The aim is to develop and validate atmospheric correction algorithms for CASI and the new hyperspectral sensor over water and land. We will measure optical and environmental characteristics of water, land and atmosphere while the aircraft passes over the same scene at several heights to evaluate the height dependence of atmospheric correction. The marine site will be the case 2 waters from the Tamar plume in Plymouth Sound, while the terrestrial site will be Plymouth Hoe. Surface measurements will include: . surface reflectance factors, radiance and irradiance over land based calibration/validation site, and over the sea surface using a hyperspectral radiometer; .radiance and irradiance profiles using the PML profiling radiometer; .absorption and backscatter profiles using the PML ac9, VSF-3 and HydroScat-6; .particulate and dissolved absorption spectra using spectrophotometry at PML and/or UoP; pigment analysis using HPLC at PML; .suspended particulate material measurements including size distribution at PML and/or UoP; .local aerosol optical depth using Microtops sun photometers; .aerosol type (optical depth, size distribution, refractive index) using sun/sky photometers. This dataset will allow detailed modelling of both in-water and atmospheric optics in support of the development and validation of atmospheric correction algorithms .In addition, the project aims to solve one of the major problems associated with application of such algorithms to images collected of the coastal zone. This issue is of great importance in the UK, given the dynamic nature of the coastal zone and the need for accurate monitoring of it. Remote sensing provides an ideal tool for monitoring change in such areas, however, an important step in this process is the ability to compare images from different dates and sites in different scenes. These comparisons require the digital counts from different scenes to be calibrated to common reference values, thus highlighting the need to establish suitable algorithms for use in this environment.The project is unique in terms of the collaborative effort between various higher education and research institutions in the South-West region.