158.3	3
Cable ops	43	1,161.8	42
Surveys	41	1,657	57
Icebergs	38	57.3	3
Missiles	34	201.3	4
Derelicts	21	128.4	3
Other	18	469	17
Piracy	12	58	2
Spills	10	177	5
Restricted	8	405.6	15
Ordnance	7	118.9	8
Wrecks	4	822.7	28
Debris	4	12	0
Containers	2	6	0
War risk	0	60	2
Volcanic	0	120	4
Structures	0	90	3

By sea and type · 200 cells, most issued first

cell	issued	warning-days	at end	longest d	vs 5 y
Incidents · Mediterranean Sea - Eastern Basinsurge	21	138	9	34	2.3× / 9
Icebergs · North Atlantic Oceansurge	21	24	2	31	2.7× / 7.8
Incidents · North Pacific Ocean	20	92.3	3	72	0.8× / 24.4
Exercises · North Pacific Ocean	17	155.5	3	65	1.3× / 13.4
Incidents · South China Sea	17	96.1	4	60	1.4× / 12.6
Exercises · South Pacific Oceansurge	16	61.1	1	28	4.2× / 3.8
Incidents · North Atlantic Ocean	15	230.8	8	47	1.0× / 15
Exercises · Yellow Sea	14	76.5	3	38	1.6× / 9
Quakes · North Pacific Ocean	14	38	1	20	1.4× / 10.2
Surveys · South Atlantic Ocean	12	196.6	6	240	1.9× / 6.4
Nav aids · North Atlantic Oceansurgelong running	11	220.9	12	1,074	2.8× / 4
Exercises · Black Sea	11	74.1	1	32	1.2× / 9.4
Quakes · Coral Seasurge	11	26.9	2	27	3.9× / 2.8
Nav aids · Coral Seasurgelong running	10	102	4	743	3.1× / 3.2
Nav aids · North Sea	9	150.1	7	256	0.9× / 10.4
Incidents · South Pacific Ocean	9	71	3	35	1.1× / 8
Exercises · South Atlantic Ocean	9	63.7	0	—	1.2× / 7.6
Incidents · South Atlantic Ocean	9	44.8	3	77	1.3× / 6.8
Piracy · Gulf of Guineasurge	9	35.5	1	29	7.5× / 1.2
Quakes · South Pacific Ocean	9	27	0	—	0.7× / 12.4
Icebergs · South Atlantic Oceansurge	9	24.2	1	32	4.1× / 2.2
Icebergs · Labrador Sea	8	9.1	0	—	0.7× / 12.4
Incidents · Gulf of Mexicosurge	7	56.2	5	25	2.7× / 2.6
Missiles · South Pacific Oceansurge	7	20.8	0	—	2.9× / 2.4
Surveys · Arabian Seasurge	6	158.1	7	65	30× / 0.2
Missiles · Barentsz Sea	6	42.8	1	34	1.9× / 3.2
Surveys · Mediterranean Sea - Eastern Basinsurge	6	33.9	1	51	5.0× / 1.2
Cable ops · Barentsz Seasurge	6	29.4	4	15	7.5× / 0.8
Missiles · North Atlantic Ocean	6	20.4	0	—	1.2× / 5
Quakes · Eastern China Seasurge	6	18	0	—	15× / 0.4
Derelicts · Indian Ocean	6	18	0	—	1.1× / 5.6
Nav aids · Gulf of Mexicosurgelong running	5	201.7	8	805	4.2× / 1.2
Cable ops · Gulf of Mexicosurge	5	90.5	3	295	3.1× / 1.6
Ordnance · Sea of Azovnew	5	76.4	5	82	new / 0
Nav aids · South Atlantic Ocean	4	379.9	14	198	0.6× / 7.2
Incidents · Caribbean Sea	4	125.1	4	49	1.3× / 3
Cable ops · Arabian Sea	4	99	4	86	1.7× / 2.4
Surveys · Bay of Bengalsurge	4	70	2	37	3.3× / 1.2
Exercises · Philippine Sea	4	68.7	2	34	1.2× / 3.4
Nav aids · Arabian Seasurgelong running	4	67.5	2	369	3.3× / 1.2
Exercises · Arabian Sea	4	55.5	1	45	0.6× / 6.6
