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The Aral Sea's degradation has often discouraging examples from elsewhere in now-exposed sediment that sometimes 9 been invoked as a parable: what lessons in the western United States suggest that become airborne. Second, the volume of does the Aral Sea situation hold for other, there are legitimate reasons to worry that a terminal lake is a function of the bal- similar places? One body of water that it may be on a similar trajectory. ance between water inputs from rivers, has much in common with the Aral Sea groundwater and direct precipitation, and 0 is the Great Salt Lake in northern Utah, water outputs from evaporation.' Thus, a located in the heart of the United States' Similarities and Differences reduction in river inflow can push a termi- arid intermountain west. The Great Salt nal lake into a net water deficit, causing Lake is the largest lake in the United Lessons from the Aral Sea are valu- the lake to shrink. As this occurs, any pol- States west of the Mississippi, and the able for the Great Salt Lake because lutants or salts in the water will become fourth-largest saline lake in the world. It the two water bodies are highly compa- more concentrated. This is exactly what is a unique environment, providing refuge rable, beginning with similarities in basic has happened with the Aral Sea as its for vast numbers of migratory waterfowl physical geography. Both water bodies main tributaries, the Amu and Syr Dar'ya, and resident shorebirds, as well as eco- are located in continental interiors, in have been diverted to support irrigation nomically valuable salts and brine shrimp low-lying depressions flanked by high projects further upstream. In some years eggs. Birdwatchers use the parks and mountains (see Figures 1 and 2 on pages in the 1980s, the Aral Sea was receiving wildlife refuges on its shores and islands, 11 and 12). Consequently, the climates of almost no water at all, and by 1989 it had and adventurous recreational opportuni- the two places are similar: broadly dry, shrunk to the point where it had split into ties are available for sailors and kayakers. with large annual temperature ranges and two lakes, the Large Aral and the Small Art aficionados willing to travel to the mountains much cooler and wetter than Aral, with the Large Aral itself now split remote north shore can view and inter- the desert lowlands. into eastern and western basins.'" In the act with the Spiral Jetty, an internation- Both water bodies are fed when mountain same way, the Great Salt Lake's volume is ally famous work of "Earth art" built by snowpack, accumulated over the winter, fundamentally dependent on river inflow, Robert Smithson in 1970.6 Another artist thaws in spring and early summer, deliver- which is in turn a function of winter deeply affected by the lake, author and ing a distinctive pulse of spring meltwater. snowpack. The mountains of Utah have naturalist Terry Tempest Williams, a Utah River flows decline into late summer and some of the most variable snowpack totals native, writes, "Great Salt Lake: wilder- autumn as the snows melt down. in the intermountain west, so the volume ness adjacent to a city; a shifting shoreline The stark differences in thermal and of the Great Salt Lake fluctuates accord- that plays havoc with highways; islands moisture characteristics between the lake ingly (see Figure 3 on page 13).12 too stark, too remote to inhabit; water in and surrounding land surfaces mean that Differences between the lakes are gen- the desert that no one can drink. It is the the Aral Sea and the Great Salt Lake both erally of degree rather than kind. The 7 liquid lie of the West.'" influence their local climates, moderating Great Salt Lake, for example, is smaller, Because the Great Salt Lake shares with annual and diurnal temperature ranges shallower, and much saltier than the Aral the Aral Sea particularly striking similari- and providing a moisture source for pre- Sea. Salinity for parts of the Large Aral ties in terms of climatic and hydrological cipitation. This is evident in lake-effect may now be above 10 percent, while the characteristics, the Aral Sea can shed snowstorms downwind of the Great Salt partly rehabilitated Small Aral is around 1 3 light on the future water management Lake, for example, and in the climatic percent.1 Salinity of the main (south) arm challenges facing the Great Salt Lake effects of the shrinking of the Aral Sea, of the Great Salt Lake, Gilbert Bay, aver- in response to population growth and a which has caused local annual tempera- ages around 14 percent, but this fluctuates likely regional climate shift toward drier ture ranges to increase by up to nearly enormously with lake level, from 26-28 conditions. The Great Salt Lake is not 11°F between 1960 and 1997, according percent when the lake was at its