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Interaction between Climate Change
and the Cryosphere
A joint Nordic effort to integrate cryosphere dynamics in ­­
49
Global Earth System
Models
Interaction between Climate Change and the Cryosphere
A joint Nordic effort to integrate cryosphere dynamics in ­­Global Earth System Models
NordForsk, Stensberggata 25, N-0170 Oslo, Norway
www.nordforsk.org
Org.nr. 971 274 255
Editor: Jostein Sundet, NordForsk
Cover: Bødalsbreen Glacier, Norway. Photo: FCG/shutterstock
Design: Jan Neste, jnd
Printed by: 07 Group, august 2016
ISSN 1504-8640
Interaction between Climate Change and the Cryosphere
A joint Nordic effort to integrate cryosphere dynamics in ­­Global Earth System Models
1
Contents
3
4
6
8
Preface
The Nordic Research Collaboration, an example of Best Practices
The main climate challenges and the Nordic countries
Important accomplishments of the ICCC
High impact research findings in the NCoEs
12 [1] Arctic air pollution effects on cryosphere
16 [2] Temperature-albedo response
20 [3] Carbon cycle in a changing Arctic
24 [4] Freshwater and coastal areas
26 [5] Changes in ice dynamics
30 [6] Improving estimates of ice sheet mass changes
34 [7] Ice Nucleation Counter
36 [8] Improvements of Earth System Models (ESMs)
40 [9] Outreach: The Ice School
44 The Top-level Research Initiative
2
Preface
This report by the programme committee summarizes the Nordic
research collaboration in the highly successful Interaction
between Climate Change and the Cryosphere (ICCC) programme
and highlights the international quality research carried out in
three Nordic Centres of Excellence (NCoE):
There has been extensive research cooperation between these
three NCoEs as well as a unique collaboration in developing
graduate schools with cooperative PhD education between Nordic
universities. The report summarizes world-leading research on the
interaction between climate change and the cryosphere – the term
for areas of the Earth where water is frozen – ice on sea, rivers and
lakes, snow cover, glaciers, permafrost and ice caps. Furthermore,
this report shows how the programme enabled Nordic scientists
to bring Nordic cooperation in cryosphere science to a new level,
leading to new integrated research of the cryosphere in our region
and providing a strong foundation for future collaboration at both
the Nordic and the international level.
• Stability and Variation of Arctic Land Ice (SVALI),
• Cryosphere-Atmosphere Interactions in a Changing Arctic
Climate (CRAICC),
• Depicting Ecosystem-Climate Feedbacks from Permafrost,
Snow and Ice (DEFROST).
The Scientific Advisory Board (SAB) mandate was to oversee the scientific quality in the research done in the ICCC sub-programme in TRI.
The SAB consisted of the following members:
• Mark C. Serreze (Chair), Director, National Snow and Ice Data Centre, Professor, Department of Geography, University of Colorado Boulder, USA
• Isabelle Bey, Executive Director, Centre for Climate Systems Modeling, ETH Zurich, Swiss Federal Institute of Technology, Switzerland
• Michiel R. van den Broeke, Professor, Institute for Marine and Atmospheric Research, Utrecht University, The Netherlands
• Philippe Huybrechts, Professor, Earth System Science and Department of Geography, Vrije Universiteit, Brussels, Belgium
• Hans-Wolfgang Hubberten, Professor, Head of AWI Research Unit, Alfred Wegener Institute for Polar and Marine Research, Potsdam, Germany
The programme committee (PC) members are appointed by the funders of the TRI programme. The PC consisted of the following members:
• Magnus Friberg (Chair), The Swedish Research Council • Harri Hautala, Academy of Finland • Kristján Kristjánsson, Reykjavik University
• Herman Farbrot, The Research Council of Norway • Shafqat Abbas Khan, Technical University of Denmark
3
The Nordic Research Collaboration, an example of Best Practices
The people engaged in ICCC, whether they are
­researchers, students, programme committee
­members, non-Nordic science advisors or NordForsk
staff, all agree that this has been an outstanding
­collaboration. Key reasons for this include:
way to address ice and snow on all scales, from nanoscale
processes forming ice nucleus in clouds, to field stations
observing the thawing peat bogs and to global satellite-based
observations of glaciers. Further, there is a need for observation
scientists to work with numerical modellers and computer
scientists to do the parametrization, the algorithms and the
hands-on computer coding.
