Pumice
Light volcanic rock floating in rafts after a submarine eruption; it can clog engine cooling intakes.
A submarine eruption can release enough pumice to form rafts that drift for months and cover hundreds of square kilometres. The 2012 eruption at Havre Seamount north of New Zealand produced one of the largest recorded, and pumice from the 2021 eruption of Fukutoku-Okanoba drifted to the coasts of Okinawa.
Pumice itself does not harm a hull, but it can block the seawater intakes that cool engines. Warnings report where rafts were seen and ask ships to navigate with caution.
What the archive shows
8 messages in this archive use “Pumice”, the earliest issued 2008-08-09 and the latest 2019-08-27. None of them is in force in the latest lists we collected. A hazard reported again and again counts once per message.
8 recorded messages form a small sample; the warning type breakdown should be read as individual records rather than a pattern.
Located messages that use it fall in 3 sea areas; the most frequent are South Pacific Ocean (3), North Pacific Ocean (1) and Bering Sea (1).
By warning series: HYDROPAC 6 and NAVAREA XII 2.
Messages using it, by year of issue
Where it appears · 3 sea areas
How it reads in recent messages
- HYDROPAC 2780/19 · Debris · South Pacific Ocean2019-08-27
SOUTH PACIFIC. TONGA. DNC 06. 1. 150 SQUARE KILOMETER PUMICE RAFT FROM VOLCANIC ACTIVITY ADRIFT REPORTED IN VICINITY 18-56S 176-21W AT 262350Z AUG…
150 square kilometer pumice raft from volcanic activity adrift reported in vicinity 18-56S 176-21W at… → - HYDROPAC 469/13 · Volcanic · South Pacific Ocean2013-02-16
WESTERN SOUTH PACIFIC. CHART 76030 DISCOLORED WATER AND PUMICE VICINITY 24-08.2S 177-43.4E AT 162014Z FEB.
Western South Pacific → - HYDROPAC 2834/12 · Volcanic2012-10-09
WESTERN SOUTH PACIFIC. CHART 76030 1. LARGE FIELD OF FLOATING PUMICE REPORTED IN AREA BETWEEN 24-00S 29-00S AND 177-00W 179-00E. 2. CANCEL HYDROPAC 2675/12.
Cancel HYDROPAC 2675/12 → - HYDROPAC 2675/12 · Volcanic2012-09-19
WESTERN SOUTH PACIFIC. CHART 76030 LARGE FIELD OF FLOATING PUMICE REPORTED IN AREA BETWEEN 30-00S 28-00S AND 178-00E 178-00W.
Western South Pacific → - HYDROPAC 2451/12 · Volcanic2012-08-27
WESTERN SOUTH PACIFIC. CANCEL HYDROPAC 2270/12 AND THIS MSG, PUMICE DISPERSED.
Cancel HYDROPAC 2270/12 and this msg, pumice dispersed → - HYDROPAC 2270/12 · Volcanic · South Pacific Ocean2012-08-10
WESTERN SOUTH PACIFIC. CHART 76030 105 BY 35 MILE FIELD OF FLOATING PUMICE REPORTED 70 MILES WEST OF RAOUL ISLAND (29-15S 177-55W).
Western South Pacific → - NAVAREA XII 122/09 · Volcanic · North Pacific Ocean2009-03-04
NGA CHART 502 (2ND ED). LARGE FIELD OF FLOATING PUMICE REPORTED VICINITY 18-00N 111-00W.
Nga chart 502 (2ND ed) → - NAVAREA XII 315/08 · Debris · Bering Sea2008-08-08
…ELEVATION OF 45,000 FEET. DUE TO POSSIBLE SUB-SURFACE ERUPTION NUMEROUS LARGE PUMICE RAFTS, VOLCANIC GASES OR ASH FALLOUT MAY CAUSE HAZARDS TO NAVIGATION. SEVEN MILE BERTH…
Nga chart 16486 (7TH ed) →
Often in the same message
Related terms
- Volcanic activity
- An erupting or restless volcano near or under the sea, with a keep-clear radius around it.
- Discoloured water
- Patches of unusually coloured sea — often a sign of a submarine volcano or of a shoal.
- Adrift
- Loose and moving with wind and current — a vessel, container, buoy, log or anything else no longer secured.
Warning types that use it
- Volcanic — Submarine eruptions, discoloured water, pumice rafts.
Counts cover the messages in this archive that use the term, recounted 2026-09-24; see coverage for what is collected and since when. Not for navigation — follow official NAVAREA and coastal broadcasts.