Nature-based solutions for climate change
Climate change is causing extreme weather events such as, floods, droughts and landslides, also known as hydro-meteorological hazards (HMHs). These disasters have increased globally in the last 30 years, with more than 18,000 taking place between 1980 and 2018, resulting in €4.8 trillion of damage. During the same period, Europe experienced nearly 3,000 disasters causing €631 billion of losses. Heatwaves and floods, in particular, have caused significant loss of life and economic damage.
Nature-based approaches can offer sustainable solutions to cope with climate change mitigation and adaptation challenges, but there has not been adequate demonstration or coordination of nature-based solutions (NBS) at the European level and hence these approaches are not reaching their full potential.
In the EU Horizon 2020 project OPERANDUM (Open-Air Laboratories for Nature Based Solutions to Manage Environmental Risks), the Global Centre for Clean Air Research (GCARE) worked with collaborators across Europe to manage the rising impact of severe weather and climate-related hazards using NBS. The team analysed over 300 case studies of floods, droughts, earthquakes and storms, and categorised natural hazards into four groups – geophysical, meteorological, hydrological and climatological – to understand their causes and associated risks.
The team’s research paper, published in Environmental Research, found that some hazards can trigger others simultaneously or in a cascading manner over time, causing multi-hazards and huge damage to humans, the economy and infrastructure. Floods were identified as the most frequent type of hazard in Europe, while droughts were the most complicated in terms of triggering risks of other disasters. Earthquakes and storms were the most destructive globally in terms of damage such as deaths and economic losses.
Scientists can play a significant role in increasing the adoption of these natural solutions by helping decision makers and politicians to understand their effectiveness and their cost over time.
An important part of the work has been to identify the most effective nature-based solutions for combatting different types of hazard: ‘green’ approaches such as urban parks, trees and grasses; ‘blue’ constructions such as small ponds; and ‘hybrid’ solutions which combine the two. Research shows that the most effective solution is not always being applied – for example, in cases of flooding, hybrid solutions such as green roofs and rain gardens are most often used, while the most effective flood management solutions are in fact blue constructions such as small ponds for river floods.
In a research paper published in Science of the Total Environment, GCARE critically evaluated different ways to monitor, assess and manage HMHs. A comprehensive study by GCARE to determine the design and optimization process of NBS to combat destruction caused by HMHs has also been published in the same journal. This study brought together 31 experts from across Europe from science, policy and practice and promoted the use of Open-Air Laboratories as a way for public and private organisations to join with the wider public to co-create, monitor and evaluate NBS.
Professor Prashant Kumar said: “We firmly believe that if we are to successfully combat climate change, then NBS have to be the first line of defense. Scientists can play a significant role in increasing the adoption of these natural solutions by helping decision makers and politicians to understand their effectiveness and their cost over time.”