Exercises · North Atlantic Ocean	4	35.3	1	93	0.7× / 5.6
Cable ops · Norwegian Seasurge	4	16.3	4	6	3.3× / 1.2
Incidents · Indian Ocean	4	15.1	1	30	0.4× / 9.4
Missiles · Baffin Baynew	4	8.6	0	—	new / 0
Incidents · Coral Sea	4	6.6	0	—	1.1× / 3.8
Surveys · North Atlantic Oceanlong running	3	159.3	6	697	1.5× / 2
Restricted · Black Seanewlong running	3	113.4	4	1,060	new / 0
Exercises · South China Sea	3	84.8	2	34	1.4× / 2.2
Nav aids · Bass Straitsurgelong running	3	67	2	1,125	5.0× / 0.6
Spills · Gulf of Mexico	3	50	3	40	0.8× / 3.6
Nav aids · Gulf of Sueznew	3	44.7	2	40	new / 0
Nav aids · Inner Seas off the West Coast of Scotland	3	41.2	1	297	0.8× / 3.8
Cable ops · North Sea	3	37.4	1	49	1.1× / 2.6
Derelicts · South Pacific Oceansurgelong running	3	36.3	1	1,403	2.1× / 1.4
Missiles · Black Seasurge	3	35.7	2	30	3.0× / 1
Cable ops · South Atlantic Ocean	3	24	0	—	0.2× / 16.4
Derelicts · North Atlantic Ocean	3	14.3	0	—	0.7× / 4.6
Missiles · North Pacific Ocean	3	13.7	0	—	0.5× / 6.6
Other · Mediterranean Sea - Eastern Basin	3	11.9	1	16	1.5× / 2
Quakes · Indian Ocean	3	9	0	—	0.6× / 5.4
Debris · North Atlantic Oceansurge	3	9	0	—	2.5× / 1.2
Quakes · Philippine Sea	3	9	0	—	1.9× / 1.6
Exercises · Mediterranean Sea - Eastern Basin	3	6.4	1	10	0.5× / 5.6
Derelicts · English Channelnew	3	4.4	0	—	new / 0
Incidents · Arafura Seasurge	3	0.5	0	—	15× / 0.2
Surveys · Persian Gulf	2	110.3	4	106	10× / 0.2
Other · South China Sealong running	2	81.8	3	521	2.0× / 1
Ordnance · North Sea	2	42.5	3	235	10× / 0.2
Exercises · Bay of Bengal	2	37.9	0	—	0.2× / 8.4
Cable ops · North Atlantic Ocean	2	33.8	2	55	0.4× / 5.6
Spills · North Atlantic Ocean	2	30	0	—	10× / 0.2
Cable ops · Sea of Marmaranew	2	25.5	1	25	new / 0
Spills · North Pacific Ocean	2	23	1	38	2.0× / 1
Cable ops · South China Sea	2	20.9	2	19	0.8× / 2.6
Nav aids · South Pacific Ocean	2	20.2	2	10	5.0× / 0.4
Exercises · Gulf of Mexico	2	18.3	0	—	1.4× / 1.4
Piracy · Celebes Seanew	2	16.6	0	—	new / 0
Exercises · Baltic Sea	2	13.1	0	—	0.8× / 2.6
Missiles · Bay of Bengal	2	10.7	0	—	1.4× / 1.4
Cable ops · Bass Straitnew	2	10.1	0	—	new / 0
Quakes · Banda Sea	2	6	0	—	2.5× / 0.8
Quakes · Bering Sea	2	6	0	—	10× / 0.2
Containers · Norwegian Seanew	2	6	0	—	new / 0
Quakes · South Atlantic Ocean	2	6	0	—	1.1× / 1.8
Derelicts · Laccadive Sea	2	4.4	0	—	5.0× / 0.4
Restricted · Sea of Azovnew	2	4.2	1	123	new / 0
Other · English Channel	2	3.9	1	3	5.0× / 0.4
Exercises · Norwegian Seanew	2	2.8	0	—	new / 0
Exercises · Caribbean Sea	2	1.3	0	—	2.0× / 1
Surveys · South Pacific Ocean	2	1.3	0	—	3.3× / 0.6
Nav aids · Gulf of Alaska	2	0.5	0	—	1.3× / 1.6
Exercises · Aegean Sea	1	328.6	10	124	1.3× / 0.8
Nav aids · Caribbean Sealong running	1	240.5	9	810	new / 0
