Content uploaded by Wilfried Haeberli
Author content
All content in this area was uploaded by Wilfried Haeberli on Nov 25, 2017
Content may be subject to copyright.
PERMAFROST AND PERIGLACIAL PROCESSES
Permafrost Periglac. Process. 12: 3–11 (2001)
DOI: 10.1002/ppp 377
Permafrost Monitoring in the High Mountains of Europe: the PACE
Project in its Global Context
Charles Harris,1* Wilfried Haeberli,2Daniel Vonder M¨
uhll3and Lorenz King4
1Department of Earth Sciences, University of Cardiff, Cardiff CF10 3YE, UK
2Department of Geography, University of Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland
3Vice Rectorate for Research, University of Basel, Petersgraben 35, CH-4051 Basel, Switzerland
4Geographical Institute, Justus Liebig University, Seckenbergstrasse 1, Giessen D35390, Germany
ABSTRACT
This paper introduces the structure and organization of permafrost monitoring within global climate-
related monitoring programmes. The five-tiered principle proposed for the Global Hierarchical
Observing Strategy (GHOST) is applied to the Global Terrestrial Network for Permafrost (GTN-P)
monitoring system, and the European network of mountain permafrost boreholes established by
the PACE project is discussed in the context of GTN-P. Borehole design and standard PACE
instrumentation are described and some preliminary data from selected boreholes are presented. The
broader research aims of the PACE programme include geophysical investigations, mapping and GIS
strategies, numerical distribution modelling, physical modelling of thaw-related slope processes and
mountain permafrost hazard assessment. Copyright 2001 John Wiley & Sons, Ltd.
R´
ESUM ´
E
Le pr´
esent article d´
ecrit la structure et l’organisation du programme de surveillance du perg´
elisol
et son int´
egration dans les programmes de surveillance du climat. Le principe `
a 5 niveaux propos´
e
pour la strat´
egie d’observation hi´
erarchique (GHOST) est appliqu´
ee au r´
eseau global de surveillance
terrestre du perg´
elisol (GTN-P). Le r´
eseau europ´
een de sondages dans le perg´
elisol ´
etabli par le
projet PACE est discut´
e dans le contexte du GTN-P. La localisation des sondages et l’instrumentation
standard de PACE sont d´
ecrites et quelques donn´
ees pr´
eliminaires de certains sondages s´
electionn´
es
sont pr´
esent´
ees. Les recherches du programme PACE comprennent des recherches g´
eophysiques, des
strat´
egies de cartographie et de syst`
emes d’information g´
eographique, des mod`
eles de distribution
num´
erique, des mod`
eles physiques des processus de versants en relation avec le d´
egel et enfin des
estimations des risques li´
es au perg´
elisol de montagne. Copyright 2001 John Wiley & Sons, Ltd.
KEY WORDS: Boreholes; Europe; mountain permafrost; PACE; thermal monitoring
INTRODUCTION
Permafrost is present at higher elevations within
many of the mountain ranges of Europe, and
is highly sensitive to global climate change. In
December 1997 the European Commission Environ-
ment and Climate Research Programme sponsored
a three-year multinational programme of research
*Correspondence to: Dr C. Harris, Department of Earth Sciences, University of Cardiff, Cardiff CF10 3YE, UK.
E-mail: harrisc@cardiff.ac.uk
Contract grant sponsor: EU Environment and Climate Research Programme; Contract grant number: EnV4-CT97-0492.
Received 10 September 2000
Copyright 2001 John Wiley & Sons, Ltd. Accepted 15 November 2000
4 C. Harris et al.
Janssonhaugen
Svalbard
Tarfala
Juvvashøe
Schilthorn and
Stockhorn Plateau
Stelvio Pass
Veleta Peak
Sierra Nevada
Murtèl-Corvatsch
Figure 1 Location map showing the PACE permafrost borehole monitoring network.
entitled ‘Permafrost and Climate in Europe: cli-
mate change, mountain permafrost degradation and
geotechnical hazard’ (PACE). A critical component
of the PACE project was to establish a transect
of instrumented permafrost boreholes across the
higher mountains of Europe (Figure 1), from Sval-
bard in the north to the Sierra Nevada in the
south (Harris and Vonder M¨
uhll, in press). This
monitoring network forms the focus for complemen-
tary investigations, including geophysical surveys,
microclimatic investigations, numerical modelling of
permafrost distribution, and physical modelling of
permafrost-related slope instability. The aim is to
improve assessment of potential permafrost hazards
in the context of land-use planning and geotechnical
engineering.
