This is the 11527th most frequent German word.
steigen
"Steigen" means "to climb" or "to rise."
Here, "steigen" refers to the increase or rising of the temperatures.
Die Temperaturen steigen im Sommer.
The temperatures rise in summer.
In this sentence, "steigen" denotes the upward movement or ascent of the bird into the air.
Der Vogel steigt in die Luft.
The bird ascends into the air.
Here, "steigen" is part of the phrase "aus dem Bus steigen," meaning to step or get off the bus.