The writer of the journal that Lina, Doon and Poppy find never names herself, but she does refer to herself as "an old woman" (20.2), so we know that much. She used to farm, too, which is why she was asked to partake in the experimental community that will be known as Ember.
The little we do know of our writer tells us that she's a bit rebellious. For one thing, she insists on keeping this journal, even though everyone has been instructed to bring no book or photos, or anything that refers to the world they live in above ground.
For another, when she and her new partner receive two infants to raise, they name them Star and Forest. It's a subtle act of resistance. The kids will grow up not knowing what either a star or a forest is since they'll live underground in Ember. But preserving the words will act as a reminder that these other things exist, and that the citizens of Ember may one day see them again.