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The Mediterranean as a maritime trade route
Ocean Management, 3 (1978) 179--189 © Elsevier Scientific Publishing Company, Amsterdam -- Printed in The Netherlands
T h e M e d i t e r r a n e a n as a M a r i t i m e T r a d e R o u t e J. Qu~guiner Administrateur O~n~ral des Affaires Maritimes, Paris (France)
ABSTRACT Ever since earliest antiquity, the Mediterranean has served as a channel for trade both between the countries bordering upon it and later, with the refinement of navigation techniques, with the other regions of the world. With the opening of the Suez Canal, it became a crossroad for shipping trade between North and South and between East and West. Especially vulnerable because it is semi-enclosed, the Mediterranean is threatened both by the nature of the cargoes being transported and by the density of maritime traffic. In order to safeguard the Mediterranean, special attention is called for, as are also a series of protective measures.
INTRODUCTION In recent years the Mediterranean has been the central topic of various consultations, symposia, meetings of experts and international conferences. In 1973 the International Conference on Marine Pollution, convened on the initiative of the Inter-Governmental Maritime Consultative Organization ( I M C O ) , d e s i g n a t e d t h e M e d i t e r r a n e a n as a s p e c i a l a r e a f o r t h e p u r p o s e s o f a p p l y i n g t h e R e g u l a t i o n s f o r t h e P r e v e n t i o n o f P o l l u t i o n b y O i l .1 T h e U n i t e d N a t i o n s E n v i r o n m e n t P r o g r a m m e , f o r its p a r t , in c o l l a b o r a tion with the competent specialized agencies of the United Nations, has drawn up a comprehensive plan of action of which the Barcelona Convention and its two Protocols .2, which concern maritime activities, are an important part. I t is n o t s u r p r i s i n g t h a t t h e f i r s t m e a s u r e s w h i c h t h e c o a s t a l S t a t e s d e c i d e d to adopt and to put into effect jointly concerned the pollution of the Medi-
• 1 International Convention for the Prevention of Pollution from Ships, 1973, Annex I, Regulation 10. • 2 A d o p t e d by the Conference of Plenipotentiaries of the Coastal States of the Mediterranean Region on the Protection of the Mediterranean Sea.
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terranean b y ships: such pollution occurs on a spectacular scale and is relatively well known; measures to c o m b a t it do not pose political, economic, industrial or social problems such as those raised by measures to c o m b a t pollution o f o t h e r kinds, particularly from land-based sources. In order to appreciate the implications and scale of the efforts that are being made, it is necessary t o identify the reasons why the sea routes crossing the Mediterranean have recently begun to cause so much pollution, to a t t e m p t to anticipate what trends will occur in the immediate future and finally to draw some conclusions.
HISTORY OF T R A D E A N D N A V I G A T I O N Even in r e m o t e antiquity -- between 4000 and 3000 B.C. -- the people of Crete had sea c o m m u n i c a t i o n s with Greece and Egypt. Later the Egyptians established maritime relations with Syria, Cyprus and Greece. In about 1300 B.C. the Egyptian fleet exercised control over the Levant and the Aegean, protecting the extensive c om m e r ce with the Phoenician and Syrian ports where Egyptian ships t o o k on cargoes of timber, gold and silver, and spices brought b y caravans f r om Arabia and the East. The Phoenicians t o o k part in this trade and in the end even supplanted the Egyptians. Th ey occupied, indeed, a privileged position at the focal poi nt of the trade routes o f their time. Their ports were the western terminals of the caravan routes f r om Armenia, Assyria, Babylon and Persia. T h e y had access by sea to Egypt, Cyprus, Crete and Greece. A flourishing trade in grain enabled t h e m to set up large warehouses on the island of Cythera. But t h e y also pushed westwards, establishing colonies at Utica, Carthage and even b e y o n d the Pillars of Hercules (Gibraltar) at Cadiz. F r o m 450 B.C. onwards t h e y faced c o m p e t i t i o n from the Greeks who began by trading with Egypt, with the ports of Phoenicia (Tyre, Sidon, Beirut) and with a n u m b e r o f colonies which t h ey set up on the coasts of Asia Minor. T h e y also established themselves in Sicily, in southern Italy (Taranto) and in th e south o f France (Marseilles). T h e y later ventured b e y o n d the Mediterranean and were pr oba bl y the first t o bring back tin from the Isles of Scilly and Cornwall. The establishment of the R o m a n Empire was t o give considerable impetus to sea-borne c o m m e r c e across the Mediterranean as the needs of the Empire were considerable and the R o m a n fleets stamped out piracy in the Mediterranean and the Black Sea. R o m e i m p o r t e d cereals from Egypt and Africa and traded with China and India through th e ports o f Syria where the caravans arrived, or along the Nile as far as Coptos, over a "land bridge" f r om Coptos to Myos Hermos on the
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R e d Sea a n d f r o m t h e r e on t o India. N a v i g a t i o n was m a d e easier b y t h e e x i s t e n c e o f " g e o g r a p h i e s " - - in particular t h a t o f S t r a b o - - a n d o f " i t i n e r a r i e s " w h i c h i n c l u d e d i n s t r u c t i o n s to n a v i g a t o r s a n d a c o m m e r c i a l g a z e t t e e r w h i c h k e p t c o p y i s t s h a r d at w o r k . L i g h t h o u s e s a n d b e a c o n s w e r e e r e c t e d , in p a r t i c u l a r at Ostia a n d A l e x a n d r i a . H a r b o u r s w e r e enlarged a n d i m p r o v e d . T h e decline a n d fall o f t h e R o m a n E m p i r e b r o u g h t a b o u t a c o n s i d e r a b l e r e d u c t i o n in s e a - b o r n e c o m m e r c e . A l t h o u g h B y z a n t i u m c o n t i n u e d to engage in t r a d e b e t w e e n E a s t a n d West, t h e p r e s e n c e of Saracen fleets in the Medit e r r a n e a n d e n i e d f r e e d o m o f m o v e m e n t t o all fleets o t h e r t h a n t h a t o f By z a n t i u m . A n u m b e r o f m a r i t i m e cities such as Venice, G e n o a , Ragusa, Marseilles and B a r c e l o n a c o n t i n u e d sea-going activities on a m o d e s t scale. In 1 0 8 1 , u n d e r t h e t e r m s o f a t r e a t y , Venice s e c u r e d a privileged s i t u a t i o n in C o n s t a n t i n o p l e in e x c h a n g e f o r assisting t h e B y z a n t i n e E m p i r e against t h e N o r m a n s w h o h a d e s t a b l i s h e d t h e m s e l v e s on Malta. It was as a result o f t h e Crusades w h i c h r e c a p t u r e d t h e Syrian p o r t s f r o m t h e Saracens and, in t h e 1 3 t h c e n t u r y , C o n s t a n t i n o p l e , t h a t t h e r e p u b l i c s o f V e n i c e a n d G e n o a o n c e m o r e r e s u m e d m a r i t i m e traffic b e t w e e n the p o r t s o f t h e Black Sea, Syria, E g y p t , Spain, t h e s o u t h o f F r a n c e a n d N o r t h Africa. T h e G e n o e s e a n d V e n e t i a n fleets carried silk and spices f r o m t h e Orient, as well as wine, oil a n d d y e s t u f f s p r o d u c e d by t h e M e d i t e r r a n e a n c o u n t r i e s , to E n g l a n d , F l a n d e r s a n d n o r t h e r n E u r o p e . At t h e e n d o f t h e 1 5 t h a n d t h e b e g i n n i n g of t h e 1 6 t h c e n t u r y , t h e fall o f C o n s t a n t i n o p l e , t h e d i s c o v e r y o f sea r o u t e s to I n d i a a n d t h e East a n d t h e d i s c o v e r y o f t h e West Indies a n d A m e r i c a s h i f t e d m a r i t i m e activities f r o m t h e M e d i t e r r a n e a n to t h e oceans.
