Coastal monitoring is a topic of great interest both from a scientific point of view—given the complexity of the coastal phenomenology—and from an applicative point of view, considering the significance of the safety and protection of the coastal environment and infrastructures.

As an example, the capability to monitor both the causes and the effects of the coastal phenomena is very relevant in order to provide decision support to stakeholders engaged in the design and construction of coastal infrastructures and in the subsequent monitoring also with environmental protection aims.

In this context, the main pillar of the monitoring strategy is based on the use of sensors both in situ and remote, which provide the accurate measurement of physical and biochemical parameters over the water column as well as of hydrodynamic phenomena (such as waves, winds, and currents). These measurements together with the use of ad hoc models allow for a complete monitoring of coastal phenomena on small and large scales and also allow for a more accurate calibration of the models themselves.

The aim of this special issue is to provide an overview of the emerging sensing technologies for monitoring of the coastal areas from the coast, out the sea, and from the space.

Potential topics include, but are not limited to:

• Sensors (radars, cameras, buoys, probes, etc.) for observing wind and waves
• Sensors for monitoring of coastal phenomena on a small scale such as macro vortex, upwelling, coastal erosion, wave’s diffraction, and wave reflection
• Sensors to observe current and bathymetry
• Sensors for detection of oil spills and their propagation
• Combination of sensors and models for coastal observations, forecasting, and early warning systems