The ocean's impact on weather and climate is significant. Water, particularly deep water, requires much more energy to change temperature than does the air, so it acts as a moderator, keeping weather from getting too hot or too cold in locations downwind from the ocean. Even landlocked parts of the world like ours are affected by faraway sea surface temperatures.
Our warming climate has been warming the oceans unevenly. Large-scale, oceanic "heat waves" have been shown to greatly impact weather patterns by helping to generate low pressure systems and by introducing huge volumes of evaporated water which can increase thunderstorm activity which, in turn, can cause diversions in the jet stream. Large-scale weather, such as heat waves, cold snaps, wet periods and droughts, can all change in frequency or intensity due to anomalously warm sea surface temperatures.