This box model is designed to study the marine carbon cycle. It is based on Toggweiler (2008) and incorporates additional features including carbon isotopes, carbonate deposition/dissolution, and an optional sea ice module from Gildor and Tziperman (2001). The main program is couple.f. Details of the model configuration and parameterization are provided in Ma et al. (2011). The model outputs, derived from five experiments in Liu et al. (under review), are stored in two files per experiment: printout1_x and printout2_x. The data format is detailed in printoutreadme.txt. References: Liu, F., Huang, E., Du, J., M, W., Liu, Z., Lourens, J. L., and Tian, J. (under review), Eccentricity rhythms in the Oligocene-Miocene carbon cycle regulated by weathering and carbonate burial. Ma, W., Tian, J., Li, Q., and Wang, P. (2011), Simulation of long eccentricity (400-kyr) cycle in ocean carbon reservoir during Miocene Climate Optimum: Weathering and nutrient response to orbital change, Geophys. Res. Lett., 38, L10701, doi:10.1029/2011GL047680. Toggweiler, J. R. (2008), Origin of the 100,000-year timescale in Antarctic temperatures and atmospheric CO2, Paleoceanography, 23, PA2211, doi:10.1029/2006PA001405. Gildor, H., and Tziperman, E. (2001), A sea ice climate switch mechanism for the 100-kyr glacial cycles, J. Geophys. Res., 106(C5), 9117–9133, doi:10.1029/1999JC000120.