The present issue presents some of the first
published outcomes of the PACE programme,
and this paper places the project into its con-
text with respect to global climate monitoring
strategies.
MONITORING THE EVOLUTION OF EURO-
PEAN MOUNTAIN PERMAFROST AS PART
OF GLOBAL CLIMATE-RELATED OBSERV-
ING SYSTEMS
The PACE project is the first coordinated Euro-
pean programme of mountain permafrost monitoring
and measurement. It extends along a north–south
transect from the Mediterranean to the polar lati-
tudes of Svalbard. As in other long-term monitoring
programmes, the goals include improved process
understanding, validation of numerical models, early
detection of potential future changes and assess-
ments of resulting impacts (cf. Fitzharris et al.,
1996; Beniston et al., 1997; Haeberli 1996; con-
cerning snow and ice). The PACE drilling and
borehole observation programme is a contribution
to the Global Terrestrial Observing System (GTOS)
of the Global Climate Observing System (GCOS).
This was established in 1992 by the World Meteoro-
logical Organization (WMO), the Intergovernmental
Copyright 2001 John Wiley & Sons, Ltd. Permafrost and Periglac. Process.,12: 3–11 (2001)
PACE Project in Global Context 5
Oceanographic Commission (IOC of UNESCO), the
United Nations Environment Programme (UNEP)
and the International Council of Scientific Unions
(ICSU). The programme makes systematic and com-
prehensive global observations of key variables to
improve:
(1) detection and quantification of seasonal and
interannual climate change as early as possible
(2) documentation of natural climate variability and
extreme climate events
(3) modelling, understanding and prediction of cli-
mate variability and change
(4) assessment of the potential impact on ecosystems
and socio-economics
(5) strategic plans to diminish potentially harmful
effects and amplify beneficial ones
(6) provision of services and applications to climate-
sensitive sectors
(7) support for sustainable development.
The initial GCOS/GTOS operational system
includes observations of land surface processes and
ecosystems that complement those of the atmosphere
and the ocean. A special Terrestrial Observation
Panel for Climate (TOPC) published version 2.0 of
the plan and defined the minimum set of required
variables for the biosphere, the hydrosphere and
the cryosphere (Cihlar and others, 1997). Many
components of the cryosphere react sensitively to
changes in atmospheric temperature because of their
thermal proximity to melting conditions (cf. Hae-
berli and Beniston, 1998; concerning the European
Alps). Climate projections for the twenty-first century
indicate that there could be pronounced reductions
in seasonal snow, permafrost and glaciers with a
corresponding shift in landscape processes. Imple-
mentation of the cryosphere observations within
the GTOS plan should involve continuation of
existing monitoring programmes for snow, sea ice,
glaciers and permafrost active layer; further devel-
opment of monitoring programmes for ice sheets,
permafrost thermal state and temperatures in cold
firn areas and lake/river ice; and coordination of
an integrated cryosphere monitoring programme,
possibly under the guidance of the International
Commission on Snow and Ice (ICSI/IAHS) and
the International Permafrost Association (IPA). Pri-
orities with respect to initial implementation are
attributed according to climate relevance and feasi-
bility. The following cryosphere variables have been
selected (sea ice is part of the ocean component of
GCOS):
(1) cold firn areas (borehole temperature)
(2) glaciers and ice caps (mass balance, geometry)
(3) ice sheet geometry and surface balance
(4) lake and river freeze-up and break-up (timing)
(5) permafrost (active layer, thermal state)
(6) snow cover area and snow water equivalent.
A Terrestrial Network for Permafrost (GTN-P) was
established to organize and manage a global network
of permafrost observations, most importantly of
changes in frozen ground temperature (Burgess et al.,
2000). Permafrost observations are an important
element of the mission of GCOS because variations
in permafrost temperature can be a sensitive indicator
of climate change and climate variability in remote
areas. For these purposes, observations are required
in both the active layer and the underlying layers
of perennially frozen ground. One of the primary
challenges of the now-launched global observing
systems is to link detailed local measurements for
improved process understanding at one extreme
with global coverage at pixel resolution at the
other. A Global Hierarchical Observing Strategy
(GHOST) has been proposed in order to reach this
goal (World Meteorological Organization, 1997).
Although not developed specifically for permafrost
monitoring, the GHOST strategy is now being
applied to GTN-P, with borehole observations of
permafrost thermal state organized as summarized
below.
