Jökull - 01.12.1986, Blaðsíða 60

Fig. 1. Geographical divisions used
in the analyses presented here. Also
shown are the places of origin of the
later Icelandic annals, plus Grund
and Möðruvellir where Jón Jónsson
lived. — 1. mynd. Staðarnöfn í grein-
inni.
their limitation. Nevertheless, given that other means
of estimating climate variability in Iceland are not
available for the time period covered, they are invalu-
able. Furthermore, because eighteenth-century docu-
ments containing climate information are copious, the
disadvantages resulting from subjectivity on the part
of the observer, and also on the part of the researcher
in interpreting the data, are offset by the fact that, for
any one weather event, there are usually a number of
independent descriptions.
Major sources used include travellers’ accounts,
various government documents, early newspapers,
weather diaries and private and official correspon-
dence. By far the most important data sources, how-
ever, are the eighteenth-century annals (Annálar
1400—1800) and the unpublished reports sent annu-
ally to the Governor of Iceland (Bréf til Stiftamt-
manns: abbreviated below to B.S.) by the sýslumenn
or sheriffs in all the different districts of Iceland.
The main sources used for the different regions are
as follows: annals (in Annálar 1400—1800) from the
north include Mœlifellsannáll, Vallaannáll, Annáll
Páls Vídalíns, Höskuldsstaðaannáll, íslands Árbók
and Espihólsannáll. Sheriffs letters are from the
northern districts of Þingeyjarsýsla, Húnavatnssýsla
and Skagafjarðarsýsla. Another important source for
the north of Iceland is the weather diary which was
written by the Reverend Jón Jónsson between 1747
and 1794 (Bergþórsson, 1957; Kington and Kristjáns-
dóttir, 1978). Jón lived at various sites in Eyjafjord
district: from 1747 to 1758 at Möðruvellir in Hörgár-
dal and from 1759 to 1769 at Guðrúnarstaðir. From
there, Jón moved to Grund, and then to Núpufell in
1785, where he lived until his death. Sources from the
west of Iceland are: Fitjaannáll, the continuation of
Fitjaannáll, Hestsannáll, Hvammsannáll, Hítardals-
annáll, the continuation of Hítardalsannáll and
Grímsstaðaannáll. Letters from the west are from
Snæfellsnessýsla, Dalasýsla, and from the northwest
from ísafjarðarsýsla and Barðastrandarsýsla. There is
only one eighteenth-century annal written in the
south, Ölfusvatnsannáll, but there are two good series
of sheriffs’ letters, from Árnessýsla and Rangárvalla-
sýsla. Eastern sources are Þingmúlaannáll and letters
from Múlasýsla. A few letters from the southeast,
from Austur-Skaftafellssýsla, have also been included
in the analysis. For the years 1781 to 1784 the major
sources used are the letters from the sheriffs and from
the Governor of Iceland sent to the Danish exchequer
(Rentukammer) and Jón Jónsson’s weather diary.
Because of the quantity of data in these sources, the
annals are used very little for this time. The sites
where the annals were written, plus two of the sites
where Jón Jónsson lived, are shown in Figure 1.
METHOD
The first step in any climate reconstruction based
on documentary evidence is to ensure, by careful
evaluation of this evidence, that only reliable and
accurate material is included. This will most fre-
quently come from documents which have been
written close in time and space to the events de-
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