TABLE I Suez Canal traffic * Year
1927 1933 1938 1946 1955 1966
Dry cargo Oil (1,000 tonnes) (1,000 tonnes) southbound northbound
total
26,018 21,355 23,276 13,482 38,710 66,222
3,505 5,560 5,303 8,444 68,798 175,671
347 627 283 73 1,095 8,953
3,158 4,933 5,220 8,371 66,893 166,718
Grand total (1,000 tonnes)
Oil (%)
29,523 26,915 28,779 21,926 107,508 241,893
11.87 20.65 19.12 38.51 64.00 72.62
Figures taken from the Year Book of the Chamber of Shipping of the United Kingdom.
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THE SUEZ C A N AL The opening of the Suez Canal in 1869 made the Mediterranean a through ro u t e for international trade between West and East. It considerably shortened the sea passage for such trade which had previously been obliged to go r o u n d the southern tip of Africa. It also f urt hered relations between the countries on the Black Sea and those in the East. Traffic through the Suez Canal was to provide a very good indicator of the volume of sea-borne trade passing t hr ough the Mediterranean. Although Ferdinand de Lesseps had originally anticipated an annual movem e n t of ships with a total net tonnage of six million tons, in 1910 a total of 4,533 ships with a net tonnage of 16.5 million tons passed through the Canal. Table I gives an idea of the increase in traffic passing through the Canal and, thus through the Mediterranean between 1927 and 1966. The figures in this table highlight the obvious strategic and logistic importance of the Mediterranean and the Canal during the two world wars. After the end of the second World War the traffic increased rapidly and, in 1948, reached the figure of 8,686 ships with a net tonnage of 55 million tons. Since that time, Canal traffic, although maintaining its rate of growth, u n d er wen t a change. Passenger ships which had been of major importance on the shipping routes from Europe to the Far East were due to disappear, being driven o u t of business by the overwhelming com pet i t i on from aircraft. On the o th er hand, the t r a ns por t of oil from the Middle East t o western E u ro p e and even to the American cont i nent was to increase considerably and in 1966 -- the last normal year before the Canal was closed in June 1967 following the Israeli-Arab War -- a m o u n t e d to over 72% of the total traffic. In 1967, 544,000 tonnes of petrol a day transited the Canal -- before it was closed -- and the Mediterranean. North Africa, on the ot her hand, during the same year, delivered 435,000 tonnes a day before the closure of the Canal and 462,000 tonnes a day after its closure *' The nature of oil cargoes under w ent a change with the gradual replacem e n t of refined products by crude oil as refineries were set up in the consumer countries. For reasons which will be explained below, this resulted in a considerable increase in pollution of the sea by oil. The shipment o f miscellaneous cargoes in the Mediterranean, as reflected in traffic transiting the Suez Canal, mainly concerned fertilizers and fin-
*1 Figures taken from Le Transport Maritime, a journal published annually by the Comit6 central des armateurs de France.
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ished metal commodities in the north--south direction and ores, metals and other goods such as tea in the south--north direction. During the period when the Suez Canal was closed (June 1967--June 1975), the shipment of miscellaneous goods between the countries of Asia and the Far East and the countries bordering on the Mediterranean or the Black Sea went via the Cape of Good Hope and Gibraltar. The same applied to large quantities of oil carried in increasingly large oil tankers. Nevertheless, the countries of the Mediterranean and of northwestern Europe were also supplied with oil from the loading ports along the east coast of the eastern Mediterranean basin which were fed by pipeline: Banias and Tartous in Syria, Tripoli and Saida in Lebanon and, until 1973, Ashkelon in Israel. Thus a considerable tanker traffic became established, crossing the Mediterranean fully laden from east to west and returning in ballast from west to east. Table II shows the quantities of crude oil loaded in the first four of the abovementioned ports between 1968 and 1976. The table also shows tanker traffic from the ports of Libya and Algeria bound for ports in southern or western Europe. In addition to such traffic, the shipment of liquefied natural gas from Libya and Algeria to Italy, France, Spain, Great Britain and now the United States of America should also be taken into account. Lastly, it should be noted that, although no very precise data are available, the bulk shipment of noxious or dangerous cargoes has also been taking place in the Mediterranean. T A B L E II Q u a n t i t i e s o f c r u d e oil (in million o f t o n n e s ) l o a d e d at t e r m i n a l s in the eastern Mediterr a n e a n , and in N o r t h Africa Year
Oil f r o m t h e Middle East l o a d e d at t e r m i n a l s in t h e eastern Mediterranean *
Oil loaded at N o r t h African t e r m i n a l s by t h e e x p o r t i n g c o u n t r i e s o f the region and b o u n d for Western E u r o p e **
1968 1969 1970 1971 1972 1973 1974 1975
81.2 145 61.8 47.5 61 77.3 49.4 47.7
159.75 185 220 158 129 120 91 75
* Figures calculated by t h e a u t h o r o n t h e basis o f statistics e x p r e s s e d in barrels p e r day kindly m a d e available to h i m by Shell I n t e r n a t i o n a l . ** Figures t a k e n f r o m " L e T r a n s p o r t M a r i t i m e " .
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The re-opening of the Suez Canal brought about certain changes in the sea routes taken by ships transporting dry and miscellaneous cargoes. This applies, for example, to cargoes from Asia and the Far East b o u n d for countries bordering the Mediterranean and the Black Sea and vice versa. It also gave an impetus to roll-on/roll-off freight traffic which had begun between Genoa, Sardinia and Sicily in 1967--1969. It was in North Africa and, above all, in the near East that the greatest expansion in r.o./r.o, traffic t o o k place. As a result of the considerable econom i c potential of the oilproducing countries, on the one hand, and of the swift and inevitable congestion in the Near East ports, on the other, the roll-on/roll-off ship was clearly the most satisfactory t ype of ship from the technical point of view. The Venetians, th r o u g h their c o m p a n y "Adriatica", have once again displayed the vitality o f their ancestors b'y providing a sea link between nort hern Europe, the south of the Mediterranean and the Near East. Very recently, however, a still more spectacular innovation has made its appearance in the shape of e n o r m o u s triple-decker pushed barges operating a regular service between Marseilles and Saudi Arabia. On the o th er hand, the re-opening of the Suez Canal did not give rise to any drastic change in the Mediterranean tanker traffic because its cross-section was still limited. Nevertheless, it should be not ed that large tankers in excess o f 200,000 tons dead-weight increasingly transit the Canal in the n o r t h - - s o u t h direction in ballast on their way to load oil in the Gulf. In O c t o b e r 1976, for example, the tanker "Esso Skandia" of 254,011 tons deadweight was able to transit the Canal in the light condition.