Tier 1: Large Transects along Environmental
Gradients
Major, intensive experimental sites should be
designed to emphasize detailed measurements and
process understanding across environmental gra-
dients. They should be located with a primary
emphasis on spatial diversity. Tier 1 sites encom-
pass large experimental areas and various adjust-
ments are required before they can become part of
a long-term monitoring programme. The transition
from intensive field studies to continuous monitor-
ing requires careful planning. Together with other
variables, such as the long-term glacier observations
of the Terrestrial Network for Glaciers (GTN-G:
Haeberli et al., 2000), the PACE borehole network
may eventually form part of tier 1 observations,
being an important high-altitude transect within
the North Atlantic region (Figure 1). This forms a
key area for global atmosphere–cryosphere – ocean
interactions and influences the entire climate
system.
Copyright 2001 John Wiley & Sons, Ltd. Permafrost and Periglac. Process.,12: 3–11 (2001)
6 C. Harris et al.
Tier 2: Extensive and High-Resolution Process-
Oriented Studies of Shallow Permafrost Thermal
State, Energy Fluxes and Surface Controls
Tier 2 sites make possible detailed studies with high
temporal resolution of shallow permafrost thermal
state, energy fluxes and surface controls. Ideally, tier
2 sites should be located near the centre of the range
of environmental conditions (though not necessarily
near the geographical centre) of the zone which
they represent. The actual locations depend more on
existing infrastructure and logistical feasibility than
on strict spatial guidelines, but there is a need to
capture a broad range of climatic zones. Energy-
balance and statistical approaches are applied to
calibrate models relating meteorological and snow
data with the ground temperatures measured, for
instance, at the PACE drill sites (see, for instance,
Hoelzle et al., 2001, this issue). Such models can
then be used for reconstruction of probable past
thermal evolution of permafrost and to predict
permafrost thermal state at depth as a function of
past surface temperatures and possible future climate
scenarios.
Tier 3: Regional Observations of Borehole Tem-
peratures at Intermediate Depths (Depth of Zero
Amplitude and Below) and Regular Time Inter-
vals
Tier 3 sites sample the range of environmental
variation about secular changes within climatic zones
or regions. Borehole measurements at the depth of
zero annual amplitude and below are carried out at
regular intervals of one or a few years. Determination
of temperature gradients and heat flux down to
depths of about 100 m, the standard set for the
PACE boreholes (Figure 2; Isaksen et al., 2001, this
issue), help to estimate secular changes and verify
reconstructions using climate/permafrost models as
developed in tier 2 studies. Numerous potential tier 3
sites exist due to scientific or commercial drilling and
can reflect regional patterns in permafrost thermal
state in both high-latitude lowlands and low-latitude
highlands, but they may not be optimally distributed.
As a result, some regions may have more potential
tier 3 sites than are needed for GCOS/GTOS. Others
may have too few sites or none at all. Therefore,
GCOS/GTOS will need to stimulate efforts to
enhance and balance the network.
0
10
20
30
40
50
60
70
80
90
100
−8.0 −7.0 −6.0 −5.0 −4.0 −3.0 −2.0 −1.0 0.0 1.0
Depth (m)
Temperature (°C)
Stelvio
Juvvasshøe
Janssonhaugen
Figure 2 Geothermal profiles measured at the PACE boreholes: Janssonhaugen (Svalbard) July 1999, Juvvasshøe (Jotunheimen,
Norway), August 1999 and Stelvio (Italian Alps) August 1999.
Copyright 2001 John Wiley & Sons, Ltd. Permafrost and Periglac. Process.,12: 3–11 (2001)
PACE Project in Global Context 7
Tier 4: Sites Where Permafrost Mapping, Spa-
tial Modelling and Geophysical Prospecting Are
Coupled with Measurement of Ground Thermal
Conditions to Provide representative Permafrost
Conditions
At this level, spatial representativeness is the highest
priority. Information about permafrost temperatures
measured in deep boreholes must be extrapolated to
unmeasured areas by mapping permafrost distribu-
tion. This is coupled with ground thermal conditions
derived from tiers 2 and 3 using remote sensing,
spatial modelling and geophysical prospecting tech-
niques (see Vonder M¨
uhll et al., 2001, this issue;
Etzelm¨
uller et al., 2001, this issue; Hoelzle et al.,
2001, this issue). Critical factors involve ice content
and ground materials (such as bedrock, fine-grained
sediments, coarse blocks etc.), vegetation (forest,
tundra, no vegetation cover etc.), topography-related
snow conditions (wind-blown convexities, depres-
sions with increased snow accumulation, removal and
deposition of avalanche snow on steep slopes etc.) as
well as climatic factors (such as solar radiation and
air temperature governing the radiative and sensible
heat fluxes). Keys for such extrapolation and mod-
elling schemes have to be developed in selected test
areas. These test areas, such as the PACE drill sites,
may be closely related to tier 2 and tier 3 studies. The
locations of tier 4 sites should be based on statistical
considerations. However it is impractical to prescribe
one statistical design for all countries. Hence, indi-
vidual participating organizations are responsible for
locating the sites, and could choose either a sys-
tematic or a stratified-random approach. The PACE
drill sites emphasize wind-blown bedrock ridges and
summits with little vegetation. This network should
be complemented by shallow boreholes in ice-rich
sediments on slopes or valley bottoms.
