CIR-related proton flux enhancements identified at STEREO-A from 21 to 24 August 2016. Shown from top to bottom are the hourly 1.8–10.0 MeV nucleon⁻¹ proton fluxes, a proton anisotropy plot composed of 1.8–3.6 MeV nucleon⁻¹ proton intensities from 16 different viewing directions of the LET instrument, suprathermal electron PADs, one-minute-averaged magnetic field B, solar wind bulk speed V_p, proton number density N_p, proton temperature T_p, total pressure P_t and east–west flow angle. The CIR is highlighted by two blue vertical lines (14:00 UT on 21 August and 10:30 UT on 24 August). The red vertical dashed line presents the passage of the SI (10:09 UT on 22 August) and the magenta vertical line shows the peak values of proton fluxes (03:00 UT on August 23).