A drought study in the basin of Lake Urmia under climate change scenarios with higher spatial resolution to understand the resilience of the basin

Abstract

The exposure of the basin of Lake Urmia to meteorological droughts under climate change scenarios is investigated in this study. Should the catastrophic disappearance of the lake be explained by climate change, the basin would not be resilient to droughts in the future. This is examined by a climate change modelling involving downscaling: use 11 general circulation models to provide climate variables downscaled to a high spatial resolution of 57 stations deriving a correlation between observed time series at the base period and climatic variables; projection: derive precipitation at near/far future using the equations; and drought studies: derive 1-month standard precipitation index at the base and near/far future periods. The results identify the following: (i) in the base period, the lowest and highest biases are −2.5 and 3.7 mm, respectively; (ii) in the near/far future periods, the zones are less prone to meteorological droughts in the south, where water is plentiful, but prone in its north, where water is relatively scarce; (iii) the areas are likely to get drier or wetter but their ratios are unlikely to change. This resilience underpins the urge to appropriate policymaking, decision-making, and planning systems to ensure that the basin is made incrementally more resilient. HIGHLIGHTS Spatial drought characteristics of the Standardised Precipitation Index were projected in the basin of Lake Urmia (LU).; Drought duration and severity were estimated by considering the uncertainty of general circulation models.; The results do not identify any drastic drought characteristic in future, and hence the basin is resilient.; The modelling results are strong enough to discern anthropogenic impacts from natural forcing.; The results serve as evidence to underpin the problems of LU to arise from mismanagement.;

Keywords

• downscaling/projection
• lake urmia
• mismanagement
• planning/policymaking
• resilience/vulnerability