Today, over half the world lives in cities, and the number is growing. Climate impacts such as heatwaves, floods and extreme weather events are becoming more intense and frequent. Urban areas have been hit hard. As cities look toward increasing their preparedness and capacity to adapt, technologies are offering part of the solution.
From cooling buildings, rainwater harvesting, protecting critical infrastructure to warning residents about a flood, this section showcases some well-established solutions. It also introduces technologies as yet on the horizon, and presents examples of innovative ways of using technology for climate adaptation. Nature-based and engineered solutions all have their important role to play.
Technological developments and trends
Green and resilient cities
High levels of concrete in cities create a thriving environment for water to gather, multiplying the effects of floods and flash floods. Solutions such as permeable roads and drainage infrastructure … Read more
Technological developments and trends
Green and resilient cities
High levels of concrete in cities create a thriving environment for water to gather, multiplying the effects of floods and flash floods. Solutions such as permeable roads and drainage infrastructure offer some relief. But many cities are adapting to climate change consequences by applying nature-based solutions. A typical example is tree use. Trees provide cooling. But they also shade pedestrians, help manage stormwater runoff, improve air quality and stabilize soil structure to mitigate mudslides. Despite all this potential, many cities are reporting urban tree loss. While this highlights a bias favoring hard technologies over natural solutions, there is a growing consensus that nature needs to be reintroduced into urban areas. Adaptation solutions in cities are increasingly designed as multi-functional spaces that provide attractive locations for citizens. Although nature-based solutions can absorb climate impacts to a certain extent, it is clear that buildings, infrastructure and urban services must adapt. Melting roads, buckling railroads and flooded streets block access to public transport. More frequent power outages are also expected, as storms knock trees onto transmission lines, impacting critical services to hospitals, homes and industry. Many service providers and utilities are now planning for climate adaptation and mapping vulnerabilities in their systems.
Adapting buildings to hot and wet conditions
Low-tech solutions for managing heat have sufficed in many regions in the past. They include cross-ventilation, fans, insulation and shading. However, such options are increasingly inadequate due to more extreme heatwaves. This is especially the case for the more vulnerable parts of the world’s population. Reflective and vegetated roofs and facades are growing in popularity. But the installation of air conditioners to manage rising urban temperatures is increasing rapidly worldwide. Their energy use and refrigerant gasses are significant contributors of greenhouse gas emissions. Much innovation is therefore focused on making mechanical cooling systems more efficient. Recent years have seen technological advances in areas such as desiccant cooling and radiative cooling. Technology is also helping to regulate temperatures better in real-time. As many cities become digitized and interconnected, the internet of things (IoT) and sensors in cities can enable smart heating and automated shutters.
Addressing vulnerability of systems
The interconnectedness of urban networks may also exacerbate vulnerability. To avoid this, decentralized infrastructure and services could help remove single points of failure. Distributed water treatment as back-up systems for example allow water to be treated at the point of use during a crisis. Meanwhile, distributed and local storage of water can mitigate risks related to hydropower generation, river flow management and so on. Decentralization may also improve people’s access to new technologies. For early warning systems, it is often imperative to get communities and citizens involved (. Interestingly, technologies not originally intended as adaptation solutions have sometimes been used as such. Examples include social media apps Twitter or Snap Map. Originally intended for sharing opinions or leisure photos, they have also been used for things like citizen mapping of floods in real-time. Cities face varying levels of climate risk. Identifying these risks is key. Engaging schools, religious institutions and community centers in monitoring climate impact indicators could play an important educational role while also complementing authorities' weather monitoring efforts. Read less
Patents and finance
Urban resilience multifaceted
General patent trend assessments in this sector are few. Strengthening the resilience of cities often involves holistic techniques and approaches unsuitable for patenting, for example green space integration in urban planning. Many solutions for … Read more
Patents and finance
Urban resilience multifaceted
General patent trend assessments in this sector are few. Strengthening the resilience of cities often involves holistic techniques and approaches unsuitable for patenting, for example green space integration in urban planning. Many solutions for cities, such as those related to flood defense systems, overlap with technologies presented in the chapter on Water and Coastal regions. For example, surface, ground and rainwater collection represents a major part of water-related technology patents. Water storage is another rapidly growing area of invention, which may reflect the increased risks to water supply.
The heating, ventilation and cooling sector is another key area where patent activity may reflect the climate impact already felt by cities. Efficient and clean energy cooling systems are essential for responding to warmer temperatures in cities. Although more recent patent analysis is needed, a study commissioned by WIPO in 2012 showed a significant increase in patent activity related to solar cooling from 2005 and onwards. Meanwhile, the last 10 years has seen significant patenting activity growth in the field of active cooling (i.e., as an alternative to vapor compression cooling systems). This has mainly been driven by a surge in patenting activity in China. However, conventional technology patents remain dominated by established manufacturers from the United States and Japan. Of the four main cooling technology categories, electro-mechanical and thermally-driven cooling recorded the sharpest growth during the period studied, whereas patent applications for vapor-compression and solid-state technologies saw a more conservative growth (figure 5.1). A recent study highlights magnetic and absorption cooling as promising alternative cooling technologies in these categories.
Adaptation finance gap in cities
There is huge potential in climate-proofing urban infrastructure and services. Up to USD 4 trillion worth of assets are at risk from climate change in cities worldwide. The World Bank has estimated that investing USD 1 trillion in climate-resilient infrastructure in developing countries would generate USD 4.2 trillion in benefits. Managing climate risk in cities and settlements requires a mix of infrastructure, nature-based, institutional and sociocultural interventions. The adaptive capacity of cities can be significantly increased through investments in infrastructure and solutions that are nature-based. However, climate finance toward cities, as in other sectors, tends to focus on mitigation solutions such as low-carbon transport and energy efficiency improvements to buildings. Indeed, under 10 percent of overall climate finance directed toward cities is linked to adaptation and resilience building. This is primarily related to water and wastewater projects, followed by disaster risk management. Furthermore, while many international funds support adaptation measures, there is a large gap in climate finance at city level. This is especially the case in rapidly urbanizing cities in Africa and South Asia.
Infrastructure a top priority
City and local governments remain key actors for facilitating adaptation, as well as public utilities and public services enterprises. Although data access is challenging, it is estimated that urban adaptation funds flow mainly from multilateral development finance institutions, followed by national sources and bilateral support. Multilateral climate funds also play an important role. Overall, investments often focus on hard protection measures and infrastructure. Looking at a selection of developing countries’ most recent adaptation finance needs, infrastructure accounted for 22.6 percent. Private and business sector investments in key infrastructure, housing construction and insurance could help scale action. But they risk excluding the priorities of the poor. Global financing structures too are sometimes ineffective in responding to the needs of the urban poor. Locally managed funds may create better-targeted solutions. Read less
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