  Over the last years, large (sub-)millimetre surveys of protoplanetary disks
have well constrained the demographics of disks, such as their millimetre
luminosities, spectral indices, and disk radii. Additionally, several
high-resolution observations have revealed an abundance of substructures in the
disks dust continuum. The most prominent are ring like structures, likely due
to pressure bumps trapping dust particles. The origins and characteristics of
these bumps, nevertheless, need to be further investigated. The purpose of this
work is to study how dynamic pressure bumps affect observational properties of
protoplanetary disks. We further aim to differentiate between the planetary-
versus zonal flow-origin of pressure bumps. We perform one-dimensional gas and
dust evolution simulations, setting up models with varying pressure bump
features. We subsequently run radiative transfer calculations to obtain
synthetic images and the different quantities of observations. We find that the
outermost pressure bump determines the disks dust size across different
millimetre wavelengths. Our modelled dust traps need to form early (< 0.1 Myr),
fast (on viscous timescales), and must be long lived (> Myr) to obtain the
observed high millimetre luminosities and low spectral indices of disks. While
the planetary bump models can reproduce these observables irrespectively of the
opacity prescription, the highest opacities are needed for the zonal flow bump
model to be in line with observations. Our findings favour the planetary- over
the zonal flow-origin of pressure bumps and support the idea that planet
formation already occurs in early class 0-1 stages of circumstellar disks. The
determination of the disks effective size through its outermost pressure bump
also delivers a possible answer to why disks in recent low-resolution surveys
appear to have the same sizes across different millimetre wavelengths.
