Since As You Like It is a comedy, the atmosphere, especially in the Forest of Arden, is portrayed as a light, happy atmosphere, despite the harshness of reality. Most importantly, As You Like It is a pastoral play, and like other pastoral literature, the forest is portrayed as a peaceful and even healing place. Pastoral literature likens the country to a type of utopia, while city life is portrayed as being full of corruption.
We see the jovial atmosphere in the forest especially portrayed by Duke Senior and his courtiers. Despite the obvious hardships they must face, they remain happy and optimistic, as shown in Duke Senior's first speech in Act 2, Scene 1. He even opens by asking his courtiers:
Hath not old custom made this life more sweet
Than that of painted pomp? Are not these woods
More free from peril than the envious court? (2-4)
What's more, they also seem to have plenty, also lending to the jovial atmosphere. We especially see how much they have when they are able to offer Orlando and Adam something to eat in Act 2, Scene 7.
Beyond how cheerful Duke Senior and his courtiers are in the face of adversity, other elements lend to the jovial, healing atmosphere in the forest. Touchstone, the fool, is able to make even melancholy Jaques laugh; Oliver is transformed into a loving brother when Orlando rescues him in the forest from a lioness; and even several marriages take place, showing us what ultimately a happy, healing place the forest is presented as being.