Modeling and observational studies on the global and regional scale provide evidence that landuse change and landscape dynamics exert major influences on the climate system. In our talk we present our most recent work on the relative role of landuse change, the biogeochemical effect of increased carbon dioxide, and the radiative effect of increased carbon dioxide on regional and global climate. Our results provide evidence of the teleconnection of land-surface effects regionally and globally. Among our conclusions is that climate change assessments which do not include landuse change and landscape dynamics are ignoring first-order human effects on the climate system and are, therefore, unlikely to be realistic predictors of future climate.