Electronic Supplementary Material
Figure S1. Fading evidence of old land use (reindeer corral) on the eastern slope of Mt Njulla
(see Figure 1 and Supplementary Table 1). Top-left, air photo 1959, top-right, air photo 2000
(Swedish Land Survey, Lantmäteriet), bottom, indications on the ground 2006 (Photo R. Van
Bogaert).
1
Table S1: Data sources for Callaghan et al “Ecosystem change and stability over multiple decades in the Swedish sub-Arctic: complex
processes and multiple drivers”
(The numbers in the column on Data Sources refer to the reference numbers in the manuscripts` reference list.)
Figure
Component
Fig. 2: Abiotic
change
Data Sources
Methodology
Calculations
68.36, 18.81 at Abisko
Scientific Research Station
(ANS).
Backdrop maps are
standard products used by
courtesy of the National
Swedish Cadastral
Authority (Lantmäteriet,
Gävle)
Maps produced in ESRI
ArcMap (Arc-Info) and
exported to Adobe
Illustrator for final
production.
Background map
Entire region
Swedish regional survey
map, Lantmäteriet, Gävle
Components digitised onto
the backdrop map
None
Historic land use
Entire region
[58] (figs. 6, 8, and 9).
In situ inventory and
literature study
None
Reindeer corral
68.34, 18.67
Van. Bogaert, R., pers. obs.
Photographic evidence
None
Background map: summer
degree-day change 1913 2009
Entire region; 68.36, 18.81
(ANS); 68.42, 18.17
(Katterjåkk)
[27], [28]
Climate downscaling from
observation at ANS
(monitoring programme),
Katterjåkk (SMHI regular
survey), and manually
deployed thermo-loggers
(across the region).
All figures:
Fig. 1: Land use
and infrastructure
Location
(decimal WGS84)
2
ArcGIS Maplex Label
Engine was used to
optimise the location of
objects, where the strategy
was chosen to maximise
the number of exact
positions while retaining
the overall neighbourhood
topology.
Arithmetic means for
reference periods 19131930, 1931-1960, 19611990, and 1991-2009.
Change is calculated as
difference between
averages across the first
and last periods. Primary
temperatures transformed
Mean annual temperatures
and temperature change
68.36, 18.81
[173]
ANS monitoring
programme
Snow-depth change 1913 2012
68.36, 18.81 at eastern
ANS transect
[19], [173]
ANS monitoring
programme
Permafrost temperature
change 1980 – 2002
68.35, 18.85 (Kursflaket)
and 68.35, 18.90
(Storflaket)
68.35, 18.85 (Kursflaket)
[51] Tables 2 and 3
Borehole temperature
monitoring at Kursflaket
and Storflaket
Borehole temperature
monitoring at Kursflaket.
Mechanical probing
Permafrost thickness
change 1980 – 2009
Permafrost thickness
change 1992 – 2009
Active layer change 1978 –
2011
Lake-ice change 1913 –
2006
UV solar radiation change
together with figure 5.
[51] P. 564, section
“Permafrost Thickness”.
68.37, 18.48 (Latnjajaure)
[26]
West to east: 68.42, 18.17
(Katterjåkk); 68.43, 18.34
(Låkta); 68.41, 18.68
(Rackas); 68.36, 18.77
(Heliport); 68.35, 18.85
(Kursflaket); 68.35, 18.87
(Mellanflaket); 68.35,
18.90 (Storflaket); 68.34,
19.00 (Stordalen).
68.36, 18.82 (off ANS)
[50]: Figure 4.
68.36, 18.81 (ANS)
into degree-day
accumulations.
Arithmetic means for
reference periods 19131930, 1931-1960, 19611990, and 1991-2011.
Change is calculated as
difference between
averages across the first
and last periods.
Graph calculated on
decadal arithmetic means
1913 to 2012. With snowfree months considered as
missing values. Overall
change estimated as
(statistically significant)
regression slope.
None
None
None
Mechanical probing,
CALM monitoring
Regression slopes
[19], [173]
Historic data plus ANS
monitoring programme.
[56]: Figure 6, table 2, and
Radiometer measurements,
Overall change estimated
as (statistically significant)
non-linear regression slope.
None
Data from CALM
http://www.gwu.edu/~calm
3
1950 – 1999
Figure 3:
Vegetation
change
text page 9.
ANS monitoring
programme.
Background map: land
cover
Entire region
National Swedish Cadastral
Authorities, Lantmäteriet,
Gävle.
Reference mountain and
vegetation maps.
None
Aspen species line 1904 2009
North-west shores of Lake
Torneträsk.
[32] Figure 1.
Historic literature sources
Tree-ring width aspen vs.
birch, 1900 - 2007
68.33, 18.81 (Paddus area)
[75] Figure 2.
Alder expansion 1977 –
2002
68.42, 18.49 (S2,
Kopparåsen); 68.45, 18.86
(N2, Jibrenluokta)
68.47, 18.71 (N1,
Djupviken); 68.45, 18.86
(N2, Jibrenluokta); 68.51,
18.63 (N3, Pålnoviken);
68.40, 19.11 (N4,
Torneträsk north-shore);
68.31, 18.63 (S1,
Abiskojaure); 68.42, 18.49
(S2, Kopparåsen); 68.36,
18.75 (S3E, Mt. Njulla);
68.34, 18.67 (S3S, Mt.
