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The Effects of a Rising Sea Level on Maritime Limits and Boundaries

Published online by Cambridge University Press:  21 May 2009

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The sea level is rising. One of the causes of this phenomenon is the so-called ‘greenhouse effect’. This concept refers to the rising of the temperature of the atmosphere as a result of the increase of the concentration of carbon dioxide and several other gases in the atmosphere. One of the consequences of this rise in temperature is the melting of land ice, in particular glaciers and the ice-caps of Greenland and perhaps Antarctica. This melting water enters the ocean, which results, in combination with the expansion of sea water as a consequence of its higher temperature, in a rising of the sea level.

Copyright © T.M.C. Asser Press 1990

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1. Titus, J.G., ‘The Causes and Effects of Sea Level Rise, in Wind, H.G., ed., Impact of Sea Level Rise on Society (1987) pp. 104125Google Scholar; Schneider, S.H., ‘The Greenhouse Effect: Science and Policy, Science (1989) pp. 771781;Google ScholarMilliman, J.D., ‘Sea Levels: Past, Present and Future, Oceanus (1989) pp. 4044.Google Scholar

2. For an overview, see Nanda, V.P., ‘Trends in International Environmental Law’, California Western International Law Journal (19891990) pp. 187206Google Scholar.

3. Titus, loc cit. n. 1; Schneider, loc. cit. n. 1; Milliman, loc. cit. n. 1. It should be noted that earth crust movements may also lead to a relative dropping of the sea level. Also, as a result of biological processes (formation of coral) an atoll may keep pace with the rising sea level. These aspects will not be dealt with in this article.

4. Bardach, J.E., ‘Global Warming and the Coastal Zone’, Climatic Change (1989) pp. 117150Google Scholar. Rodgers-Miller, L. and Bardach, J.E., ‘In Face of a Rising Sea’, Ocean Yearbook (1988) pp. 177190.Google Scholar

5. ‘Greenhouse Effect Experts Predict Devastation in Asia’, International Herald Tribune, 31 December 1988/1 January 1989, p. 2; ‘The Greenhouse Effect. Say Goodbye to Kiribati, the Marshall Islands, Tokelau, TUvalu, the Great Barrier Reef’, Pacific Islands Monthly (April/May 1989) pp. 17–21. Specifically on the Maldives, : ‘Maldives Face Extinction’, The Indian Ocean Review (1988) no. 4, p. 11Google Scholar; ‘The Idyllic Islands of the Indian Ocean: The Maldives’, ibid., pp. 12–13.

6. Text in Environmental Policy and Law (1990) pp. 58–59. See also the Conference Statement of the International Conference on Global Warming and Climate Change: Perspectives from Developing Countries. New Delhi, February 21–23, 1989, 19 pp.

7. See the contributions in Wind, ed., op. cit. n. 1; Bardach, op. cit. n. 4.

8. The Times, March 6, 1989, p. 3.

9. Two papers have recently been published: Bird, E. and Prescott, V., ‘Rising Global Sea Levels and National Maritime Claims’, Marine Policy Reports (1989) pp. 177196Google Scholar. Freestone, D. and Pethick, J., ‘International Legal Implications of Coastal Adjustments under Sea Level Rise: Active or Passive Policy Responses?’, in UNEP/WMO/USACE/EPA/NOAA, Changing Climate and the Coast. Report to the Intergovernmental Panel on Climate Change from the Miami Conference on Adaptive Responses to Sea Level Rise and Other Impacts of Global Climate Change, vol. 1 (05 1990) pp. 237256.Google Scholar

10. UN Doc A/CONF. 62/122; ILM (1982) p. 1261.

11. Art. 308 of the Law of the Sea Convention provides that it will enter into force 12 months after the date of deposit of the sixtieth instrument of ratification or accession. In August 1990 the Convention had been ratified by 44 States.

