  Low-lying loops have been discovered at the solar limb in transition region
temperatures by the Interface Region Imaging Spectrograph (IRIS). They do not
appear to reach coronal temperatures, and it has been suggested that they are
the long-predicted unresolved fine structures (UFS). These loops are dynamic
and believed to be visible during both heating and cooling phases. Making use
of coordinated observations between IRIS and the Swedish 1-m Solar Telescope,
we study how these loops impact the solar chromosphere. We show for the first
time that there is indeed a chromospheric signal of these loops, seen mostly in
the form of strong Doppler shifts and a conspicuous lack of chromospheric
heating. In addition, we find that several instances have a inverse Y-shaped
jet just above the loop, suggesting that magnetic reconnection is driving these
events. Our observations add several puzzling details to the current knowledge
of these newly discovered structures; this new information must be considered
in theoretical models.