Njulla); 68.26, 18.60 (S4,
Kaisepakte); 68.26, 19.39
(S5, Nivssakjåkka)
68.48, 18.62 (Pålnoviken);
68.36, 18.78 (Abisko
Tourist Hotel)
[85] Text on page 98 with
Repeat photographic
analysis, field analysis and
dendrochronology
Repeat field survey. Repeat
photographic analysis.
Aspen tree-lines digitised,
geo-referenced, and
transferred to vegetation
map.
Visual estimation.
68.34, 18.88 (north southshore cluster); 68.33, 18.83
(west south-shore cluster);
Tree-line change 1912 2009
Birch forest densification
1906 – 1986
Biomass change 1997 –
positions given in table 1,
page 43.
[16] Two first columns of
table 2, with locations
given in Figure 1.
None
Repeat photographic
analysis, repeat transects
analysis, field
measurements,
dendrochronology.
None
13.
Repeat photographic
analysis.
[82] Figure 1.
Repeat field survey.
Photos renovated and
analysed for birch-forest
content. Degree of change
estimated on a subjective
visual-analogue 0-1 scale
Data were combined into
the six clusters represented
in the map, with min,
[58] Figures 11, 12, and
4
2010
68.33, 18.93 (east southshore cluster); 68.31, 18.89
(south south-shore cluster);
68.46, 18.84 (west northshore cluster); 68.44, 18.89
(east north-shore cluster)
68.36, 18.81 (ANS)
[57]
Repeat field survey of
shrub expansion at the
ANS UV-B control plots.
None.
Tall shrub expansion 1976
- 2010
68.36, 18.75 (Mt. Njulla)
[84] Table 1.
Repeat field survey.
Number of vascular plants
species in understorey,
heath and meadow
communities
[96] Table 1, with
Repeat field survey.
Understorey heath shrub
changes1999 – 2008
68.40, 18.32 (Kärkevagge);
68.36, 18.75 (Mt. Njulla);
68.34, 18.71 (Slåttajåkka);
68.36, 18.76 (Ridonjira);
68.36, 18.80 (Abiskojåkka)
68.36, 18.77 (Abisko
heliport)
Change calculated as the
ratio of species area change
to plot size. Min, mean and
max are, thereafter,
calculated across species
and plots.
Number of vascular plat
species gained and lost per
year.
Understorey shrub change
1991-2006
Heath biomass change
1998 – 2011
68.33, 18.83 (SE of Abisko
village)
68.31, 18.66 (Abiskojaure
outlet)
[95], [96]
Wetland vegetation change
1970 – 2007
68.34, 19.00 (Stordalen)
Alpine heath evergreen
shrub change 1995-2006
63.87, 18.48 (Latnjajaure)
Understorey change 1991 –
2009
mean, and max biomass
change calculated for each
cluster.
locations given in figure 1.
Control plots from in-situ
warming experiment on
heath vegetation.
Repeat survey of vegetation
cover
Repeat survey of plant
biomass.
None.
[53] Table 7.
Repeat colour infrared (IR)
remote sensing and field
survey
[37]
Repeat survey of vegetation
cover
CIR site-classes combined
into hummock, wet sites,
and semi-wet sites (called
others), with average
change calculated per
group.
Expansion ratio based on
primary observations.
[10], [112]
[13] Figure 1c, triangle
curve.
5
Qualitative estimate.
Point estimate of (nonsignificant) regression
slope through time-series of
annual means.
Figure 4:
Impact of rapid
events
Slush torrents
Rain storms
Winter warming event
2007 – 2008
Frost impacts
Autumnal moth defoliation
of birch forest 2004
Lemmings and voles 2000 2012
Moose density 1991 - 2009
68.43, 18.23 (Vassijaure);
68.42, 18.32 (Låktajåkka);
68.40, 18.32 (Kärkevagge);
68.36, 18.75 (Ridonjira)
68.43, 18.13 (Riksgränsen);
68.40, 18.32 (Kärkevagge);
68.40, 18.39 (Låktajåkka);
68.37, 18.47 (Latjnavagge);
68.37, 18.70 (Mt. Njulla);
68.29, 19.23 (Pessijåkka);
68.36, 18.77 (Abisko
valley)
Entire region
[146], [147], [152]
In-situ observations.
Literature study.
None
Jonasson, C., pers obs.
[144], [148], [149],
[150], [151], Jonasson,
In-situ observations.
Literature study.
None
[139] Figure 3.
Remotely sensed NDVI.
68.34, 18.74 (Mt. Njulla);
68.34, 18.77 (Njakajaure);
68.36, 18.77 (Abisko
valley)
Entire region
[71] Table 1 and text
In-situ observations.
Literature study.
NDVI index given in fig. 3
transformed into visualanalogue scale 0 – 1 at
selected locations.
Area of symbol
proportional to area
affected by frost damage.
68.37, 18.48 (Latnjajaure)
Molau, U., pers. obs.
Entire region
[70]
C., pers obs.
section “Frost damage”.
[76] Figure 4.
6
Multi approach: Remotely
sensed NDVI,
literature documentation,
historic temperature data,
birch and pine chronologies. Field surveys
No of individuals caught by
trap in control plots
Annual hunters inventory
Defoliation index given in
fig. 4 transformed into
visual-analogue scale 0 – 1
at selected locations.
none
none