Climate change

In an architecturally important area of Berlin, situated between the Landwehr Canal, the Kulturforum (the Berliner Philharmonie and the Berlin State Library) and the new construction on Potsdamer Platz, a combination of green and grey infrastructure has been realised to minimise the burden on Berlin’s existing water infrastructure.
Green and non-green roofs harvest annual rain, which flows through the site’s buildings and is used for toilet flushing, irrigation, and fire systems. The roofs retain and then release water to the large on-site buffer pond, which has five underground storage tanks. Next to the roofs, a series of urban ponds and connecting canals have been implemented, with a combined area of approximately 1.2 hectares. They are filled with rainwater, creating an oasis for urban life. Vegetated biotopes are integrated into the overland landscape and serve to filter and circulate the water that runs along streets and walkways. The lake’s water quality is excellent, forming a natural habitat for animals and cooling the surroundings, while fresh water usage in the buildings has been reduced. (Ref. 1; Ref. 2; Ref. 3; Ref. 6)
The project was implemented in the 1990s as part of the development of Potsdamer Platz in the wake of the reunification of Germany. Several architects collaborated on the implementation that was completely privately funded. Beyond its ecological and technical features, the site is a blue natural site in the heavily built city centre of Berlin and allows people to linger and enjoy natural features. The drainage system won several sustainability prices and is considered a successful integration of nature and technology-based mechanisms to foster climate change adaptation. As the rainwater system stores rainwater in underground tanks and ponds, the urban sewage system is relieved during heavy rain, and water can evaporate. Therefore, the small water circle is closed, and the microclimate is cooled. (Ref. 2; Ref. 6)

The Green and Blue Axis (Eixo Verde e Azul, EVA) is an inter-municipal green corridor project connecting the municipalities of Sintra, Oeiras, and Amadora through a 15-kilometre green ecological axis along the Jamor River (Ref 2). It aims to renaturalize the river, improve water quality, and control flooding while promoting sustainable mobility through pedestrian and cycling routes (Ref 5). The project also enhances public access to green spaces and cultural heritage sites, such as the Queluz National Palace (Ref 6). EVA supports the Lisbon Metropolitan Area’s regional strategy for climate change adaptation, risk prevention, and low-carbon economy (Ref 4). Funded by the European Regional Development Fund and municipal budgets, the project has an overall investment of €11 million (Ref 1). EVA exemplifies inter-municipal cooperation, overcoming policy conflicts to achieve shared environmental, social, and economic goals, making it a model for integrated territorial development (Ref 4). The project’s long-term impact includes reduced carbon footprint and increased territorial cohesion.

Located in the Lima district of San Isidro - the heart of commercial activity in Peru - the Real Dos Tower is a prime office building in the Centro Empresarial Real de San Isidro. It was inaugurated in 2018, and it is distributed over 23 levels (14 floors and 9 basements) and enjoys a landscaped green roof (1162 m2) at the crown of the building and numerous outdoor vertical gardens at full height (2365 m2) on the three main fronts (1, 4). This project was a finalist in the 2018 Mipim Awards, considered the ‘Oscars’ of world architecture, and stood out for its architecture and design, due to its attributes of innovation and sustainability (2).
This building has managed to create harmony between design and efficient use of resources. It is characterised by a glass façade with colourful movable shutters and symbolic Peruvian designs (2, 3, 6). It has green walls on the three main fronts, four daylight fronts and a roof garden (2). The architect, Jean Nouvel, worked together with ARVE Peru on the overall landscape plans for the Real Dos tower (1, 3).
This is part of the façade remodelling project of the Camino Real Towers in the Real Business Centre, led by the real estate company Grupo Centenario (1, 2, 3, 4, 5, 6). This overarching Project has sought to develop 4,475 m2 of vertical gardens and roof gardens, which have a technified irrigation system to generate efficiencies in water use, meeting the plants' water requirements in the different seasons of the year. Their implementation helps to filter CO2 and renew the O2 in the office complex.
The ARVE group describes these actions as conducive to creating thermal barriers and sound insulation, a better environment for rest, work and entertainment and increasing property value (7)

