You will notice that in this week's Schedule of Masses there are days named Ember Days.
According to the Priestly Fraternity of St. Peter:
"Ember Days are three days (Wednesday, Friday and Saturday) set apart in each of the four seasons for fasting, abstinence and prayer. Tied to the seasonal cycles of farming and harvesting, the purpose of Ember Days is to render thanks to God for the gifts of Creation and to ask His help in using them well. Since 1966, the fasting and abstinence are no longer prescribed but still encouraged."
For an Ordinariate perspective we can find lots more detail from Fr. James Bradley at his blog Thine Own Service, exploring especially the connection between Ember Days and the the ordination ceremony:
"To begin we must look at the specific purpose of the Ember Days in the season of Lent. Dom Prosper Guéranger notes that, in common with those in December, these Ember Days are oriented toward the bestowal of holy orders that traditionally took place on Ember Saturday, just before the Second Sunday of Lent. He comments that they are also 'to offer to God the season of spring, and, by fasting and prayer, to draw down His blessing upon it.' The context of the Ember Days within the season of Lent is in fact a later development."
There's much more to explore in Fr. Bradley's series on Ember Days, as they apply to the four seasons so consider it a Lenten sacrifice to read up on the subject.