Abstract. Intertidal habitats are unique because they spend alternating
periods of submergence (at high tide) and emergence (at low tide) every day.
Thus, intertidal temperature is mainly driven by sea surface temperature
(SST) during high tides and by air temperature during low tides. Because of
that, the switch from high to low tides and vice versa can determine rapid
changes in intertidal thermal conditions. On cold-temperate shores, which
are characterized by cold winters and warm summers, intertidal thermal
conditions can also change considerably with seasons. Despite this
uniqueness, knowledge on intertidal temperature dynamics is more limited
than for open seas. This is especially true for wave-exposed intertidal
habitats, which, in addition to the unique properties described above, are
also characterized by wave splash being able to moderate intertidal thermal
extremes during low tides. To address this knowledge gap, we measured
temperature every half hour during a period of 5.5 years (2014–2019) at nine
wave-exposed rocky intertidal locations spanning 415 km of the Atlantic
coast of Nova Scotia, Canada. This data set is freely available from the
figshare online repository (Scrosati and Ellrich, 2020a;
https://doi.org/10.6084/m9.figshare.12462065.v1). We summarize the main
properties of this data set by focusing on location-wise values of daily
maximum and minimum temperature and daily SST, which we make freely
available as a separate data set in figshare (Scrosati et al., 2020;
https://doi.org/10.6084/m9.figshare.12453374.v1). Overall, this
cold-temperate coast exhibited a wide annual SST range, from a lowest
overall value of −1.8 ∘C in winter to a highest overall value of
22.8 ∘C in summer. In addition, the latitudinal SST trend along
this coast experienced a reversal from winter (when SST increased
southwards) to summer (when SST decreased southwards), seemingly driven by
alongshore differences in summer coastal upwelling. Daily temperature maxima
and minima were more extreme, as expected from their occurrence during low
tides, ranging from a lowest overall value of −16.3 ∘C in winter
to a highest overall value of 41.2 ∘C in summer. Daily maximum
temperature in summer varied little along the coast, while daily minimum
temperature in winter increased southwards. This data set is the first of
its kind for the Atlantic Canadian coast and exemplifies in detail how
intertidal temperature varies in wave-exposed environments on a
cold-temperate coast.