Download Earth System interactions

Earth System interactions: enhancing capabilities for the
prediction of global, regional and local climate change - a
Nordic window of opportunity
A white paper on a proposed Nordic network in Climate and Earth System Modelling
Co-ordinating authors
Jens Hesselbjerg Christensen1, Trond Iversen2,8, Colin Jones3, Heikki Järvinen4 and
Markku Rummukainen3,23
Contributing authors
Andreas Ahlstrøm5, Bjørn Ådlandsvik6, Lars Bärring3,23, Claus Beier7, Terje Berntsen8,
Halldór Björnsson9, Jørgen Brandt10, Deliang Chen11, Helge Drange12,17, Karin Edelvang13,
Eirik Førland2, Hans-Christen Hansson14, Christoph Heinze15, Kim Holmén16, Øystein Hov2,
Eystein Jansen17, Tómas Jóhanneson9, Eigil Kaas18, Erland Källén19, Leif Klemedtsson11, Jon
Egill Kristjansson8, Nils Gunnar Kvamstø15, William Lahoz20, Ari Laaksonen4, Joakim
Langner3, Gerrit de Leeuw4,21, Kari Lehtinen4,22, Anders Lindroth23, Jørgen E. Olesen24,
Haraldur Olafsson9, Anders Omstedt11, Jens Christian Refsgaard5, Anna Rutgersson25, Ben
Smith23, Árni Snorrason26, Anders Stigebrandt11, Johan Strömqvist3, Andreas Stohl20, Frode
Stordal8, Gunilla Svensson19, Michael Tjernström19, Peter Tunved14
1
Danish Climate Centre, Danish Meteorological Institute
Norwegian Meteorological Institute
3
Swedish Meteorological and Hydrological Institute
4
Finnish Meteorological Institute
5
Geological Survey of Denmark and Greenland
6
Institute for Marine Research, Norway
7
RISØ, Technical University of Denmark
8
Department of Geosciences, University of Oslo, Norway
9
Icelandic Meteorological Office
10
National Environmental Research Institute, University of Aarhus, Denmark
11
Tellus, University of Gothenburg, Sweden
12
Nansen Environmental and Remote Sensing Centre, Norway
13
DHI, Denmark
14
Department of Applied Environmental Science, Stockholm University, Sweden
15
Department of Geophysics, University of Bergen, Norway
16
Norwegian Polar Research Institute
17
Bjerknes Centre for Climate Research, Norway
18
Niels Bohr Institute, University of Copenhagen, Denmark
19
Department of Meteorology, Stockholm University, Sweden
20
Norwegian Institute for Air Research
21
Department of Physics, University of Helsinki
22
Department of Physics, University of Kuopio
23
Department of Physical Geography and Ecosystems Analysis, University of Lund, Sweden
24
Faculty of Agricultural Sciences, University of Aarhus, Denmark
25
Department of Meteorology, University of Uppsala
26
National Energy Authority, Iceland
2
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Vision
Collectively, Nordic research is in a position to extend the frontiers of climate research,
towards a new generation of models that will allow climate prediction with unprecedented
spatial detail and process accuracy. This will enable both policy-makers and stakeholders to
better use emerging scientific findings for mitigation and adaptation strategies, to tackle
environmental risks likely to dominate the political agenda in the 21st Century and beyond.
Primary research goals
To achieve a balanced mitigation and adaptation to climate change, there remains an urgent
need to narrow down uncertainties that are central to assessing future impacts of climate and
environmental change. In particular, it is presently not possible to set an accurate upper bound
on the climate response to increasing greenhouse gas emissions1. This uncertainty arises from
a poor understanding of and ability to model key cloud feedback processes and aerosol-cloud
interactions, as well as deep ocean water formation and its role in the global ocean
thermohaline circulation. Earth System feedbacks that are presently represented only in a
rudimentary manner in climate models, may also add significantly to this uncertainty.
We are ready to attack such key research challenges, for which the collective Nordic research
community holds world class excellence. In particular our efforts will be targeted at:
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an advanced modelling platform emphasizing major Earth System components for
assessing multi-decadal and century-long climate change and associated risks;
projections of regional to local climate with unprecedented spatial detail.
enabling systematic research on the impacts and implied consequences for
infrastructure and physical planning of future changes to: the hydrological cycle, the
cryosphere, a range of biogeochemical cycles, sea level and extreme weather events.