Restricted · North Sealong running	1	239.7	8	1,500	5.0× / 0.2
Cable ops · Bay of Bengal	1	201.7	6	121	0.7× / 1.4
Wrecks · Arabian Sealong running	1	155.4	6	943	0.8× / 1.2
Cable ops · Andaman or Burma Sea	1	101.6	2	70	5.0× / 0.2
Nav aids · Celtic Sealong running	1	100.8	3	1,283	0.8× / 1.2
Cable ops · Mediterranean Sea - Eastern Basin	1	91.9	3	66	0.4× / 2.4
Exercises · Ionian Sea	1	90	3	119	5.0× / 0.2
Nav aids · Mediterranean Sea - Western Basin	1	61.1	2	44	2.5× / 0.4
Nav aids · Laccadive Sea	1	60.9	2	137	1.3× / 0.8
Cable ops · Indian Ocean	1	59.5	2	79	5.0× / 0.2
Surveys · Caribbean Sea	1	57.2	2	183	2.5× / 0.4
Cable ops · Caribbean Sea	1	56.6	2	105	new / 0
Wrecks · Caribbean Sealong running	1	54.4	2	564	1.7× / 0.6
Nav aids · English Channel	1	35.2	1	67	0.4× / 2.4
Wrecks · Kara Sealong running	1	35	1	541	new / 0
Other · Caribbean Sealong running	1	32.1	1	466	1.3× / 0.8
Exercises · Laccadive Sea	1	31.6	0	—	0.4× / 2.6
Other · Inner Seas off the West Coast of Scotland	1	30	1	56	5.0× / 0.2
Nav aids · Mediterranean Sea - Eastern Basinlong running	1	30	1	484	2.5× / 0.4
Other · Bay of Bengal	1	29.4	1	29	2.5× / 0.4
Other · Sea of Azov	1	29	1	28	new / 0
Cable ops · Eastern China Sea	1	26.9	0	—	1.7× / 0.6
Cable ops · Red Sea	1	25.4	0	—	new / 0
Surveys · Laccadive Sea	1	24.7	0	—	5.0× / 0.2
Surveys · North Sea	1	23	1	48	1.7× / 0.6
Other · North Sea	1	21.5	1	21	0.6× / 1.6
Exercises · Sea of Okhotsk	1	19.9	0	—	new / 0
Wrecks · Great Australian Bight	1	17.7	1	17	new / 0
Other · Celtic Sea	1	17.5	0	—	new / 0
Cable ops · Mediterranean Sea - Western Basin	1	17.5	1	17	1.0× / 1
Other · Sea of Okhotsk	1	16.4	1	16	new / 0
Incidents · Mozambique Channel	1	15.8	0	—	0.5× / 2.2
Surveys · Gulf of Suez	1	15.4	1	40	1.7× / 0.6
Incidents · Japan Sea	1	15.1	1	36	2.5× / 0.4
Spills · Bering Sea	1	14	0	—	new / 0
Spills · Gulf of Alaska	1	14	0	—	5.0× / 0.2
Spills · South Pacific Ocean	1	14	0	—	new / 0
Cable ops · Strait of Gibraltar	1	13.8	0	—	new / 0
Derelicts · Bay of Bengal	1	11.1	1	33	5.0× / 0.2
Restricted · Persian Gulf	1	10.6	1	10	new / 0
Incidents · Tyrrhenian Sea	1	9.5	1	9	1.3× / 0.8
Incidents · Southern Ocean	1	9.2	1	9	2.5× / 0.4
Surveys · English Channel	1	8.4	1	8	new / 0
Exercises · Andaman or Burma Sea	1	7.7	0	—	0.6× / 1.8
Restricted · Barentsz Sea	1	7.7	0	—	new / 0
Exercises · Adriatic Sea	1	7.1	0	—	1.7× / 0.6
Missiles · Japan Sea	1	7	0	—	0.6× / 1.6
Incidents · Laccadive Sea	1	7	1	7	2.5× / 0.4
Cable ops · Irish Sea and St. George's Channel	1	6.3	0	—	2.5× / 0.4
Missiles · Indian Ocean	1	6.1	0	—	1.3× / 0.8
Incidents · Bay of Bengal	1	6	0	—	1.7× / 0.6
Piracy · Gulf of Aden	1	5.9	1	5	0.6× / 1.6
