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Strength of the polar field during the minimum of sunspot activity could serve as a good predictor of the amplitude of the next solar cycle. However, the polar fields are difficult to measure: the magnetic fields near the poles are relatively weak and nearly radial, and thus, the line-of-sight component is small and noisy. Each pole is not observable from Earth orbit for about a half a year. The evolution of the photospheric magnetic field is simulated reasonably well by the surface flux transport (SFT) models, which can be used to reconstruct the polar fields. However, active regions that emerge and decay on the far-side are not included in the simulations. How large is the impact of such regions on the strength of polar field? Using the near-side observations, we identified the statistical properties of small, short lived active regions, and we used these parameters to simulate the flux emergence on far-side of the Sun and their evolution using the SFT model. We find that adding active regions with short lifetimes to the far-side of the Sun results in (1) significantly stronger polar fields during the period of sunspot minima and (2) slightly delayed polarity reversals. The small, short lived active regions, which emerge and decay on far-side of the Sun, do not significantly affect the poleward flux surges, which are mostly caused by larger long-living active regions. Instead, the far-side emergence leads to a weak continuous flow of magnetic flux, which affects polar fields over long periods of time.

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