lowest alone in the western United States in to one estimate.8 recorded level in 1963 to 6-9 percent facing this combined squeeze on water As lakes in the desert, the Aral Sea when it reached its highest in 1986.1" resources from increased demand and and the Great Salt Lake share one more The Great Salt Lake's generally very decreased supply. Could it become an important feature: both are terminal lakes, high salinity makes for a simpler ecosys- icon of twenty-first century American with no outlet to the sea. This has two tem than that of the (originally) brackish water problems in the same way that the important consequences. First, pollutants Aral Sea because few species can toler- Aral Sea became an icon of global water can accumulate in terminal lakes, reach- ate such harsh conditions. Phytoplankton problems in the twentieth century? The ing concentrations that pose a hazard to (Dunaliella viridis and others) provide Great Salt Lake is not yet comparable wildlife and human health. For instance, food for brine shrimp (Artemia francis- to the Aral Sea in terms of environmen- in the Aral Sea basin, agricultural chemi- cana) and brine flies (genus Ephydra), tal degradation. However, future water cals used on the cotton fields have been which in turn provide food for resident and 5 management challenges, a local tendency carried by irrigation runoff into the lake, migratory birds." Halophilic bacteria also to undervalue the Great Salt Lake, and where they have accumulated over decades occupy the lake, imparting a reddish tinge 10 ENVIRONMENT WWW.ENVIRON M ENTMAGAZIN E.ORG VOLUME 51 NUMBER 5 w-| | SEPTEMBER/OCTOBER 2009 WWW.ENVIRONMENTMAGAZIN E.ORG ENVIRONMENT 11 1 1.) UU W 113~~~~IL )1VU W 1~UtlL VUV z b b z b z b z 0 b 112 3VO-W t1z"IW Lake, Level Elevation In Feet Utah's Great 4f91 - Historic Low 1963 I Rivers Salt Lake and 4200 - Average ----- Railroad Causeway 4212 - Historic High 198O Road Causeways Environs 12 ENVIRONMENT WWW. ENVIRONM ENTMAGAZIN E.ORG VOLUME 51 NUMBER 5 a broadly freshwater ecosystem, and, in years of very high lake levels, the lower salinities in the main body of the Great Salt Lake allow for greater species diversity and more predation of brine shrimp.16 The dynamics of the Great Salt Lake ecosystem are of great interest to Utah's multimillion- dollar brine shrimp industry, which har- vests brine shrimp eggs for sale to com- 7 mercial aquaculture operations.' Both lakes serve as important oases for wildlife, especially migratory birds. The Great Salt Lake's simple ecology provides abundant food, and its harsh, high-salinity environment deters preda- tors. Consequently, huge numbers-liter- ally millions-of birds use the Great Salt Lake as a refueling stop on their journey between nesting grounds in Canada and the United States and wintering grounds in Mexico and South America. It is dif- ficult to overstate the importance of the Great Salt Lake in this context. For exam- ple, the migratory population of Eared In 1989, the Aral Sea split into two lakes, the northernSmall Aral and southern Large Aral Grebes at the Great Salt Lake represents (left), which is now further split into western and eastern basins. The eastern basin in around half particularis rapidly drying out, as shown in a satellite image from 2008 (right). of the North American total; populations of American White Pelican, White-Faced Ibis, and California Gull are among the largest in the world; and the population of Wilson's Phalarope at the Great Salt Lake in July often constitutes more than a third of the world's total."8 In addition to sheer numbers of birds, the Great Salt Lake's location as a link in the chain of north-south bird migration makes it important not just nationally, but hemi- spherically, qualifying it as a site in the Western Hemisphere Shorebird Reserve Network.19 The wetlands of the Aral Sea, in the Amu and Syr Dar'ya deltas, have his- torically played a similar role for water- birds flying from western Siberia and Kazakhstan to spend the winter in south- west Asia, Africa, and India, returning in northern hemisphere summer.20 The environmental degradation of the Aral Sea itself has reduced its role as a migratory stopover, and birds now instead appear to be using the artificial lakes and wetlands afforded by the network of reservoirs on to the saltiest locations. However, gener- sive to spatial and temporal changes in the Amu and Syr Dar'ya. The different alizations are difficult because this appar- salinity. Near the inflow of the Bear River, salinities of the Great Salt Lake and the ently simple ecosystem is highly respon- for example, the Great Salt Lake maintains "original" Aral Sea suggest this transition SEPTEMBER/OCTOBER 2009 WWW.ENVIRONMENTMAGAZI NE.ORG ENVIRONMENT 13 would be unlikely to be replicated at the 2 Great Salt Lake.

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