First, the ICCC involves the very best researchers and institutions
in the Nordic region through a unique common pot funding
model. This makes it possible to base the set-up of the
programme, the calls for proposals and the evaluation more on
what is to be done and who can do it best, than on which country
applicants come from. This is rare in international research
collaboration, where the norm is for each country to support only
its own scientists, apply its own conditions to the funding and, in
the worst case, grant funds only on the basis of its own priorities.
Third, ICCC is part of the Top-level Research Initiative with a
strong political backing. The Nordic Prime Ministers expressed
a common political will to put money into research and
innovation on climate and the environment at the time the
Top-level Research Initiative was launched. Today, the political
support is maintained in the Top-level Research Initiative’s
high-level management board and in the Nordic research
funding organizations of all five countries represented in the
Programme Committee. This enables the Programme Committee
to emphasize all aspects of collaboration within ICCC and, more
importantly, to ensure that the improvements suggested by the
Science Advisory Board are implemented.
Second, working together towards a common and a well-defined
goal has been an important factor driving the cooperation
between institutions and individuals from different disciplines
of research and society. This has made it possible to describe the
focus of the ICCC in one sentence – Integrating the Cryosphere
(snow and ice) dynamics into global climate models.
Finally, the programme builds on a long tradition of Nordic
cooperation based on common history, values and trust. This spirit
of cooperation has enabled joint efforts in many fields of research,
often managed by NordForsk and other Nordic institutions. More
than once, the Nordic way, with common pot funding, has been
highlighted as the best, but unachievable, model of European
cooperation, e.g. in the European Joint Programming Initiatives.
The interaction of frozen water with the rest of the climate system
is complex and involves poorly understood feedbacks on many
geophysical, biological and societal scales. There is a need for
specialists from many fields of science to work in an integrative
4
The Nordic Prime Ministers at the Riksgränsen ski resort in Sweden 2008, where they drew up the Riksgränsen Declaration which laid the foundation for the largest
joint Nordic effort to promote research and innovation ever undertaken, focusing on climate, energy and the environment, later known as the Top-level Research
Initiative (TRI): Geir H. Haarde, Jens Stoltenberg, Anders Fogh Rasmussen, Fredrik Reinfeldt, Matti Vanhanen. Photo: Johannes Jansson/norden.org
The Programme Committee emphasizes that the successful model
of Nordic research cooperation must be continued and that the
ICCC programme can serve as an example of how to bring this
cooperation to the next level. The successes of ICCC, with a rather
modest amount of funding, high impact results and best practices
in research collaboration, all point forwards to a new research
programme that will build upon this success.
5
The main climate challenges and the Nordic countries
The Nordic countries are part of the Arctic, an area where
cryosphere processes are prominent and which is already much
affected by climate change. Emissions of greenhouse gases and
air pollution cause rapid changes in the Arctic cryosphere and
accelerate Arctic and global warming, and thus have a direct
impact on the Nordic societies. Through the ICCC programme,
the Nordic countries jointly invest to understand the cryosphere
– including permafrost, snow, glaciers and sea ice – and its
inter­­actions with the Earth System. A better description of the
mechanisms acting on the Arctic cryosphere, climate system
and ecosystems improves the Earth System Models, leading to
better predictions of future climate change and its impacts on
our societies.
The NCoEs address three of these (melting land ice, sea level
changes, clouds and climate sensitivity), and the knowledge
gained in these efforts will provide new important input to the
sixth IPCC assessment report (probably due in 2020/2021).
The NCoEs also have assessed and defined several future
challenges of key importance relating to future climate
challenges identified by the WCRP and IPCC:
• Understanding and describing new, central physical
processes in the climate system (ice, ocean, land,
atmosphere and interaction between these).
• Improving projection of rapid changes, in particular for ice
sheets and reducing the uncertainty of mass changes of the
Greenland Ice sheet.
