The Program

Earthwatch Urban Resiliency Program

Earthwatch Institute launched the Urban Resiliency Program in Los Angeles in 2014 to fill critical research needs about creating resilient urban environments and providing opportunities for the public to become involved in doing real science about their local environment in a fun way. Our most recent program is Operation Healthy Air, which started in the summer of 2017. This program will engage partners and participants to map and measure how differences in their environment – such as the amount of trees or pavement, affect local air quality and temperature.

Our program was created as a response to the needs identified by local organizations for better information about which trees to plant to create a resilient urban environment. By mobilizing members of the public in citizen science, the program seeks to generate data that informs the creation of green space and also build a community of informed ambassadors who are willing and informed about how best to build a resilient urban environment. Dr. Darrel Jenerette of UC Riverside leads the program’s scientific team.

This is an effort to help cities and urban regions anticipate and respond to the effects of climate change, and to help urban populations understand and reduce the burdens they place on their environment.

Earthwatch Urban Resiliency Program is where citizens and institutions actively contribute in science-informed activities to build communities that are cooler, healthier, and use less water by increasing urban tree cover.


In an increasingly urbanized world, green space is growing more important

Southern California is facing serious challenges from climate change including increasing heat and decreasing water availability. Heavily populated regions across the diverse climates found in Southern California will be particularly hard hit by these impacts with the number of extreme heat days projected to be greater than 30 each year.

Increasing use and access to green space within urban areas has been identified by private and public institutions as an important strategy to help communities build resilience and adapt to climate change. Because trees require water, we need to know how different trees grow and provide benefits under future climatic conditions and water limitations. We need to increase our scientific understanding of these issues and share our results with managers and policy makers.

Science-based decision-making

Together with Dr. Darrel Jenerette and Peter Ibsen of the University of California Riverside, a field research program has been designed to help increase our understanding of how trees are performing in the Los Angeles region, and how they are likely to fare under future climate scenarios. To support this research, program partners are then engaged in specific citizen science activities across greater Los Angeles to contribute the large quantities of data needed to improve our understanding of how urban trees perform.


The right tree in the right place with the right support

Our citizen science efforts currently assess the performance of 30 tree species across the climatic gradient represented in Southern California. By examining how different individual trees of the same species fare across the climatic gradient (e.g. cooler and more moist by the coast to hotter and drier conditions in the desert), we are able to understand the degree to which different species are likely to cope with the future climate scenarios. We can then use this information to inform which trees are likely to be appropriate for future climate patterns, yielding more benefits to the surrounding community.

The program has:

  • Involved more than 600 community participants from Los Angeles to Riverside
  • Trained nearly 50 team leaders
  • Collected data on more than 1400 trees
  • Actively engaged over 15 partnerships

The Impact

While urban forests make up only a small percentage of the total forested area of California, the proximity to trees and their ecological benefits is important for human health. Some of the known benefits of urban forests include:

  • CO2 storage and sequestration
  • Cooling of air temperatures through shading and tree transpiration
  • Improved quality of life through aesthetic value, noise reduction, and reduction in stress.
  • Improved human health through minimizing heat effects, and reducing exposure to UV rays
  • Avoided emissions through reduced energy use
  • Air pollution removal through dry deposition
  • Reduced flood risk, and reduced water pollution
  • Increased property value through curb appeal and neighborhood charm


Learn about the science involved in the program.


Meet the scientific experts behind this project.


See the impact of the data we’ve collected so far.
Search Earthwatch Urban Resiliency Program