Actually, the word infosphere already is a word, at least according to the Wikipedia, but here I wish to clarify what I will mean when I use the term, unless otherwise specified.
In my opinion, we need a single word that means, roughly, informational environment (context, situation, habitat, milieu, etc.) and I think infosphere is an excellent candidate for that job. To elaborate:
One’s infosphere is simply the sum of all of the information to which one has access in any given period of time.
This includes, of course, but is not limited to textual information, or even information conveyed by pictures, per se, or even that conveyed by speech. As I will be using this term, one’s infosphere is really all of the information to which one has access in some given period of time — literally any and every sort of data that can be detected by the senses and evaluated by one’s brain, and this includes even that brain’s own memories.
“The term has also been used by Luciano Floridi, on the basis of biosphere, to denote the whole informational environment constituted by all informational entities (thus including informational agents as well), their properties, interactions, processes and mutual relations. It is an environment comparable to, but different from cyberspace (which is only one of its sub-regions, as it were), since it also includes off-line and analogue spaces of information.”
And really the only reason I don’t feel comfortable about endorsing that particular wording is because the Wikipedia then goes on to explain that,
“According to Floridi, it is possible to equate the Infosphere to the totality of Being. This equation leads him to an informational ontology.”
And I am not at all clear on what that’s supposed to mean, and until I have a chance to read Floridi’s explanation I think it best to assume for now that the two definitions are somehow (and quite inscrutably) distinct, and especially to emphasize that I will be using my own definition of the word, at least until I have come to understand Floridi’s well enough to be sure they are the same.
 The Wikipedia cites this as a reference: Luciano Floridi (1999), Philosophy and Computing: An introduction