M E D I T E R R A N E A N SEA POLLUTION This new traffic will inevitably exacerbate the seriousness of oil pollution in the Mediterranean for reasons which will be explained below. The pollution of the sea by oil (in the main crude oil) transported by ships has two main causes: (1) intentional and habitual discharge; (2) accidents involving tankers.
Intentional and habitual discharge of oil This source o f pollution is directly related to the operation of tankers. Indeed, a p p r o x i m a t e l y 1% of the crude oil cargo is lost in the course of each voyage either by evaporation of the more volatile elements or, above all, as a result o f the f o r m a t i o n o f layers which adhere to the b o t t o m and sides of cargo tanks.
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When a t a n k e r leaves an oil discharge p o r t , unless it is e q u i p p e d with segregated ballast tanks, it must fill a certain n u m b e r o f tanks t h a t are poll u t e d by oil residues with water. This w a t e r is essential as ballast to ensure the m a n o e u v r a b i l i t y and s a f e t y of the ship. T h e v o l u m e o f ballast t r a n s p o r t e d in this way generally varies b e t w e e n 30% in g o o d w e a t h e r c o n d i t i o n s and 50% in bad weather. During t h e r e t u r n voyage t o the loading port, t h e tanks are cleaned and the t a n k washings, a m i x t u r e of w a t e r and c r u d e oil, are discharged into the sea. Thus the deliberate discharge o f t a n k washing water is o n e o f the causes o f the p o l l u t i o n o f the sea by oil. In o r d e r t o mitigate the p o l l u t a n t effects o f such discharges, the oil industry d e v e l o p e d a t e c h n i q u e early in the 1 9 6 0 ' s k n o w n as the " l o a d - o n - t o p syst e m " which entails keeping t h e m i x t u r e o f water and crude oil on board, separating the w a t e r f r o m the crude oil and t h e n discharging the w a t e r while retaining the c r u d e oil residues which are thus included as part o f the ship's n e x t cargo. It is e s t i m a t e d t h a t some 80% of tankers use this s y s t e m which considerably reduces p o l l u t i o n b u t does n o t p r e v e n t it entirely because the w a t e r discharged nevertheless contains a certain a m o u n t o f oil. It should also be n o t e d t h a t t h e results are less satisfactory in the case o f short voyages, for e x a m p l e i n t r a - M e d i t e r r a n e a n voyages. F u r t h e r m o r e , tankers c o m i n g f r o m o t h e r regions o f the world and transiting the M e d i t e r r a n e a n in ballast generally t a k e advantage o f the m o r e f a v o u r a b l e w e a t h e r c o n d i t i o n s obtaining in the M e d i t e r r a n e a n to clean t h e i r tanks and their ballast. It is t h e r e f o r e likely t h a t the passage t h r o u g h the M e d i t e r r a n e a n o f v e r y large tankers transiting the Suez Canal in balast might m e a n an increase in p o l l u t i o n . One idea which n a t u r a l l y c o m e s t o m i n d as a means o f r e m e d y i n g this state o f affairs is p u r e l y and simply to p r o h i b i t such deliberate and habitual discharges. T h a t is the t r e n d o f i n t e r n a t i o n a l regulations drawn up r e c e n t l y u n d e r the auspices o f IMCO in o r d e r to p r o t e c t semi-enclosed seas such as the Mediterranean, the Black Sea, the R e d Sea and the Gulf Area. H o w e v e r , for a n u m b e r o f years t o c o m e a s o m e w h a t d i f f e r e n t s i t u a t i o n will prevail. T h e i n t e r n a t i o n a l regulations c u r r e n t l y in f o r c e up to J a n u a r y 1972, n a m e l y the I n t e r n a t i o n a l C o n v e n t i o n for the P r e v e n t i o n o f P o l l u t i o n o f t h e Sea o f Oil, 1 9 5 4 , as a m e n d e d in 1 9 6 2 , p e r m i t t e d the discharge into the Medi t e r r a n e a n within 100 miles f r o m coasts o f m i x t u r e s with an oil c o n t e n t equal to n o t m o r e t h a n 100 parts to 1 , 0 0 0 , 0 0 0 parts of the m i x t u r e . B e y o n d 100 miles f r o m coasts t h e r e was no restriction on discharges. Thus tankers c o u l d freely discharge their slops into the M e d i t e r r a n e a n in t w o areas one o f which is situated b e t w e e n Sicily, s o u t h e r n G r e e c e and the coast o f L i b y a and the o t h e r b e t w e e n Crete, C y p r u s and the coast of E g y p t . T h e approxi-
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mate coordinates o f these two areas were, respectively: 3 7°3 0 N 180°30E; 34°00N 15°10E; 32°35N 18°05E, 34°45N 20°45E; and 34°35N 30°20E; 33°15N 26°25E; 33°15N 30°45E. F o r t u n a t e l y , this situation came to an end on 20 January 1978 when the 1969 a m e n d m e n t , prepared and a d o p t e d by IMCO, to the above-mentioned 1954 Convention, as amended in 1962, came into force. Under the terms of the new a m e n d m e n t all discharges whatever their oil c o n t e n t are now prohibited within 50 miles of coasts, and b e y o n d 50 miles from coasts the rate of discharge must n o t exceed 60 1 per mile travelled in the case of ballast water or contain mo r e than 100 parts per million in the case of effluent mixed with oil cargo residues. Lastly, after the International Convention for the Prevention of Pollution f r o m Ships, 1973, also prepared under the auspices of IMCO, comes into force, all discharges of whatever kind will be prohibited in the Mediterranean which for this purpose is designated by the Convention as a "special area".
Accidental pollution on a massive scale
Pollution o f this kind is generally the result of accidents -- groundings or collisions -- involving tankers. The best known example is that of the "Torrey C a n y o n " in March 1967. Such pollution causes serious damage to local marine life and to coastal countries and is a m a t t e r of concern for public opinion. Most accidents are caused by human error. Thus a great deal is now being done in an ef f o r t to improve navigational conditions, in particular by introducing traffic separation schemes in areas of convergence or high traffic density, and to raise the standards of training of sea-going personnel. Although the meteorological conditions are more favourable than in ot her seas -- in spite of f r equent and violent storms in winter -- there is still a risk o f such accidents occurring in the Mediterranean. In order to appreciate the risk t o be faced by coastal countries as a result o f deliberate or accidental pollution, one must bear in mind the influence of winds and currents in the Mediterranean and certain hydrological factors. Away from the coasts, the general wind patterns over the Mediterranean as a whole, d o m i n a t e d by the three "lungs" of the Mediterranean -- the Gulf of Lions, the upper Adriatic and the Aegean -- is characterized by: (1) a prep o n d e r a n c e o f n o r t hw e s t er l y winds between April and September, generally light to moderate; (2) winds blowing both from the nort h and from the n o r t h wes t in October; (3) the lack of any p r e p o n d e r a n t wind from November to January, although winds f r om southwest to northeast, including northwesterlies are more frequent than winds blowing from the opposite semicircle; and (4) fairly f r e que nt gales from January to April.
