각개전투식 방재는 끝났다…‘복합 기후 재난’ 대비해야 [왜냐면]

This summer, South Korea experienced record-breaking heat, followed by drought and heavy rain, causing significant damage. This "complex climate disaster" is not unique to Korea. This summer, Europe suffered from consecutive heatwaves and record-breaking drought, leading to large-scale wildfires. Meanwhile, North America faced overlapping heatwaves and drought, resulting in wildfires.

In South Asia and the Middle East, extreme heat and dry conditions were followed by intense rainfall. Globally, simultaneous occurrences of heatwaves, droughts, wildfires, and heavy rainfall are intensifying. Scientists have warned for some time that such complex extreme weather events will become more frequent. The Intergovernmental Panel on Climate Change (IPCC) reports and latest climate models consistently predict that heatwaves and droughts will become stronger, both simultaneously and sequentially, followed by intense rainfall, leading to a "hydroclimate flash flood" phenomenon.

The current situation is not an unexpected disaster but the result of climate change becoming a reality. The problem is that this complex disaster is qualitatively different from traditional single disasters. When heatwaves, droughts, and rainfall occur separately with time gaps between them, the damage is not simply the sum of individual impacts.

Heatwaves evaporate soil moisture, exacerbating the impact of subsequent droughts. Dry, brittle ground becomes more susceptible to intense rainfall, causing landslides and rapid flooding. Ecosystems lose time for recovery. Crops suffer stress, leading to losses, while power and water supply systems are pressured twice or thrice.

Research shows that these synergistic effects cause far greater damage than the simple addition of individual disasters. Reduced resilience leads to increased vulnerability to future extreme events. However, our response systems still largely adhere to a "one by one" approach, addressing each disaster individually. Weather warnings are issued, urging people to stay cool and conserve water during heatwaves, and to store water for emergencies during rainfall.

But this approach is inadequate in the face of complex disasters. Individuals, local governments, and the central government each have separate disaster manuals. This approach may not be completely ineffective, but it has its limits. During a complex disaster, the assumption that one disaster ends before the next begins is crucial.

People should prepare for multiple disasters and stock non-perishable food and water for 2-3 weeks, as well as emergency power supplies. Evacuation routes should be multiple, and vulnerable populations should simulate overlapping scenarios, such as heat exhaustion during floods. Beyond individual checklists, life habits and emergency plans must account for chain scenarios.

At the societal level, more fundamental transformations are required. Water management should maintain surplus capacity during droughts while preparing for floods. Agriculture should incorporate drought-resistant soil management and crop rotations after droughts and flood-resistant systems. Power grids must be redesigned to handle simultaneous spikes in demand from heatwaves, droughts, and floods.

Evacuation facilities should be versatile spaces suitable for both heat and floods, and barriers should be lowered to handle interconnected risks like "heatwave -> drought -> rainfall." Urban planning should also extend to "sponge city" concepts, integrating measures to mitigate heat islands and increase permeability, as well as maintaining green spaces during all phases of a complex disaster.

Climate change has already transformed our daily lives. The simultaneous occurrence of complex disasters this summer may be just the beginning. If we continue to apply existing single disaster strategies, the damage will only continue to escalate. Individuals must begin preparing in their daily lives, while societies must revise their systems and infrastructure to adopt a "chain" approach, ensuring readiness for a sequence of disasters. This is the path to preserving resilience and preventing even greater crises.