Final answer:
The deflection of warm water near the equator westward is due to the Coriolis force, which is caused by Earth's rotation. The direction of this force varies between the Northern and Southern Hemispheres, influencing weather patterns and ocean currents such as during El Niño events.
Step-by-step explanation:
The warm water near the equator normally gets deflected westward primarily due to the Coriolis force. This force is a result of the Earth's rotation and causes moving objects, including large bodies of air and water, to follow curved paths rather than straight lines.
In the Northern Hemisphere, the deflection is generally to the right, whereas, in the Southern Hemisphere, it is to the left. This effect explains why the circulation around low and high-pressure systems, such as hurricanes and tropical cyclones, occurs in a counterclockwise direction in the Northern Hemisphere and a clockwise direction in the Southern Hemisphere.
Moreover, events like El Niño can alter typical weather patterns and affect global climate by changing the distribution of warm water. During El Niño, the warm water that is usually found in the western Pacific migrates eastward along the equator, leading to significant impacts on marine life and extreme weather conditions in various regions.