journals.ametsoc.org/doi/pdf/10.1175/JCLI3933.1Icelandic Coastal Sea Surface Temperature Records Constructed: Putting
the Pulse on
Air–Sea–Climate Interactions in the Northern North Atlantic. Part I: Com
parison with
HadISST1 Open-Ocean Surface Temperatures and Preliminary Analysis of Lo
ng-Term
Patterns and Anomalies of SSTs around Iceland
E
DWARD
H
ANNA
Department of Geography, University of Sheffield, Sheffield, United Kin
gdom
T
RAUSTI
J
ÓNSSON
Icelandic Meteorological Office, Reykjavík, Iceland
J
ON
Ó
LAFSSON AND
H
EDINN
V
ALDIMARSSON
Marine Research Institute, Reykjavík, Iceland
(Manuscript received 21 October 2005, in final form 14 February 2006)
ABSTRACT
A new comprehensive record of long-term Icelandic sea surface temperatur
e measurements, which have
been updated and filled in with reference to air temperature records, is pr
esented. The new SST series
reveal important features of the variability of climate in Iceland and the
northern North Atlantic. This study
documents site histories and possible resulting inconsistencies and bia
ses, for example, changes in observing
sites and instruments.
A new 119-yr continuous time series for north Iceland SST is presented, whi
ch should prove particularly
useful for investigating air–sea ice interactions around northern Icela
nd. As this is the only part of the
country to be regularly engulfed by winter and/or spring sea ice, it is ther
efore highly sensitive to climatic
change. The coastal series correlate well overall with independent Hadle
y Centre Sea Ice and SST dataset
version 1 (HadISST1) series from the adjacent open ocean (mean
r
0.59), although correlations are
generally higher in summer than winter and for south and east Iceland compa
red with the west and north.
The seasonal temperature range is generally twice as large at the coastal s
ites because of differential effects
of radiation, melting, mixing, and advection of warmer or colder air or wat
er masses, as well as spatial
resolution differences and smoothing in HadISST1.
The long-term climatological averages and graphs for the 10 SST stations a
nd/or their composites reveal
decadal variations and trends that are generally similar to Icelandic air
temperature records: a cold late-
nineteenth-century, rapid warming around the 1920s, an overall warm peak
circa 1940, cooling until an “icy”
period circa 1970, followed by warming. Regional differences between sit
es include relatively greater
(lesser) long-term variations for the eastern and southern (western and n
orthern) Icelandic coasts, suggest-
ing greater variability and influence of ocean current advection in the so
utheast. Moreover, Vestmannaeyjar
SST data reveal that the late-nineteenth-century cold period in the ocean
was not confined to the cold
currents off north and east Iceland but also affected the south coast marke
dly. The Stykkishólmur, Iceland,
SST record is relatively noisy and shows very little decadal variation, wh
ich may largely be due to fjord ice
in cold winters suppressing low temperatures. It is anticipated that rese
archers may find these Ice