Themes such as the melting of ice and thawing of permafrost,
as well as aerosols, cloud forming processes sea level rise are
studied in the NCoEs and have provided new and important
insight over the five years the NCoEs have been active.
• Understanding the origin and variability of natural and
anthropogenic aerosols, and quantifying their impact on the
Earth system.
Many challenges remain to be addressed for the years to come.
As identified by the World Climate Research Programme (WCRP)
and repeated in the last IPCC report, these may be categorised
in five science areas:
• Understanding the change of uptake of carbon in the
biosphere.
• Understanding the role of freshwater in the ocean circulation
in the Arctic region.
• Melting land ice
• Sea level change
Nordic countries are major contributors of scientific knowledge
in these fields and will continue to offer insight in the future, in
part thanks to the ICCC programme.
• Fresh water availability
• Climate extremes
• Clouds and climate sensitivity
6
Important results of the ICCC programme are:
• Has conducted experiments and modelling related to sea
spray aerosol and its climate impact in a changing Arctic
climate. Temperature has to be considered in the air-sea
exchange.
• Highly successful in the education and training of PhD
students and Postdocs in the field of Earth System Sciences
and provided efficient networking frameworks for the young
scientists.
• Mass and energy exchange has been parameterized based on
long term observations for all major vegetation types in the
boreal and Arctic biomes.
• It is essential to find ways to maintain and develop the Nordic
leadership that it has now established.
• Knowledge of emissions of marine aerosols, including sea-salt,
DMS and organic compounds has progressed considerably.
• Has brought Nordic cooperation in cryosphere-climate science
to a new level.
• All glaciology-related courses held at collaborating
university are now mutually recognized by the other member
universities.
• New use of data from satellites (GRACE, ICES at and Cryosat-2)
has been ground-breaking, facilitating better understanding of
the mass balance and surface elevation changes.
• The use of neural networks to fill gaps in methane flux data
time series
• Innovative work in glacier hydrology, ice velocity mapping
over Svalbard and Greenland
• Progress in the research on glacier volume changes in the
20th Century, glacier hydrology, calving mechanism and
implementation and coupling of glaciers in Earth System
Models.
• Has addressed the high sensitivity of Arctic climate to black
carbon emissions compared to middle latitudes.
• Building of the Nordic Ice Nucleus Counter.
7
Important accomplishments of the ICCC
The ICCC was initiated as a direct response to the identified
need to better understand the cryosphere and changes in it and
to parametrize cryosphere processes. This comprises important
input to global climate and Earth System Models (ESMs) used
by the Intergovernmental Panel on Climate Change (IPCC) to
assess the future changes to the Earth’s climate system. In
addition to this, ICCC seeks to increase the scientific quality,
efficiency, competitiveness and visibility of the Nordic
cryosphere research via collaboration within the Nordic region
and beyond, e.g. by supporting and educating early career
scientists – the next generation of earth system scientists.
The ICCC programme has fostered a high number of PhD
students and Postdocs, of which 1/2 and 2/3, respectively, came
from non-Nordic countries. The NCoEs provide an outstanding
research environment for PhDs and Postdocs. This is evident
in the fact that many new young scientists have been trained
and are now playing leading roles in a number of applications
for national, Nordic and international (EU) competitive
research funds. The new PhDs and Postdocs will also have
impact on science in the future, as many of these have an
interdisciplinary focus.
8
The Nordic countries have long been well represented in
international collaboration and networks. One very tangible
example is the number of Nordic researchers actively involved
in writing and editing the IPCC fifth assessment report, as
well as the number of Nordic contributions to the Coupled
Model Inter-comparison Project Phase 5 (CMIP5). The number
of scientific papers published in high profile journals and the
overall high visibility of the NCoEs is further proof of their
international scientific and societal impact.
9
High impact research
findings in the NCoEs
[1-9]
10
SMEAR2 Photo: NordForsk/Terje Heiestad
11
[1] Arctic air pollution effects on cryosphere
12
Holtedahlfonna glacier, The Exilfjellet-tre Kronor mountain komplex, central-western Spitsbergen. Svalbard. Photo: Erlend Bjørtvedt (CC-BY-SA) /Wikimedia commons
13
[1] Arctic air pollution effects on cryosphere
Black Carbon (BC) is a fine particle formed by incomplete
combustion, often from the burning of fossil fuels or forests.
