What is the author's perspective in the memoir, Upstream?

Oliver is the narrator of this book, writing in past and present tense. She uses the past tense when she shares her memories and anecdotes. And she uses present tense for literary analysis and some pieces of narrative. Even when the stories are of her childhood, it is Oliver’s adult self, her present self, who tells the stories. The reader is given her perspective now, as she reflects back on the events of her past. Oliver’s voice communicates her inspiration and appreciation in almost all scenes related to nature, as well as those about literature and creativity. Simultaneously, she is experienced and handles a wide variety of uncommon situations in a leisurely manner.