Tier 5: Global Coverage Based on a Combination
of In Situ Measurements, Remote Sensing and
Global Circulation Models or Regional Circula-
tion Models
Satellite observations generally cover areas of <102
to >107m2), while ground observations are point
values. The implementation of tier 5 requires interna-
tional collaboration. The preparation of data products
from satellite measurements must be based on a
long-term programme of data acquisition, archiving,
product generation and quality control. Discussions
are now under way in the Committee on Earth Obser-
vation Satellites (CEOS) to set up such a system.
The main problem concerning permafrost is the con-
tinuing absence of any remote-sensing methodology
providing direct information about ground condi-
tions. Passive microwave radiometry in combination
with the bottom temperature of snow (BTS) effect
(cf. Haeberli, 1978), as investigated within the PACE
project, appears to be promising (Vonder M ¨
uhll et al.,
2001, this issue), but changes related to factors which
control surface conditions (snow, vegetation) may
also be important.
THE PACE PERMAFROST MONITORING
NETWORK IN THE CONTEXT OF GLOBAL
CLIMATE-RELATED OBSERVING SYSTEMS
Long-term monitoring of the permafrost geothermal
regime began in Alaska and northern Canada in the
mid twentieth century (see, for instance, Lachenbruch
et al., 1962; 1966; 1982; Lachenbruch and Marshall,
1969; Taylor et al., 1982; Gray and Brown, 1982),
but similar geothermal measurements have not
generally been made in lower-latitude mountain
regions. The response of permafrost to climate
change was discussed by Gold and Lachenbruch
(1973) and by Osterkamp (1983). Three depth and
time scales are to be anticipated. Firstly, at depths
of several metres, thickening and warming of the
active layer are likely within one to several years.
Secondly, at depths of several tens to hundreds
of metres, a non-linear temperature profile will
develop over a period of many decades in response
to changing upper boundary conditions. Finally,
thawing at the permafrost base and hence thinning of
the permafrost may occur within decades, centuries
or even thousands of years. Since heat advection
by groundwater flow can often be excluded in cold
and ice-saturated permafrost, the temporal change
in geothermal profile in response to changing upper
boundary conditions can be solved simply in terms
of heat conduction. Inversion modelling approaches
therefore allow estimates of surface thermal changes
over time scales of one or two centuries (Vonder
M¨
uhll and Haeberli, 1990; Isaksen et al., 2001, this
issue).
The PACE borehole network established a latitu-
dinal transect of instrumented permafrost boreholes
(Figure 1) to monitor temporal variation in mountain
permafrost geothermal regime over short to medium
time scales (seasonal, annual, decadal). The transect
lies in a geographically important zone in terms of
atmospheric circulation. Detailed energy flux studies
are in progress at each borehole location, together
with related process monitoring, so that the PACE
network fulfils most of the requirements of tiers 1–4
of the GTN-P strategy. First measurements indicate
Copyright 2001 John Wiley & Sons, Ltd. Permafrost and Periglac. Process.,12: 3–11 (2001)
8 C. Harris et al.
that permafrost thicknesses exceed drilling depths at
all sites (see below for details) and are generally
greater than expected. The reduction of heat flow
points to twentieth-century warming which appears
to be comparable with, or even faster than, atmo-
spheric temperature rise. Permafrost warming along
the PACE transect may also be stronger at lower than
at higher latitudes. It will be of interest to compare
such phenomena with snow and glacier data and with
coupled ocean/atmosphere mass and energy fluxes in
the North Atlantic region.
THE PACE BOREHOLE STRATEGY
Site characteristics of PACE boreholes are summa-
rized in Table 1. In order to optimize comparability,
and to ensure that thermal properties were not exces-
sively complex, all PACE boreholes were drilled in
bedrock, in the main in ridge-crest or plateau loca-
tions where winter snow accumulation is minimal.
