What is the enviromental description of Lady Macbeth in Shakespeare's Macbeth?
The term "environmental," in terms of a character, is unusual. So I look to Lady Macbeth (in Shakespeare's Macbeth) with regard to "environmental psychology," which includes...
...all that is natural on the planet as well as social settings, built environments, learning environments and informational environments.
In Lady Macbeth's case, "social settings" and "built environments" to apply to her the most—including that she is a member of the nobility—married to a thane (like an English earl), living in a fine castle, in a beautiful part of the country—far enough away from general society that Macbeth is able to get away, literally, with murder.
Problems do at times arise with regard to "human-environment interactions," and in solving these difficulties, one looks to the model of human nature.
Perhaps what speaks most directly to Lady Macbeth, then, are the conditions that allow her to defy behavior expected of the nobility—for she is neither decent nor humane. This "model" that is referred to can accomplish a great deal, as well as predict expected outcomes. It can...
...manage, protect and/or restore environments that enhance reasonable behavior, predict what the likely outcome will be when these conditions are not met, and diagnose problem situations...
While "environmental stress and coping" seems to directly apply to Macbeth, Lady Macbeth seems to be centered more on "attention" and "preferred environment." Lady Macbeth notices her environment—she does not see its limitations, as much as its possibilities. When she learns that Macbeth has had predictions from the witches (one that has already come true), she hopes that Macbeth will return quickly for she is aware that she will be better able to control him once he returns home—and this ties into her "preferred environment."
Lady Macbeth notes (upon receiving Macbeth's letter) that she can't wait for her husband to come home so she can make him mean enough to kill the King—for she thinks Macbeth is too nice to commit murder:
Yet do I fear thy nature;
It is too full o’ the milk of human kindness
To catch the nearest way. Thou wouldst be great;
Art not without ambition, but without
The illness should attend it. (I.v.14-18)
It is also important that Duncan be under their roof. For there he is on enemy soil (without knowing it) and she feels she has the advantage—for this is her territory where she feels safe and knows how to make arrangements to achieve her end:
The raven himself is hoarse
That croaks the fatal entrance of Duncan
Under my battlements. (39-41)
In scene six, it is easy to see that the Macbeths have "home-field advantage." Duncan feels safe in their castle—so Lady Macbeth will be safe to carry out her plans:
This castle hath a pleasant seat; the air
Nimbly and sweetly recommends itself
Unto our gentle senses. (I.vi.1-3)
Once Duncan is inside, Lady Macbeth uses the environment to carry out her plan: she plays the respectful hostess; she arranges for parties and drinking; she drugs the guards' wine; and, she sets the stage for the murder. Even when it is done, Macbeth is worried, but she is unmoved:
Infirm of purpose!
Give me the daggers… (II.ii.67-68)
…If he do bleed,
I'll gild the faces of the grooms withal,
For it must seem their guilt. (70-72)
Lady Macbeth's relationship with her environment helps her to achieve her evil plans. Her home sets her at ease and allows her to do what is needed to be Queen.