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ARAL , a lake or inland sea in the west of Asia, situated between lat. 43 30' and 46 51' N., and long. 58 13' and 61 56' E. It was known to the ancient Arab and Persian geographers as the Sea of Khwarizm or Kharezm, from the neighbouring district of the Chorasmians, and derives its present namefrom the Kirghiz designation of Aral-denghiz, or Sea of Islands. In virtue of its area (26,233 sq.m.) it is the fourth largest inland sea of the world. It has nearly the same length as width, namely about 170 m., if its northern gulf (Kichkineh-denghiz) is left out of account. Its depth is insignificant, the maximum being 220 ft. in a depression in the north-west, and the mean depth only 50 ft., so that notwithstanding its area it contains only eleven times as much water as the Lake of Geneva. Its altitude is 2422 ft. above the Caspian, i.e. about 155 ft. above the ocean. The lake is surrounded on the north by steppes; on the west by the rocky plateau of Ust-Urt, which separates it from the Caspian; on the south by the alluvial district of Khiva; and on the east by the Kyzyl-kum, or Red Sand Desert. On the north the shores are comparatively low, and the coast-line is broken by a number of irregular bays, of which the most important are those of Sary-chaganak and Paskevich. On the west an almost unbroken wall of rock extends from Chernychev Bay south-wards, rising towards the middle to 500 ft. The southern coast is occupied by the delta of the Oxus (Jihun, Amu-darya), one of the arms of which, the Laudan, forms a swamp, 8o m. long and 20 broad, before it discharges into the sea. The only other tributary of any size that the sea receives is the Jaxartes (Sihun, Syr-darya) which enters towards the northern extremity of the east coast, and is suspected to be shifting its embouchure more and more to the north. This river, as well as the Amu, conveys vast quantities of sediment into the lake; the delta of the Syr-darya increased by 134 sq. m. between 1847 and 1900. The eastern coast is fringed with multitudes of small islands, and other islands, some of considerable size, are situated in the open towards the north and west. Kug-Aral, the largest, lies opposite the mouth of the Syr-darya, cutting off the Kichkinehdenghiz or Little Sea. The next largest island is the Nikolai, nearly in the middle. Navigation is dangerous owing to the frequency and violence of the storms, and the almost total absence of shelter. The north-east wind is the most prevalent, and sometimes blows for months together. The only other craft, except the steamships of the Russians, that venture on the waters, are the flat-bottomed boats of the Kirghiz.
In regard to the period of the formation of the Aral there were formerly two theories. According to Sir H. C. Rawlinson (Prot. Roy. Geog. Soc., March 1867) the disturbances which produced the present lake took place in the course of the middle ages; while Sir Roderick Murchison contended (Journ. of Roy. Geog. Soc., 1867, p. cxliv. &c.) that the Caspian and Aral existed as separate seas before and during all the historic period, and that the main course of the rivers Jaxartes and Oxus was deter-mined in a prehistoric era. The former based his opinion largely on historical evidence, and the latter trusted principally to geological data. There is no doubt that in recent historical times Lake Aral had a much greater extension than it has at the present time, and that its area is now diminishing. This is, of course, due to the excess of evaporation over the amount of water supplied by its two feeders, the Amu-darya and the Syrdarya, both of which are seriously drawn upon for irrigation in all the oases they flow through. Old shore lines and other indications point to the level of the lake having once been 50 ft. above the existing level. Nevertheless the general desiccation is subject to temporary fluctuations, which appear to correspond to the periods recently suggested by Eduard Bruckner (b. 1862); for, whereas the lake diminished and shrank during 1850-1880, since the latter year it has been rising again. Islands which were formerly connected with the shore are now some distance away from it and entirely surrounded by water. More-over, on a graduated level, put down in 1874, there was a permanent rise of nearly 4 ft. by 1901. The temperature at the bottom was found (1900-1902) by Emil Berg to be 33.8 Fahr., while that of the surface varied from 44.50 to 80.5 between May and September; the mean surface temperature for July was 75. The salinity of the water is much less than that of the ocean, containing only 1.05 % of salt, and the lake freezes every year for a great distance from its shores. The opinion that Lake Aral periodically disappeared, which was for a long
time countenanced by Western geographers, loses more and more probability now that it is evident that at a relatively recent period the Caspian Sea extended much farther eastward than it does now, and that Lake Aral communicated with it through the Sary-kamysh depression. The present writer is even inclined to think that, besides this southern communication with the Caspian, Lake Aral may have been, even in historical times, connected with the Mortvyi Kultuk (Tsarevich) Gulf of the Caspian, discharging part of its water into that sea through a depression of the Ust-Urt plateau , which is marked by a chain of lakes (Chumyshty, Asmantai). In this case it might have been easily confounded with a gulf of the Caspian (as by Jenkinson). That the level of Lake Aral was much higher in post-Pliocene times is proved by the discovery of shells of its characteristic species of Peden and Mytilus in the Kara-kum Desert, 33 M. south of the lake and at an altitude of 70 ft. above its present level, and perhaps even up to 200 ft. (by Syevertsov).
The fish of Lake Aral belong to fresh-water species, and in some of its rapid tributaries the interesting Scaphirhynchus, which represents a survival from the Tertiary epoch, is found. The fishing is very productive, the fish being exported to Turkestan, Mery and Russia. The shores of the lake are uninhabited; the nearest settlements are Kazala, 55 M. east, on the Syr, and Chimbai and Kungrad in the delta of the Amu.
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