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METEOROLOGICAL AND OCEANOGRAPHICAL DATA O n l y a t h i r d o f the w a t e r loss in the M e d i t e r r a n e a n as a result o f evaporat i o n is o f f s e t b y t h e i n f l o w o f fresh w a t e r f r o m coastal rivers. The r e m a i n i n g t w o - t h i r d s are m a d e up by the i n f l o w o f water f r o m the Atlantic t h r o u g h the Straits o f Gibraltar. This explains the e x i s t e n c e of an east-going surface c u r r e n t along t h e n o r t h coast of Africa. Part o f t h e c u r r e n t is d e f l e c t e d by Sicily and the s o u t h e r n part o f Italy and flows along the west coast o f Italy and t h e n turns w e s t w a r d along the F r e n c h coast and t h e n s o u t h w a r d o f f the Spanish coast. T h e o t h e r part o f t h e c u r r e n t c o n t i n u e s t h r o u g h the Malta Channel in an easterly d i r e c t i o n along the coasts o f C y r e n a i c a and E g y p t , turns n o r t h w a r d along the coast o f Israel and Syria and t h e n returns westward along the coast o f T u r k e y and n o r t h e r n Crete. T h e c u r r e n t is t h e n j o i n e d b y the surface w a t e r flowing f r o m the Black Sea t h r o u g h the Bosporus, the Sea o f Marmara and the Dardanelles. One b r a n c h o f the c u r r e n t follows the western coast o f G r e e c e and e n t e r s the Adriatic where it flows along the coasts o f Albania and Yugoslavia r e t u r n i n g in the o p p o s i t e d i r e c t i o n along the coast o f Italy. It can t h u s be seen t h a t the general d i r e c t i o n o f the surface circulation in the western basin, as well as in the eastern basin o f the M e d i t e r r a n e a n and in the Adriatic, is c o u n t e r - c l o c k w i s e . Observations m a d e on shipping r o u t e s indicate t h a t the speed o f the curr e n t rarely exceeds a rate o f 1 k n o t and, c o n s e q u e n t l y , its d i r e c t i o n , in the case o f t h e c u r r e n t r e t u r n i n g westward, is subject t o wide local variations as a result o f high winds. T h e m i n i m u m d e e p - w a t e r t e m p e r a t u r e is b r o a d l y similar to the average surface t e m p e r a t u r e in winter. Thus, t h e r e are no vertical c u r r e n t s in t h e M e d i t e r r a n e a n such as w o u l d be caused b y wide differences b e t w e e n the bott o m and surface t e m p e r a t u r e s . T h e masses o f water in c o n t a c t with the a t m o s p h e r e d o n o t circulate rapidly enough t o cause a d e q u a t e o x y g e n a t i o n . It has been e s t i m a t e d t h a t it takes a b o u t 80 years for the mass o f w a t e r b e t w e e n the surface and a d e p t h o f 150 m t o b e c o m e m i x e d and r e - o x y g e n ated. C o n s e q u e n t l y a n y substance t h a t does n o t sink or disintegrate rapidly m a y r e m a i n for a very long t i m e in suspension near the surface or within this layer o f water. This is a very serious m a t t e r in the case o f p o l l u t a n t or n o x i o u s substances. T h e above d a t a m a k e it clear t h a t p o l l u t i o n , f r o m w h a t e v e r source, will n o t be s u b j e c t e d t o such extensive or rapid biological d e g r a d a t i o n as in t h e o p e n seas. Moreover, t h e set o f the prevailing winds and the d i r e c t i o n o f the currents a c c o u n t for t h e serious p o l l u t i o n t h a t occurs in the t w o basins o f the M e d i t e r r a n e a n : (a) on the s o u t h e r n and eastern coasts o f t h e eastern M e d i t e r r a n e a n basin, t o say n o t h i n g o f the large-scale p o l l u t i o n t h a t occurs
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elsewhere, in particular in the Dardanelles, the Aegean and the Adriatic; (b) in the western basin on the coasts of North Africa, Italy, France and Spain. It must be acknowledged, however, that pollution on the coasts of the three last named countries is mainly caused by oil from industrial sources and not from ships.
FUTURE PROSPECTS Assuming that peace prevails in the region, it is reasonable to expect a continuous expansion of maritime traffic in the Mediterranean both for miscellaneous cargoes and for bulk cargoes of dangerous or noxious substances and for oil products. It is likely, therefore, that there will be an increase in the density of commercial shipping and also in certain pollution hazards. Ships will ply the Mediterranean in ever greater numbers between east and west and between north and south in order to satisfy the growing needs of expanding maritime trade particularly with the countries of the Middle East whose economic potential is growing rapidly. The currently planned widening and deepening of the Suez Canal and the putting into service of an oil pipeline from Suez to the Mediterranean (SuMed) in parallel to the Suez Canal are likely to attract through the Mediterranean a substantial proportion of the shipments of oil which at present take the route round Africa. The intersection of increasingly busy shipping routes and the convergence of many such routes in certain areas causing an appreciable rise in traffic density will increase the risks of accidents and collisions in spite of the good visibility which generally prevails in the Mediterranean. The risk of massive and accidental pollution will thus inevitably increase. Admittedly, if present plans to expand the capacity of oil-refining facilities at the place of production are carried out, the transport of such products will present less threat to the marine environment. On the other hand, the increasingly large quantities of dangerous and noxious bulk chemicals will be a more serious environmental hazard. With regard to deliberate and habitual pollution by oil from ships, it is to be hoped that the entry into force of the 1969 amendments to the International Convention of 1954/1962, on the one hand, and of the International Convention of 1973, on the other, will provide a means of eliminating it completely.
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CONCLUSIONS Although n o t as dramatic or even as extensive and serious as pollution from land-based sources, the pollution of the Mediterranean by ships is a m a t t e r on which a t t e n t i o n should be focused and which calls for co-ordinated and co-operative efforts on the part o f the coastal countries and of other countries outside the region whose ships use the Mediterranean either for trade with Mediterranean countries or as a through-route to or from o t h e r regions o f the world. In particular, the countries concerned ought: (a) to make every ef f or t to expedite the entry into force of the International Convention o f 1973, and the Mediterranean countries should, in addition, address themselves to the task, wherever there seems t o be a need, o f establishing the reception facilities for oily wastes specified by the Convention; (b) to co-operate very closely with the Regional Oil-Combating Centre, set up in Malta b y the United Nations E n v i r o n m e n t Programme thanks to the generous hospitality of the G o v e r n m e n t of the Republic of Malta, the operation of which has been entrusted to IMCO; (c) to prepare and adopt, as required, within the fram ew ork of IMCO, schemes f o r the separation of traffic at the points of intersection of transMediterranean routes or in areas with a high traffic density; (d) to compile statistical data on quantities and destinations, and scientific data ,1 on the hazards to the marine envi r o nm ent of cargoes of dangerous and noxious substances transported in bulk; (e) subsequently, insofar as the data thus gathered indicate a need, to ensure, by means of an a m e n d m e n t to the International Convention of 1973, that the Mediterranean is regarded as a "special area" in which any discharge of such substances would be prohibited. Such an a m e n d m e n t would, moreover, make it obligatory for countries bordering the Mediterranean to establish reception stations for wastes and residues o f such substances.
