Left panel: inferred values of Σ₈ = σ₈(Ω_m/0.3)^0.65 from an E-mode CCOSEBIs analysis of four mock cosmic shear surveys that suffer from PSF leakage (blue squares), a repeating additive pattern (black stars), and random but correlated noise on chip (green triangles) and pointing (magenta diamond) scales. The curves show the theoretical values of the 5 E-mode CCOSEBIs when varying Σ₈, calculated using the KiDS-450 noise only covariance matrix and redshift distribution; E_σ8σ8 (dashed), E_ΩmΩm (dotted), E_σ8 (middle solid), E_Ωm (dot-dashed) and E_σ8Ωm (lower solid). The inferred cosmology for each mock systematic survey can be compared between the 5 different modes. The higher the recovered E-mode is relative to the fiducial “no-systematics case” (circles), the stronger the bias is on the inferred value of Σ₈ and the more discrepant the inferred cosmology is between the different CCOSEBIs modes. The bias in Σ₈ can be compared to the grey region which shows the one-sigma error for Σ₈ from the KiDS-450 cosmic shear analysis, centred on the fiducial case. Right panel:B-mode CCOSEBIs from the four mock cosmic shear surveys. The measured B-mode signal, which does not depend on Σ₈, can be compared to the shape noise on a KiDS-450-like survey (shown in grey).