12. See on this issue, Churchill, R.R. and Lowe, A.V., The Law of the Sea, 2nd edn. (1988) pp. 417.Google Scholar

13. Art. 5 of the Law of the Sea Convention (all further references in these footnotes to treaty articles are from the Law of the Sea Convention, unless expressly stated otherwise). On the baseline, see Churchill, and Lowe, , op. cit. n. 12, pp. 2650Google Scholar.

14. Art. 121, para. 1.

15. Art. 5.

16. On this issue, see: O'Connell, D.P., The International Law of the Sea, vol. I (1982) pp. 173183Google Scholar; Kapoor, D.C. and Kerr, A.J., A Guide to Maritime Boundary Delimitation (1986) pp. 1618.Google Scholar

17. Art. 6.

18. Art. 7.

19. Art. 7, para. 2. On the travaux préparatories and the significance of this provision, see Scovazzi, T., ‘La linea di base rette’, in Scovazzi, T., ed., La linea di base del mare territoriale (1986) pp. 120127Google Scholar.

20. Art. 9.

21. Art. 10.

22. Art. 46 defines an archipelago as ‘a group of islands, including parts of islands, interconnecting waters and other natural features which are so closely interrelated that such islands, waters and other natural features form an intrinsic geographical, economic and political entity, or which historically have been regarded as such’.

23. Art. 47.

24. Art. 8, para. 1.

25. Art. 2, para. 1. A limitation of this sovereignty (the right of innocent passage) may exist in some parts of maritime internal waters according to Art. 8, para. 2.

26. Art. 49.

27. Arts. 52–54.

28. Art. 3.

29. Art. 13.

30. Art. 2, para. 1.

31. Arts. 17–32.

32. Arts. 34–44.

33. Art. 33.

34. Art. 303, para. 2.

35. Art. 76, para. 1.

36. Art. 76, paras. 2–8.

37. Art. 77. Para. 4 of this article defines the natural resources of the continental shelf as the mineral and other non-living resources of the seabed and subsoil, as well as the living organisms belonging to sedentary species. In addition, the coastal State has jurisdiction with respect to marine scientific research (Art. 246 et seq.) and with respect to artificial islands and installations (Art. 80 jo. Art. 60).

38. Arts. 55 and 57. In the area up to 200 nautical miles, the EEZ and the continental shelf thus coincide.

39. Art. 56. The content and scope of these rights and jurisdiction of the coastal State, and of the rights of other States, are further defined in Arts. 58–73, 246 et seq. (marine scientific research) and Part XII (protection and preservation of the marine environment).

40. The concept of an ‘(exclusive) fisheries zone1 is not included in the Law of the Sea Convention. It has been developed in the past two decades in customary international law.

41. Art. 86.

42. Art. 87 et seq.

43. Part XI of the Law of the Sea Convention.

44. Churchill, and Lowe, , op. cit. n. 12, pp. 153163Google Scholar. O'Connell, , op. cit. n. 16, vol. II, chapters 16–18Google Scholar. Prescott, J.R.V., The Maritime Political Boundaries of the World (1985) pp. 81106.Google Scholar

45. Art. 15.

46. Arts. 74, para. 1 and 83, para. 1.

47. Kwiatkowska, B., ‘The ICJ Doctrine of Equitable Principles Applicable to Maritime Boundary Delimitation and its Impact on the International Law of the Sea’, in Bloed, A. and Dijk, P. van, eds., Forty Years International Court of Justice: Jurisdiction, Equity and Equality (1988) pp. 119158Google Scholar.

48. Arts. 74, para. 3 and 83, para. 3.

49. At present there exist approximately 100 maritime delimitation treaties which are in force. There exist 400 (potential) maritime boundaries. See Brown, E.D., Sea-Bed Energy and Mineral Resources and the Law of the Sea, vol. III (1986) pp. III. 4.19–33Google Scholar.

50. These conclusions apply mutatis mutandis to the contiguous zone and the (exclusive) fisheries zone. These two zones will not be mentioned separately in the following expositions.