In all cases 100 mm diameter air flush rotary drilling
was used. The PACE standard borehole depth is at
least 100 m, but since the borehole is protected with a
covering structure at the surface, an additional 20 m
deep borehole is drilled adjacent to the main bore-
hole for measurement of active layer properties under
undisturbed conditions. Boreholes are lined with
plastic tubing and instrumented with standard ther-
mistor strings assembled by F. Stump AG, N¨
anikon,
Switzerland. Negative temperature coefficient ther-
mistors (Yellow Springs Instruments 44006) with a
relative accuracy of 0.02 °C are placed on a Colorflex
CY chain at depths (in metres) of 0.2, 0.4, 0.8, 1.2,
1.6, 2, 2.5, 3, 3.5, 4, 5, 7, 9, 10, 11, 13, 15, 20, 25, 30,
40, 50, 60, 70, 80, 85, 90, 95, 97.5 and 100 m. Ther-
mistor strings may be retrieved from the boreholes
for recalibration and essential maintenance.
Data logging is via Campbell CR21X loggers with
multiplexer (AM416) and storage module card. In
addition, five or more UTL-1 miniature temperature
loggers are installed in the vicinity of the borehole
to record ground surface temperatures and determine
the late winter bottom temperature of snow (BTS).
Finally, test sites are equipped with a meteorological
station close to the borehole recording wind speed
and direction, air temperature and relative humidity,
net radiation and snow height, for use in energy flux
studies.
Preliminary Results
Preliminary thermal data from the three Scandina-
vian PACE boreholes (Janssonhaugen, on Svalbard,
Juvasshøe, in Jotunheimen, Norway; and Tarfala in
northern Sweden) are discussed by Isaksen et al.
(2001, this issue). Short-term and seasonal thermal
changes provide critical data for energy flux-based
geothermal modelling (e.g. Hoelzle et al., 2001, this
issue), while longer-term records over decades will
allow responses to climate change to be detected and
quantified. Since comparable data will be collected at
all boreholes in the transect, future records will high-
light latitudinal differences in geothermal change
and these will be related to climate forcing mecha-
nisms. The longer this record is maintained, the more
valuable it will become. Figure 2 presents thermal
profiles from Janssonhaugen (Svalbard), Juvasshøe
(Norway) and Stelvio Pass (Italian Alps). The thermal
gradient at Janssonhaugen is steepest, and suggests
permafrost depths of around 250 m. The low gra-
dients at Juvasshøe and Stelvio suggest permafrost
depths in excess of 300 m. In all three boreholes, the
thermal gradient decreases towards the surface, pro-
viding consistent evidence for a rise in mean surface
temperatures over the twentieth century (e.g. Isak-
sen et al., 2001, this issue). Application of inversion
modelling to these data and to those of the other
PACE boreholes offers the potential for reconstruc-
tion of surface thermal history over the past century
or more in this north–south continent-wide transect
through the high mountains of Europe.
PERMAFROST MONITORING IN THE CON-
TEXT OF THE PACE PROJECT
The PACE permafrost borehole network is part of
the developing GCOS GTN-P monitoring strategy.
Within the PACE programme itself, boreholes form
the focus of a number of field test sites (see, for
instance, G´
omez et al., 2001, this issue). Here, the
linkage between changing permafrost thermal con-
ditions (derived from borehole data) and resulting
changes in the characteristics and spatial distribution
of permafrost is under investigation. Two key objec-
tives of the PACE programme are: (a) to develop
methods of mapping and modelling the distribu-
tion of thermally sensitive mountain permafrost and
predicting climatically induced changes in this dis-
tribution; and (b) to provide new approaches towards
environmental and geotechnical hazard assessment of
mountain permafrost degradation. These objectives
are addressed through a series of research strategies,
known as work packages.
The PACE work package 1 (WP1) relates to bore-
hole drilling and instrumentation. WP2 is concerned
with geophysical methods and applications to pro-
vide reliable and efficient detection, mapping and
Copyright 2001 John Wiley & Sons, Ltd. Permafrost and Periglac. Process.,12: 3–11 (2001)
PACE Project in Global Context 9
Table 1 Summary of PACE borehole site details.
