Building Local Climate Action Plans With Satellite Data

As the climate crisis intensifies, the urgency to tackle its impacts becomes paramount. Climate change, largely caused by human activities, poses severe consequences that affect metropolitan areas that are first in line not only to contribute to the broader challenge but also to ensure the livability and resilience of urban environments in the face of escalating hazards like flooding and heatwaves.

To address the challenge, local authorities develop climate and resilience action plans that cover various areas like adaptation, energy efficiency, air quality, transportation, waste reduction, green spaces or water management, to name just a few areas. In preparing such plans, analyzing the technical parameters and costs associated with proposed solutions and policies is essential for policymakers to make informed decisions within their political constraints. This is where space-based data insights can provide valuable multivariate information.

Satellite data offers multiple solutions and remote sensing is at the core of opportunities unlocked. The decrease in cost of satellite imagery, its increasing spatial and temporal resolutions as well as the emergence of new sensors including optical multispectral and hyperspectral imagery has unlocked an enriched portfolio of use cases for municipalities. In addition, synthetic aperture radar (SAR) and soon LiDAR imageries now offer new prospects for topography mapping, ground subsidence monitoring, independently from weather conditions, perspectives that could save lives if leveraged preventively as could have been the case to prevent the Paris rue de Trévise incident in which a gas line ruptured following ground subsidence events.

In addition to imagery, global navigation satellite system (GNSS) data can also play a key role in helping monitor navigational patterns of urban traffic, providing insights on urban logistics and mobility patterns. Integrating all these sources of data into emerging digital twins, real-time virtual representations of physical systems based on data inputs, has the potential of facilitating policy decisions and impact modeling, making them valuable tools for climate and resilience strategies. Projects like the Siradel Urban Climate Resilience toolkit exemplify the development of digital twins to address climate change and foster greener urban spaces.

Out of the multifarious potentialities of satellite data, several use cases are emerging to tackle climate change in urban areas. From optimizing green spaces to assessing air quality, managing traffic to mitigating flood risks, these cutting-edge technologies offer a diverse range of applications that empower cities to make informed decisions and shape sustainable urban environments.

Urban green space management is probably one of the most emblematic use cases for satellite data, given the importance of vegetation in climate plans. Satellite data that monitors vegetation health can help understand which species are most likely to thrive in each urban environment. The ability to track changes in vegetation quantity and quality also empowers urban planners to create healthier, more vibrant living spaces for their residents.

The use of satellite data has been pivotal in assessing and addressing environmental quality concerns, looking at both urban heat island formation and monitoring air pollution. Satellites like the Copernicus Sentinel-5P have enabled mapping pollutants such as nitrogen dioxide and fine particles.

Cities like Los Angeles have taken it a step further with its pioneering "Predicting What We Breathe" project that utilizes advanced machine learning algorithms to forecast air pollution events. Cities like Salzburg in Austria have been analyzing mobility patterns and traffic volume, successfully rerouting electric trolleybuses and reducing traffic congestion and improving air quality. This also applies to parking space management, where it increasingly becomes possible to identify parking space occupancy through high-resolution imagery and advanced algorithms, helping urban planners make informed decisions regarding the conversion of parking areas into green spaces, promoting a more sustainable and livable urban landscape.

These are just a handful of all the potential use cases of satellite data to climate and resilience action plans. What is certain is the proliferation of satellite imagery and geospatial data marks a new era in urban planning and management. By harnessing the power of satellite data, cities can forge a sustainable path towards resilience, livability, and a brighter future for urban dwellers.

So why are local authorities lagging behind when it comes to adopting space-based data? It must first be acknowledged that there is no single profile of local authorities, and all have varying sizes, priorities and financial capacities in utilizing satellite data. This fragments the demand and prevents pooling resources to negotiate cost, making budget anticipation challenging and makes it harder for institutional and commercial players to identify user needs. In addition, relevant solutions for urban applications are lacking due to absence of good enough spectral, spatial, and temporal resolutions.

While new satellite technologies emerge, very high-resolution imagery is still costly and technical limitations remain. In addition to cost concerns, local authorities lack awareness and the necessary skill sets in their workforce to effectively use space-based data, a gap that contributes to underutilization.

What can be done to increase adoption of space derived data by local authorities in support of climate and resilience action plans development? At first, it is critical to bring the understanding of satellite-based insights closer to decision groups like Cities4Climate, where major municipalities are represented and debate policy solutions to climate change. The role of space agencies is also key in bridging the gap between climate science, commercial space solutions and developing concrete use cases that can be developed hand in hand with local authorities. This is typically the role endorsed by the Space for Climate Observatory under the leadership of CNES, the French space agency.

But building pilot programs won’t be sufficient and there is a need to scale-up to actionable and replicable applications, a challenge where financing and political will power are key success factors. To succeed in this endeavor, the downstream space industry will have to come up with clearer pricing solutions that are easier for budget-conscious elected officials to understand and predict. Developing new types of costing plans and financial pooling mechanisms will be essential to broaden adoption by local authorities.

Finally, concrete adoption will have to be channeled via the development of appropriate human capital and skills in local authorities’ administrations, supported by space data solutions and platforms that can be easily integrated to tools and solutions already in use by local authorities’ agents. VS

Mathieu Luinaud is a manager in strategy consulting within the PwC Space Practice and a senior lecturer in Economics at Sciences Po Paris.