Mapping inland water carbon content with Landsat 8 data

ABSTRACT

Landsat 8 is the first Earth observation satellite with sufficient radiometric and spatial resolution to allow global mapping of lake CDOM and DOC (coloured dissolved organic matter and dissolved organic carbon, respectively) content. Landsat 8 is a multispectral sensor however, the number of potentially usable band ratios, or more sophisticated indices, is limited. In order to test the suitability of the ratio most commonly used in lake carbon content mapping, the green–red band ratio, we carried out fieldwork in Estonian and Brazilian lakes. Several atmospheric correction methods were also tested in order to use image data where the image-to-image variability due to illumination conditions would be minimal. None of the four atmospheric correction methods tested, produced reflectance spectra that matched well with in situ measured reflectance. Nevertheless, the green–red band ratio calculated from the reflectance data was in correlation with measured CDOM values. In situ data show that there is a strong correlation between CDOM and DOC concentrations in Estonian and Brazilian lakes. Thus, mapping the global CDOM and DOC content from Landsat 8 is plausible but more data from different parts of the world are needed before decisions can be made about the accuracy of such global estimation.

Acknowledgements

Estonian fieldwork and data analysis funding were covered by Estonian Science Foundation Grants 8576 and 8654, KESTA program project VeeObs, Estonian Basic Science Research Grant SF0180009s11, and Swedish FORMAS project ‘The Color of water – interplay with climate, and effects on drinking water supply’. The Brazilian Electricity Regulatory Agency (Agência Nacional de Energia Elétrica – ANEEL grant no. 8000003629) and FAPESP (Fundação de Amparo à Pesquisa do Estado de São Paulo – grant no. 2011/23594–8) provided instrumentation and funding for fieldwork campaigns in Brazil.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by Estonian Science Foundation Grants [8576 and 8654], KESTA program project VeeObs, Estonian Basic Science Research Grant [SF0180009s11], and Swedish FORMAS project ‘The Color of water – interplay with climate, and effects on drinking water supply’, the Brazilian Electricity Regulatory Agency (Agência Nacional de Energia Elétrica – ANEEL grant no. [8000003629] and FAPESP (Fundação de Amparo à Pesquisa do Estado de São Paulo – grant no. [2011/23594–8].