PACE boreholes Janssonhaugen Tarfala Juvashøe Schilthorn Stelvio Pass Murt`
el– Corvatsch Stockhorn Veleta Peak
and test sites (Svalbard, (Lapland, (Jotunheimen, (Berner (Lombardia, (Oberengadin, plateau (Sierra
Norway) Sweden) Norway) Oberland, Italy) Switzerland) (Wallis, Nevada, Spain)
Switzerland) Switzerland)
Site Latitude 78°1004500N67
°550N61
°4003200N46
°3303400N46
°3005900N46
°260N45
°5901700N37
°0302400N
description Longitude 16°2801500 E18
°380E08
°2200400E07
°5001000E10
°2803500E09
°4903000E07
°4003100E03
°2200500W
Elevation
ASL
275 m 1540 m 1894 m 2900 m 3000 m 2670 m 3410 m 3371 m
Topography Hill Ridge Plateau Slope Summit Rock glacier Plateau on crest Ridge
MAAT 8°C
(estimated)
7°C
(estimated)
4°C
(estimated)
3.7 °C5.5 °C
(estimated)
(Sep. 98 to
Sep. 99)
First
borehole
Drilling date 30 April to 2
May 1998
24– 26 March
2000
1– 4 August
1999
August 2000 1998 May/June 1987 31 July 2000 September
2000
Depth 102 m (vertical) 100 m (vertical) 129 m (vertical) 101 m (vertical) 100.3 m
(vertical)
62 m (vertical) 100.7 m
(vertical)
100 m
(vertical)
Chain length 100 m 100 m 100 C129 m 100 m 100 m 58 m 100 m 100 m
Thermistor
depths
PACE standard PACE standard PACE standard PACE standard 24
(0.02–100 m)
52 (0.6– 58 m) PACE standard PACE standard
Second
borehole
Drilling date 2 May 1998 26 March 2000 4 August 1999 14 October 1998 2 August 2000 September
2000
Depth 15 m (vertical) 15 m (vertical) 20 m (vertical) 14 m (vertical) 31 m (vertical) 15– 20 m
Chain length 15 m 15 m 15 m 13.7 m 17 m
Thermistor
depths
PACE standard PACE standard PACE standard PACE standard PACE standard
Meteostation Installation
date
May 2000 April 2000 September 1999 October 1998 September 1998 1997 September
1998
Sensors Air temperature Air temperature Air temperature Air temperature Air temperature Air temperature Air temperature
Relative
humidity
Relative
humidity
Relative
humidity
Relative
humidity
Relative
humidity
Relative
humidity
Relative
humidity
Wind speed Net radiation Net radiation Net radiation Net radiation Net radiation
Wind direction Snow depth Snow depth Snow depth Snow depth Snow depth
Wind speed Wind speed Wind speed Wind speed Wind speed
Wind direction Wind direction Wind direction Wind direction Wind direction
Responsible
partner
Institute University of
Oslo
University of
Stockholm
University of
Oslo
VAW-ETH
Z¨
urich
University of
Rome
University of
Z¨
urich
University of
Giessen
Complutense
University,
Madrid
Team leader Prof.
J.-L. Sollid
Prof.
P. Holmlund
Prof. J.-L. Sollid Dr D. Vonder
M¨
uhll
Prof. F. Dramis Prof.
W. Haeberli
Prof. L. King Dr D. Palacios
Copyright 2001 John Wiley & Sons, Ltd. Permafrost and Periglac. Process.,12: 3–11 (2001)
10 C. Harris et al.
characterization of mountain permafrost. Two papers
(Vonder M¨
uhll et al., 2001, this issue; Hauck et al.,
2001, this issue) discuss the progress that has been
achieved by this Work Package. WP3 is concerned
with the analysis in a GIS environment of both
remotely sensed data and field mapped data and gen-
eration of maps of permafrost distribution, ground
and environmental conditions. Results from southern
Norway are presented by Etzelm¨
uller et al. (2001,
this issue). Vegetation mapping as an indicator both
of permafrost and near-surface mass movements is
also included.
In work package 4, microclimatological data col-
lected at PACE borehole installations and elsewhere
within the field test sites are being used to formulate
physically based numerical modelling of mountain
permafrost distribution. Digital elevation models are
used to modulate energy flux between atmosphere,
active layer and permafrost (see Hoelzle et al., 2001,
this issue; Gruber and Hoelzle, 2001, this issue).
Once developed, this approach opens the possibility
of predicting changes in distribution under differ-
ent climatic scenarios. WP5 provides a theoretical
link between climatically forced permafrost degra-
dation and slope hazards. The research uses scaled
centrifuge modelling of permafrost slopes. Experi-
ments have investigated slope instability in thawing
soils (Harris et al., 2001a, this issue) and the thermal
sensitivity of frozen bedrock slopes (Davies et al.,
2001, this issue). Finally, WP6 integrates the previ-
ous five work packages in the context of geotechnical
and environmental hazard prediction, to provide new
practical guidelines for the assessment of poten-
tial hazards associated with mountain permafrost
degradation. The aim is to emphasize the potential
impacts of global climate change within the European
mountain permafrost zone in the context of terrain
stability; a first approach is outlined by Harris and
Davies (2001b, this issue).
