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Context: There is a lively debate about the solar oxygen abundance and therole of 3D models in its recent downward revision. The models have been testedusing high resolution solar atlases. Further testing can be done usingcentre-to-limb variations. Aims: Using high quality observations of oxygenlines across the solar surface we seek to test if the 3D and 1D modelsreproduce their observed centre-to-limb variation (CLV). In particular we seekto assess whether the 3D model is appropriate to derive the solar oxygenabundance. Methods: We use our recent observations of OI 777 nm, OI 615.81 nm,[OI] 630.03 nm and nine lines of other elements for five viewing angles0.2<mu<1 of the quiet solar disk. We compare them with the predicted lineprofiles from the 3D and 1D models computed using the most up-to-date lineformation codes, line data and allowing for departures of LTE. The CLV of theOI 777 nm lines is also used to obtain an empirical correction for the poorlyknown efficiency of the inelastic collisions with H. Results: The 3D modelgenerally reproduces the CLV observations of the lines very well, particularlythe oxygen lines. From the OI 777 nm lines we find that the classical Drawinrecipe slightly overestimates H collisions. The limb observations of the OI615.82 nm line allow us to identify a previously unknown contribution ofmolecules for this line, prevalent at the solar limb. A detailed treatment ofthe [OI] 630.03 nm line shows that the 3D modeling provides an excellentagreement with the observations. The derived oxygen abundances with the 3Dmodel are 8.68 (OI 777 nm), 8.66 ([OI] 630.03 nm) and 8.62 (OI 615.82 nm).Conclusions: These additional tests have reinforced the trustworthiness of the3D model and line formation for abundance analyses.

Oxygen lines in solar granulation. II. Centre-to-limb variation, NLTE line formation, blends and the solar oxygen abundance