Climate change and changes in land use/land cover due to human activities have contributed to significant alterations in ecosystem properties and functioning during the 20th century. These changes are likely expected to continue during the 21th century. However, the consequences of these dramatic changes in ecosystems in term of the surface energy budget and hydrological cycle remain unclear.

We present our results to quantify these effects using the offline NCAR CLM3 that is driven by the Princeton reanalysis data for the past 50 years. Some sensitivity experiments are made to examine the contributions of changes in land use/land cover and climate to changes in radiative budget, surface energy balance, and water balances. The temporal and spatial variations in regional and global surface energy budget and water balances are analyzed. We will also analyze the causes that may lead to these variations and trends taking into account the influence of climate change and changes in land use/land cover on the surface energy budget.