Introduction to Remote Sensing
Remote sensing is a tool that has been used to measure, understand, and predict environmental changes since the 1970s. Since then, the technology has become much more accessible, and allows us to address conservation issues at much broader scales and in areas much more remote than before. For example, one of its many applications is the development of climate models at a global scale that allow planning for climate change by identifying areas that may act as refugia to increasing temperatures. Remote sensing contributes to new approaches to conservation by providing an overview of areas, changes, and threats that impact both species and ecosystems.
Remote sensing and the application of different remote sensing coral reef mapping tools is the topic of the online course opens in a new windowRemote Sensing and Mapping for Coral Reef Conservation. This three-lesson course helps marine managers understand and use remote sensing and mapping technologies – like the new Allen Coral Atlas – to guide and improve the effectiveness of reef management.
How is Remote Sensing Applied to Conservation?
Remote sensing has been used to support research in many ﬁelds such as tracking deforestation and illegal mining, monitoring shoreline changes, charting wildlife habitats, and tracking global temperatures. However, it is essential to understand the key concepts and the different approaches of remote sensing in order to choose the appropriate remote sensing data for your conservation plans and management decisions.
Example 1: Monitoring thermal stress on coral reefs at a global scale
The United States National Oceanic and Atmospheric Administration (NOAA) has developed the Coral Reef Watch Program based on satellite observation of daily measurements of sea surface temperature (SST). 95% of coral reefs are directly monitored daily. From these data, NOAA provides several products to inform managers of the risks of bleaching, including SST Anomaly, Coral Bleaching HotSpots, Degree Heating Weeks, and Bleaching Alert Area.
Example 2: Mapping reef areas in 3D to estimate ﬁsh biomass and biodiversity
The Stanford Center for Ocean Solutions used a remote sensing tool to better predict areas of high ﬁsh biomass and biodiversity. The technology called light detection and ranging (LiDAR) uses light in the form of a pulsed laser to measure variable distances. This allowed them to create 3D models, bringing to life the complexity of the coral reef seaﬂoor. They combined these models with satellite imagery of the reef to identify areas of complex reef structure, and the populations of ﬁsh living within them.
Source: Wedding, L.M., et al. 2019. Remote Sensing of Three‐Dimensional Coral Reef Structure Enhances Predictive Modeling of Fish Assemblages. Remote Sensing in Ecology and Conservation 5: 150-159.