Strategic mission
A broad and committed large-scale collaboration will enable Nordic researchers to both
develop and utilize a shared set of world-leading climate modelling tools, for use in policyrelevant climate prediction and impact assessment. It will further support training of the next
generation of Nordic interdisciplinary environmental scientists. Our mission is thus to:
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accelerate and expand Nordic research efforts in climate change, along with strong
linkages to climate change impact assessments and strategies for adaptation;
organize an interdisciplinary Nordic science network, dealing in particular, with
specific Arctic and Nordic climate research issues while also making a major
contribution to international research;
couple the Nordic research communities (climate modelling, climate observations,
climate impacts, and adaptation) with planners and local managers at international,
Nordic, national and municipality levels;
provide relevant guidance for managers and policy makers dealing with adaptation
(regional and local climate change) and with mitigation (global long-term change);
drive advanced education and training on Earth System Science and Global Change,
leading to a new generation of interdisciplinary Nordic Earth System Scientists.
1
For example, the IPCC AR4 report states that it is very unlikely (<10% chance) that the equilibrium climate
sensitivity is less than 1.5oC, but only likely (>67% chance) that it is smaller than 4.5oC. There is a considerable
risk (>10% chance) that the value is above 6oC. The value of the climate sensitivity has direct consequences for
mitigation efforts and urgency. To limit global warming in some given way, such as the 2°C limit adopted by the
European Union, a larger climate sensitivity will imply smaller allowable accumulated emissions.
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Summary
This document motivates a strengthened Nordic collaboration, that can develop the next
generation of Earth System Models (ESM) for climate prediction that: (i) are reliable; (ii)
encompass the key climate processes pertaining to the Nordic and Arctic regions; (iii) include
an improved description of processes that are presently considered to be highly uncertain; (iv)
are computationally efficient; (v) possess advanced diagnostic tools for a detailed evaluation
of model components; and (vi) provide better regional and local information to impact
assessments, policy-makers and society at large.
Global Earth System Modelling is highly complex and computationally intensive, requiring a
broad multidisciplinary approach. Presently, modelling groups in the Nordic countries are
integrally involved in a number of international consortia developing Global ESMs, and are
thus at the forefront of this field. Through collaboration in these large consortia the enormous
resources of the international community are made available for the benefit of predicting
climate change over the Nordic region. To best utilize these efforts requires closer
collaboration between the relevant Nordic groups, with improved exchange of knowledge,
models and simulation results. Why and how this can be done is the essence of this document.
In the Nordic and Arctic regions there are numerous specific processes that are likely to
provide strong feedbacks to external climate forcing, both local to the region but also
remotely, with clear consequences for future climate evolution. Some of these processes are
among the most poorly described components of present-day climate models. To better
understand, model and evaluate such processes, requires a means of bringing the complexity
of Global ESM approach down to the Nordic-Arctic regional scale. Integration of a broader
range of natural processes into a unified Earth System Model will enable quantitative
assessments of a wider range of environmental impacts of climate change. Representing
processes with higher resolution will also reduce important uncertainties in climate change
projections. To achieve this necessary progress on both complexity and resolution, we
propose a strengthened collaboration between Nordic groups that already possess a high level
of expertise in understanding the relevant processes, assessing observations, and modelling
the climate from global to local scales.
The Nordic community has a very high standing in the international Regional Climate
Modelling community, having some of the most advanced Regional Climate Models (RCMs)
in the world. Global ESMs need to be complemented by regional and local climate prediction
techniques, in order to support localized assessment of the impacts of climate change. We
thus plan to bring together the entire Nordic community engaged in Earth System Modelling,
as well as data and impact studies, to develop a joint Nordic-Arctic Regional System Model,
applicable at high resolution (1-5km) with specific emphasis on key Nordic-Arctic processes.
To significantly expand the frontiers of Nordic Earth System Modelling, along with impact
and adaptation research, is an ambitious effort. The key to a successful collaboration is
resources, both in terms of highly-qualified personnel and computational facilities. This effort
must encompass all the intellectual capacity in the Nordic countries. Furthermore, such an
effort will require increased computational capacity, advanced model development, training
of new scientists, as well as outreach and policy contacts. To achieve a major advance in each
of these areas requires a significant and long-term investment, in parity with recent Nordic
Centres of Excellence; i.e. ~300-400 MDKK over a 5-year period, with a similar level of
funding for a subsequent 5-year period, once significant progress has been demonstrated.
The time is right for such an initiative, which will enable us to attack some of the major
challenges of climate change with an adequate research effort, to support the development of
mitigation and adaptation strategies with suitable efficiency and urgency.
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The way forward
The challenges and opportunities to radically advance Nordic climate research efforts touch
particularly upon Earth System modelling and high-resolution climate prediction, with strong
links to impact assessment, outreach and policy support. Advances in Earth System Science
will lead to improved support for Nordic efforts on the development of suitable adaptation
and mitigation strategies, as well as on climate politics and international collaboration.
Compared to physical climate models, Earth System Models (ESMs) include explicit
descriptions of a far greater number of natural processes, supporting a much wider range of
impact assessment studies than traditional climate models. Significantly increased model
resolution, both globally and regionally over the Nordic-Arctic region, will also contribute
greatly to an improved ability to simulate key physical climate processes, as well as extreme
weather events.
