Measurement of the background levels and study of the chemistry of trace organic carbon species in the remote marine troposphere occurred during an April--July 1987 SAGA II cruise in remote regions of the Pacific and Indian Oceans. Measured compounds included carboxylic acids, formaldehyde, light hydrocarbons (C2--C4), and ozone. The results show seasonal, diel, and spatial dependencies for the organic acids. Distinct latitudinal gradients are seen for most sampled compounds. Formic acid is well correlated with suspected precursors, formaldehyde and light hydrocarbons. Acetic acid follows a similar pattern as formic acid, although its precursors are as yet undefined. Diel patterns of low amplitude for the organic acids in the remote marine troposphere suggest a natural contribution to tropospheric photochemistry, and to the global carbon cycle as well. For the northern hemisphere Pacific Ocean, the mean formic acid mixing ratio was 0.80¿0.30 ppbv, the mean acetic acid value was 0.78¿0.32 ppbv. For the southern hemisphere Pacific Ocean, formic acid averaged 0.22¿0.13 ppbv, for acetic acid, the mean was 0.28¿0.18 ppbv. For the northern hemisphere Indian Ocean, the mean formic acid mixing ratio was 0.75¿0.24 ppbv, and the mean acetic acid value was 0.69¿0.27 ppvb. For the southern hemisphere Indian Ocean, the mean formic acid value was 0.19¿0.17 ppbv, and the mean acetic acid value was 0.29¿0.16 ppbv. Highest levels of organic acids were encountered near known anthropogenic source regions, in air masses of continental origin, or near regions of naturally produced alkenes (C2, C3). The ozone-alkene oxidation scheme appears to play a major role in gas phase organic acid production in the remote marine troposphere. Nighttime gas phase deposition of the organic acids onto the ocean surface appears to be a major sink. ¿ American Geophysical Union 1990