50a. See Oxman, B.H., ‘The Third United Nations Conference on the Law of the Sea: the Ninth Session (1980)’, AJIL (1981) p. 230Google Scholar.

51. The consequence that as a result of this the outer limits of the continental shelf and the EEZ will be located separately should in itself not raise any objections: this is already the case with the continental shelf extending beyond 200 nautical miles. Should the outer limit recede, the seabed area involved would become included in the international seabed area.

Art. 76, para. 9 is a typical treaty provision and raises a number of questions. For example: what would be the consequences if the coastal State did not deposit the charts and relevant information? The drafters of this provision will probably not have thought about a rising sea level, and particularly not about significant changes in the location of the baseline.

52. For example, a concave or convex coastline, and the presence of other islands and low-tide elevations.

53. In the case of disappearing low-tide elevations there may only be effects when they were located at a distance of less than 12 nautical miles from the mainland or an island. Had they been located farther than 12 nautical miles, they would not have generated a territorial sea.

54. The area of a circle with a radius of 12 nautical miles is 1,548 square kilometers.

55. The exact extent of the loss depends on the location of the remaining baselines.

56. This is the area of a half circle with a radius of 200 nautical miles. Also in this case the exact extent of the loss depends on the location of the remaining baselines.

57. The area of a circle with a radius of 200 nautical miles is 431,014 square kilometers.

58. It is also possible that, as a result of sea level rise, the island becomes a low-tide elevation. Should it be located beyond 12 nautical miles from the mainland or an island, then the effect would be identical to the complete disappearance of an island. Should it be located within 12 nautical miles it will continue to serve as baseline.

59. van Dyke, J.M. and Brooks, R.A., ‘Uninhabited Islands: Their Impact on the Ownership of the Ocean's Resources’, Ocean Development and International Law Journal (1983) pp. 265300Google Scholar. van Dyke, J.M., Morgan, J. and Gurish, J., ‘The Exclusive Economic Zone of the Northwestern Hawaiian Islands: When do Uninhabited Islands Generate an EEZ?’, San Diego LR (1988) pp. 435494Google Scholar. Kwiatkowska, B. and Soons, A.H.A., ‘The Entitlement to Maritime Areas of Rocks which Cannot Sustain Human Habitation or Economic Life of Their Own’, 21 NYIL (1990) (in press)Google Scholar.

60. Art. 15.

61. Arts. 74 and 83.

62. In cases where a point was located on an island which through sea level rise has become a low-tide elevation, but on which no lighthouse or similar installation is present, it could be argued that a situation of ‘international recognition’ as referred to in Art. 7, para. 4, is involved.

63. Scovazzi, op. cit. n. 19.

64. Ibid. See also Prescott, , op. cit. n. 44, p. 70. This provision has not yet been applied in practice. Bangla Desh has established a baseline in 1972 using points located seaward of the lowwater lineGoogle Scholar.

65. Also in other respects the baselines and sea areas enclosed should still comply with the other criteria listed in Art. 7, para. 3.

66. See the contributions in Wind, ed., op. cit. n. 1.

67. On artificial islands, see Papadakis, N., The International Legal Regime of Artificial Islands (1977)Google Scholar; Soons, A.H.A., Artificial Islands and Installations in International Law, Occasional Paper No. 22, Law of the Sea Institute (University of Rhode Island), 07 1974, 30 pp.Google Scholar

68. Papadakis, , op. cit. n. 67, pp. 9197Google Scholar.

69. The same conclusion could arguably apply with respect to low-tide elevations, although this would not seem practicable (and would be very expensive).

70. This is totally different from artificially ‘extending’ a rock (Art. 121, para. 3) to become an island (Art. 121, para. 1); that situation will not be discussed here.

71. Iceland during 1985 reinforced the islet of Kolbeinsey, located approximately 60 nautical miles north of Iceland, which was about to disappear below sea level.

