Sea Level Changes
in the Maldive Islands

We have chosen the Maldive Islands for our INQUA Commissional Research Project (ICRP) because we believe that this is an area where we can make a significant contribution to Sea Level Research. The reasons are four-folded:

(1) The Maldive Islands remain virtually unexplored with respect to sea level changes despite it potentials and strategic position.

(2) The Maldive Islands lie right in the deepest geoid hole in the world - some 100 m below the rotational ellipsoid. It is of the utmost importance to define the 20 ka regression limit in this area, because it would provide a direct clue to the possible deformation of the geoid relief. The same applies for successively younger sea level positions and the last interglacial level, too. In this area, we have ideal conditions to pinpoint this question.

(3) The Maldive Islands lie in an area where the dynamic sea surface is significantly lowered below the geoid level due to the extreme rate of evaporation. By investigating the Holocene sea level history in details, we may record changes in the evaporation rate. This also addresses a question of prime practical implications (global warming may lead to increased evaporation and, by that, to an increased lowering of the dynamic sea surface; i.e. a regional regression instead of a general transgression as often claimed).

(4) Fairbanks has proposed that the tropical region was significant cooler at 20 ka and that this acted to synchronize the two polar regions. Recent studies at Christmas Island show that this part of the tropics was significant cooler and without major variations at around the BÖ-YD oscillations. In the Maldive Islands, there are ideal possibilities to test these findings.

Anticipated results:

(1) Solving the burning sea level question of the long-term stability of the geoid relief. Establishing the 20 ka sea level position.
Subsequent transgressional positions and the last interglacial level.

(2) Reconstructing the Holocene sea level history in details.
Documenting decadal signals.
Tracing possible evaporation effects on dynamic sea surface.
Reconstructing ocean circulation changes.

(3) Answering the question on tropical climate at 20 ka and around 12 ka.
Dating past sea level positions
Tracing the corresponding climatic conditions
Modeling the controlling global system

Confirmed international participation:

Nils-Axel Mörner


coordinator, on-shore geology


Jacques Laborel France reef bioecology & diving M

Richard Fairbanks


dating, general expert


Peter Ramsay

South Africa

off-shore geophysics & diving


Colin Woodroffe


micro-atoll sampling


Michael Tooley


paleoenvironmental studies


Douglas Grant


on-shore geology


Roger McLean


micro-atoll sampling


Chas Anderson

the Maldives

submarine notches


Bjarne Lembke


medical doctor, diving


Young scientists:

Mohamed Ali

the Maldives

local leader, island formation


Sue Dawson


micropaleontology, tsunamis


Shahidul Islam Bangladesh lagoonal core analysis M
Caroline Rufin France geomorphology W
V.J. Loveson India remote sensing M
Researcher-1-3 South Africa assistance to Ramsay MW
Researcher-4-6 USA assistance to Fairbanks MW
Researcher-7 Sri Lanka project participant MW
others to be added regional students from the region MW
Local Male representatives
Ismail Shafeeu the Maldives Minister, environment M
Mohamed Khaleel the Maldives Director of Environment M
Hussain Naeem the Maldives environmental assistant M
Hussan Maniku the Maldives diver, local specialist M
Sea Explorers the Maldives diving MW
Omar Naseer the Maldives submarine (Whale Submarine) M
others to be added the Maldives local input MW




inspection and site selection

Field expedition-1

lagoonal coring, diving

on-shore and near-shore studies


dating, sediment core analyses


Field expedition-2

off-shore geophysics, coring, diving

island studies, micro-atoll samples


interpretation and analyses


Field expedition-3

coral core drillings

core sampling


core sample analyses

Workshop integration

data presentation and


results and conclusions

2003 Analyses summary and conclusions
presentation at INQUA in Reno


(1) project workshop-1 on the Maldives in 2000

(2) training course (TP-2) in 2001 or 2002

(3) project workshop-2 on the Maldives in 2001

(4) concluding project meeting in 2002

(5) report at INQUA in Reno in 2003

Relations to other international projects:

