Jökull - 01.07.2003, Blaðsíða 4

de Ruyter de Wildt et al.
5 2
Figure 1. Map of Vatnajökull based on the DEM used by the mass balance model. The horizontal resolution is
500 m and contour lines are shown for each 250 m interval in altitude. Indicated are the sixteen weather stations
operated during the 1996 experiment and the names of the lobes. The permanent weather stations of Horna-
fjörður, Fagurhólsmýri and Kirkjubæjarklaustur are indicated with HOR, FAG and KIR, respectively. – Kort af
Vatnajökli sem sýnir legu sex sjálfvirkra veðurstöðva á jökli og þriggja veðurathuganastöðva utan jökuls.
sea-level to 2000 m with 88% of the surface between
700 and 1700 m. It comprises several domes overly-
ing volcanic caldera’s, some large surging-type lobes
and many smaller outlet glaciers. Since the end of the
nineteenth century it has been the topic of much re-
search, but only in the latest decades have data been
gathered in a systematic way. Overviews of previous
research are given by Björnsson et al. (1998a) and
Williams et al. (1997). The experiment reported in
this paper was carried out in 1996 by research groups
from the universities of Iceland, Utrecht (The Nether-
lands), Innsbruck (Austria) and from the Vrije Univer-
siteit of Amsterdam (The Netherlands). Twelve Au-
tomatic Weather Stations were placed on the ice cap
and four close to it (Figure 1). All of these were op-
erated from May 22
until September 1 and mea-
sured, amongst other variables, 2 m temperature, 2
m humidity, 2 m windspeed, pressure and incoming
and outgoing shortwave and longwave radiation. Fur-
thermore, close to U2 radiosonde ascents were made
twice daily. These produced profiles of temperature,
humidity, windspeed and pressure up to an altitude of
2 JÖKULL No. 52, 2003