Final answer:
When it's winter in North America, it's summer in South America due to the Earth's tilt and the different amounts of sunlight each hemisphere receives.
Step-by-step explanation:
When it is winter in North America, it is summer in South America because these two regions are located in different hemispheres. North America is in the Northern Hemisphere, while South America is in the Southern Hemisphere. The Earth's axis is tilted, which causes different amounts of sunlight to reach each hemisphere at different times of the year.
During North America's winter, the Northern Hemisphere is tilted away from the Sun, resulting in less direct sunlight and cooler temperatures. At the same time, the Southern Hemisphere, where South America is located, is tilted toward the Sun, receiving more direct sunlight and experiencing warmer temperatures. This creates the opposite seasons in the two regions.
For example, when it's December in North America, it's June in South America. This is why the seasons are reversed between the two continents.
Learn more about Seasonal variations in North America and South America