To make significant progress in Earth System Modelling that will lead to tangible
improvements in the reliability of climate projections over the Nordic-Arctic region, requires
a revolution in the Nordic Earth System Sciences. The complexity of ESMs urgently calls for
increased collaboration with a multi-disciplinary approach, bringing together the climate
modelling community, observationalists and process modellers. It is critical that a continuous
level of interaction and intellectual exchange occurs between physical climate modellers,
terrestrial and ocean ecosystem modellers and computer scientists, as well as experts in the
fields of biogeochemistry, hydrology, glaciology, sea-ice and permafrost. At the Nordic level,
most of these individual elements already exist, but without an overly strong representation in
any single country and little organized collaboration.
With respect to developing a high-resolution, Nordic-Arctic Regional System Model, the
Nordic science community must organize itself to address this challenge, both as a
contribution to international efforts to address global change, but also to provide reliable
estimates of future climate over the Nordic-Arctic region. Such a task can only be addressed
by the Nordic Earth Sciences community, who possess the local process and modelling
knowledge along with the observation base necessary to make progress in this endeavour.
To achieve such a revolution requires a significant increase in, and coordination of funding. A
Nordic programme must be ambitious enough to bring together a critical mass of intellectual
diversity to collectively advance Nordic Earth System Science and training, while retaining
the necessary public and policy relevance.
The way forward that we would like to explore, is to initiate discussions over the coming
months, with Nordic and national research councils, government authorities and universities,
regarding the need for an organized and coordinated effort in Earth System Modelling
involving all relevant scientists and stakeholders across the Nordic region.
We wish to emphasize that the Nordic climate research community is keen to develop a joint
effort to provide a significant climate science contribution both for the Nordic and Arctic
regions. Furthermore, we emphasize that the Nordic Earth System Modelling and Global
Change community, through such a proposed consortium, will be better placed to provide
reliable and policy-relevant information on future climate and environmental change, at
unprecedented spatial scales from local to global arenas. This will increase our ability to
interact with and support Nordic and international efforts in climate impact assessment,
adaptation and mitigation.
The remainder of this paper motivates in more detail the need for a new Nordic Network in
Earth System Modelling. It further describes the science foci for such a network, the likely
partners and an initial estimate of the personnel and infrastructure costs of such a network.
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Introduction
Climate change is the environmental and socio-economic grand challenge of our and future
generations. The results of climate models make a large impact on society, as witnessed by
the power of the latest IPCC Assessment on the public and political agenda. Despite recent
advances there is a growing recognition that much research and development is still required.
This has multiple dimensions. One is that important aspects of the climate system are missing
or represented only in a rudimentary manner in contemporary models. This fundamentally
limits our ability to narrow down uncertainties related to anthropogenic climate change,
particularly with respect to setting a reliable upper limit to the sensitivity of the climate
system to increased greenhouse gas forcing. Another dimension is the gap between demand
and provision of relevant information on regional and local climate for use in developing
sustainable adaptation strategies.
Climate modelling is the backbone of climate prediction efforts. Climate models to date
describe the physical and dynamical components of the coupled climate system, with detailed
descriptions of the atmosphere, ocean, snow/sea-ice and land surface. Over the past two
decades climate models have improved enormously, both in their ability to represent climate
processes and in computational efficiency. Nevertheless, there are still many approximations
in the representation of key processes in these models. Many of these approximations are
associated with the cycling of water in the climate system, in particular (1) cloud feedbacks;
(2) aerosol-cloud interactions; (3) feedbacks related to ice and snow. The water cycle is also
central to a wide range of anticipated impacts of climate change. In addition, there are a range
of important biogeochemical processes, which are presently represented only in a rudimentary
manner.
It is now recognized that a more complete description of the cycling of key gases and
nutrients in the Earth System, along with a better treatment of the complete water cycle, is
required to improve our ability to simulate future climate and environmental conditions. As an
example, inclusion of a fully interactive carbon cycle, including sources, sinks and exchange
processes between the oceans, terrestrial biosphere and atmosphere is required to achieve a
reliable estimate of future concentrations of atmospheric carbon dioxide. Similar requirements
hold for other radiatively active gases such as methane, ozone and nitrous oxide. To achieve
an accurate representation of such biogeochemical cycles requires both an improvement in the
accuracy of the simulated physical climate in models, along with inclusion of key
biogeochemical processes. This leads to the development of Global Earth System Models
(ESMs) from what were formerly (physical) Global Climate Models (GCMs). This effort has
begun within a number of large international consortia, to which Nordic countries actively
contribute. It is, however, necessary to consider a trade-off between the need for extended
process complexity with respect to biogeochemical processes in ESMs and the need for better
spatial resolution in the description of key climate processes. Not least clouds and cloud
dynamics, as well as mixing processes in the oceans, all of which are heavily parameterized
due to the small spatial scales involved. As a consequence, there are at least two categories of
sustained global climate model simulation; high-resolution (10-100km) climate predictions
with some basic ESM complexity, and lower-resolution (200-300km) Earth System
simulations with increased complexity.
