Strategic decision-making on long-term drought risk management can be supported by integrated assessment models to explore uncertain future conditions and potential policy actions. Such models have to meet many – sometimes conflicting – requirements posed by policy-makers, model developers, and stakeholders. This paper discusses the case of the National Water Model (NWM) that is applied for national policy-making on drought risk management in the Netherlands. The case demonstrates that the chosen assembled model set-up (in which several existing models are combined) is cost-effective and increases stakeholder acceptance, but also leads to high model complexity and computation time. To be effective for policy-making, integrated assessment models need to produce relevant model outcomes that are accepted by stakeholders, within acceptable time and cost limits. For this, the model set-up must support simulations at different aggregation levels (allowing both detailed analysis and exploratory analysis of many scenario/strategy combinations) while maintaining internal consistency.

综合评估模型可以支持关于长期干旱风险管理的战略决策，以探索不确定的未来条件和潜在的政策行动。此类模型必须满足政策制定者、模型开发者和利益相关者提出的许多（有时是相互冲突的）要求。本文讨论了国家水资源模型 (NWM) 的案例，该模型应用于荷兰干旱风险管理的国家政策制定。该案例表明，所选择的组装模型设置（其中组合了多个现有模型）具有成本效益并提高了利益相关者的接受度，但也会导致模型复杂性和计算时间高。为了有效地制定政策，综合评估模型需要产生利益相关者接受的相关模型结果，在可接受的时间和成本范围内。为此，模型设置必须支持不同聚合级别的模拟（允许对许多场景/策略组合进行详细分析和探索性分析），同时保持内部一致性。