In January, the region with the highest amount of absorbed solar radiation is the Southern Hemisphere.

Here's why:

* Earth's Tilt: The Earth is tilted on its axis, and this tilt causes different hemispheres to receive varying amounts of solar radiation throughout the year.

* Summer in the Southern Hemisphere: January falls during the Southern Hemisphere's summer. During summer, a hemisphere is tilted towards the sun, receiving more direct sunlight and thus, more solar radiation.

While specific locations within the Southern Hemisphere will vary in their exact amount of solar radiation, generally, the Southern Hemisphere receives the most in January.