CONCLUDING COMMENT
The European mountain permafrost zone is sensitive
to climate warming. Permafrost temperatures are
generally only a few degrees Celsius below freezing,
so that even small ground temperature increases may
lead to significant permafrost thaw. Evidence from
Switzerland suggests that warming of permafrost
in the Alps has taken place over the past decade
(Vonder M¨
uhl et al., 1998). The presence of frozen
ground is a vital factor in the stability of mountain
slopes, since, in most cases, thawing leads to loss
of strength and lowering of safety factors. The
PACE project, therefore, seeks not only to monitor
future changes in permafrost temperatures, but also
to predict changes in permafrost distribution, and the
environmental, geomorphological and geotechnical
consequences. This issue presents a series of papers
in which results of the broader PACE programme
are described. It must be stressed, however, that at
the time of writing the project still has six months
to run. During that period, and subsequently, it is
anticipated that further progress will be made in
data collection, analysis and interpretation. This will
lead to more research of importance not only to
permafrost science and engineering, but also to the
broader scientific community concerned with global
climate change.
ACKNOWLEDGEMENTS
This paper describes research funded by the EU Envi-
ronment and Climate Research Programme (DGXII)
under contract ENV4-CT97-0492 ‘Permafrost and
Climate in Europe’ (PACE). The contribution of all
research partners within the PACE programme is
gratefully acknowledged.
REFERENCES
Beniston M, Haeberli W, Hoelzle M, Taylor A. 1997. On
the potential use of glacier and permafrost observations
for verification of climate models. Annals of Glaciology
25: 400–406.
Burgess MM, Smith SL, Brown J, Romanovsky V, Hin-
kel K. 2000. Global Terrestrial Network for Permafrost
(GTN-P): permafrost monitoring contributing to global
climate observations. Current Research 2000-E14,
Geological Survey of Canada, 1–8.
Cihlar J, Barry TG, Ortega GE, Haeberli W, Kuma K,
Landwehr JM, Norse D, Running S, Scholes R, Solo-
mon AM, Zhao S. 1997. GCOS, GTOS Plan for Terres-
trial Climate-Related Observation. GCOS 32, version
2.0, WMO, TD-796, UNEP, DEIA, TR, 97–7.
Davies MCR, Hamza O, Harris C. 2001. The effect of
rise in man annual temperature on the stability of rock
slopes containing ice filled discontinuities. Permafrost
and Periglacial Processes 12: 137 –144.
Etzelm¨
uller B, Ødeg˚
ard RS, Berthling I, Sollid JL. 2001.
Terrain parameters and remote sensing data in the
analysis of permafrost distribution and periglacial
processes: examples from southern Norway. Permafrost
and Periglacial Processes 12: 79 –92.
Fitzharris BB, Allison I, Braithwaite RJ, Brown J, Foehn
PMB, Haeberli W, Higuchi K, Kotlyakov VM, Prowse
TD, Rinaldi CA, Wadhams P, Woo MK, Xie Y, Anisi-
mov O, Aristarain A, Assel RA, Barry RG, Brown RD,
Dramis F, Hastenrath S, Lewkowicz AG, Malagnino
Copyright 2001 John Wiley & Sons, Ltd. Permafrost and Periglac. Process.,12: 3–11 (2001)
PACE Project in Global Context 11
EC, Neale S, Nelson FE, Robinson DA, Skvarca P, Tay-
lor AE, Weidick A. 1996. The cryosphere: changes and
their impacts. Climate Change 1995. Impacts, adap-
tations and mitigation of climate change: scientific-
technical analyses. Contribution of Working Group II to
the Second Assessment Report of the Intergovernmental
Panel on Climate Change. Cambridge University Press:
Cambridge; 241–265.
Gold LW, Lachenbruch AH. 1973. Thermal conditions in
permafrost—a review of North American literature. In
Proceedings of the Second International Conference on
Permafrost, Yakutsk. National Academy of Sciences:
Washington, DC; 3–23.
G´
omez A, Palacios D, Ramos M, Tanarro LM, Schulte L,
Salvador F. 2001. Location of permafrost in marginal
regions: Corral del Veleta, Sierra Nevada, Spain.
Permafrost and Periglacial Progresses 12: 93–110.
Gray JT, Brown RJE. 1982. The influence of terrain factors
on the distribution of permafrost bodies in the Chic-Choc
Mountains, Gasp´
esie, Qu´
ebec. In Proceedings of the
4th Canadian Permafrost Conference, Calgary, Alberta.
National Research Council Canada: Ottawa; 23 – 35.
