TiefseeDeep-sea programme

Deep-sea research / one ship, two vehicles / since 1986

Eleventhousandmetres down.

Five zones, a hundred and twenty-eight standing stations, and everything we find published inside a year of the ship docking.

Go down

0 – 200m

Sunlit

Epipelagic

Everything that photosynthesises, and almost everything anybody has ever photographed. We spend as little time here as the ship can manage, because it is already the best-described water on the planet.

1 %
Of ocean volume
96 %
Of published papers
18
Stations held

200 – 1 000m

Twilight

Mesopelagic

The layer that moves. Every night the largest migration on Earth rises through it and every dawn it sinks again, and the carbon it carries down is the single biggest number nobody can pin within a factor of two.

20 %
Of ocean volume
×2
Uncertainty on carbon flux
31
Stations held

1 000 – 4 000m

Midnight

Bathypelagic

No sunlight at all, and more light than you would expect: something like nine in ten animals down here make their own. Our two vehicles are painted matte black for exactly this reason.

≈ 90 %
Of animals bioluminescent
4 °C
Water temperature
26
Stations held

4 000 – 6 000m

Abyss

Abyssopelagic

Flat, cold and enormous: most of the sea floor on the planet is this, a plain of soft sediment that takes a thousand years to lay down a centimetre. Also where the nodule licences are.

1 cm
Sediment per 1 000 years
600 bar
At 6 000 m
44
Stations held

6 000 – 11 000m

Trench

Hadopelagic

Twenty-seven separate trenches, each one effectively an island: too deep for anything to cross between them. The last full-depth dive from this programme was in 2024 and it lasted eleven hours.

27
Trench systems
11 h
Longest dive
9
Stations held

Below a thousand metres there is no seasonality, no daylight and almost no data. Four fifths of the living space on this planet is down there and we have looked at a fraction of one per cent of it with our own eyes.

Tiefsee is a consortium programme: one ship, two crewed and uncrewed vehicles, six landers, and a hundred and twenty-eight stations that have been reoccupied on the same coordinates since 1986.

The oldest of those time-series is now forty years long, which is the only reason anybody can say anything at all about whether the abyssal plain is changing.

128

Stations held

11 034

Metres, deepest dive

16 000

Hours of seabed video, public

12

Months, maximum embargo

What goes down

One ship, five kinds of vehicle. The landers are the cheapest and have done the most work.

  1. Research vesselRV Meridian78 m, ice class 1B200932 crew, 24 scientists
  2. Remote vehicleNautilus 6000Rated 6 000 m2018Fibre tether, 8 km
  3. Autonomous gliderKelpieRated 1 000 m202190-day endurance
  4. Crewed submersibleVollmer IIRated 11 000 m2023Three seats
  5. Free-fall landersLander A – FRated 11 000 m2016 – 2024Six units, ballast release

We have better maps of Mars. Mars does not have four kilometres of water on top of it.

Dr Salla Vainio, chief scientist

Recent cruises

Every one of these has its full dataset online. The number is the cruise, not the year.

  1. ME-114Iberian Abyssal Plain202631 daysSediment cores, 44 stations
  2. ME-112Charlie-Gibbs Fracture202624 daysMidwater trawls and imaging
  3. ME-109Puerto Rico Trench202538 daysFull-depth, Vollmer II × 6
  4. ME-106Rockall Trough202519 daysTime-series, station R7
  5. ME-103Azores, Menez Gwen202522 daysVent chemistry
  6. ME-098Kermadec Trench202446 daysFull-depth, 11 h dive
  7. ME-094Bay of Biscay202416 daysGlider recovery, Kelpie × 3
  8. ME-089Mid-Atlantic Ridge, 45° N202333 daysVent fauna, first survey
  9. ME-085Porcupine Abyssal Plain202328 daysTime-series, 30th year
  10. ME-081Greenland Basin202225 daysUnder-ice, autonomous only

What we do with it

Publication
Every dataset is public within twelve months of the ship docking. No exceptions have been granted since 2011.
Imagery
All video and stills are CC BY. Sixteen thousand hours of it, indexed by station.
Berths
Four berths on every cruise are held for early-career scientists from outside the consortium.
Mining
The programme surveys licence areas and publishes what it finds. It does not consult for licence holders.

Berths, data, collaboration

A shore office and two turns

  • Kiel

    Shore office and archive

    Schwentinestrasse 12, 24149

    54.33 N 10.14 E

  • Las Palmas

    Refit and northern turn

    Muelle Grande, 35008

    28.14 N 15.42 W

  • Walvis Bay

    Southern turn

    Third Street East, 13013

    22.96 S 14.51 E

  • At sea

    Two hundred days a year

    Wherever the transect is

    Iridium, when it feels like it

The ship is at sea about two hundred days a year and the shore office answers within a week, faster if the request is for data that should already be public.