Other · Mozambique Channel	1	5.6	0	—	new / 0
Missiles · Laccadive Sea	1	5.5	0	—	1.0× / 1
Incidents · Gulf of Guinea	1	4.8	0	—	new / 0
Other · North Pacific Ocean	1	4.1	0	—	0.8× / 1.2
Quakes · Molukka Sea	1	3.4	0	—	1.7× / 0.6
Incidents · Philippine Sea	1	3.1	1	3	0.3× / 3
Quakes · Bismarck Sea	1	3	0	—	1.3× / 0.8
Derelicts · Caribbean Sea	1	3	0	—	1.3× / 0.8
Exercises · Coral Sea	1	3	0	—	1.0× / 1
Quakes · North Atlantic Ocean	1	3	0	—	5.0× / 0.2
Debris · North Pacific Ocean	1	3	0	—	new / 0
Other · Norwegian Sea	1	3	0	—	new / 0
Quakes · Sulu Sea	1	3	0	—	new / 0
Derelicts · Yellow Sea	1	3	0	—	new / 0
Incidents · Arabian Sea	1	2.8	0	—	0.4× / 2.4
Exercises · Mediterranean Sea - Western Basin	1	2.4	0	—	new / 0
Exercises · Indian Ocean	1	2.1	0	—	0.8× / 1.2
Surveys · Celtic Sea	1	2	0	—	1.3× / 0.8
Incidents · Aegean Sea	1	1.8	1	1	new / 0
Incidents · Alboran Sea	1	1.4	1	1	new / 0
Nav aids · Andaman or Burma Sea	1	1.2	0	—	1.7× / 0.6
Exercises · Barentsz Sea	1	1.2	0	—	5.0× / 0.2
Derelicts · Arafura Sea	1	0.4	0	—	1.0× / 1
Incidents · Java Sea	1	0.4	0	—	2.5× / 0.4
Other · Philippine Sea	1	0.4	0	—	5.0× / 0.2
Incidents · Timor Sea	1	0.3	0	—	5.0× / 0.2
Incidents · Davis Strait	1	0.1	0	—	1.0× / 1
Incidents · Great Australian Bight	1	0	0	—	0.8× / 1.2
Surveys · Beaufort Sealong running	0	240	8	2,089	— / 0
Surveys · Arctic Oceanlong running	0	180	6	2,014	— / 0
Nav aids · Bay of Bengal	0	150	5	208	0.0× / 1
Surveys · Davis Strait	0	120	4	216	— / 0
Nav aids · Indian Oceanlong running	0	90	3	801	0.0× / 0.6
Surveys · Indian Ocean	0	90	3	116	0.0× / 1.2
Nav aids · North Pacific Oceanlong running	0	90	3	457	0.0× / 2
Wrecks · Solomon Sealong running	0	90	3	417	— / 0
Wrecks · South China Sealong running	0	90	3	719	0.0× / 0.2
Nav aids · Singapore Strait	0	69.4	2	352	— / 0
Nav aids · Kara Sealong running	0	68.4	2	1,697	— / 0
Wrecks · English Channel	0	60	2	242	0.0× / 0.2
Nav aids · Great Australian Bightlong running	0	60	2	423	0.0× / 0.4
Wrecks · Irish Sea and St. George's Channel	0	60	2	316	— / 0
Nav aids · Malacca Strait	0	60	2	187	— / 0
War risk · Mediterranean Sea - Eastern Basinlong running	0	60	2	1,802	— / 0
Volcanic · Philippine Sealong running	0	60	2	1,462	0.0× / 0.4
Nav aids · Sea of Okhotsklong running	0	60	2	1,593	— / 0
Cable ops · Sulu Sea	0	60	2	42	— / 0
Surveys · The Northwestern Passageslong running	0	60	2	1,363	— / 0
Missiles · Aegean Sea	0	30	1	120	— / 0
Nav aids · Alboran Sea	0	30	1	39	— / 0
Wrecks · Andaman or Burma Sea	0	30	1	212	— / 0
Cable ops · Arafura Sea	0	30	1	125	— / 0
Surveys · Bering Sea	0	30	1	299	— / 0
Other · Black Sea	0	30	1	118	— / 0

Cite: seahazards.com Sea Ledger, 2016-04, 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.