On regional and local scales, changes in the statistics of extreme weather events, associated
risks, and their impact on society remain to be quantified. The present low level of
understanding on regional and especially local scales, is in part due to lack of sufficient
computational resources to support high-resolution modelling of sufficient complexity.
Observational and theoretical process studies are also required to advance our understanding
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and thereby support advanced model development. To provide climate information of direct
relevance to governments, society and business, global simulations or predictions need to be
transposed to regional and local scales. The most comprehensive mechanism for this is by
means of a Regional Climate Model (RCM) embedded within a Global Climate Model.
Concurrent with the need to address the Earth System on the global scale, there also exists the
need to develop the capability to perform high-resolution regional earth system modelling.
This is also the case in the Nordic countries, with specific reference to key Nordic and Arctic
processes. In summary, there is an urgent need to develop a Regional System Model, which
combines both high-resolution (1-5km), with an advanced description of the key processes
influencing the response of the Nordic-Arctic climate and environmental systems to global
change.
An important link between results from climate and Earth System models and the design and
development of strategies for adaptation and mitigation, is impact assessment. Developing
well targeted societal adaptation strategies requires knowledge of the nature of physical
impacts and ecosystem responses, with higher spatial detail than present global climate
models can provide. In order to motivate meeting the financial costs of mitigation, it is also
necessary to emphasize the benefits of reducing the impacts of climate change. Climate
research in the Nordic countries has been, and continues to be, heavily focused on providing
input to impact and adaptation studies. Our proposal to develop and utilize the most advanced
Global and Regional Earth System Models will greatly increase the quality, breadth and
spatial detail of climate change information that will be available to the Nordic impact and
adaptation community. Higher resolution models will bring the simulated information much
closer to the spatial scales of concern to this community, while the increased breadth of Earth
System processes included in future models will open a wider possibility to study the
integrated impacts of climate change, across a range of coupled environmental sectors. The
members of this proposed consortium, both on a personal and institutional level, already have
a wide and established network of collaborations within the Nordic impact and adaptation
community. We plan to increase this collaboration network substantially around the provision
of high-resolution earth system information and look forward to an intense collaboration with
parallel initiatives within the Nordic impacts research community.
Why Nordic Earth System modelling?
The carbon cycle is a very important component of climate change. The changing buffering
capacity of the ocean and the biosphere for CO2 in a warming world is an issue of
fundamental importance with respect to the development of effective mitigation strategies.
Release of methane in thawing permafrost is another such issue. Ocean acidification due to an
increasing concentration of CO2 within the ocean, along with the response of the nitrogen
cycle, both on land and in the oceans, are all factors that may have a large impact on the
future evolution of the Earth System in relation to climate change. From a Nordic perspective,
deep water formation in the North Atlantic and its role in oceanic carbon buffering, as well as
the role of boreal forests in both the regional and global earth system are issues requiring
increased attention. The role of land-based vegetation further links to nitrogen cycling and
fertilization, the water cycle, as well as the carbon cycle. The nitrogen cycle also links to
tropospheric ozone and thus the overall climate forcing. With increasing summer droughts,
high levels of ozone may add nonlinearly to the negative effects of depleted soil water on
vegetation. There are further links to aerosols and their duality with respect to climate and
health/environment effects. Uncertainties with respect to the role of changing atmospheric
aerosol loading, particularly its interaction with cloud microphysical processes are presently
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the largest single source of uncertainty in global warming projections for the 21st Century.
Furthermore, the reduction of global aerosol loading over the past 20 years is recognized to
have the potential to speed up the global warming trend associated with increasing CO2
concentrations. Of special interest for the Arctic is that, so-called short-lived pollutants
(mainly black carbon and ozone) and methane, through various feedback mechanisms may
influence the Arctic climate proportionally more than was originally envisaged. This has
resulted in policy discussions to curb the emissions of key species in northern regions. The
present level of understanding of the relevant Arctic-specific processes is, however,
insufficient for a reliable quantification of the benefits of emission reductions
Up to now, many of these aspects of the Earth System have been studied in isolation. This has
suppressed the ability to understand potential links and feedbacks across all components of
the full Earth System and a reduced ability to fully sample all potential feedbacks in the
system. An increased Earth System Modelling capability is absolutely necessary to proceed
beyond this rudimentary state of knowledge, thereby increasing the reliability of future
climate simulations. The extreme complexity of Earth System Models needed to address this
range of issues, requires a well organized Nordic collaboration, particularly to develop a
Regional Nordic-Arctic System Model, but also to make a strong contribution to larger
international efforts.
