I don't believe you can get rid of this notification -- at least, not without a system-wide modification.
This warning is simply a way for you to see if/when a moderator or an administrator gives you a warning. It's an easy and immediately-visible way for you know when you've done something that went against the forum rules. Having a
0% warning means that you're a good, upstanding member of the forum and that you have no warnings whatsoever.
This warning is either a built-in feature in IP.Board forums, or it's an added feature (such as a plugin or a custom code modification). If I remember correctly, it's actually built-in. The point is, it'd be unreasonable for any single member to request an individual removal of his/her warnings, since it's either not possible to do it on a case-by-case basis or, if it
was possible, then it'd put unnecessary load on the administrator.
Um. I know it isn't my place to ask, but I'm rather curious... why would you want to remove such a helpful hint?

P.S.: Aside from the moderators and administrators, it seems that a member is the only one able to see his/her own warnings. For example, I can't see yours whether on your posts or on your profile.
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