The global carbon cycle: A test of our knowledge of earth as a system

P. Falkowski, R. J. Scholes, E. Boyle, J. Canadell, D. Canfield, J. Elser, N. Gruber, K. Hibbard, P. Hogberg, S. Linder, F. T. Mackenzie, B. Moore, T. Pedersen, Y. Rosental, S. Seitzinger, V. Smetacek, W. Steffen