Final answer:
London, United Kingdom, experiences the greatest solar intensity in late June due to the summer solstice, when the Northern Hemisphere receives the most direct sunlight.
Step-by-step explanation:
The region that experiences its greatest solar intensity in late June is London, United Kingdom. This occurs during the summer solstice when the Sun shines most directly upon the Northern Hemisphere.
The Sun is at the zenith for observers on the Tropic of Cancer, which is at approximately 23° north of the equator. Given that London is in the Northern Hemisphere, it experiences long daylight hours and high solar intensity during this time.
In contrast, Johannesburg in South Africa, Melbourne and Wellington in New Zealand, and Rio de Janeiro in Brazil are all in the Southern Hemisphere. During late June, which is their winter season, these locations receive less solar intensity as the Sun is lower in the sky with shorter daylight hours.