• 1 The Group of Experts on the Scientific Aspects of Marine Pollution (GESAMP) has already begun to work on this task.
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T h e M e d i t e r r a n e a n as a M a r i t i m e T r a d e R o u t e J. Qu~guiner Administrateur O~n~ral des Affaires Maritimes, Paris (France)
ABSTRACT Ever since earliest antiquity, the Mediterranean has served as a channel for trade both between the countries bordering upon it and later, with the refinement of navigation techniques, with the other regions of the world. With the opening of the Suez Canal, it became a crossroad for shipping trade between North and South and between East and West. Especially vulnerable because it is semi-enclosed, the Mediterranean is threatened both by the nature of the cargoes being transported and by the density of maritime traffic. In order to safeguard the Mediterranean, special attention is called for, as are also a series of protective measures.
INTRODUCTION In recent years the Mediterranean has been the central topic of various consultations, symposia, meetings of experts and international conferences. In 1973 the International Conference on Marine Pollution, convened on the initiative of the Inter-Governmental Maritime Consultative Organization ( I M C O ) , d e s i g n a t e d t h e M e d i t e r r a n e a n as a s p e c i a l a r e a f o r t h e p u r p o s e s o f a p p l y i n g t h e R e g u l a t i o n s f o r t h e P r e v e n t i o n o f P o l l u t i o n b y O i l .1 T h e U n i t e d N a t i o n s E n v i r o n m e n t P r o g r a m m e , f o r its p a r t , in c o l l a b o r a tion with the competent specialized agencies of the United Nations, has drawn up a comprehensive plan of action of which the Barcelona Convention and its two Protocols .2, which concern maritime activities, are an important part. I t is n o t s u r p r i s i n g t h a t t h e f i r s t m e a s u r e s w h i c h t h e c o a s t a l S t a t e s d e c i d e d to adopt and to put into effect jointly concerned the pollution of the Medi-
• 1 International Convention for the Prevention of Pollution from Ships, 1973, Annex I, Regulation 10. • 2 A d o p t e d by the Conference of Plenipotentiaries of the Coastal States of the Mediterranean Region on the Protection of the Mediterranean Sea.
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terranean b y ships: such pollution occurs on a spectacular scale and is relatively well known; measures to c o m b a t it do not pose political, economic, industrial or social problems such as those raised by measures to c o m b a t pollution o f o t h e r kinds, particularly from land-based sources. In order to appreciate the implications and scale of the efforts that are being made, it is necessary t o identify the reasons why the sea routes crossing the Mediterranean have recently begun to cause so much pollution, to a t t e m p t to anticipate what trends will occur in the immediate future and finally to draw some conclusions.
HISTORY OF T R A D E A N D N A V I G A T I O N Even in r e m o t e antiquity -- between 4000 and 3000 B.C. -- the people of Crete had sea c o m m u n i c a t i o n s with Greece and Egypt. Later the Egyptians established maritime relations with Syria, Cyprus and Greece. In about 1300 B.C. the Egyptian fleet exercised control over the Levant and the Aegean, protecting the extensive c om m e r ce with the Phoenician and Syrian ports where Egyptian ships t o o k on cargoes of timber, gold and silver, and spices brought b y caravans f r om Arabia and the East. The Phoenicians t o o k part in this trade and in the end even supplanted the Egyptians. Th ey occupied, indeed, a privileged position at the focal poi nt of the trade routes o f their time. Their ports were the western terminals of the caravan routes f r om Armenia, Assyria, Babylon and Persia. T h e y had access by sea to Egypt, Cyprus, Crete and Greece. A flourishing trade in grain enabled t h e m to set up large warehouses on the island of Cythera. But t h e y also pushed westwards, establishing colonies at Utica, Carthage and even b e y o n d the Pillars of Hercules (Gibraltar) at Cadiz. F r o m 450 B.C. onwards t h e y faced c o m p e t i t i o n from the Greeks who began by trading with Egypt, with the ports of Phoenicia (Tyre, Sidon, Beirut) and with a n u m b e r o f colonies which t h ey set up on the coasts of Asia Minor. T h e y also established themselves in Sicily, in southern Italy (Taranto) and in th e south o f France (Marseilles). T h e y later ventured b e y o n d the Mediterranean and were pr oba bl y the first t o bring back tin from the Isles of Scilly and Cornwall. The establishment of the R o m a n Empire was t o give considerable impetus to sea-borne c o m m e r c e across the Mediterranean as the needs of the Empire were considerable and the R o m a n fleets stamped out piracy in the Mediterranean and the Black Sea. R o m e i m p o r t e d cereals from Egypt and Africa and traded with China and India through th e ports o f Syria where the caravans arrived, or along the Nile as far as Coptos, over a "land bridge" f r om Coptos to Myos Hermos on the
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R e d Sea a n d f r o m t h e r e on t o India. N a v i g a t i o n was m a d e easier b y t h e e x i s t e n c e o f " g e o g r a p h i e s " - - in particular t h a t o f S t r a b o - - a n d o f " i t i n e r a r i e s " w h i c h i n c l u d e d i n s t r u c t i o n s to n a v i g a t o r s a n d a c o m m e r c i a l g a z e t t e e r w h i c h k e p t c o p y i s t s h a r d at w o r k . L i g h t h o u s e s a n d b e a c o n s w e r e e r e c t e d , in p a r t i c u l a r at Ostia a n d A l e x a n d r i a . H a r b o u r s w e r e enlarged a n d i m p r o v e d . T h e decline a n d fall o f t h e R o m a n E m p i r e b r o u g h t a b o u t a c o n s i d e r a b l e r e d u c t i o n in s e a - b o r n e c o m m e r c e . A l t h o u g h B y z a n t i u m c o n t i n u e d to engage in t r a d e b e t w e e n E a s t a n d West, t h e p r e s e n c e of Saracen fleets in the Medit e r r a n e a n d e n i e d f r e e d o m o f m o v e m e n t t o all fleets o t h e r t h a n t h a t o f By z a n t i u m . A n u m b e r o f m a r i t i m e cities such as Venice, G e n o a , Ragusa, Marseilles and B a r c e l o n a c o n t i n u e d sea-going activities on a m o d e s t scale. In 1 0 8 1 , u n d e r t h e t e r m s o f a t r e a t y , Venice s e c u r e d a privileged s i t u a t i o n in C o n s t a n t i n o p l e in e x c h a n g e f o r assisting t h e B y z a n t i n e E m p i r e against t h e N o r m a n s w h o h a d e s t a b l i s h e d t h e m s e l v e s on Malta. It was as a result o f t h e Crusades w h i c h r e c a p t u r e d t h e Syrian p o r t s f r o m t h e Saracens and, in t h e 1 3 t h c e n t u r y , C o n s t a n t i n o p l e , t h a t t h e r e p u b l i c s o f V e n i c e a n d G e n o a o n c e m o r e r e s u m e d m a r i t i m e traffic b e t w e e n the p o r t s o f t h e Black Sea, Syria, E g y p t , Spain, t h e s o u t h o f F r a n c e a n d N o r t h Africa. T h e G e n o e s e a n d V e n e t i a n fleets carried silk and spices f r o m t h e Orient, as well as wine, oil a n d d y e s t u f f s p r o d u c e d by t h e M e d i t e r r a n e a n c o u n t r i e s , to E n g l a n d , F l a n d e r s a n d n o r t h e r n E u r o p e . At t h e e n d o f t h e 1 5 t h a n d t h e b e g i n n i n g of t h e 1 6 t h c e n t u r y , t h e fall o f C o n s t a n t i n o p l e , t h e d i s c o v e r y o f sea r o u t e s to I n d i a a n d t h e East a n d t h e d i s c o v e r y o f t h e West Indies a n d A m e r i c a s h i f t e d m a r i t i m e activities f r o m t h e M e d i t e r r a n e a n to t h e oceans.
