Coastal ecosystems, including saltmarsh, have several characteristics that make them challenging to monitor remotely, including a high variation in vegetation cover across fine spatial scales due to steep salinity and inundation gradients [28] and high dynamicity over short time scales due to tidal influences [29]. Together these characteristics necessitate very high spatial resolution and fine-temporal scale monitoring approaches; however, there is often a trade-off between the spatial and temporal domains with remote sensing technologies [30]. Existing multispectral sensors onboard earth observation satellites such as Landsat-8 and Sentinel-2 have systematic, relatively short revisit intervals (16 and 5 days, respectively); however, they are limited by a relatively coarse spatial resolution (30 m and 10 m, respectively) that reduces their capacity to detect the fine spatial vegetation patterns typical of saltmarsh communities in NSW. Airborne sensors and UAVs generally can achieve the much finer spatial resolution necessary to detect saltmarsh biomass changes (<3 m). The airborne ArborCam multispectral sensor captures seven adjustable narrow spectral bands across the visible to the near-infrared region with a spatial resolution as fine as 0.01 m, dependent on the altitude of the aircraft. In addition to the increased spatial resolution, crewed aircraft platforms are more scalable than many UAVs and enable the scheduling of acquisition and flight planning for optimal illumination and environmental conditions in saltmarsh environments (e.g., tide levels). However, fine-scale temporal observations of saltmarsh seasonal dynamics incur increased costs and human resource requirements associated with repeat airborne acquisitions [24; 27]. New-generation CubeSat technologies may create new opportunities for the monitoring of the seasonal dynamics of saltmarsh ecosystems and the associated aboveground carbon content. CubeSats are miniature, lightweight satellites built to standard dimensions that can be customized with purpose-built sensors at relatively low cost. PlanetScope, an earth observation CubeSat sensor developed by Planet Labs Inc. (San Francisco, CA, USA), captures four-band visible to near-infrared images at a 3 m spatial resolution, and the PlanetScope constellation of 180+ CubeSats aims to image the entire earth daily [31]. These attributes are particularly advantageous for monitoring spatiotemporally dynamic landscapes such as saltmarsh at relatively fine scales and may allow for issues related to coastal ecosystem mapping and monitoring to be addressed in ways that were not previously possible. The aim of this study was to evaluate the feasibility of ArborCam and the PlanetScope CubeSat constellation for the mapping and monitoring of the aboveground carbon content in saltmarsh landscapes at fine spatial and temporal scales. Our specific objectives were (1) to assess ArborCam for mapping fine-scale variations in the aboveground carbon potential of saltmarsh communities; and (2) to assess the PlanetScope constellation for analysing the intra-annual variation of the saltmarsh phenological response. Our study focused on a saltmarsh community located in Jervis Bay National Park, NSW, Australia. The outcomes of this research provide support for the use of ArborCam and PlanetScope to routinely map and monitor the aboveground carbon content in coastal saltmarsh ecosystems.