Climate-informed environmental inflows to revive a drying lake facing meteorological and anthropogenic droughts

Abstract

The rapid shrinkage of Lake Urmia, one of the world's largest saline lakes located in northwestern Iran, is a tragic wake-up call to revisit the principles of water resources management based on the socio-economic and environmental dimensions of sustainable development. The overarching goal of this paper is to set a framework for deriving dynamic, climate-informed environmental inflows for drying lakes considering both meteorological/climatic and anthropogenic conditions. We report on the compounding effects of meteorological drought and unsustainable water resource management that contributed to Lake Urmia's contemporary environmental catastrophe. Using rich datasets of hydrologic attributes, water demands and withdrawals, as well as water management infrastructure (i.e. reservoir capacity and operating policies), we provide a quantitative assessment of the basin's water resources, demonstrating that Lake Urmia reached a tipping point in the early 2000s. The lake level failed to rebound to its designated ecological threshold (1274 m above sea level) during a relatively normal hydro-period immediately after the drought of record (1998)(1999)(2000)(2001)(2002). The collapse was caused by a marked overshoot of the basin's hydrologic capacity due to growing anthropogenic drought in the face of extreme climatological stressors. We offer a dynamic environmental inflow plan for different climate conditions (dry, wet and near normal), combined with three representative water withdrawal scenarios. Assuming effective implementation of the proposed 40% reduction in the current water withdrawals, the required environmental inflows range from 2900 million cubic meters per year (mcm yr −1 ) during dry conditions to 5400 mcm yr −1 during wet periods with the average being 4100 mcm yr −1 . Finally, for different environmental inflow scenarios, we estimate the expected recovery time for re-establishing the ecological level of Lake Urmia.

Climate change or irrigated agriculture – what drives the water level decline of Lake Urmia

“…The reasons behind the pronounced water level decline during the past two decades are controversial. Several studies state that the reduction of surface water inflow due to agricultural extraction predominantly caused the lake level decline [14][15][16][17][18][19][20][21][22] . This was mainly triggered by an uncontrolled growth of the irrigated area, accompanied by the extensive construction of reservoirs, and poor agricultural water use efficiency.…”

In Water‐Limited Landscapes, an Anthropocene Exchange: Trading Lakes for Irrigated Agriculture

“…Among Earth's terminal lakes this analysis identifies the Aral Sea as having experienced the most extensive areal shrinkage (Figure 2) “overwhelmingly” due to increases in agricultural area (Micklin, 1988; Micklin, 2007; Micklin, 2016), which have continued despite the Sea's rapid shrinkage (Chen et al, 2018). Also in Asia, the shrinkage of Lake Urmia, Iran, has been contested, with claims of the importance of climatic factors discredited relative to overexploitation for irrigated agriculture (AghaKouchak et al, 2015; Alborzi et al, 2018; Chaudhari et al, 2018; Fazel et al, 2017; Ghale et al, 2018; Khazaei et al, 2019; Madani, 2014; Madani et al, 2016; Taravat et al, 2016; Tourian et al, 2015). In North America, agricultural water consumption is identified as the primary driver of shrinkage of the Great Salt Lake, Utah, though secondary factors include mineral production and municipal and industrial uses; reservoir evaporation impacts on the lake water balance exerted only a tertiary impact (Wurtsbaugh et al, 2017).…”

“…The government of Israel has discussed the possibility of desalinating Mediterranean Sea water to increase freshwater availability in the basin of the shrinking Lake Kinneret, a solution with a heavy recurrent price tag, large cost in carbon emissions (Tal, 2018), and a range of environmental impacts (Elimelech & Phillip, 2011) that is complicated by the transboundary nature of the Jordan River basin (Wine, 2019a; Wine, 2019c; Wine, 2019e). In the Lake Urmia basin a 40% reduction in water consumption is recommended to partially refill the lake (Alborzi et al, 2018), though the socio‐economic and political feasibility of choosing to allocate water to natural systems over humans at a large scale in the face of water scarcity remains unproven. Water transfer projects (Shumilova et al, 2018) could also be used to avert negative water balance in inland waters.…”

“…4 at a multi‐decadal to centurial time scale, seasonal and interannual climate variability are likely to exert a minimal influence on ∆S WS . In the context of shrinking lakes, there is a large body of evidence demonstrating that anthropogenic climate change remains a background condition to and not a primary driver of global lake shrinkage (AghaKouchak et al, 2015; Alborzi et al, 2018; Ashraf et al, 2017; Ashraf et al, 2018; Chaudhari et al, 2018; Fazel et al, 2017; Hassani et al, 2020; Khazaei et al, 2019; Madani et al, 2016; Micklin, 1988; Micklin, 2007; Moore, 2016; Morin et al, 2018; Rodell et al, 2018; Wine, Null, et al, 2019; Wine, Rimmer, & Laronne, 2019; Wine & Davison, 2019; Wurtsbaugh et al, 2017). Though not featured prominently here, those lakes influenced by enhanced glacial melt may present an exception to this generalization.…”

Untangling global change impacts on hydrological processes: Resisting climatization

“…This ideal of high-quality objective science indeed underpins the rational discourse to which democracies aspire (Kirchner, 2017). Water managers rely on the science of global change hydrology to secure the water requirements of humans, industry, and ecosystems now and in the future (Alborzi et al, 2018;Gleick, 1989;Grimm et al, 1997;Oki & Kanae, 2006). In transboundary watersheds, climate change may impact available water and, consequently, water sharing (Cooley & Gleick, 2011;Petersen-Perlman, Veilleux, & Wolf, 2017;Wine, 2019b;Wine, 2019c;Wine, 2019d) including in regions already subject to severe water stress.…”