How might Sameness do away with sunshine in The Giver?

The concept of Sameness only has a few references in the book that describe how it works. When Jonas receives his first memory of sliding down a snowy hill on a sled, he asks the Giver afterwards why there is no more snow. The answer is that when the community decided to live under Sameness, they had to give up certain things in exchange for others. For example, they gave up snow in order to elongate agricultural periods. With Sameness, whatever a community wants to do away with is given away to the Receiver of Memory to hold onto. As a result, the people do not remember it, nor do they perceive it.

The second memory that Jonas receives is of sunshine.

"He could feel it through his clothed parts, too: a pleasant, all-over sensation; and when he licked his lips this time, the air was hot and heavy. . . He was simply alone someplace, out of doors, lying down, and the warmth came from far above. It was not as exciting as the ride through the snowy air; but it was pleasurable and comforting" (84-85).

Jonas perceives the word sunshine without any help from the Giver, as well as the word sky. This would suggest that Jonas has no knowledge of what the sun or the sky is; but, it doesn't say what he does know instead. For instance, do they live in a bubble or under some type of dome? If there are agricultural periods, and there is no sun, how do they grow their food? These questions are never answered within the text. All we know is that Jonas does not perceive the sun because he cannot feel it or see it; nor can he store memories of it. 

What is known is that everything that was given up is stored by memory inside the Receiver of Memory. In order to save the people from feeling any unnecessary discomfort or pain, all memories are transferred to him. Hence, memories of sunshine exist only in the Receiver. It is possible that once all memories of sunshine are stored with the Receiver, people simply do not notice it anymore. If there is no memory of sunshine, then the sun might also not have any effect on them. Or, if there is no memory of sunshine, does it therefore cease existing? 

What the community is left with, really, is a two-dimensional, black and white world. Without sun, there is no reflection of light; with no reflection of light, there is no perception of color; and without color, nothing can be differentiated from one to another. If there is no differentiation, there is no preferences and no available choices--only Sameness.