Increase or improve urban vegetation cover to help reduce outdoor temperature

Senegal, like many other West African countries, is in an unprecedented position when it comes to the threats climate change poses. Climate scientists predict that the country will likely experience increased temperatures, decreased annual rainfalls, a rise in sea levels, and an increased frequency of heavy rainfall events. Automatically these events will change drastically the social and economic structures of the country and are reasons for concern for the people of Senegal and their government. For example, the city of Thiès is in an area where environmental degradation is very advanced. The tree cover is in a situation of extreme fragility due to tree ageing or abusive tree cutting. To address many of these concerns, the city of Thies is trying to become sustainable through the development of green spaces that are expected to restore the city's ecological dimension and contribute to the reduction of greenhouse gases and the improvement of the living environment. (1,2)

The Sustainable Residential Complex project was a measure taken by the city of Dubai, one of the largest city ecological footprints, with a goal to reduce it to the smallest ecological footprint by 2050. For the past two decades, the UAE government has made an effort to lower its own dependency on fossil fuels, shifting toward more environmentally-friendly sources to power its cities. The sustainable residential complex development project is one of the few initiatives taken by the city administration of Dubai under Vision 2021. Located just outside Dubai the area is the first operational net-zero energy residential complex in Dubai. [1, 2]

The City of Fort Collins is "taking steps to restore flows, fish passage, and ecological function" of Colorado's Cache la Poudre River (Ref. 6). The river was "heavily manipulated for irrigation and mining" throughout the early 20th century (Ref. 6), and today continues subject to the impacts of gravel mining, agriculture and urbanisation (Ref. 1). Regional climate change predictions further complicate our ability "to understand how the river’s hydrology and ecology may respond to warming climate scenarios" (Ref. 1).
The City of Fort Collins was, therefore "invested heavily in this urban river through extensive planning efforts, purchase of approximately 700 hectares of lands within the river’s floodplain, projects to address stormwater control and conveyance, water quality management, and acquisition of in-stream flow water rights", and in 2011, the City’s Natural Areas Department published the Cache la Poudre River Natural Areas Management Plan which outlined "opportunities and challenges in supporting the river’s ecological function and reducing risks to life and property during significant flood events", particularly through the implementation of nature-based solutions (Ref. 1). A suite of nature-based solutions has since been proposed and implemented by the City of Fort Collins, two of which are the Sterling Pond Ecological Restoration (also referred to as North Shields Ponds), and the McMurry Natural Area Ecological Restoration (Refs. 1 and 2).

Eco-district creation in Ulaanbaatar comes under the Ulaanbaatar Green Affordable Housing and Resilient Urban Renewal Project (AHURP). The planned development areas are hotspots of greenhouse emissions and air pollution, mainly due to the widespread use of coal for heating and cooking. The project will transform the highly climate-vulnerable and polluting "ger" areas (traditional Mongolian tents) into zones that are low-carbon emitting, climate-resilient and affordable. This will be done through low-cost urban infrastructure, public facilities, and social housing units. The project's five phases will deliver about 20 eco-districts or sub-projects, with each covering an average of 5 ha. The project is a large-scale demonstration initiative that will leverage private sector investment to deliver affordable and green housing stock, and redevelop "ger" areas into urban areas that are resilient to climate change, contribute to decreased air and soil pollution, and will provide a liveable urban environment to "ger" area residents. It will also establish policies, mechanisms, and standards for sustainable affordable housing and green urban redevelopment. [1, 2, 3]

