The atmosphere and oceans are constantly moving. their activity is due primarily to
the sun's energy
the moon's gravity
the earth's gravity
air pressure

Sun's energy

solar radiation reaches the earth's surface and heats up the atmosphere and ocean as well. however, the heating is unequal. the air which has been heated up, expands and rises, whereas cold, dense air moves downwards, setting up currents and motion in the atmosphere. these wind currents are also responsible for causing ocean surface currents. along with this, unequal heating of ocean by sun's energy also leads to setting up of deep conventional currents within the ocean, thus setting it in constant motion.