The hydrological and energy cycles are examined using the Community Climate System Model version 3 (CCSM3) for two climates, the Last Glacial Maximum (LGM) and Present Day. The Last Glacial Maximum occurred 21 ka (21000 yrs before present) and was the cold extreme of the glacial period with maximum extent of ice in the Northern Hemisphere. During this period, external forcings (i.e. solar variations, greenhouse gases, sea level, etc.) were significantly different in comparison to present, and this had an effect on the Earth's climate system. The Present Day simulation discussed in this study uses forcing appropriate for conditions before industrialization (Pre-Industrial 1800 A.D.). This research focuses on the joint variability of the hydrological and energy cycles for the atmosphere and lower boundary at Last Glacial Maximum. Hydrological and energy changes related to climate feedbacks are also analyzed in this study.