查看更多>>摘要：The South Asian monsoon is a critical climatic phenomenon that sustains the livelihoods of nearly two billion people, who rely on its rainfall for agriculture, water resources, and economic stability. In this context, this paper reviews the impact of climate change on this crucial system, focusing on its dynamics, variability, and future projections. Based on past studies, this study examines observed changes in rainfall during the second half of the 20th century and compares these changes with model projections for the 21st century. The findings suggest that ocean-land temperature gradients, atmospheric circulation, and regional topography interact intricately to influence monsoon behavior. Rising global temperatures are expected to enhance total rainfall due to increased atmospheric moisture, but concerns remain about the potential weakening of monsoon circulation. This raises the critical question of how the projected increase in atmospheric moisture will impact overall rainfall patterns, including intensity, duration, and timing. Another key finding is the role of aerosols in monsoon variability, leading to the question of how aerosol emissions might influence the variability and dynamics of the South Asian monsoon and how these impacts compare to those of greenhouse gases. Given the current limitations in climate models, observational networks, and data analysis, substantial improvements are needed for more accurate future projections of monsoon variability, particularly in terms of monsoon circulation and extreme weather events. Addressing these challenges will be crucial for developing effective adaptation strategies to mitigate the impact of climate change on the South Asian monsoon and to ensure resilience and sustainability in agriculture, water resources, and the regional economy.
查看更多>>摘要：The last few years have witnessed a series of catastrophic urban flood events across the world. This type of extreme events has become more frequent due to climate change. Numerical modelling provides an indispensable means to support flood risk assessment and management. Simulation of the highly transient flood dynamics induced by intense rainfall requires the use of high-resolution hydrodynamic models. Accurate flood prediction needs proper representation of infiltration and drainage processes in complex urban environments, which requires high-quality soil and drainage data that are not widely available. This paper considers these challenges and explores practical approaches to integrate a high-performance hydrodynamic model with high-resolution topography data and crowd-sourced flood observations to address data gaps and support real-time simulation of urban flooding. The model is applied to reproduce a real-world flood event in the 400 km2 Tyneside metropolitan region in the UK at a 2 m resolution, with solution accuracy confirmed by crowd-sourced data. Different simulation strategies are implemented to reflect the impact of infiltration and drainage on surface flooding. It is demonstrated that infiltration and drainage capacity may be considered using conceptualised mass loss parameters, which produces better results than direct reduction to the rainfall rate. Such an approach offers a practical solution to support high-resolution urban flood modelling in large cities, particularly when essential drainage and soil data are not available.
NETL
NSTL
Elsevier