(1) ODP Sea Level Project (a direct link via Fairbanks)

(2) IGCP-437 new sea level project

(3) PAGES-LOIZC project

(4) INQUA Commission on Paleoclimate

(5) The Alliance of Small Island States

(6) IPCC (the sea level part)


We will continually report on the progress of the project by updating this entry in our homepage. You are also invited to communicate directly to anyone of the team members and especially the co-ordinator (Email:

Nils-Axel Mörner

Selected references:

Agassiz, A., 1903. The coral reefs of the Maldives. Mem. Mus. Comp. Zool. Harvard Coll., 29, 1-168.

Ali, M., 2000. Reef island gemorphology: Formation, development, and perspectives of islands in Eta atoll, South Maalhosmadulu, the Maldives. Ph.D.-thesis, Univ. S. Wales, 296 pp.
Anderson, R.C., 1998. Submarine topography of Maldivian atolls suggests a sea level of 130 m below present at the last glaciation maximum. Coral Refs, 17 (4), 339-341.

Davis, P.S., Stoddart, D.R. & Sigeo, D.C., 1971. Reef forms of Addu Atoll, Maldive Islands. Symp. Zool. Soc. London, 28, 217-259.

Gardiner, J.S., 1902. The formation of the Maldives. Geogr. J., 19, 277-301.

Mörner, N.-A., 2000. Sea Level Changes and Coastal Dynamics in the Indian Ocean. Integrated Coastal Zone Management, , p. 17-20. ICG Publ. Ltd

ODP, 1990. Leg. 115, Hole 714A and 716B (the Maldives).

Prudy, E.G., 1981. Evolution of the Maldive atolls, Indian Ocean. Proc 4th Int. Coaral Reef Symp, 1, 659.

Woodroffe, C.D., 1992. Morphology and evolution of reef islands in the Maldives. Proc. 7th Int. Coral Reef Symp, Gaum, 1992, 2, 1217-1226.

Purdy, E.G. & Beertrand, G.T., 1992. Atoll carbonate platform development in the Maldives, Indian Ocean. AAPG, Studies in Geology, 34, 1-56.

Report from the 1st Expedition of the Maldives Project
From October 7 to October 28, we run the 1st Expedition of the Maldives Project in collaboration with the Ministry of Environment in Male.
5 days research in Male and neighbouring areas
10 days boat-expedition to the Goidhoo—Baa Atolls
7 days research in Male and neighbouring areas
We note the following main results:
The recording of Last Interglacial beds (for the first time)
The collection of 7 sediment cores of lagoonal mud (for the first time)
The recording of notches and caves in pre-Holocene reefs
The identification of different Holocene sea level stands
Sampling of soil sections and two mangrove swamps
The recording of a total absence of any recent sea level rise
The recording of a young (last 20 years) sea level fall
The documentation of present coral reef status (post-bleaching)
Establishment of a fine local network for coming studies

WE DID IT: found Last Ingerglacial rocks, took lagoonal sediment cores, collected several samples for dating sea level changes, and finally recorded a total absence of traces of a present sea level rise — on the contrary a significant regression.
The boat of the Ministry with the team: Niklas, the crew, Sue, Francois, Caroline, Shahidul, Bjarne and Dago. Motto: "je planche — donc, je sui" (neo-Cartesius, 2000).

VILIGILI ISLAND: multiple sea level indicators.

VILIGILI ISLAND: the Last Interglacial corals and beachrock in the foreground and the lonely tree on the rockshore (this tree has remained in this position for some 40 years and was a marker for the prisoners coming and leaving this island).

FOHODOO ISLAND: beachrock cut into a rock cut platform at a slightly higher sea level and today’s bioerosion not reaching up to this level, hence indicating a recent regression (like in so many other islands visited).

SHAHIDUL’S SWAMP, GOIDHOO: a marine embayment became successively more shallow and turned into a mangrove swamp which was later transformed into an alluvial basin.
Informant: Nils-Axel Mörner