Large bodies of water affect the climate, too. Large bodies of water have a moderating effect on temperature. The is, if it is cold inland, the land near the large body of water will not be as cold as it is inland. If it is hot inland, the land near the water will not be as hot. Inland, however, there my be great differences between the coldest and warmest temperatures.
Ocean currents play an important part in determining the climate, too.
The Gulf Stream moves from the warm Caribbean area, along the eat coast of the United States, to about Cape Hatteras. Then most of it moves across the Atlantic to Europe, Northern Europe would have a colder climate than it has if this warm current did not reach its coasts. Make a barometer with two jars. Fill a tall, wide-mouthed jar about half full of water. Fill an olive jar about one fourth full of water.