While typical land use maps highlight cities and key infrastructure in various regions, they often overlook documenting human activities in our oceans. With their large swaths of unbroken blue color to denote the world’s water bodies, maps generally give the impression that oceans are places where human activity is much more limited.
While certainly more human activity takes place on land, the oceans are increasingly becoming a place for exploitation. Whether it is for food, natural resources, transport, and other activities, we simply do not have a clear or simple way of knowing how much is occurring in our oceans. Now, using the power of AI, we have a way to better understand this diverse set of activity affecting our oceans.
Mapping reveals the acceleration of human activity in the world’s oceans
A new publication in Nature reveals the places of accelerating human activity in our oceans, where ocean human activity has been increasing at an exponential rate to about $1.5 trillion in economic activity and will likely double by 2030. Using satellite imagery, GPS, and artificial intelligence, a new map can be created that documents the various types of activities that are increasingly occurring.
Using GPS and remote sensing to detect non-public ship activity
A lot of this activity is not publicly disclosed, making it more important we know what is going on in our oceans given our ecosystem sensitivity to human activity. Satellite data, including dual-polarization synthetic-aperture radar (SAR) and optical (red, green, blue and near-infrared (NIR)) imagery from Sentinel 2, can be used to detect individual vessels, which can then be matched to the automatic identification system (AIS) GPS data provided from vessels. Deep neural networks can refine, improve, and pinpoint classification and types of individual ocean vessels.
Study: 63,000 vessels are present in the oceans at any given time
Between 2017-2021, over 53 billion vessel GPS points were monitored, with on average 63,000 vessels present in our oceans at any one time. In total, this analysis included 67 million image tiles. Overall, 72–76% of industrial fishing vessels are not tracked with available GPS data, particularly in south Asia, Southeast Asia, and parts of Africa. Transport and vessels carrying various forms of energy (e.g., oil) are not evident in GPS databases at a rate between 21-30%.
During the 2020 pandemic, fishing activities decreased and have not yet returned to their pre-pandemic levels, marking a decline in overall human activity in this sector. In contrast, the use of vessels for transport and energy has not seen a reduction.
Offshore wind turbine development has rapidly expanded
Notably, one of the most rapidly expanding areas of human activity is the construction of offshore wind turbines, which now exceeds the presence of oil structures in our oceans.. Areas of particular concentration of infrastructure built offshore can be found in Northern Europe, East Asia, particularly around China, northern South America, Western Africa, and the Persian Gulf. These areas reflect either a high number of oil infrastructure built or wind turbines.
China has built a 900% increase in wind turbines between 2017-2021. In Europe, the UK and Germany lead development of wind turbines, with 49% and 28% increase in production respectively between 2017-2021. In relation to fishing, trawlers are the most common vessels captured in the data. Most fishing vessels are less than 50 m in length, follow continental shelf breaks and seabed canyons, and stay close to shore mostly because of the methods of fishing they use.
Using geospatial technologies to asses the impact of human activities in the oceans
The key result of this work is not only that we can now better map the range of activities using the various satellite, GPS, and AI-based methods, but we can also determine what the impact of these activities might be. For instance, one can take the data and determine potential carbon emissions from vessels or the impact fishing has on various areas where high concentrations of fish could be found. This also demonstrates we need to better monitor human activity in our oceans if we are to know what human impact is in our oceans.
Past attempts to map human impact on the oceans similarly showed increasing human activity affecting almost every region of the globe by 2008. The poles, at that time, were among the few areas not as severely impacted by human activity. With the newer approach, more accurate and detailed maps can now be produced, whereas previous efforts could at best map at a resolution of 1 km2.
As human activities in our oceans continue to grow, there is an ongoing need for regularly updated maps to monitor these changes. Some of that activity may benefit us, particularly in energy production such as wind turbines. However, unmonitored fishing or oil infrastructure could do enormous damage to ecosystems, including trawlers that fish at the bottom of ocean floors or oil vessels leaking oil. Understanding the impact of these activities requires the use of diverse datasets and techniques. Additionally, varied methods are essential to precisely track the effects of each activity on our oceans and the planet.
 A public article discussing how AI, satellite imagery, and GPS tracking data can be used to understand ocean activity can be found here: https://theconversation.com/we-used-ai-and-satellite-imagery-to-map-ocean-activities-that-take-place-out-of-sight-including-fishing-shipping-and-energy-development-219367.
 Research discussing the results and impact of our ocean activity based the satellite, GPS, and AI-based approach can be found here: Paolo, F., Kroodsma, D., Raynor, J. et al. Satellite mapping reveals extensive industrial activity at sea. Nature 625, 85–91 (2024). https://doi.org/10.1038/s41586-023-06825-8.
 For more on an earlier approach that mapped human activity across our oceans, see: Halpern, B.S., Walbridge, S., Selkoe, K.A., Kappel, C.V., Micheli, F., D’Agrosa, C., Bruno, J.F., Casey, K.S., Ebert, C., Fox, H.E., Fujita, R., Heinemann, D., Lenihan, H.S., Madin, E.M.P., Perry, M.T., Selig, E.R., Spalding, M., Steneck, R., Watson, R., 2008. A Global Map of Human Impact on Marine Ecosystems. Science 319, 948–952. https://doi.org/10.1126/science.1149345.