State-of-the-art: Nordic regional climate models
Past Nordic climate modelling research has had a strong focus on regionalization of global
climate change projections. The aim has been to support studies on impacts of climate change
and, increasingly, on adaptation. These activities started out at the Danish Meteorological
Institute around 1995, in the SWECLIM programme in Sweden (presently at the Rossby
Centre, SMHI) and in the RegClim programme in Norway (presently NorClim), around 199798. Activities in Finland and Iceland are also well established, and focus on various impacts
and key climate processes. Throughout these activities, there has been extensive international
collaboration.
Initially Nordic RCMs were predominantly atmospheric models coupled to land surface
models with rudimentary vegetation. The Danish activities at DMI have been based on the
HIRHAM RCM, in co-operation with the Max-Planck-Institute in Germany. At met.no, the
same model was set up for Norway and coupled to a regional ocean model. The Rossby
Centre model RCA at SMHI has been developed from the operational HIRLAM weather
prediction model. The RCA is today extended with an interactive module for the Baltic Sea
and being complemented with interactive vegetation. The Nordic RCMs are also being
applied over a number of other regions of the world, such as the Arctic, where fully coupled
Arctic Regional climate scenarios are now being produced. The Nordic RCMs are, in terms of
quality and complexity, among the very best in the world.
State-of-the-art: Nordic global modelling activities
A sub-Arctic position, with the North Atlantic Ocean to the west and the Arctic Ocean to the
north, has always been important for framing Nordic climate modelling activities and
warranted the development of global modelling capabilities. Initially, DMI co-operated with
and used the ECHAM models developed at the Max-Planck-Institute for Meteorology. In
Norway there was a strong focus on issues with potentially strong relevance to the region,
such as the Atlantic Ocean meridional overturning circulation (AMOC) and aerosol-cloud
interactions. At the Bjerknes Centre for Climate Research, the Bergen Climate Model (BCM)
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delivered a full contribution to the IPCC AR4. In parallel, aerosols and clouds were included
in a dedicated version of the NCAR climate model (CAM-Oslo), a version of which
(CCSM3) is also used at the Rossby Centre of the SMHI, at MISU, the University of
Stockholm and at Tellus, University of Gothenburg.
At present, Nordic groups contribute to three major international ESM consortia; A common
Norwegian global climate model/ESM is under development at the national level in the
NorClim project, with strong links to the development of the CCSM model at NCAR in the
United States. Sweden and Denmark are partners within the EC-Earth project, a multinational European initiative to develop a coupled prediction system from the ECMWF
forecast model, spanning weather prediction to centennial climate timescales. In Finland,
activities are linked to the COSMOS ESM activity, coordinated by the MPI for Meteorology
in Germany.
Why a common Nordic ESM activity?
The main reason for proposing a common Nordic ESM activity is the existence of a large, but
distributed pool of high-level competence within a range of ESM fields. Nordic countries are
integrally involved in three major international consortia developing Global Earth System
Models. This facilitates Nordic access to a pool of international expertise at the forefront of
efforts to develop Earth System Models. However, only the forging of a much closer
interaction between the involved Nordic groups can fully bring the resources available in
these consortia to the concentrated benefit of climate prediction for the Nordic and Arctic
region. Furthermore, the development of a high-resolution, Nordic-Arctic Regional System
Model will only be addressed by the Nordic science community. This effort requires a large
degree of coordination across all the potentially contributing institutes. Present activities in
the Nordic countries will be considerably strengthened by better sharing and coordination of
knowledge, models and simulation results. This will lead to a critical mass being achieved in
several of the major scientific and technical areas at the forefront of Earth System science and
applications. It will further benefit Nordic research if there is a shared computational
infrastructure, software and computer expertise, data management facilities as well as
outreach and training activities. A number of these Nordic partners have been, and are,
involved in past and present European efforts to homogenize and better organize climate
modelling activities across Europe (e.g. the ENES and PRISM initiatives being 2 examples).
Developing a closer collaboration between all Nordic ESM groups will lead to a stronger and
more coordinated Nordic contribution to European and international efforts aimed at
improving our ability to model the Earth System and its response to greenhouse gas emissions
and land-use change.
The main elements of the common Nordic activity
Four elements are necessary for a sustained Nordic Earth System Science initiative: first, a
computational platform with sufficient capacity to support the most advanced Earth System
Models in the world; second, a strong network among all Nordic Earth System scientists;
third, a strong university involvement to train the next generation of Earth System Scientists
and, fourth, an outreach and information activity to support knowledge transfer and decision
making in the Nordic countries.
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A common Nordic Computational Infrastructure
To advance Nordic competence in Earth System Science requires a computational platform
with world-class capacity and capability. A common resource will promote networking and
coordinated production of climate projections for both national and Nordic-Arctic needs.
Technical arguments support a joint climate computing platform: to avoid inadequate and
costly data transfer links, to facilitate code sharing and to provide efficiency at a reduced cost.
