The last few years have seen increasing calls to protect and connect at least half the Earth for nature conservation. Scaling up our protected area system—currently at 15.1% of Earth’s land surface—to 50% is an ambitious target, but one that is increasingly recognized as essential to stop the extinction crisis and stabilize climate. Despite a myriad of global maps from conservation biologists highlighting sites of importance for rare species, threatened species, intact habitats, or sites of high diversity, to date there was not a comprehensive map of how the world might go about protecting half the terrestrial realm. This paper hence started with a global vision—and question—what would it take to ensure a prosperous world for future generations? More specifically, where do we need to secure vital habitats to stop the extinction crisis and stabilize climate?

 To answer these questions, we started with the existing network of protected areas – and then identified where terrestrial habitat remains outside these areas. Secondly, we sought to map key unprotected sites by bringing the various prioritization schemes into the tent to make sure that our ‘blueprint’ was inclusive of the well-established as well as newly available datasets. We brought in 11 published biodiversity layers, including everything from wilderness areas to important sites for rare plants.

Together, these areas comprise 30.6% of the terrestrial realm. Protecting this amount of land also stores 1.3 trillion tonnes of carbon, which is crucial for Earth’s climate stabilization. While this amount is substantial, it is not enough to meet global climate targets. To identify additional high priority areas for carbon storage, we used a new map of total carbon biomass to select remaining unprotected habitat in high carbon ecoregions. This helped us identify additional areas that could receive designation as ‘Climate Stabilization Areas'. Next, we overlaid areas in need of protection with maps of areas managed or claimed by Indigenous Peoples. Our results highlight the vital role of Indigenous lands, as they cover at least 35% of the Global Safety Net. 

This snapshot of the Global Safety Net shows protected areas (in dark green), areas critical for rare species (magenta), and proposed climate stabilization areas (blue), as well as a network of proposed corridors (yellow lines). To see a video of the Global Safety Net, explore our interactive map, or download data layers, please visit https://www.globalsafetynet.app.

 To bring all this data together, we used the freely available Google Earth Engine (GEE) computing platform. As COVID sent our research team out of University facilities and to our home computers, never before had cloud computing become so essential. What would have previously been months of computer hours—and impossible on home computers—could be run and re-run in hours to days on the GEE platform.

 A complementary global-scale connectivity analysis was performed by the Brazilian research organization Globaïa. Our goal here was to provide a first cut at connectivity needs based on wide-ranging mammals of each continent. This demonstrated that a relatively modest land area—approximately 350 million hectares—could connect isolated fragments of nature together, increasing the resilience of ecosystems and our biosphere as a whole. To our knowledge, this is the first attempt to assess how Earth’s remaining habitats might be connected.

Co-author Carly Vynne was inspired to help build a Global Safety Net that included all important habitat while working in the Brazilian Cerrado, where her work showed how even small fragments and corridors can be significant for conserving large mammals like jaguars. Brazilian colleague Manno França used continent-specific information to design a series of proposed corridors to connect intact lands and ensure a connected Global Safety Net. This photo is courtesy of Fundacíon Sumac Muyu, which is working to conserve and connect sites in Ecuador, and is a recent grantee of the Quick Response Fund for Nature, which will help local organizations secure land that contributes to the Global Safety Net.

 Our hope is that this blueprint can be superseded over time with local and regional conservation plans as they become available and updated. Until then, the Global Safety Net provides a ‘common but differentiated’ approach for how countries can contribute to a global nature target. We’ve made a web viewer available, so that regions and countries can see how they might contribute to a global conservation agenda.

The Global Safety net was built based on global datasets, but we hope that it will eventually be supplanted by regional conservation strategies that can roll up to show each region’s vision and commitment to global sustainability goals. Here, a transboundary working group in Cascadia builds a regional conservation vision. A dynamic support tool will ensure the Cascadia regional plan remains a living plan—and the authors hope to one day make the whole Safety Net live in Google Earth Engine so that targets can be adjusted as landscape change happens.  

Creating a Safety Net is important for preventing future pandemics, ensuring access to adequate ecosystem services, and to simply ensure nature isn’t something left in a few remote, far off places. Now more than ever, in a post-COVID world, all of humanity deserve access to nature and the myriad of benefits it provides to our mental, physical, and spiritual health. The Global Safety Net shows how every place and region can contribute.

 Our paper can be found here.

Here, co-author Carly Vynne checks a camera trap set up to survey for lynx in Washington State. As the Global Safety Net was published, much of the American West was blanketed in stifling wildfire smoke. Our ability to keep species such as lynx on landscapes into the future will require management to keep pace with disruptive changes such as fire. Future versions of the Global Safety Net could include climate projections.