Gruber S, Hoelzle M. 2001. Statistical modelling of moun-
tain permafrost distribution: local calibration and incor-
poration of remotely sensed data. Permafrost and
Periglacial Processes 12: 69–77.
Haeberli W. 1978. Special aspects of high mountain
permafrost methodology and zonation in the Alps. In
Proceedings of the Third International Conference on
Permafrost. National Research Council: Ottawa; Vol. 1,
379–384.
Haeberli W. 1996. Glacier fluctuations and climate change
detection. Geografia Fisica e Dinamica Quaternaria 18:
191–199.
Haeberli W, Beniston M. 1998. Climate change and its
impacts on glaciers and permafrost in the Alps. Ambio
27 (4): 258–265.
Haeberli W, Cihla J, Barry R. 2000. Glacier monitoring
within the Global Climate Observing System. Annals of
Glaciology 31: 241–246.
Harris C, Vonder M ¨
uhll D. in press. Permafrost and cli-
mate in Europe: climate change, mountain permafrost
degradation and geotechnical hazard. In Global Change
and Protected Areas, Visconti G (ed.). Kluwer: Dor-
drecht.
Harris C, Rea B, Davies M. 2001a. Scaled physical
modelling of mass movement processes on thaw-
ing slopes. Permafrost and Periglacial Processes 12:
125–135.
Harris C, Davies MCR, Etzelm¨
uller B. 2001b. The assess-
ment of potential geotechnical hazards associated
with mountain permafrost in a warming global
climate. Permafrost and Periglacial Processes 12:
145–156.
Hauck C, Guglielmin M, Isaksen K, Vonder M ¨
uhll D.
2001. Applicability of frequency-domain and time-
domain electromagnetic methods for mountain per-
mafrost studies. Permafrost and Periglacial Processes
12: 39–52.
Hoelzle M, Mittaz C, Etzelm ¨
uller B, Haeberli W. 2001.
Surface energy fluxes and distribution models of
permafrost in European mountain areas: an overview
of current developments. Permafrost and Periglacial
Processes 12: 53–68.
Isaksen K, Holmlund P, Sollid JL, Harris C. 2001. Three
deep alpine-permafrost boreholes in Svalbard and
Scandinavia. Permafrost and Periglacial Processes 12:
13–25.
Lachenbruch AH, Marshall BV. 1969. Heat flow in the
Arctic. Arctic 22: 300–311.
Lachenbruch AH, Brewer MC, Greene GW, Marshall BV.
1962. Temperatures in permafrost. Temperature, its
Measurement and Control in Science and Industry 3:
791–803.
Lachenbruch AH, Greene GW, Marshall BV. 1966. Per-
mafrost and the geothermal regimes. Chapter 10 in
Environment of the Cape Thompson Region, Alaska.
US Atomic Energy Commission, Division of Technical
Information: Washington, DC; 149– 165.
Lachenbruch AH, Sass JH, Marshall BV, Moses TH. 1982.
Permafrost, heat flow and the geothermal regime at
Prudhoe Bay, Alaska. Journal of Geophysical Research
87: 9301–9316.
Osterkamp TE. 1983. Response of Alaskan permafrost
to climate. In Final Proceedings, Fourth International
Conference on Permafrost, Fairbanks Alaska. National
Academy of Science: Washington, DC; 145 – 152.
Taylor A, Brown RJE, Pilon AS. 1982. Permafrost and the
shallow thermal regime at Alert, N.W.T. In Proceed-
ings of the Fourth Canadian Permafrost Conference,
Calgary, Alberta. National Research Council Canada:
Ottawa; 12–22.
Vonder M¨
uhll D, Haeberli W. 1990. Thermal character-
istics of the permafrost within an active rock glacier
(Murt`
el/Corvatsch, Grisons, Swiss Alps). Journal of
Glaciology 36: 151–158.
Vonder M¨
uhll D, Stucki T, Haeberli W. 1998. Borehole
temperatures in Alpine permafrost: a ten year series. In
Proceedings of the Seventh International Conference on
Permafrost, Yellowknife, Canada. 1089 – 1095.
Vonder M¨
uhll D, Hauck C, Gubler H, McDonald R, Rus-
sill N. 2001. New geophysical methods of investigating
the nature and distribution of mountain permafrost with
special reference to radiometry techniques. Permafrost
and Periglacial Processes,12: 27–38.
World Meteorological Organization. 1997. GHOST—Glo-
bal Hierarchical Observing Strategy. GCOS-33, WMO
no. 862.
Copyright 2001 John Wiley & Sons, Ltd. Permafrost and Periglac. Process.,12: 3–11 (2001)