Due to its colour and unlike most aerosols, BC absorbs visible
light and warms the atmosphere. The warming effect of BC
is intensified in the Arctic where it decreases the surface
reflectivity of snow and ice, also called albedo, and hastens
their melt. Despite its importance for Arctic climate change,
little is known about BC loadings in the area and its effect on the
albedo. Since the beginning of the ICCC programme, significant
progress in BC studies is achieved.
pollution are likely situated within the Arctic. This is particularly
alarming since BC emitted at high latitudes will more easily
make its way to snow and ice surfaces, resulting in a strong
warming response. This was also shown in an ESM study, which
investigated the contribution of BC emitted in mid- and north
latitudes to temperature change in the Arctic. For example, BC
emitted from gas flaring in northern Russia results in a fivefold
temperature response in comparison with BC transported from
mid-latitudes to polar regions.
Black carbon and dust originating from surrounding ice-free
areas also affect the melt of ice sheets and glaciers. However,
the role of the particle life cycle on and within the ice remains
unclear. A novel model framework was developed to study the
transport of black carbon within the ice, including the seasonal
burial in snow, transport within the ice and melt out in summer.
The result shows that the release of black carbon from the ice
accelerates the melting of ice sheets.
In a series of unique experiments, two types of soot from
burning of oil and wood were artificially deposited on natural
snow surfaces. The experiments show that soot deposited onto
a snow surface reduces the snow albedo. Furthermore, a new
hypothesis that BC in the melting snow reduces its density was
presented and confirmed. Less dense snow is less reflective and
melts faster. Therefore, BC (Black Carbon) deposition enhances
the snow-albedo feedback - one of the important drivers of the
Arctic warming.
An ice core from Svalbard covering the last 300 years, was
studied as a part of the ICCC program. It revealed that BC
increased in the ice core during the last few decades (Fig. 1).
Independent lake sediment records from northern Finland
showed similar trends. This work questions the previous general
concept of a recent decline in the anthropogenic air pollution
in the Arctic. Moreover, the main sources of the observed
14
Svalbard, Holtedahlfonna
BC concentration (μg L-1)
100
80
60
40
20
0
1700
1750
1800
1850
1900
Figure 1. Black Carbon concentrations in the Holtedahlfonna, Svalbard ice core during the last 300 years.
The red line represents 10-year averages.
15
1950
2000
Year
[2] Temperature-albedo response
Norbert Pirk was a doctoral student at Lund
University and the University Centre in Svalbard
(UNIS). He used flux chambers and other
advanced technical equipment to study the
production of methane and CO2 in the
tundra on Svalbard.
16
DEFROST, Svalbard. Photo: NordForsk/Terje Heiestad
– Based on past interviews,
students have been very positive
about the project.
17
[2] Temperature-albedo response
Seasonal snow is very important for the radiation in the Arctic
due to its high albedo. According to laboratory experiments,
snow albedo is stable at temperatures below -10 °C and
decreases when temperatures rise above -5 °C. Such studies
are widely used to describe snow properties in models, but
they might not represent atmosphere-cryosphere interactions
realistically. Recent analysis of satellite measurements of spring
snow-covered land surfaces in high latitudes showed that
surface albedo decreases already at -10 °C and even -15 °C in
some regions (Fig. 4). Moreover, this finding indicates that some
areas in the Arctic are more sensitive to warming and, therefore,
can exhibit climate changes faster.
18
Arctic Archipelago
Northern continental Canada
Albedo, unitless
Labrador Peninsula
Albedo, unitless
–15°C
0.8
Albedo, unitless
–10°C
0.8
0.7
0.7
0.7
0.6
0.6
0.6
0.5
0.5
0.5
0.4
0.4
0.4
0.3
0.3
-30°C
-20°C
-20°C
0°C
10°C
–10°C
0.8
0.3
-30°C
-20°C
-20°C
0°C
10°C
-30°C
-20°C
Figure 2. Relationship between surface air temperature in spring and albedo of snow-covered land for three regions in the Arctic. Albedo decreases at much lower
temperatures than predicted from laboratory experiments.
