Super-resolution reconstruction of GOSAT CO 2 products using bicubic interpolation

Abstract

Satellites provide global long-time series of spatio-temporal continuous CO₂ observations. However, it is difficult to be applied to the study of small-scale carbon cycle because of its low spatial resolution. In this paper, the Greenhouse Gases Observing SATellite (GOSAT) XCO₂ data are super-resolution reconstructed using bicubic interpolation, which improved the spatial resolution from 2.5° to 0.5°. CO₂ measurements from ten selected TCCON sites are used to compare with the reconstructed GOSAT. Further, the high accuracy Orbiting Carbon Observatory-2 (OCO-2) data analysed by the combination of geographical grid statistics and kriging is used to evaluate the reconstructed data. The results show that compared with the original GOSAT data, the reconstructed GOSAT data not only improves the spatial resolution but also has little loss of the average accuracy. The mean error of original data has significant seasonal fluctuations with a peak from February to March and a trough from June to July.