Data file for baseline analysis.

Billions of people globally are at risk for severe water scarcity periodically throughout the year. Moreover, intensifying climate change and increasingly unpredictable weather patterns will increase the severity and scope of those affected by household water insecurity, with negative consequences on household health and wellbeing. Faced with water insecurity, households shift to alternative water sources, which may be more expensive or of lower quality and contribute to both financial and health burdens. The extent to which household water insecurity varies throughout the year, however, remains understudied. Using a panel dataset of 2014 households across 40 villages in Matlab, Bangladesh, we test for seasonal variation in household water insecurity and its determinants using a modified HWISE scale. We find that while water insecurity in Matlab was low both pre- and post-monsoon, household water experiences vary throughout the year. Households report significantly lower water insecurity post-monsoon, compared to pre-monsoon, suggesting an annual measure of household water insecurity is insufficient to fully characterize intra-annual household water experiences. Comparing determinants of household water insecurity, we find that geography, household water use behaviors, and household characteristics are significantly related to experiences of household water insecurity but vary in their extent depending on the season. Our results demonstrate that physical location, seasonality, water quality, and household-level factors contribute to the dynamic nature of intra-annual household water insecurity. Knowing when and to what extent such determinants influence household water experiences throughout the year is essential for guiding and adapting engineering and policy design to reduce the costs and consequences of household water insecurity.

全球范围内，数十亿人口全年周期性面临严重水资源短缺风险。此外，加剧的气候变化与愈发难以预测的天气模式，将扩大受家庭用水不安全影响的人群范围、加重其危害程度，并对家庭健康与福祉造成负面影响。面对用水不安全问题，家庭往往会转向替代水源，这类水源通常成本更高、水质更差，进而给家庭带来经济与健康双重负担。然而，家庭用水不安全程度在年内的波动幅度，目前仍未得到充分研究。本研究依托孟加拉国马特拉巴（Matlab）40个村庄共计2014户家庭的面板数据集，采用改进版家庭用水不安全评估量表（HWISE scale），检验家庭用水不安全的季节差异及其影响因素。研究结果显示，尽管马特拉巴地区季风前后的用水不安全程度均处于较低水平，但家庭的用水体验全年存在显著差异。相较于季风前期，家庭在季风后期的用水不安全程度显著更低，这表明仅用年度指标衡量家庭用水不安全状况，无法全面刻画年内家庭的用水体验。通过对比家庭用水不安全的影响因素，我们发现地理区位、家庭用水行为与家庭特征均与用水不安全体验显著相关，但其影响程度随季节变化而有所差异。本研究结果表明，地理区位、季节节律、水质状况与家庭层面因素共同塑造了年内家庭用水不安全的动态特征。明确上述影响因素在全年何时、以何种程度影响家庭用水体验，对于优化工程设计与政策制定、降低家庭用水不安全带来的成本与危害至关重要。