19
-20°C
0°C
10°C
[3] Carbon cycle in a changing Arctic
“NordForsk should continue to fund the NCoE program, or something
similar to it, in the future. The model is fundamentally sound. By providing a
mechanism focused largely on supporting graduate students and Postdocs
and promoting student mobility, the effort appears to have advanced Nordic
research and collaboration between Nordic nations. In general, the three
centres under the ICCC have been able to leverage ‘base’ funding provided
by NordForsk to result in greater scientific productivity.”
– SAB report 2016.
20
Kevo National Park, Finland. Photo: NordForsk/Anne Riiser
21
[3] Carbon cycle in a changing Arctic
It has been shown that the melting sea ice impacts
soils far inland. When the sun-reflective sea ice cover
is retreating due to rising temperatures, the dark
open seawater absorbs energy from the sun which
leads to a regional increase in air temperature. As a
result, permafrost can thaw in nearby land and this
subsequently leads to these areas releasing more
methane, causing a positive feedback loop in the climate
system (Fig. 3). Whereas the thawing of land permafrost
is readily visible today, the subsea permafrost thaws
much slower.
Figure 3. Simplified representation of Arctic carbon fluxes that are influenced by sea ice retreat. On land,
plants take up carbon while microorganisms in the soil produce methane and respire CO2. In the ocean,
methane is released from thawing subsea permafrost, while CO2 is absorbed due to an under-saturation
of CO2 in the water compared with the atmosphere. The arrows do not represent the strength of each flux.
Numbers at the top of the figure represent estimated uptake/release of carbon (Tg carbon / year).
22
In a warming Arctic, as the thawed layer of carbon-rich soil
thickens, microbial activity is boosted, and the production of
greenhouse gases accelerates. Soil characteristics along with
climate and permafrost data are being documented in detail,
to understand the geochemical processes behind the response
of the carbon cycle to climate change. To help determine
feedback-increased soil carbon emissions, ICCC researchers also
contributed to a new pan-arctic inventory of carbon content in the
upper 3 m of soil (Fig. 4)
This is particularly relevant in lowlands where the soil coverage
is thick and rich in carbon. In mountainous areas, where the soils
are thinner and hold less carbon, increased temperatures lead to
increased vegetation cover and, thus, an uptake of carbon from
the atmosphere.
Arctic plant communities will likely change under a warmer
climate. Predicted increases in snow cover will play an
important role, influencing the length of the growing season,
permafrost and hydrology. To investigate how increased snow
cover thickness and duration affect plant photosynthesis, an
experiment with snow fences was set up in two sub-arctic tundra
vegetation types. Thickness of snow increased in the test plots,
and the cover lasted longer in spring. Under these circumstances,
plants were more efficient in light use and photosynthesis. This is
likely due to more moisture and nutrients in the soils as there is
more water and permafrost thawed. There was also an observed
vegetation shift towards more grasses since dry areas get wetter.
Figure 4. Soil organic carbon pool (kg C m−2) contained in the 0–3 m depth
interval of the northern circumpolar permafrost zone. Points show field site
locations for 0–3 m depth carbon inventory measurements; field sites with
1 m carbon inventory measurements number in the thousands and are too
numerous to show.
23
[4] Freshwater and coastal areas
Large amounts of terrestrial organic carbon from coastal
erosion in the East Siberian Arctic Shelf and Russian-Arctic
rivers are released into near coastal waters. This carbon can
be converted into greenhouse gases, but it can also be buried
in sediments and thereby slow down the carbon climate
feedback. In close collaboration with Russian scientists, ICCC
researchers contributed to the SWERUS expedition in 2014
on the research vessel ODEN to the Laptev Sea to study these
phenomena to further understand the role of carbon from
runoff and erosions in the Arctic sea.