Douala is the economic capital of Cameroon and one of its largest cities. The city is located on the banks of the Wouri River (hence a port city) and its climate is tropical. The marine and coastal biodiversity of Cameroon is rich and diverse, and it is highly endangered because of human activities including artisanal and industrial fishing and pollution generated from industries, accidental loss of crude oil in transit or during loading or unloading. In Douala, thousands of inhabitants have settled in and around the mangrove swamps, destroying the mangrove ecosystem and endangering biodiversity including snakes, birds, fish, trees and frogs. Biodiversity studies are rare, and even if they exist, they are done in part and do not give an overview of the real state of biodiversity in the city. The city of Douala is full of many ecosystems of various natures (micro-ecosystems), each of which has species adapted to the environment. Besides this, Douala confronts itself with seasonal flooding and high temperatures due to climate change. In response to some of these challenges, a local entity, the Association of academics and researchers for Biodiversity conservation, initiated in 2020 an action that focused on environmental education and biodiversity conservation. The initiative also provides a framework for reflection and exchange on biodiversity issues. (1,3,4)

In 2019, in the city of Ulan-Ude, the most comprehensive and large-scale action "Green City" was launched [2,3,4,5,12], with the goal of creating an efficient and sustainable greening system in Ulan-Ude [1,7]. Nowadays, according to the city's norms, there are two times fewer green spaces per resident than is customary [7]. According to this program, by 2024, the provision of the population with public green spaces should be 10 sq. m per person [1,8]. Within the framework of the project, effective technologies for greening are already being introduced, and all green spaces growing in the city are being monitored [3,5,6]. Planting of green spaces is carried out under the guidance of the Scientific and Technical Council for the Integrated Greening of the City, which includes Buryat scientists and specialists from the City Administration [2].

Ecuador is considered one of the most biodiverse countries in the world (one of the 17th most diverse), due to the high diversity of their natural species. The country has around 23.056 taxonomic species of animals and plants reported, which constitutes the 6,1% of all species reported worldwide. (6) Quito, the country's capital makes no exception and is considered a biodiversity hotspot. In recent years, urban expansion has had a detrimental effect on the environment and the city’s ecology. All of these actions exacerbate the stresses on the different ecosystems, contaminate water sources and networks, and put the city’s capacity to supply ecosystem services at risk. To respond to many of these challenges the municipality of Quito initiated in 2020 a nature-based solution program under the EU framework of Clever Cities. (1) The project intends to position nature-based solutions as a means to improving public health, social cohesion, citizen security and increasing economic opportunities in those areas. (3)

The Anderson Road Quarry, once a vacant 40-hectare site is getting transformed into a sustainable residential neighbourhood while ensuring climate resiliency and low environmental impact in Hong Kong. The site will supply housing for 25,000 people. In addition to this, the city is employing a wide array of adaptive and resilient approaches including saving around 3,000 metric tons of CO2 annually, helping the city live up to its 65% to 75% carbon reduction goal by 2030 set in Hong Kong Climate Action Plan. [1]

Located in the heart of Hung Phu, a new urban area within Can Tho, K-Villa+ has been designed to "mak[e] the most of open and harmonious space[s] with nature, using green design solutions to improve bioclimatic comfort for users, while respecting sustainable values ​​and being friendly to the living environment" (Ref. 5). The low construction density of the building project has been coupled with prioritisation and installation of green areas both on the building itself and in the surrounding ground; permeable coverings to increase water percolation, and landscaping with native and climate-adapted trees and plants (Refs. 1 & 5.) An ecological pond has further been included in the landscaping of the villa's grounds and a rainwater harvesting system has been installed (Ref. 3). Through the application of these green design solutions, the urban heat island is considered to be reduced and bioclimate improved for those within the building, and biodiversity promoted through the planting of a variety of native species (Refs. 1, 2, 3 & 5).

Note that due to a lack of data, the exact point location of the villa is not depicted in the map below, but rather the new urban district, Hung Phu, in which the villa sits.

Once empty paved area between the houses on Marat Street in St. Petersburg now has been turned into a cosy green garden [4, 5, 6]. The project was developed by a group of students and initiated by the Green Petersburg Foundation, Plants for Friends, "Vladimirsky" Municipal District and others [1, 3, 4, 5]. The square landscaping project contributes to the city's adaption to climate change, a need to increase urban green zones, reducing excessive heat and rainfall levels, and the creation of habitat for birds, among others [3]. The square acquired the concept of a harmonious combination of natural motives and the mood of the Russian landscape [4].