  Spectroscopic observations of the emission lines formed in the solar
transition region (TR) commonly show persistent downflows of the order of
10--15 km/s. The cause of such downflows, however, is still not fully clear and
has remained a matter of debate. We aim to understand the cause of such
downflows by studying the coronal and TR responses to the recently reported
chromospheric downflowing rapid red shifted excursions (RREs), and their impact
on heating the solar atmosphere. We have used two sets of coordinated data from
SST, IRIS, and SDO for analyzing the response of the downflowing RREs in the TR
and corona. To provide theoretical support, we use an already existing 2.5D MHD
simulation of spicules performed with the Bifrost code. We find ample
occurrences of downflowing RREs and show several examples of their
spatio-temporal evolution, sampling multiple wavelength channels ranging from
the cooler chromospheric to hotter coronal channels. These downflowing features
are thought to be likely associated with the returning components of the
previously heated spicular plasma. Furthermore, the TR Doppler shifts
associated with them are close to the average red shifts observed in this
region which further implies that these flows could (partly) be responsible for
the persistent downflows observed in the TR. We also propose two mechanisms (a
typical upflow followed by a downflow and downflows along a loop), from the
perspective of numerical simulation, that could explain the ubiquitous
occurrence of such downflows. A detailed comparison between the synthetic and
observed spectral characteristics, reveals a distinctive match, and further
suggests an impact on the heating of the solar atmosphere. We present evidence
that suggests that at least some of the downflowing RREs are the chromospheric
counterparts of the TR and lower coronal downflows.