The amount of freshwater coming from melting glaciers is
likely to increase as glaciers are retreating, which may affect
the nearby fjords and continental shelves. Observations in
a fjord in West Greenland in 2013 showed that meltwater
increases uptake of CO2 from the air, especially during summer
time. Fresh meltwater blends into the fjord water leading to
an under-saturation in CO2. Moreover, it causes upwelling
of nutrients that feed the biological system which in-turn
increases the productivity that demands more CO2.
24
Lake Pielinen, Finland. Photo: Stocksnapper/Shutterstock
25
[5] Changes in ice dynamics
“Interaction between Climate Change and the Cryosphere is a ­
sub-programme under the Top-level Research Initiative (TRI), a unique
Nordic venture for research on climate, energy and the environment.
International research collaboration is a necessity to increase the quality
and excellence of research, and the ICCC is an excellent example of the
best practices of Nordic research groups doing high impact science on
the international arena of climate and cryosphere science.”
– SAB report 2016.
26
Austfonna, Svalbard. Photo: Michael S. Nolan AGE/NTB/scanpix
27
[5] Changes in ice dynamics
Svalbard, Austfonna
Northing
UTM33X (km)
16
16
12
12
8900
8860
Basin-3
8820
2
50m contours
Drainage basins
Easting UTM33X (km)
700
740
5
cm.day
Apr 30 to May 11, 2012
Rapid acceleration of mass loss observed in glaciers in both
Greenland and Antarctica in recent years is believed to be due
to changes in glacier dynamics. However, many aspects of
the response of ice sheet and glaciers dynamics to a warming
climate are poorly understood as well as underrepresented in
models. Long-term observations of surface velocities by ICCC
partners on glaciers around the North Atlantic reveal changes
caused by the flow of meltwater at the glacier bed.
8
8
4
4
2
-1
0
0
Velocity (m day−1)
Jan 30 to Feb 10, 2013
A dramatic surge at the Austfonna ice cap in Svalbard in
2008–2014 involved a multi-annual acceleration (Fig. 5). At
the beginning of each summer, the glacier velocity increased,
but instead of going back to its winter normal flow, the glacier
moved continuously faster than previous years until the surge
occurred in 2014. The surge propagated the acceleration to
the whole basin, and is believed to be caused by lubrication
of the glacier bed. Modelling of the ice cap confirmed that
28
5
cm.day
-1
Cummulative Positive Degree Day (°C)
Horizontal velocity
(m day−1)
200
6
100
0
GPS 4
GPS 5
GPS 3
GPS 2
GPS 1
4
2
0
July
January ‘09
July
January ‘10
July
January ‘11
July
January ‘12
July
January ‘13
Figure 5. Basin surge at the Austfonna ice cap, Svalbard the LEFT MOST inset shows
the location of Austfonna. IN ADDITION, on the LEFT SIDE, velocity maps are presented
for early May 2012 and early February 2013. The RIGHT INSET describes cumulative
surface melt (red bars) and surface velocities (lower part of inset).
the conditions at the glacier bed dramatically changed over
a period of only a few months before surging. In Iceland,
similar acceleration of glaciers is observed during outburst
floods originating from geothermal subglacial lake. The results
show that water flow at the glacier bed controls variations in
surface speed. Monitoring surges in Svalbard and outburst
floods on Icelandic glaciers thus provides an opportunity to
study processes that may determine the future of ice sheets in
Greenland and Antarctica.
29
[6] Improving estimates of ice sheet mass changes
“It is the view of the SAB that
the major ICCC objectives have been
met and that NordForsk funding
has been invested wisely.”
30
Drangajökull, Iceland. Photo: Gregory Gerault, Hemis/Alamy Stock Photo
31
[6] Improving estimates of ice sheet mass changes
Monitoring the elevation of ice sheets and glaciers was brought
to a new level with the launch of the CryoSat-2 and Landsat 8
satellites. Researchers from the ICCC collaborated with ESA and
NASA to calibrate elevation signal from CryoSat-2 and thereby
significantly improved the measurement accuracy of glaciers
mass changes.
Drangajökull
1946-1960
1960-1975
Past mass balance of glaciers was also analysed using archived
aerial photographs as old as from the 1930’s. Innovative
photogrammetry techniques were used to calculate the surface
elevation of glaciers with high accuracy from analogue images.