A common infrastructure also enables support and incorporation of a wide range of Nordic
university groups, allowing students to receive training on the most advanced modelling
systems.
The new capacity should be sufficient for an advancement of computational climate
modelling in areas such as; increased resolution, new ESM components, increased simulation
length, and ensemble simulations. This calls for a computational resource of the order of
several 100 teraflops of sustained computing power and a data storage capacity in the
petabyte range2.
The Human network (A Nordic Earth System Science community)
It is necessary to establish a true Nordic Earth System Science community. Currently, some
Nordic collaboration exists, but it is almost in parity with the very small common resources
available. Our common culture, established mobility of scientists within the region and
networks funded by the Nordic Council of Ministers do add activity beyond the level of core
national funding. Nevertheless, far more extensive contacts and networks exist today within
the European and US communities than within the Nordic countries. A regional network of
Earth System Modelling efforts would, in particular, support a wide variety of Nordic and
Arctic specific impact and adaptation research in related disciplines, including social,
economic and political sciences.
Outreach and training
Basic and applied research efforts are the foundation for decision-making and planning for
climate change. However, the science has to get across to the users, and the user needs to
research, only then will research efforts directly benefit society and relevance to users and
stakeholders be truly ensured. Building on existing expertise within the Nordic countries in
communicating climate change results to the public, government and a range of stakeholders,
we envisage a major outreach component on dissemination and communication.
Training is an integral part of our envisioned collaboration. The Nordic community must raise
the next generation of researchers, capable of addressing future challenges in Earth System
Science. This requires a strong university involvement, along with a willingness of the main
government agencies to be involved in training students in the use and development of
advanced Earth System Models. Training also needs to involve users and stakeholders so as to
inform them of both the benefits and limitations of Earth System Models within their own
fields of concern.
2
Teraflops = one trillion or 1×1012 FLoating point Operations Per Second, which is a measure of a computer’s
performance.
Petabyte= one quadrillion or 1×1015 bytes, a unit of data such as stored in a climate model simulation.
Both of these measures are an order of magnitude or more beyond present Nordic climate modelling facilities,
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A joint Earth System Modelling strategy
Global Modelling Strategy
We propose that Nordic efforts in Global Earth System Modelling, that benefit from and
contribute to wider international collaborations, are collected around a coordinated common
agenda. This will facilitate better use of key expertise and an increased focus on questions
pertinent to the Nordic-Arctic region.
Earth System Models are highly complex and involve interacting processes that are still only
on the edge of being fully understood. More than ever, it is imperative for the scientific
community to join forces to make progress in this challenging arena. This involves the need to
have a variety of global modelling systems, as there is no single best way of representing the
inherently non-linear and complex global climate system in a single approach. Using a variety
of high-quality global models will provide an estimate of the uncertainty range inherent in
predicting future climate, facilitating a probabilistic approach to the question of future risks. A
coordinated Nordic ESM network will allow easy exchange amongst partners of climate
change simulations from 3 of the world’s leading global ESMs. Furthermore, in a less
complex setting, the same models can be set up with significantly higher resolution
emphasizing physical climate system processes. In particular, a range of phenomena related to
the water cycle (aerosol-cloud interactions, cloud feedbacks, ice and snow feedbacks, and
freshwater forcing of the global thermohaline ocean circulation), all of which impact on
climate predictability on decadal and longer timescales, will benefit from such an approach.
Processes in the middle atmosphere, such as climate impacts of ozone recovery and increased
stratospheric water vapour, are also important in this connection. This approach is needed
along with that of the complex ESM in order to reduce the considerable uncertainties in
estimating climate sensitivities, both on decadal and longer timescales.
Regional and Local Modelling Strategy
We propose that the entire Nordic community engaged in Earth System Modelling, process
understanding and evaluation, jointly develops a common Nordic Regional System Model.
This model will build on the considerable expertise already available in the Nordic countries
and will be specifically developed for application at very high-resolution (1-5 km spatial
resolution), emphasising the key processes in the Nordic-Arctic region. Combined with the
spectrum of Global ESMs which the Nordic community is actively engaged in, a highresolution Nordic-Arctic Regional System Model will offer an unprecedented level of
detailed, high-resolution estimates of future climate and environmental conditions over the
Nordic-Arctic region. Such a Regional System Model will fully engage the wide spectrum of
government and university researchers engaged in modelling, observational and theoretical
studies related to Earth System Science around a single common platform, putting the Nordic
countries at the forefront of Earth System Science. Furthermore, such a modelling system will
attract highly-qualified scientists from other countries to the Nordic region to work on Earth
System Modelling and will constitute a community modelling system, through which the next
generation of Earth System scientists can be trained.
