Climate change is one of the most significant environmental problems in the world, which refers to long-term shifts in temperatures and weather patterns.

Some human activities such as burning fossil fuels have caused the production of greenhouse gases and global warming. Researchers predict that the rising temperature and changes in weather patterns will increase more in the future. 
According to United Nations reports, the consequences of global warming are intense droughts, water scarcity, severe fires, rising sea levels, flooding, melting polar ice, catastrophic storms, declining biodiversity., etc. 
In addition to environmental risks, climate change threatens public health, resulting in forced migrations as well as social and political problems. However, climate change adaptation strategies could reduce the negative impacts and provide new opportunities for taking advantage of them.

In an exclusive interview with the Tehran Times, Maryam Rezaei Ghaleh, a researcher and expert in the urban landscape, climate change, and environmental health, said that nature-based solutions in urban areas are recognized as a critical strategy against the threats of climate change.
Q: What is climate change adaptation in cities?
A:  Today, half of the world's population lives in cities, and it is predicted that this proportion will increase to 70% by 2050. Cities are more vulnerable to climate change, and these changes might intensify the harmful effects of rapid urbanization and population growth, especially in developing countries. 
So, it is necessary to think of a solution to tackle climate change impacts as soon as possible. International organizations have committed many countries to reducing greenhouse gas emissions. Along with these mitigation strategies, adaptation strategies are also considered to minimize the adverse effects of climate change, improve urban sustainability, and take advantage of potential opportunities. 
Adaptation is a solution for decreasing climate change impacts that are necessary as a complement to mitigation strategies. This approach is not a new topic, and in the past, many societies have developed their cities to mitigate the extremely variable climate conditions effectively. With regard to current situations, we need adaptation strategies more than ever.
Q: What are urban nature-based solutions?
A: Among adaptation strategies, nature-based solutions have the potential to face the challenges of climate change and urbanization. These solutions play a fundamental role in achieving an integrated, livable, and sustainable city in the future. 
Nature-based solutions use the city's natural ecosystems, including urban green and blue Infrastructure. They have many benefits while being affordable and accessible. Green Infrastructure includes any public green space in the city, such as urban forests, urban farms and urban gardens, parks, trees in streets, green roofs, and green walls in buildings.
Besides, blue Infrastructure includes waterways, wetlands, permanent and seasonal rivers, and fountains. As a result, blue and green Infrastructure, the interconnected network of natural and semi-natural areas, is vital for making city and landscape resilient to mitigate climate threats such as reducing the temperature and flood risk.
Q: How can nature-based solutions and green Infrastructure contribute to climate change adaptation?
A: Climate change, along with the growth of urbanization, has increased the temperature in urban areas. So, the goal of the Paris Agreement is to limit governments from raising the global temperature to less than 2 degrees Celsius. Some research works have shown urban green Infrastructure could reduce temperature. Especially, trees and their shade could decrease urban heat more than other vegetation.
Green and blue Infrastructure can provide an opportunity to use floods and adapt to future climate changes. This Infrastructure can manage flash floods, collect flood water, and distribute it simultaneously. Therefore, this system can not only reduce the adverse effects of seasonal floods but also adapt to climate change through drought conditions.
Q: What challenges does the implementation of nature-based solutions face in Iranian cities?
A: Like other cities worldwide, Iranian cities have been affected by climate change impacts. The main consequences of climate change in Iran are extreme heat, lack of rainfall, and floods. Our country has been in a hot and dry climate, and these conditions are expected to become more severe. 
Therefore, the benefits of nature-based solutions for temperature reduction and flood management are valuable for Iranian cities. In the past, there have been many gardens in and around the Iranian cities. Also, the courtyards of houses as small gardens have been distributed in all parts of cities. 
But today, with population growth and more construction in cities, most of these gardens and yards have disappeared. Therefore, preserving the remaining urban gardens and using their benefits with correct and integrated urban management and planning is necessary. It is worth mentioning that replacing these trees requires a lot of time, and due to the lack of water, it cannot be easily compensated.