TABLE I Suez Canal traffic * Year
1927 1933 1938 1946 1955 1966
Dry cargo Oil (1,000 tonnes) (1,000 tonnes) southbound northbound
total
26,018 21,355 23,276 13,482 38,710 66,222
3,505 5,560 5,303 8,444 68,798 175,671
347 627 283 73 1,095 8,953
3,158 4,933 5,220 8,371 66,893 166,718
Grand total (1,000 tonnes)
Oil (%)
29,523 26,915 28,779 21,926 107,508 241,893
11.87 20.65 19.12 38.51 64.00 72.62
Figures taken from the Year Book of the Chamber of Shipping of the United Kingdom.
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THE SUEZ C A N AL The opening of the Suez Canal in 1869 made the Mediterranean a through ro u t e for international trade between West and East. It considerably shortened the sea passage for such trade which had previously been obliged to go r o u n d the southern tip of Africa. It also f urt hered relations between the countries on the Black Sea and those in the East. Traffic through the Suez Canal was to provide a very good indicator of the volume of sea-borne trade passing t hr ough the Mediterranean. Although Ferdinand de Lesseps had originally anticipated an annual movem e n t of ships with a total net tonnage of six million tons, in 1910 a total of 4,533 ships with a net tonnage of 16.5 million tons passed through the Canal. Table I gives an idea of the increase in traffic passing through the Canal and, thus through the Mediterranean between 1927 and 1966. The figures in this table highlight the obvious strategic and logistic importance of the Mediterranean and the Canal during the two world wars. After the end of the second World War the traffic increased rapidly and, in 1948, reached the figure of 8,686 ships with a net tonnage of 55 million tons. Since that time, Canal traffic, although maintaining its rate of growth, u n d er wen t a change. Passenger ships which had been of major importance on the shipping routes from Europe to the Far East were due to disappear, being driven o u t of business by the overwhelming com pet i t i on from aircraft. On the o th er hand, the t r a ns por t of oil from the Middle East t o western E u ro p e and even to the American cont i nent was to increase considerably and in 1966 -- the last normal year before the Canal was closed in June 1967 following the Israeli-Arab War -- a m o u n t e d to over 72% of the total traffic. In 1967, 544,000 tonnes of petrol a day transited the Canal -- before it was closed -- and the Mediterranean. North Africa, on the ot her hand, during the same year, delivered 435,000 tonnes a day before the closure of the Canal and 462,000 tonnes a day after its closure *' The nature of oil cargoes under w ent a change with the gradual replacem e n t of refined products by crude oil as refineries were set up in the consumer countries. For reasons which will be explained below, this resulted in a considerable increase in pollution of the sea by oil. The shipment o f miscellaneous cargoes in the Mediterranean, as reflected in traffic transiting the Suez Canal, mainly concerned fertilizers and fin-
*1 Figures taken from Le Transport Maritime, a journal published annually by the Comit6 central des armateurs de France.
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ished metal commodities in the north--south direction and ores, metals and other goods such as tea in the south--north direction. During the period when the Suez Canal was closed (June 1967--June 1975), the shipment of miscellaneous goods between the countries of Asia and the Far East and the countries bordering on the Mediterranean or the Black Sea went via the Cape of Good Hope and Gibraltar. The same applied to large quantities of oil carried in increasingly large oil tankers. Nevertheless, the countries of the Mediterranean and of northwestern Europe were also supplied with oil from the loading ports along the east coast of the eastern Mediterranean basin which were fed by pipeline: Banias and Tartous in Syria, Tripoli and Saida in Lebanon and, until 1973, Ashkelon in Israel. Thus a considerable tanker traffic became established, crossing the Mediterranean fully laden from east to west and returning in ballast from west to east. Table II shows the quantities of crude oil loaded in the first four of the abovementioned ports between 1968 and 1976. The table also shows tanker traffic from the ports of Libya and Algeria bound for ports in southern or western Europe. In addition to such traffic, the shipment of liquefied natural gas from Libya and Algeria to Italy, France, Spain, Great Britain and now the United States of America should also be taken into account. Lastly, it should be noted that, although no very precise data are available, the bulk shipment of noxious or dangerous cargoes has also been taking place in the Mediterranean. T A B L E II Q u a n t i t i e s o f c r u d e oil (in million o f t o n n e s ) l o a d e d at t e r m i n a l s in the eastern Mediterr a n e a n , and in N o r t h Africa Year
Oil f r o m t h e Middle East l o a d e d at t e r m i n a l s in t h e eastern Mediterranean *
Oil loaded at N o r t h African t e r m i n a l s by t h e e x p o r t i n g c o u n t r i e s o f the region and b o u n d for Western E u r o p e **
1968 1969 1970 1971 1972 1973 1974 1975
81.2 145 61.8 47.5 61 77.3 49.4 47.7
159.75 185 220 158 129 120 91 75
* Figures calculated by t h e a u t h o r o n t h e basis o f statistics e x p r e s s e d in barrels p e r day kindly m a d e available to h i m by Shell I n t e r n a t i o n a l . ** Figures t a k e n f r o m " L e T r a n s p o r t M a r i t i m e " .
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The re-opening of the Suez Canal brought about certain changes in the sea routes taken by ships transporting dry and miscellaneous cargoes. This applies, for example, to cargoes from Asia and the Far East b o u n d for countries bordering the Mediterranean and the Black Sea and vice versa. It also gave an impetus to roll-on/roll-off freight traffic which had begun between Genoa, Sardinia and Sicily in 1967--1969. It was in North Africa and, above all, in the near East that the greatest expansion in r.o./r.o, traffic t o o k place. As a result of the considerable econom i c potential of the oilproducing countries, on the one hand, and of the swift and inevitable congestion in the Near East ports, on the other, the roll-on/roll-off ship was clearly the most satisfactory t ype of ship from the technical point of view. The Venetians, th r o u g h their c o m p a n y "Adriatica", have once again displayed the vitality o f their ancestors b'y providing a sea link between nort hern Europe, the south of the Mediterranean and the Near East. Very recently, however, a still more spectacular innovation has made its appearance in the shape of e n o r m o u s triple-decker pushed barges operating a regular service between Marseilles and Saudi Arabia. On the o th er hand, the re-opening of the Suez Canal did not give rise to any drastic change in the Mediterranean tanker traffic because its cross-section was still limited. Nevertheless, it should be not ed that large tankers in excess o f 200,000 tons dead-weight increasingly transit the Canal in the n o r t h - - s o u t h direction in ballast on their way to load oil in the Gulf. In O c t o b e r 1976, for example, the tanker "Esso Skandia" of 254,011 tons deadweight was able to transit the Canal in the light condition.
