There is no course textbook but some useful and relevant texts are listed below.

Durran, Dale R. *Numerical Methods for Wave Equations in Geophysical Fluid Dynamics (Texts in Applied Mathematics Series, Vol. 32).* New York, NY: Springer, 1998. ISBN: 9780387983769.

Haidvogel, Dale B. and Aike Beckmann. *Numerical Ocean Circulation Modeling.* River Edge, NJ: World Scientific Publishing Co., 1999. ISBN: 9781860941146.

Haltiner, George J., and Roger T. Williams. *Numerical Prediction and Dynamic Meteorology,* 2nd Ed. Hoboken, NJ: John Wiley & Sons, 1980. ISBN: 9780471059714.

Jacobson, Mark Z. *Fundamentals of Atmospheric Modeling.* Cambridge, MA: Cambridge University Press, 1998. ISBN: 9780521637176.

Kantha, Lakshmi H. *Numerical Models of Oceans and Oceanic Processes.* Academic Press; 1 edition, 2000. ISBN: 9780124340688.

Pedlosky, Joseph. *Ocean Circulation Theory.* New York, NY: Springer; 1st ed. Corr. 2nd printing edition, 2004. ISBN: 9783540604891.

A handy quick-reference for some methods is Numerical Recipes on-line.