These data are important for understanding the past response
of glacier to climate variations, and validating models that are
used to make future predictions.
Figure 6. The average annual elevation change of Drangajökull during six
intervals since 1946. Red indicates thinning and blue thickening.
32
1975-1985
1985-1994
1994-2005
33
2005-2011
[7] Ice Nucleation Counter
“Through the end of the project, the centres
continued to collaborate, particularly between
projects CRAICC and DEFROST that have broadly
similar interests. The successful e-science proposal
(eSTICC), involving collaboration between DEFROST,
SVALI and CRAICC is notable in this regard, and will
help in maintaining science productivity after the
sunset of NordForsk funding for the NCoEs.”
– SAB report 2016.
34
Clouds. Photo: NordForsk/Terje Heiestad
[7] Ice Nucleation Counter
Clouds in the Arctic can either cool the atmosphere by reflecting
incoming radiation back to space, or warm it by trapping heat
emitted by the earth surface. The scientific community is still
working on understanding the key process related to the cloud
formation in cold climates - ice nucleation that initiates cloud
development. Ice nucleation is the phase transition from water
to ice when seed particles, such as aerosols, are present. Ice
Nuclei Counters are instruments that measure these particles.
aimed at direct observation on ice nucleation properties of
Arctic aerosol particles. Enthusiastic specialists were brought
together to further the ice nucleation research, which remains
a major unsolved problem in atmosphere physics. When the
instrument will be ready for installation and data collection,
it will be deployed at Nordic and Arctic research stations. This
will promote scientific understanding of ice cloud formation
and evolution from microscopic to global scale, and will help to
describe ice nucleation processes in climate models.
Until recently, no Ice Nuclei Counters existed in the Nordic
region, whilst worldwide none of the existing instruments
were routinely deployed in the polar domains. A technology
sharing agreement adopted in 2012 by ICCC partners and
European colleagues from ETH Zurich and Leibniz Institute for
Tropospheric Research made it possible to boost ice nucleation
research by building the first Nordic Ice Nuclei Counters
35
[8] Improvements of Earth System Models (ESMs)
36
Melting water and sea, Greenland. Photo: NordForsk/Jostein K. Sundet
“While the projects have led to may new
collaborations, collaborations take time to
develop, and as such, the full fruits of the ICCC
NCoE effort will not be fully realized
until perhaps years from now.”
– SAB report 2016.
37
[8] Improvements of Earth System Models (ESMs)
ESMs are useful tools to study feedback cycles because they
enable analysis of system behaviour as a whole. Representation
of the climate components however remains imperfect and new
knowledge is constantly being implemented into ESMs.
refreezing of meltwater at the surface of the Greenland ice sheet
and Svalbard glaciers contributed to better understanding of the
formation of ice layers and snow hydrology. The effect of snow
albedo was also assessed in a regional climate model of Svalbard
using observations from Lomonosovfonna ice cap. The results
were used to improved snow parameterizations in the EC-Earth
(European Centre for Earth) ESM.
The dynamic vegetation-terrestrial ecosystem model LPJ-GUESS
has been customised for northern ecosystems to study Arctic
carbon balance. The model investigates the vulnerability of
high-latitude peatlands to climate change as well as feedback
processes that could modulate regional and global climate
change. Further, the upgrades are expected to be implemented
into a regional climate model.
There has been a great Nordic value with respect to experiments
and modelling related to sea spray aerosol and its climate
impact in a changing Arctic climate. The work has demonstrated
that the effect of temperature on air-sea exchange should be
addresses in the future.
The updated GIPL permafrost model is now integrated into a
regional climate to perform simulations of sub-sea as well as
land-based permafrost that were lacking before.
An ice sheet model is now integrated into the EC-Earth ESM.
This model has been run until year 3000 following a type of
“Business as usual” scenario, where high greenhouse gas
emissions continue and peak in the early 22nd century.