Science foci
Some of the open questions with respect to understanding the future evolution of the climate
system are simply not possible to answer with present day capabilities. To accelerate progress
requires a major leap in research efforts. We identify the following focus areas for Nordic
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ESM research and development, chosen so that they are of particular importance to the Nordic
and Arctic regions, as well as being highly policy relevant:
•
Aerosols and their interaction with radiation and the freshwater cycle, with a particular
emphasis on aerosol-cloud-radiation interactions;
•
Processes in the ocean bodies surrounding the Nordic region. In particular, the North
Atlantic and Arctic Ocean, Norwegian and Greenland Seas, the Barents Sea and the
Baltic Sea, including sea-ice, terrestrial freshwater inputs and biogeochemical/water
quality issues;
•
Land-use and land-use change with emphasis on the Baltic Sea region, Arctic and subArctic including snow, permafrost, wetlands and boreal forests;
•
The carbon cycle with interactive vegetation and ocean biogeochemistry, along with
associated biogeochemical cycles that strongly interact with, and influence, the carbon
cycle;
•
High-impact weather events, particularly those related to strong wind and intense
precipitation;
•
Boundary layer processes, including interactions with boundary layer clouds, large
scale dynamics and surface exchange processes, with a particular emphasis on stably
stratified conditions.
•
Advanced evaluation of model processes through data assimilation, regional water
cycle budgets, lagrangian transport assessment, in situ and remote sensing data.
Data Accessibility
An important aspect of a Nordic collaboration is more efficient access to both observational
and modelling data. This bears on detection and attribution efforts, model evaluation and
development, assessing uncertainties and transposing scientific results into relevant
information for users. In order for this to become efficient, common data policies, data
management and handling are crucial. One priority is to establish an inventory of available
model and observational data, and ease access to these. Defining needs for additional data,
and strategies to meeting these needs is an integral part of the proposed network.
An open consortium
Advantages of working together in an interdisciplinary environment can become undermined
if too strong regulations are enforced on the consortium. Collaboration that builds on mutual
reliance and confidence enables the participants to jointly profit from links with collaborators
also outside the core Nordic effort. It is important to see this collaboration as an addition to a
wider Nordic strategy in Earth System modelling, rather than an obstacle to present progress.
We envisage that the network will consist of a number of core centres from each country,
interacting closely around the development of a common set of modelling tools. On a national
level, the core centres will collaborate with their respective networks of Earth System Science
groups. Direct collaboration between Nordic expert groups in a given Earth System Science
discipline will be strongly encouraged, although it will be important to ensure that results
emanating from these multifarious links feed back into the common Nordic modelling system
for the benefit of all participating groups.
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Foreseen resources
Substantial new funding is envisaged for a Nordic-Arctic Climate Change and Earth System
Modelling network.
For the required computational capacity, outlined above, an investment of the order of 100120 MDKK is necessary. Furthermore, to maintain such a capacity at the forefront of
international facilities requires an investment of similar magnitude roughly every 5 years.
This level of investment will clearly be conditional upon a detailed international peer-review
process. Such a facility also requires funds for general operations and maintenance, along
with technical and application support.
In order to establish a research community requires that all partners are truly engaged in
establishing and maintaining such a network. In addition to a shared vision, this translates into
dedicated resources, including qualified personnel. We envisage, as a minimum, support for
20-25 full-time postdoctoral or research scientist level positions, located at the main
modelling centres. These scientists would each work on the dedicated common Nordic ESM
agenda. An overall project leader will also require support from a full time project
coordinator, to handle day-to-day management and coordination issues. Furthermore, a fulltime position managing network outreach and information dissemination is seen as crucial.
Along with model development and application efforts, a parallel training track is needed.
Full benefit from an interdisciplinary network will only be achieved once an educational
programme is an integral part of the network. We envisage a PhD programme with around 3040 PhD projects, run by university partners, with tight links to the main modelling centres.
In summary, the staff to be involved would be around 20-25 postdoctoral or research scientist
level positions, 30-40 PhD students, 4-5 technical staff, one Project Manager and one
Information Officer. This would be equivalent to approximately ~45 MDKK per year. Some
of the partners’ senior staff commitments need also to be covered, although sizeable in kind
contributions can be foreseen.
Outreach activities will include regular stakeholder meetings to discuss results and research
agendas; Policy briefings; Scientific meetings and workshops with public access; Maintaining
a critical dialogue with media and experts; Development of TV documentaries as well as
debates. Such outreach activities would require additional funding of ~2 MDKK per year.
A suggested overall programme cost (in MDKK) for a five-year period.
2009
2010
2011
2012
2013
Total
Computing facility, incl electricity etc and technical staff
85
45
5
5
5
145
Senior staff (excl in kind contributions)
10
10
10
10
10
50
Postdocs/Research Scientists (science)
20
20
20
20
20
100
PhD students (training and science)
15
15
15
15
15
75
Programme administration and common activities
2
2
2
2
2
10
Outreach, including Information Officer
3
3
3
3
3
15
Total
135
95
55
55
55
395
In order to establish a common platform with a broad shared Nordic knowledge base, a
minimal time frame for the project to be realised is 10 years: an initial 5 years with a further 5
years based on a successful mid-term review of network activities.
