By Prof. LU Mengqian, Chair of UNESCO SEPRESS Decadal Science Programme

The ongoing strong El Niño event has reset global climate risk benchmarks, unleashing a barrage of unprecedented extreme weather across densely populated Asian megacities. Record heat domes, abrupt torrential downpours, and intensified coastal storm systems have struck urban centres in successive waves. While modern metropolitan management systems have long proven effective in handling conventional climate risks and safeguarding urban operational stability, the rapidly evolving climate reality exposes key limitations in existing city planning and governance frameworks. These established frameworks, tailored for historical climatic conditions, are increasingly misaligned with the accelerating volatility of today’s climate system. Hazards once classified as “exceptional extreme weather” have become recurrent seasonal threats, making adaptive governance upgrading and optimisation an urgent, non-negotiable priority for major cities to build greater resilience.

For decades, urban infrastructure design, disaster response protocols, and municipal risk planning have relied on historical meteorological datasets and stationary climate assumptions. This traditional model has served cities well over decades, underpinning stable urban risk prevention and disaster mitigation amid relatively predictable climatic conditions. However, it faces growing limitations under the combined pressure of long-term global warming and amplified El Niño variability. Recent extraordinary tropical activity clearly illustrates the shifting climate regime: Typhoon Atsani, the 21st typhoon of the year, formed on August 24th. Notably, four typhoons developed successively within just six days — on August 19th, 21st, 22nd, and 24th — marking the first occurrence of “four typhoons coexisting” over the South China Sea and the Northwest Pacific this year. Such clustered, high-intensity typhoon activity represents an atypical and aggressive extreme weather pattern rarely observed in historical records. Contemporary climate hazards are no longer isolated, single-dimensional disasters; they evolve into cascading compound risks: extreme heat triggers systemic power grid overloads, short-duration intense rainfall overwhelms ageing urban drainage networks, and tropical cyclones compound wind damage, storm surge and inland flooding in coastal megaregions. These concentrated, concurrent extreme events far outpace the conventional risk parameters that current urban systems are calibrated for. In this context, traditional post-disaster rescue and emergency management mechanisms, though mature and functional for routine crises, require systematic enhancement to address these interconnected, fast-escalating modern urban climate challenges.

Bridging the widening gap between climate prediction and urban governance practice has therefore become central to further upgrading urban resilience. Advanced climate observation and forecasting systems, as advanced by the SEPRESS decadal initiative, deliver high-precision, real-time hazard monitoring and predictive insights into El Niño-driven climate anomalies, providing powerful scientific support for urban risk management. Notably, existing urban governance institutions have laid a solid foundation for climate risk response through years of accumulated experience and perfected operational mechanisms. The core task ahead lies in targeted institutional optimisation — refining urban zoning, infrastructure investment standards, and cross-administrative coordination mechanisms to fully incorporate dynamic climate variability, so as to match scientific forecasting capabilities with on-the-ground governance execution.

A forward-looking paradigm upgrade is imperative for the continuous improvement of megacity governance. Building on the solid foundation of existing risk management systems, urban climate governance needs to further shift from a dominant reliance on reactive disaster recovery to a balanced model integrating proactive prediction, early prevention and scientific response. Regional climate patterns modulated by El Niño, including multi-year precipitation anomalies and periodic heatwave amplification, should be fully embedded into statutory urban planning standards, complementing the existing risk prevention system to address emerging climate features. For interconnected metropolitan clusters, the mature regional governance cooperation mechanism can be further optimised: as extreme weather systems traverse administrative boundaries freely, unified cross-jurisdictional planning, coordinated early warning deployment, and integrated emergency resource allocation will effectively strengthen the overall synergy of the current urban resilience system.

Equally vital is cross-sector synergy between climate science, urban engineering, and sustainable urban financing. Resilient city development requires more than upgraded physical infrastructure; it demands systematic institutional reform and targeted long-term investment. Translating climate predictive data into actionable municipal policies, and establishing stable financial mechanisms for pre-emptive climate adaptation, will define the resilience of tomorrow’s megacities.

This year’s severe El Niño, characterised by unprecedented clustered typhoon activity and the rare “four-typhoon coexistence” phenomenon over offshore waters, serves as a definitive wake-up call and a valuable comprehensive test for urban climate governance. Rather than negating past governance achievements, it fully reveals the necessity of iterating and upgrading urban governance systems to adapt to rapidly shifting climate conditions. The growing clustering and intensity of extreme weather events — from persistent extreme heat waves to concentrated back-to-back typhoon formation — indicate that we can no longer solely rely on climate experience and governance frameworks of the past. As extreme weather becomes the new normal, science-informed, forward-looking governance optimisation — built upon the solid strengths of current management systems — is not merely a critical climate agenda. It is the core guarantee for consolidating urban public safety, maintaining economic stability, and supporting long-term sustainable development for billions of urban dwellers in high-risk megacity regions.