Contemporary cities face one of the greatest challenges in human history: how to transform the urban environment so that it is not only resilient to the effects of climate change, but also actively contributes to its mitigation. This transformation requires a move from piecemeal solutions to a systemic approach that brings together two key pillars of climate policy: mitigation (reducing greenhouse gas emissions) and adaptation (adapting to the consequences of changes).

Composite Resilience: More than the Sum of the Parts

Traditionally, emissions and resilience have been addressed separately. However, modern research and practice are increasingly promoting the concept of „"compounded resilience". This is an approach where adaptation measures are designed to also serve as drivers of decarbonization. Sources state that applying an integrated approach ensures coherence, creates synergies, increases cost-effectiveness and helps prevent inadequate solutions.

An example is the cities involved in the initiative Covenant of Mayors, committed to an integrated approach to climate change mitigation and adaptation. These cities act as "living laboratories" where new forms of governance are tested, capable of coordinating stakeholders across sectors.

The built environment as a key point of change

In the US and Europe, the building sector is responsible for approximately 30 % to 40 % of total greenhouse gas emissions. The transformation of this sector is challenging due to the low rate of housing renewal – the median age of a house in the US, for example, is 45 years. Retrofitting old buildings is more expensive than implementing measures during new construction, which highlights the need for proactive planning.

Modern strategies include: Nature-based solutions (NBS). NBS in an urban context, such as green roofs, walls and urban forests, fulfill a dual role:

1. Adaptation: They reduce the urban heat island effect through shading and evapotranspiration (evaporation) and capture rainwater.
2. Mitigation: They sequester (store) carbon in biomass and reduce the energy demand of buildings for cooling, thereby directly reducing emissions.

For example, a mature deciduous tree can evaporate 100 to 400 liters of water per day, providing cooling power comparable to several air conditioning units, but without their negative impact on global warming.

Climate migration and spatial planning

Climate risks are already changing the map of human settlement. It is estimated that by 2100, the US alone could be displaced by over 13 million people due to sea level rise. If this migration is unorganized (so-called dispersed migration), it can lead to the emergence of „climate sprawl“ and even an increase in overall emissions in the receiving areas.

The solution is climate-resilient spatial planning, which takes climate change aspects into account in the very composition of the city. Models such as the „city of short distances“ minimize the need for transport, while biocorridors and ventilation corridors ensure air circulation and biodiversity. In Slovakia, these principles are part of the Recovery and Resilience Plan, which emphasizes landscape planning reform and investment in green infrastructure in urban areas.

Governance and Financing: Barriers to Implementation

An analysis of 23 European cities from the second wave of the „100 Climate Neutral Cities“ mission reveals that while ambitions are high (often 80-90 % emissions reduction by 2030), the path to achieving them is fraught with obstacles. The most common barriers include:

• Financial constraints: Almost all cities face problems with mobilizing investment and dependence on external funds.
• Regulatory barriers: National laws often hinder innovative local solutions.
• Lack of data: Many plans suffer from insufficient quantification of emissions in specific sectors.

It is key to success multi-level governance, where cities work together with national authorities and regions. Citizen engagement through climate assemblies or energy communities is also an important element, which increases the social acceptability of the transition.

Innovation in practice: From energy to water

New approaches include not only renewable energy sources (RES), but also circular water management. Installing photovoltaics on public buildings or supporting energy communities decarbonizes the grid and increases energy self-sufficiency. Recycling „"gray water"“ (from sinks and showers) in buildings can replace up to 50 % of drinking water consumption, saving the energy needed for its treatment and transport.

Achieving climate neutrality by 2030 is not just a technical task, but a complex system change that must take into account social justice and economic competitiveness. Cities that invest in „composite resilience“ today will become safe havens in a changing world and leaders of the new green economy. JRi

An analogy for better understanding: Think of a city’s climate policy as building a ship. Mitigation is like fixing the engine so the ship stops emitting toxic substances and slowing global warming. Adaptation is like strengthening the hull so the ship can withstand ever-larger waves and storms. „Composite resilience“ means building a ship so that the strengthened hull also captures wave energy and uses it to power a clean engine. You’re not doing two things at once, you’re doing one thing that solves both problems.

The study was published in the journal springer.com