Even though greenhouse gas concentrations are levelling off
after year 2200, the simulation shows that the mass loss of the
Greenland Ice Sheet will continue with the same rate for the
following centuries (Fig. 7). Changes in ice mass (i.e., in form
of elevation changes and fresh water input to the ocean) will
lead to large scale changes in the atmospheric and ocean
circulation. This will then affect temperature and precipitation
on the ice-sheet and so its surface mass balance. It is therefore
important to include feedback mechanisms caused by ice sheet
dynamics for long future climate projections.
Boreal ecosystems respond to the warming by emitting more
gaseous compounds into the atmosphere. These can modify the
aerosol concentration. Aerosols impact cloud formation, -lifetime, -albedo, and other processes, affecting radiative balance,
and can therefore potentially amplify or damp the effect of
climate change. The NorESM1-CRAICC Earth System Model was
developed to quantify these processes and improve predictions
of future climate state.
Until very recently, Earth System Models had a highly simplified
representation of snow physics, including refreezing of meltwater
and snow albedo, and they did not integrate dynamic ice sheet
models. Within the ICCC, ground-breaking observations of
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The Greenland ice sheet changes
3600 m
3300 m
3000 m
2700 m
2400 m
2100 m
1800 m
1500 m
1200 m
900 m
600 m
300 m
0m
Pre-industrial
RCP8.5 ( Year 2350-2379)
Figure 7. Modelled Greenland ice sheet
thickness averaged over a 30-year period
from the pre-industrial control as well as
two periods (2350-2379 and 2840-2869)
simulated based on the “Business as usual”
scenario.
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RCP8.5 ( Year 2840-2869)
[9] Outreach: The Ice School
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SVALI, Greenland. Photo: NordForsk/Terje Heiestad
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[9] Outreach: The Ice School
The Ice School is an online learning platform that will
inform the public and teach about glaciology and climate
change (Fig. 8). Developed for students aged between 12 and
14, the website offers interactive and pedagogic information
on the science of ice and provides a forum to exchange
knowledge between teachers and researchers. The Ice
School is available in all the Nordic languages as well as in
English, German and French.
NordForsk has produced films and a book, Solving the
Climate Crisis – A Nordic Contribution , about the TRI where
the ICCC centres of excellence are presented.
Greenland. Photo: NordForsk/Jostein K. Sundet
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Figure 8. The Ice-School website, an educational online platform about ice and climate. http://isskolen.dk/wp/?page_id=8102
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The Top-level Research Initiative
Nordic Centre of Excellence CRAICC
CRAICC objectives have been to identify and quantify the major
processes controlling Arctic warming and related feedback, in
addition to outlining strategies to mitigate Arctic warming, and
develop Nordic Earth System modelling.
Head of CRAICC: Professor Markku Kulmala,
University of Helsinki
The Nordic Top-level Research Initiative (TRI) is the largest
Nordic research and innovation venture to date and is within the
topics of climate, energy and the environment. It was launched
by the five Nordic Prime Ministers in 2007.
The TRI was targeted as a Nordic flagship initiative at the
Copenhagen Climate Change Conference (COP15) in Copenhagen
in 2009 with the aim of contributing to the global knowledge
base within climate-related issues and challenges.
All three centres have a large number of partner institutions in
all of the Nordic countries, PhD students and courses.
The ICCC was one of six sub-programmes under the Top-level
Research Initiative and had three Nordic Centres of Excellence:
The TRI has been evaluated by the independent consultancy
firm DAMVAD, and their main conclusion is that the TRI has
produced important scientific results and provided a major
contribution to the Nordic research effort in the areas of climate,
energy and the environment.
Nordic Centre of Excellence SVALI
The aims of SVALI were to develop more precise estimates of
how fast the glaciers in the Arctic are melting, and to better
understand the processes related to the speed of melting and the
influence on hydrology and the dynamics of the ice.
Head of NCoE SVALI: Professor Jon Ove Hagen, University of Oslo
Nordic Centre of Excellence DEFROST
DEFROST has gathered internationally recognized experts
with the goal of understanding how changes in the cryosphere
caused by climate change influence the ecosystem/geosphere
processes trough changes in the Methane and CO2 stored in the
soil, which directly affect climate.
Head of DEFROST: Professor Torben R. Christensen,
Lund University
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