M E D I T E R R A N E A N SEA POLLUTION This new traffic will inevitably exacerbate the seriousness of oil pollution in the Mediterranean for reasons which will be explained below. The pollution of the sea by oil (in the main crude oil) transported by ships has two main causes: (1) intentional and habitual discharge; (2) accidents involving tankers.
Intentional and habitual discharge of oil This source o f pollution is directly related to the operation of tankers. Indeed, a p p r o x i m a t e l y 1% of the crude oil cargo is lost in the course of each voyage either by evaporation of the more volatile elements or, above all, as a result o f the f o r m a t i o n o f layers which adhere to the b o t t o m and sides of cargo tanks.
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When a t a n k e r leaves an oil discharge p o r t , unless it is e q u i p p e d with segregated ballast tanks, it must fill a certain n u m b e r o f tanks t h a t are poll u t e d by oil residues with water. This w a t e r is essential as ballast to ensure the m a n o e u v r a b i l i t y and s a f e t y of the ship. T h e v o l u m e o f ballast t r a n s p o r t e d in this way generally varies b e t w e e n 30% in g o o d w e a t h e r c o n d i t i o n s and 50% in bad weather. During t h e r e t u r n voyage t o the loading port, t h e tanks are cleaned and the t a n k washings, a m i x t u r e of w a t e r and c r u d e oil, are discharged into the sea. Thus the deliberate discharge o f t a n k washing water is o n e o f the causes o f the p o l l u t i o n o f the sea by oil. In o r d e r t o mitigate the p o l l u t a n t effects o f such discharges, the oil industry d e v e l o p e d a t e c h n i q u e early in the 1 9 6 0 ' s k n o w n as the " l o a d - o n - t o p syst e m " which entails keeping t h e m i x t u r e o f water and crude oil on board, separating the w a t e r f r o m the crude oil and t h e n discharging the w a t e r while retaining the c r u d e oil residues which are thus included as part o f the ship's n e x t cargo. It is e s t i m a t e d t h a t some 80% of tankers use this s y s t e m which considerably reduces p o l l u t i o n b u t does n o t p r e v e n t it entirely because the w a t e r discharged nevertheless contains a certain a m o u n t o f oil. It should also be n o t e d t h a t t h e results are less satisfactory in the case o f short voyages, for e x a m p l e i n t r a - M e d i t e r r a n e a n voyages. F u r t h e r m o r e , tankers c o m i n g f r o m o t h e r regions o f the world and transiting the M e d i t e r r a n e a n in ballast generally t a k e advantage o f the m o r e f a v o u r a b l e w e a t h e r c o n d i t i o n s obtaining in the M e d i t e r r a n e a n to clean t h e i r tanks and their ballast. It is t h e r e f o r e likely t h a t the passage t h r o u g h the M e d i t e r r a n e a n o f v e r y large tankers transiting the Suez Canal in balast might m e a n an increase in p o l l u t i o n . One idea which n a t u r a l l y c o m e s t o m i n d as a means o f r e m e d y i n g this state o f affairs is p u r e l y and simply to p r o h i b i t such deliberate and habitual discharges. T h a t is the t r e n d o f i n t e r n a t i o n a l regulations drawn up r e c e n t l y u n d e r the auspices o f IMCO in o r d e r to p r o t e c t semi-enclosed seas such as the Mediterranean, the Black Sea, the R e d Sea and the Gulf Area. H o w e v e r , for a n u m b e r o f years t o c o m e a s o m e w h a t d i f f e r e n t s i t u a t i o n will prevail. T h e i n t e r n a t i o n a l regulations c u r r e n t l y in f o r c e up to J a n u a r y 1972, n a m e l y the I n t e r n a t i o n a l C o n v e n t i o n for the P r e v e n t i o n o f P o l l u t i o n o f t h e Sea o f Oil, 1 9 5 4 , as a m e n d e d in 1 9 6 2 , p e r m i t t e d the discharge into the Medi t e r r a n e a n within 100 miles f r o m coasts o f m i x t u r e s with an oil c o n t e n t equal to n o t m o r e t h a n 100 parts to 1 , 0 0 0 , 0 0 0 parts of the m i x t u r e . B e y o n d 100 miles f r o m coasts t h e r e was no restriction on discharges. Thus tankers c o u l d freely discharge their slops into the M e d i t e r r a n e a n in t w o areas one o f which is situated b e t w e e n Sicily, s o u t h e r n G r e e c e and the coast o f L i b y a and the o t h e r b e t w e e n Crete, C y p r u s and the coast of E g y p t . T h e approxi-
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mate coordinates o f these two areas were, respectively: 3 7°3 0 N 180°30E; 34°00N 15°10E; 32°35N 18°05E, 34°45N 20°45E; and 34°35N 30°20E; 33°15N 26°25E; 33°15N 30°45E. F o r t u n a t e l y , this situation came to an end on 20 January 1978 when the 1969 a m e n d m e n t , prepared and a d o p t e d by IMCO, to the above-mentioned 1954 Convention, as amended in 1962, came into force. Under the terms of the new a m e n d m e n t all discharges whatever their oil c o n t e n t are now prohibited within 50 miles of coasts, and b e y o n d 50 miles from coasts the rate of discharge must n o t exceed 60 1 per mile travelled in the case of ballast water or contain mo r e than 100 parts per million in the case of effluent mixed with oil cargo residues. Lastly, after the International Convention for the Prevention of Pollution f r o m Ships, 1973, also prepared under the auspices of IMCO, comes into force, all discharges of whatever kind will be prohibited in the Mediterranean which for this purpose is designated by the Convention as a "special area".
Accidental pollution on a massive scale
Pollution o f this kind is generally the result of accidents -- groundings or collisions -- involving tankers. The best known example is that of the "Torrey C a n y o n " in March 1967. Such pollution causes serious damage to local marine life and to coastal countries and is a m a t t e r of concern for public opinion. Most accidents are caused by human error. Thus a great deal is now being done in an ef f o r t to improve navigational conditions, in particular by introducing traffic separation schemes in areas of convergence or high traffic density, and to raise the standards of training of sea-going personnel. Although the meteorological conditions are more favourable than in ot her seas -- in spite of f r equent and violent storms in winter -- there is still a risk o f such accidents occurring in the Mediterranean. In order to appreciate the risk t o be faced by coastal countries as a result o f deliberate or accidental pollution, one must bear in mind the influence of winds and currents in the Mediterranean and certain hydrological factors. Away from the coasts, the general wind patterns over the Mediterranean as a whole, d o m i n a t e d by the three "lungs" of the Mediterranean -- the Gulf of Lions, the upper Adriatic and the Aegean -- is characterized by: (1) a prep o n d e r a n c e o f n o r t hw e s t er l y winds between April and September, generally light to moderate; (2) winds blowing both from the nort h and from the n o r t h wes t in October; (3) the lack of any p r e p o n d e r a n t wind from November to January, although winds f r om southwest to northeast, including northwesterlies are more frequent than winds blowing from the opposite semicircle; and (4) fairly f r e que nt gales from January to April.
