The frequency and intensity of flood events have been increasing recently under the warming climate, with snowmelt floods being a significant part. As an effective manner of simulating snowmelt flood, snowmelt models have attracted more and more attention. Through comprehensive analysis of the literature, this paper reviewed the characteristics and current status of different types of snowmelt models, as well as the different coupling methods of models for runoff generation and confluence. We then discussed key issues in snowmelt modelling, including blowing snow model, frozen ground model, and rain-on-snow model. Finally, we give some perspectives from four aspects: data, model structure, forecast and early warning, and forecast and estimation. At present, most of the snowmelt models do not have blowing snow or frozen ground modules. Explicit consideration of blowing snow and soil freezing/thawing processes can improve the accuracy of snowmelt runoff simulations. With climate warming, rain-on-snow events have increased, but the mechanism of enhanced rain and snow mixed flooding is still unclear, particularly for the mechanism of rain-snow-ice mixed runoff generation. The observation and simulation of rain and snow processes urgently need further study. A distributed physical snowmelt model based on energy balance is an advanced tool for snowmelt simulation, but the model structure and parameter schemes still need further improvements. Moreover, the integration of satellite-based snow products, isotopes, and terrestrial water storage change, monitored by gravity satellites, can help improve the calibration and validation of snowmelt models.

Food production and trade play a fundamental role in the globalized food system. However, the phenomena of decreasing food production and trade interruptions are becoming increasingly common. Currently, there is a lack of simultaneous research on food production and import trade. This study compiles socio-economic environmental data from 146 countries and regions worldwide and employs mobile window and network analysis methods to illustrate how food production quantity influences the social-ecological system. The research findings indicate that in the majority of regions worldwide (102 countries), food demand is met through the local food supply, with a predominant distribution in coastal and inland areas. However, 31% of countries or regions primarily achieve food security through import trade, and many of them are island nations and peninsular countries. This discovery provides valuable insights for understanding the diversity and dependency within the global food system. Based on the impact of food production quantity on the global socio-ecological system network, this study reveals the uneven strengths of connections between nodes and inconsistent connection directions. Building upon these findings, we propose recommendations concerning agricultural policies, human-environment relationships, agricultural transformation, and climate change to help prevent and manage food insecurity risks.