A grassland productivity model, based on temperature-moisture interactions and informed by observations made across a range of North American grassland ecosystems, was used to predict the response to climate change based on CMIP-5 climate projections over the next century. I will present the results of the model analyses which indicate a future shift of grassland growth towards both earlier spring emergence and delayed senescence in autumn, which together compensate for drought-induced reductions in summer productivity in most North American grassland regions.