In 2020, the Metropolitan City of Cagliari launched a project to enhance flood resilience and ecological integrity in the Mannu-Cixerri river system in southern Sardinia. The river traverses several communes within the metropolitan area, ultimately feeding into the Santa Gilla Lagoon, a vital wetland ecosystem west of the city.
The project, with a budget of €21 million, focuses on three key communes: Assemini, Decimomannu, and Uta. Rather than solely emphasizing structural flood defenses, the initiative integrates nature-based solutions (NbS) to mitigate flood risks while restoring riverine ecosystems. The Metropolitan City of Cagliari, in collaboration with the Sardinian Regional Public Works Department, is responsible for its implementation.
Key interventions include reinforcing and revegetating embankments, improving water flow along the Rio Mannu, and constructing new levee sections in a manner that enhances natural water retention. Additionally, the project involves upgrading bridges to facilitate better floodwater management. These measures align with the Sardinian Flood Risk Management Plan (PGRA) and aim to reduce flood hazards while promoting ecological benefits.
The project timeline began with a two-year preparation phase for the Preliminary Design Document, followed by a year-long tendering process for construction. These efforts represent a crucial step toward long-term flood resilience and environmental sustainability in the region. (Ref. 1, 2, 3)

The Metropolitan Linear Park is a project initiated by the national government of Bolivia, funded by the Inter-American Development Bank (IDB) (1-8). The proposed park will be located along a disused railway corridor between the cities of La Paz and El Alto, spanning 18.2 km (8, p. 8). The project involves the construction of a linear park, divided into five sections, each with distinct objectives, uses, and designs (8, p. 9). This large-scale initiative aims to improve access to public spaces in La Paz and El Alto, enhance connectivity between the two cities, protect surrounding biodiversity and natural spaces, and strengthen resilience to and mitigate the effects of climate change (3 & 8, pp. 11-12).
To achieve these goals, the project design includes outdoor sports and recreational facilities, pedestrian and cycling circuits, as well as the restoration of parks, squares, and public spaces adjacent to the park corridor (8, p. 9). Some features include balcony corridors, flower and food-producing urban gardens, and viewpoints (5). The project also plans for the re-vegetation of the area with native species and aims to stop the environmental degradation of surrounding natural environments, such as the Pura Pura forest, which has been suffering from ongoing deforestation and waste dumping (8, p. 9). These efforts are expected to increase and support biodiversity in the area (7 & 8, p. 12).
Additionally, the project emphasizes social inclusion, with policies designed to incorporate women, indigenous populations, and persons with disabilities (8, pp. 7-8). The park is intended to raise awareness about climate change and biodiversity, ultimately improving the quality of life and health of nearby residents and the citizens of La Paz and El Alto (8, p. 13).

A new park is being planned for the Cypress Shores area in Mobile (Ref 1). Five civil engineering students from the University of South Alabama contributed to the design of the park (Ref 1). This collaboration offers students practical experience while providing city designers with innovative ideas for the site (Ref 2). The design emphasizes sustainability and cost-effectiveness (Ref 3). The project will feature a small park and boat launch on a 5.6-acre plot (Ref 1) located within a residential neighbourhood (Ref 3).
The park's societal goal is to improve public access to Halls Mill Creek, giving the community a new way to enjoy the waterway, and this focus aligns with the Mobile Bay National Estuary Program (MBNEP) goals (Ref 3). Historically, the property was used as a shipyard with a nearby railroad crossing (Ref 1), marking its transition from an industrial site to a public park.
Several amenities have been identified for the park’s development, including a boat ramp and kayak launch, a boardwalk adapted to sea-level rise, a pavilion and gazebo designed for flood resilience, a wetland nature trail with solar lighting and educational signage, and composting toilet restroom facilities (Ref 3). An armoured shoreline will be implemented to withstand medium water currents, and wave action will be constructed. Additionally, a living shoreline will be restored with local plants (Ref 3). While the project is still in its preliminary design phase, the timeline for completion is estimated at 12 to 18 months (Ref 1). The designers highlighted a potential trade-off, noting that an influx of visitors to the park could disturb the surrounding residential area (Ref 3).

Seaweeds are of immense value to marine ecosystems, and Kelp, the largest of them all, forms spectacular underwater forests that provide habitat for fish, clean the water, and sequester carbon. Unfortunately, large swathes of these subaquatic forests have disappeared from the coasts of many European countries, including Portugal (Ref. 2).
The "Sea Forester" project in Cascais aims to restore local kelp forests, which are essential for marine biodiversity and carbon sequestration. In collaboration with the Câmara Municipal de Cascais and Mossy Earth (social enterprise), the project assesses the historical and current state of seaweed populations and identifies environmental stressors. It employs innovative techniques like the "green gravel" method to restore kelp ecosystems. This project supports the region’s blue economy and resilience to climate change through carbon offsetting and enhanced ecosystem services (Ref 1; 6; 7). Supported by the EEA Innovation Grant, it combines scientific research and community engagement, positioning Cascais as a leader in marine conservation efforts (Ref 6).

