中国科学院院士黄建平：西北干旱区“链式灾害”已成新威胁

Core Viewpoint - The northwest regions of China, traditionally known for drought, are increasingly facing severe rainfall events, leading to a heightened flood risk and a need for improved disaster preparedness [1][2]. Group 1: Changes in Precipitation Patterns - The northwest region is becoming "wetter," but rainfall is increasingly "extreme," with significant increases in precipitation and runoff since the 1980s [2][3]. - Extreme precipitation events have become more frequent, particularly in northern Xinjiang, the Hexi Corridor, and the Longzhong area, with cities like Lanzhou experiencing a notable increase in sudden heavy rainfall events [2][3]. - Global warming is closely linked to these changes, enhancing atmospheric moisture capacity and altering moisture transport pathways, leading to more extreme rainfall in the northwest [2][3]. Group 2: Vulnerability and Risk Factors - The climate vulnerability of northwest cities is characterized by natural conditions that are inherently inadequate, such as concentrated rainfall and weak soil moisture retention, which increase the risk of flooding and geological disasters [4][5]. - Urbanization has exacerbated disaster risk by increasing exposure to hazards and reducing the effectiveness of natural water retention systems [4][5]. - Existing infrastructure often fails to meet the demands of extreme weather events, as many designs are based on historical climate data that do not account for current climate variability [4][5]. Group 3: Forecasting and Monitoring Challenges - Despite improvements in forecasting capabilities, predicting localized extreme rainfall remains a significant challenge due to the complex terrain and sparse observation stations in the northwest [5][6]. - Current forecasting accuracy for short-term precipitation has improved, with over 80% accuracy for short-term forecasts and 90% for heavy rainfall warnings, but localized events still present difficulties [5][6]. Group 4: Recommendations for Disaster Preparedness - A systematic approach is needed to translate climate prediction data into actionable disaster preparedness strategies, including risk assessment, adaptive measures, and dynamic updates to plans [6][7]. - Collaboration between climate scientists and urban planners is essential to enhance urban resilience, though challenges such as data barriers and policy implementation difficulties persist [7][8]. - Future urban planning should prioritize high-risk areas identified through scientific assessments to optimize resource allocation and improve disaster response [11][12].