Living Planet   


GOCE: Is aliasing a cause for concern?

Philip Moore(1)and Sarah Crisp(1)

(1) School of Civil Engineering and Geosciences, Newcastle University, Newcastle, NE1 7RU, United Kingdom


Several authors have considered the effects of short-term temporal variability in the Earth’s gravity field on the inter-satellite range- rate measurements from GRACE and the associated aliasing of the monthly solutions leading to the possibility of spurious signals in the seasonal to annual signatures. Similarly, for GOCE aliasing may occur as the static gravity field solution will be time-averaged over two observation periods separated by a period of hibernation. In such a scenario it is conceivable that the time average of the annual gravity field signal will be non-zero. In consequence, this study discusses the possible aliasing of the static GOCE gravity field in the presence of temporal variability due to mass redistribution in the hydrosphere, atmosphere and oceans and attempts to quantify the magnitude of the aliasing in terms of the degree variances.


Keywords: ESA European Space Agency - Agence spatiale europeenne, observation de la terre, earth observation, satellite remote sensing, teledetection, geophysique, altimetrie, radar, chimique atmospherique, geophysics, altimetry, radar, atmospheric chemistry