Alexandria is one of the vulnerable cities facing climate change (1). From rising sea levels, pollution, extreme rise and fall in temperature and the urban heat island effect, Alexandria is battling significant challenges (1). The city is also worldly renowned for it beaches and gardens that act as the lungs through which the city breathes, and are considered a haven for its people (1). Unfortunately, in the last ten years, there has been a decrease in parks and green areas, which is a cause for concern (1). This shrinkage comes at the expense of urban expansion and the establishment of Commercial and profitable projects, which is a challenge facing the environmental balance and cultural heritage of the city (1). To address the nature of the challenges and climate changes and their effects in Egypt, the president launched the "The 100 Million Trees Initiative" was brought into action in 2022 as part of the Egypt 2030 Vision (2-3). The campaign is meant to double the per capita share of green spaces across the country, improve air quality and people’s health, and reduce greenhouse gases. It will also aim to recoup economic benefits from the trees, including wood and olive oil (3). As part of this initiative, the governor of Alexandria was tasked with taking care of the green spaces and improving the aesthetic and civilizational level, within the scope of Alexandria's neighborhoods and centers (4). In 2023, the gardens department carried out the planting of 812 trees and shrubs of various types within the scope of Al-Muntazah 2 Neighborhood during Week 25 to continue the work of the presidential initiative to plant 100 million trees in the governorate's neighborhoods (4).

The Stora Amundö and Billdal archipelago nature reserve is in the southernmost part of the City of Gothenburg. The proximity to the city makes it a popular recreational destination, with about 73000 visitors each year. In 2018, the area was protected as a nature reserve to preserve its recreational, natural and historical values. The status as a nature reserve prohibits any exploitation and other harmful activities in the area. The area of the reserve is 1103 ha, of which 259 ha is land area and the rest is water [Ref. 1-3]. The management of the reserve includes promoting recreational and educational activities by creating new entrances, paths and signs, as well as holding guided tours. The management also includes restoring and improving terrestrial ecosystems such as grasslands through mowing and grazing and deciduous forests through selective clearing. A wetland has been restored to promote biodiversity further [Ref. 2, 4]. The reserve was created and is managed by the City of Gothenburg, the process of creating it involved consultation of stakeholders such as land owners, government agencies and NGO's [Ref. 1]. Some local landowners disagreed with the borders of the nature reserve having an impact on their land, leading to an appeal that was ultimately denied [Ref. 5, 6]

The urban farm of Lak'a Uta is an initiative launched by the NGO Fundación Alternativas, which established the first community garden in Bolivia, located in the city of La Paz at an altitude of 3,600 meters above sea level (1-3). The initial plan was to develop the garden on private land, but since the goal was to create an open space accessible to all citizens, the project eventually sought a public location (3). The subdistrict of Cotahuma granted them permission to use the Lak'a Uta park, an abandoned area rendered unusable by two landslides in the previous year (3). Through voluntary efforts and an investment of 2,800 euros, the land was transformed over three years to accommodate 40 plots of 16m² each, with individual families cultivating a variety of vegetables (3).
Now celebrating its 10-year anniversary, the project adheres to many principles of organic agriculture in an urban setting (5). The area has become a biodiversity hotspot, featuring an artificial pond, 16 wild plant species, and 39 fauna species, including 34 bird species, two types of frogs that provide natural pest control, and three bee species (3-5). Compost is produced naturally using waste management practices and worms (4-5). In addition to edible vegetables, the garden produces medicinal plants, some of which help stabilize the soil and prevent further landslides (3-4). The infrastructure also includes a rainwater collection system (3-5).
Originally, the project aimed to improve access to food, particularly in response to the growing urban population (1-3). Over time, it has also fostered a strong sense of community, while promoting urban gardening through educational workshops and disseminating information nationwide (1-5). It is estimated that 20,000 people have been educated on urban agriculture, healthy eating, and reconnecting with nature (5). The project has also contributed to shaping a local government law supporting urban gardening within the municipality (3).