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METEOROLOGICAL AND OCEANOGRAPHICAL DATA O n l y a t h i r d o f the w a t e r loss in the M e d i t e r r a n e a n as a result o f evaporat i o n is o f f s e t b y t h e i n f l o w o f fresh w a t e r f r o m coastal rivers. The r e m a i n i n g t w o - t h i r d s are m a d e up by the i n f l o w o f water f r o m the Atlantic t h r o u g h the Straits o f Gibraltar. This explains the e x i s t e n c e of an east-going surface c u r r e n t along t h e n o r t h coast of Africa. Part o f t h e c u r r e n t is d e f l e c t e d by Sicily and the s o u t h e r n part o f Italy and flows along the west coast o f Italy and t h e n turns w e s t w a r d along the F r e n c h coast and t h e n s o u t h w a r d o f f the Spanish coast. T h e o t h e r part o f t h e c u r r e n t c o n t i n u e s t h r o u g h the Malta Channel in an easterly d i r e c t i o n along the coasts o f C y r e n a i c a and E g y p t , turns n o r t h w a r d along the coast o f Israel and Syria and t h e n returns westward along the coast o f T u r k e y and n o r t h e r n Crete. T h e c u r r e n t is t h e n j o i n e d b y the surface w a t e r flowing f r o m the Black Sea t h r o u g h the Bosporus, the Sea o f Marmara and the Dardanelles. One b r a n c h o f the c u r r e n t follows the western coast o f G r e e c e and e n t e r s the Adriatic where it flows along the coasts o f Albania and Yugoslavia r e t u r n i n g in the o p p o s i t e d i r e c t i o n along the coast o f Italy. It can t h u s be seen t h a t the general d i r e c t i o n o f the surface circulation in the western basin, as well as in the eastern basin o f the M e d i t e r r a n e a n and in the Adriatic, is c o u n t e r - c l o c k w i s e . Observations m a d e on shipping r o u t e s indicate t h a t the speed o f the curr e n t rarely exceeds a rate o f 1 k n o t and, c o n s e q u e n t l y , its d i r e c t i o n , in the case o f t h e c u r r e n t r e t u r n i n g westward, is subject t o wide local variations as a result o f high winds. T h e m i n i m u m d e e p - w a t e r t e m p e r a t u r e is b r o a d l y similar to the average surface t e m p e r a t u r e in winter. Thus, t h e r e are no vertical c u r r e n t s in t h e M e d i t e r r a n e a n such as w o u l d be caused b y wide differences b e t w e e n the bott o m and surface t e m p e r a t u r e s . T h e masses o f water in c o n t a c t with the a t m o s p h e r e d o n o t circulate rapidly enough t o cause a d e q u a t e o x y g e n a t i o n . It has been e s t i m a t e d t h a t it takes a b o u t 80 years for the mass o f w a t e r b e t w e e n the surface and a d e p t h o f 150 m t o b e c o m e m i x e d and r e - o x y g e n ated. C o n s e q u e n t l y a n y substance t h a t does n o t sink or disintegrate rapidly m a y r e m a i n for a very long t i m e in suspension near the surface or within this layer o f water. This is a very serious m a t t e r in the case o f p o l l u t a n t or n o x i o u s substances. T h e above d a t a m a k e it clear t h a t p o l l u t i o n , f r o m w h a t e v e r source, will n o t be s u b j e c t e d t o such extensive or rapid biological d e g r a d a t i o n as in t h e o p e n seas. Moreover, t h e set o f the prevailing winds and the d i r e c t i o n o f the currents a c c o u n t for t h e serious p o l l u t i o n t h a t occurs in the t w o basins o f the M e d i t e r r a n e a n : (a) on the s o u t h e r n and eastern coasts o f t h e eastern M e d i t e r r a n e a n basin, t o say n o t h i n g o f the large-scale p o l l u t i o n t h a t occurs
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elsewhere, in particular in the Dardanelles, the Aegean and the Adriatic; (b) in the western basin on the coasts of North Africa, Italy, France and Spain. It must be acknowledged, however, that pollution on the coasts of the three last named countries is mainly caused by oil from industrial sources and not from ships.
FUTURE PROSPECTS Assuming that peace prevails in the region, it is reasonable to expect a continuous expansion of maritime traffic in the Mediterranean both for miscellaneous cargoes and for bulk cargoes of dangerous or noxious substances and for oil products. It is likely, therefore, that there will be an increase in the density of commercial shipping and also in certain pollution hazards. Ships will ply the Mediterranean in ever greater numbers between east and west and between north and south in order to satisfy the growing needs of expanding maritime trade particularly with the countries of the Middle East whose economic potential is growing rapidly. The currently planned widening and deepening of the Suez Canal and the putting into service of an oil pipeline from Suez to the Mediterranean (SuMed) in parallel to the Suez Canal are likely to attract through the Mediterranean a substantial proportion of the shipments of oil which at present take the route round Africa. The intersection of increasingly busy shipping routes and the convergence of many such routes in certain areas causing an appreciable rise in traffic density will increase the risks of accidents and collisions in spite of the good visibility which generally prevails in the Mediterranean. The risk of massive and accidental pollution will thus inevitably increase. Admittedly, if present plans to expand the capacity of oil-refining facilities at the place of production are carried out, the transport of such products will present less threat to the marine environment. On the other hand, the increasingly large quantities of dangerous and noxious bulk chemicals will be a more serious environmental hazard. With regard to deliberate and habitual pollution by oil from ships, it is to be hoped that the entry into force of the 1969 amendments to the International Convention of 1954/1962, on the one hand, and of the International Convention of 1973, on the other, will provide a means of eliminating it completely.
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CONCLUSIONS Although n o t as dramatic or even as extensive and serious as pollution from land-based sources, the pollution of the Mediterranean by ships is a m a t t e r on which a t t e n t i o n should be focused and which calls for co-ordinated and co-operative efforts on the part o f the coastal countries and of other countries outside the region whose ships use the Mediterranean either for trade with Mediterranean countries or as a through-route to or from o t h e r regions o f the world. In particular, the countries concerned ought: (a) to make every ef f or t to expedite the entry into force of the International Convention o f 1973, and the Mediterranean countries should, in addition, address themselves to the task, wherever there seems t o be a need, o f establishing the reception facilities for oily wastes specified by the Convention; (b) to co-operate very closely with the Regional Oil-Combating Centre, set up in Malta b y the United Nations E n v i r o n m e n t Programme thanks to the generous hospitality of the G o v e r n m e n t of the Republic of Malta, the operation of which has been entrusted to IMCO; (c) to prepare and adopt, as required, within the fram ew ork of IMCO, schemes f o r the separation of traffic at the points of intersection of transMediterranean routes or in areas with a high traffic density; (d) to compile statistical data on quantities and destinations, and scientific data ,1 on the hazards to the marine envi r o nm ent of cargoes of dangerous and noxious substances transported in bulk; (e) subsequently, insofar as the data thus gathered indicate a need, to ensure, by means of an a m e n d m e n t to the International Convention of 1973, that the Mediterranean is regarded as a "special area" in which any discharge of such substances would be prohibited. Such an a m e n d m e n t would, moreover, make it obligatory for countries bordering the Mediterranean to establish reception stations for wastes and residues o f such substances.
• 1 The Group of Experts on the Scientific Aspects of Marine Pollution (GESAMP) has already begun to work on this task.
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