Singapore ,1 MDB,a change of leadership & the water agreements:Are the agreements so fraught with uncertainty that there could not have been a real agreement in the first place?
by Ganesh Sahathevan In a paper titled Impacts and uncertainties of climate change on streamflow of the Johor River Basin researchers in Malaysia and the US concluded that their modelling showed climate could " lead to a projected annual streamflow ranging from 0.91 to 12.95% compared to the historical period."
It is likely that the Malaysia-Singapore Water agreements were based on historical flows that did not account for any future change in annual streamflow. Then, it is arguable that there could have been a contract or agreement at all, for all sides would have laboured under a false or incorrect factual basis.Put in other words, you cannot have a contract over something you assume will remain constant when it is in fact be subject to change.
While this is only one study and its findings may well be disputed, it does raise the matter of uncertainty which appears to have been ignored. As previously mentioned,
The impact of climate change and uncertainty of climate projections from general circulation models (GCMs) from phase 5 of the Coupled Model Intercomparison Project (CMIP5) on streamflow in the Johor River Basin, Malaysia was assessed. Eighteen GCMs were evaluated, and the six that adequately simulated historical climate were selected for an ensemble of GCMs under three Representative Concentration Pathways (RCPs; 2.6 (low emissions), 4.5 (moderate emissions) and 8.5 (high emissions)) for three future time periods (2020s, 2050s and 2080s) as inputs into the Soil and Water Assessment Tool (SWAT) hydrological model. We also quantified the uncertainties associated with GCM structure, greenhouse gas concentration pathways (RCP 2.6, 4.5 and 8.5), and prescribed increases of global temperature (1–6 °C) through streamflow changes. The SWAT model simulated historical monthly streamflow well, with a Nash–Sutcliffe efficiency coefficient of 0.66 for calibration and 0.62 for validation. Under RCPs 2.6, 4.5, and 8.5, the results indicate that annual precipitation changes of 1.01 to 8.88% and annual temperature of 0.60–3.21 °C will lead to a projected annual streamflow ranging from 0.91 to 12.95% compared to the historical period. The study indicates multiple climate change scenarios are important for a robust hydrological impact assessment.