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We present a new methodology which can determine magnetic helicity transportby the passage of helical magnetic field lines from sub-photosphere and theshuffling motions of foot-points of preexisting coronal field lines separately.It is well known that only the velocity component which is perpendicular to themagnetic field ($\upsilon_{\perp B}$) has contribution to the helicityaccumulation. Here, we demonstrate that $\upsilon_{\perp B}$ can be deducedfrom horizontal motion and vector magnetograms, under a simple relation of$\upsilon_t = \mu_t + \frac{\upsilon_n}{B_n} B_t$ as suggested byD$\acute{e}$moulin & Berger (2003). Then after dividing $\upsilon_{\perp B}$into two components, as one is tangential and the other is normal to the solarsurface, we can determine both terms of helicity transport. Active region (AR)NOAA 10930 is analyzed as an example during its solar disk center passage byusing data obtained by the Spectro-Polarimeter and the Narrowband Filter Imagerof Solar Optical Telescope on board Hinode. We find that in our calculation,the helicity injection by flux emergence and shuffling motions have the samesign. During the period we studied, the main contribution of helicityaccumulation comes from the flux emergence effect, while the dynamic transientevolution comes from the shuffling motions effect. Our observational resultsfurther indicate that for this AR, the apparent rotational motion in thefollowing sunspot is the real shuffling motions on solar surface.

Magnetic helicity transported by flux emergence and shuffling motions in Solar Active Region NOAA 10930