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Demise of the Maldives: Greatly Exaggerated?
Volume 7, Number 3: 21 January 2004

The Maldives of the central Indian Ocean consist of some 1200 small islands grouped in about twenty larger atolls that rise only one to two meters above local mean sea level.  Hence, it is not surprising that the IPCC and the legions of climate alarmists who take their cue from the publications of that organization have singled them out for special notoriety by predicting their imminent inundation by the rising sea level that they say will result from CO2-induced global warming.  Real-world observations, on the other hand, suggest that the not-so-precarious islands still have a long terrestrial future in front of them, and that the dire prognostications of their impending submergence lack a sound scientific backing.

Writing in the journal Global and Planetary Change, Morner et al. (2004) describe how the INQUA Commission on Sea Level Changes and Coastal Evolution initiated a special research project "to decode the history of the Maldives, record the past sea level changes and understand the present-to-future prospect of the islands (INQUA, 2000; Tooley, 2000)."  In reporting the results of this project, they begin by presenting a sea level curve for the past 5000 years that depicts the sea level "oscillating with four levels above the present level: +1.1-1.2 m at 3900 BP, +0.1-0.2 m at 2700 BP, +0.5-0.6 m at 1000-800 BP and +0.2-0.3 m at AD 1900-1970."  In commenting on these observations, Morner et al. note that "the islands were well inhabited by 1500-1300 BP" and, therefore, that their inhabitants had to have survived "a higher sea level of some 40-50 cm at around 1000-800 BP."

With respect to the present, the trio of scientists report in their study of the coastal dynamics and geomorphology of the islands' shores that they "were unable to detect any traces of a recent sea level rise."  In fact, they say they "found quite clear morphological indications of a recent fall in sea level."  Based on (1) general island morphology, (2) sailing routes in the Vavu Atoll, (3) the "reef woman" [a coral-encrusted skeleton] at Lhosfushi, and (4) the morphology of the "Queen's Bath" Lake on Hithadhoo, they conclude that "some 100 to 30 years ago, sea level was 20-30 cm higher than it is today," and that "in the 1970s to early 1980s, sea level experienced a general fall of the order of 20-30 cm."

In commenting on the significance of this finding, Morner et al. say that "in the IPCC scenarios, the Maldives were condemned to disappear in the sea in the near future (e.g. Hoffman et al., 1983; IPCC, 2001)," but that their own "documentation of actual field evidence contradicts this hypothesis."  In this context, however, they note that tide gauge data have been cited by Singh et al. (2001) in support of an on-going rise in mean sea level in the vicinity of the Maldives; but they say that such data "do not provide simple and straight-forward measures of regional eustatic sea level" and that "they are often dominated by the effects of local compaction and local loading subsidence," whereas their "multiple morphological and sedimentological records appear more reliable and conclusive," noting also that "satellite altimetry does not record any significant rise in global sea level in the last decades."  In addition, they note that "available tide gauge records, now extending from 1990 to 2002, were re-examined," with the data indicating "a total absence of any rising secular trend."

So why did the sea level decline so significantly in the vicinity of the Maldives sometime within the past three decades or so?  Morner et al. say that in the central Indian Ocean "eustatic sea level lies well below the geoid surface because of an exceptionally high rate of evaporation (Morner, 2000)."  Hence, they suggest that "the sea level regression recorded in [their] observational data is the effect of increased evaporation," which they say "fits with an increase of the NE-monsoon in the last decades as recorded in so many islands," as well as with the findings of Pfeiffer et al. (2001) that suggest a change in monsoonal circulation at about the same time.

As for the years and decades ahead, Morner et al. suggest that if the evaporation rate increases further, "sea level will fall regionally."  Hence, they conclude "there seems no longer to be any reasons to condemn the Maldives to become flooded in the near future."

Sherwood, Keith and Craig Idso

References
Hoffman, J.S., Keyes, D. and Titus, J.G.  1983.  Projecting Future Sea Level Rise.  U.S. Environmental Protection Agency, Washington DC.

INQUA.  2000.  Homepage of the Commission on Sea Level Changes and Coastal Evolution, www.pog.su.se/sea.  Sea Level Changes, News and Views, The Maldives Project.

IPCC.  2001.  Climate Change 2001.  Cambridge University Press, Cambridge, UK.

Morner, N.-A.  2000.  Sea level changes in the Indian Ocean.  In: Integrated Coastal Zone Management, Launch Ed.  IPC Publ., pp. 17-20.

Morner, N.-A., Tooley, M. and Possnert, G.  2004.  New perspectives for the future of the Maldives.  Global and Planetary Change 40: 177-182.

Pfeiffer, M., Dullo, C. and Eisenhauer, A.  2001.  Indian Ocean reef corals: evidence for secular changes in monsoon circulation?  In: Ruth, S. and Ruggenberg, A. (Eds.), 2001 Margins Meeting Schrift. Deutschen Geol. Gesellschaft, Vol. 14: 151-152.

Singh, O.P., Ali Khan, T.M., Aktar, F. and Sarker, M.A.  2001.  Recent sea level and sea surface temperature change along the Maldives coast.  Marine Geodesy 24: 209-218.

Tooley, M.  2000.  Sea level?  Quaternary Perspectives 11: 1.