Japan has recently artificially preserved, at enormous costs (240 million US dollars), two rocks (Okino-tirishima, or Parece Vela) in the Western Pacific, hoping to preserve in this way approximately 400,000 square kilometers of EEZ. See Silverstein, A.L., ‘Okinotirishima: Artificial Preservation of a Speck of Sovereignty’, Brooklyn JIL (1990) pp. 409431Google Scholar.

72. It would also seem permissible to artificially conserve a low-tide elevation as referred to in Art. 7, para. 4.

73. The outer limit of the continental shelf has already been fixed as a result of the provisions of Art. 76, para. 9.

74. Bouchez, L.J., The Regime of Bays in International Law (1964) pp. 199302 (in particular p. 281)Google Scholar; O'Connell, , op. cit. n. 16, pp. 417438.Google Scholar

75. The coastal State will have to indicate expressly that it maintains the original limits. A problem could be caused by the fact that published charts may periodically indicate the changed lowwater line (baseline). Art. 16, para. 2, requires coastal States to deposit a copy of these charts with the Secretary-General of the United Nations. In such cases the coastal State should thus explicitly comment on the new low-water line with respect to its function (or rather, non-function) as a baseline.

75a. The Convention can be amended by normal procedure, involving a diplomatic Conference, but only after 10 years from its entry into force (Art. 312). It can also be amended (even before that date) by a simplified (written) procedure in accordance with Art. 313. These procedures do not apply to provisions relating to activities in the international seabed area.

76. Churchill, and Lowe, , op. cit. n. 12, pp. 153161Google Scholar; Prescott, , op. cit. n. 44, pp. 81106Google Scholar; O'Connell, op. cit. n. 16, vol. II, chapters 16–18.

77. Agreement between the Government of the Kingdom of the Netherlands and the Government of the United Kingdom of Great Britain and Northern Ireland relating to the Delimitation of the Continental Shelf under the North Sea between the two Countries, London, 6 October 1965; Trb. 1965 No. 191

78. An example is provided by the maritime delimitation treaty between Tonga and France (Wallis and Futuna), 11 January 1980. See The Law of the Sea. Maritime Boundary Agreements (1970–1984), United Nations (1987) pp. 273–275.

79. See n. 77 supra. From the debates in the Dutch Parliament it appears that it was the explicit intention of the Parties to determine the boundary definitively. See Bijl. Hand.T.K. 1965/1966, 8409, No. 3.

80. See Art. 62, para. 1, of the Vienna Convention on the Law of Treaties of 1969 (hereinafter referred to as the Vienna Convention). This provision can be considered as reflecting customary international law.

81. Art. 62, para. 2 of the Vienna Convention.

82. Kaikobad, K.H., ‘Some Observations on the Doctrine of Continuity and Finality of Boundaries’, BYIL (1983) pp. 119141Google Scholar. Wyrozumska, A., ‘Treaties Establishing Territorial Regimes’, Polish YIL (1986) pp. 261265Google Scholar.

83. Cf., Art. 61 of the Vienna Convention.

84. Kapoor, and Kerr, , op. cit. n. 16, pp. 89100Google Scholar. See also the literature referred to in nn. 47 and 76 supra.

85. See n. 82 supra.

86. ‘Maldives Face Extinction’, The Indian Ocean Review (December 1988) p. 11.

87. International Herald Tribune, 31 December 1988/1 January 1989, p. 2.

88. Shaw, N.M., International Law, 2nd edn. (1986) pp. 126130Google Scholar. Verzijl, J.H.W., International Law in Historical Perspective, vol. II (1969) pp. 62131Google Scholar.

89. Cf., however, the position of the Sovereign Order of Malta, as a precedent for retaining sui generis international legal personality by an entity no longer qualifying as a State: Shaw, , op. cit. n. 88, p. 152Google Scholar; Verzijl, , op. cit. n. 88, pp. 2832.Google Scholar

90. One could think of an entity, charged with the management of the sea areas involved for the benefit of the ‘population in exile’, as a sui generis subject of international law.