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The partners in Earth System Science
Denmark
In Denmark climate and Earth System modelling using comprehensive computationally
demanding models, is mainly taking place at the Danish Climate Centre at DMI. Here
developing, maintaining and utilising global and regional models have been central for more
than a decade. The centre now contributes to global ESM efforts through the EC-Earth
consortium (e.g. technical development, coupling, atmosphere, stratosphere, ocean, and
terrestrial cryospheric modelling development). University partners with Earth System
modelling activities include different institutes at the Copenhagen University (global
modelling, hydrology, ice sheets, terrestrial cryosphere), the National Environmental
Research Institute (NERI) at Aarhus University (ocean and atmospheric modelling, soot and
other aerosols, Arctic boundary layers and chemistry), DHI (urban water resources,
hydrology, lakes, streams and estuaries plus shallow waters around Denmark). Faculty of
Agricultural Sciences at the University of Aarhus also has relevant activities on agricultural
system modelling. The Geological Survey of Denmark and Greenland (GEUS) is a formal
partner with DMI on aspects of climate research on the development of the Greenland Ice
Sheet, but strong collaboration on linkages between climate and hydrological modelling and
climate impact assessments on water resources are also evident. Activities towards a better
understanding of the terrestrial carbon cycle and climate feedbacks are strongholds at
RISØ/Technical University of Denmark and represent a collaborative link with DMI.
Finland
Earth system modelling activities are coordinated by the Finnish Meteorological Institute
(FMI) as a major contribution to the COSMOS ESM network, led by the Max Planck Institute
for Meteorology, Germany. In Finland, Earth system modelling builds on dedicated in-situ
observations of key climate variables and expertise on related climate processes.
Observational stations, such as Pallas-Sodankylä and Hyytiälä, are operated by Universities of
Helsinki and Kuopio, FMI and Finnish Environmental Institute. Scientists from these
institutes form a collaborating core group for Finnish Earth system modelling. In Finland,
there is special expertise on atmospheric aerosols, clouds and radiative transfer, terrestrial
biosphere and soil processes, and on computational aspects of coupled systems (especially at
the Centre for Scientific Computing).
Iceland
In Iceland, Earth System Modelling and research is mainly carried out in close collaboration
between the University of Iceland, the Icelandic Meteorological Office and the Institute for
Meteorological Research. There is an ongoing collaboration on hydrological and glaciological
aspects with the Hydrological Service and on agriculture with the Agricultural University and
the National Forest Service. Ocean research is hosted at the Marine Research Institute and to
some extent also at the Icelandic Meteorological Office and the University of Iceland. The
Iceland group has concentrated on processes on regional to local scale, including dynamic
downscaling and modelling at high resolutions. In Iceland, there is special expertise on
processes related to mountains, including high-resolution temporal and spatial variability in
weather and climate, glaciers and hydrological processes. There is also ongoing research in
atmosphere-ocean interactions and their impact for the climate and the ocean at regional
scales.
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Norway
Climate modelling in Norway is mainly organized in a virtual centre: The Norwegian Climate
Centre, which involves The Bjerknes Centre for Climate Research, Norwegian
Meteorological Institute, Institute for Marine Research, Norwegian Polar Institute, Dep. of
Geosciences at University of Oslo, Cicero – Centre for Climate Research, the Nansen
Environmental and Remote Sensing Centre and the Geophysics Institute at the University of
Bergen. In this virtual centre a global climate model / ESM is presently being developed.
Activities at Norwegian Institute for Air Research (NILU) are relevant, as well as
international co-operation (e.g. National Center for Atmospheric Research in USA). Foci are
on the fresh water cycle, aerosols and clouds, atmospheric chemistry, sea-ice, snow and
cryospheric processes, deep ocean circulation and carbon cycling, land-surface modelling and
biogeochemistry. Middle and upper atmospheric processes are studied off-line. Regional
climate modelling involves global time-slices, regional dynamical downscaling, empirical
downscaling, and statistical adjustments to local features. Model diagnostics include land data
assimilation for evaluating land surface parameters, use of water tracers in regional climate
models, Lagrangian modelling, and remote sensing and in-situ observation of meteorological
variables, cloud characteristics, aerosols, and atmospheric trace gases.
Sweden
The central Swedish climate modelling partner is the Rossby Centre at SMHI, excelling in
coupled regional climate modelling (e.g. coupling strategies, high resolution modelling, land
surface and terrestrial biosphere processes, sea ice, ocean biogeochemistry, clouds/radiation)
and also contributing to global ESM efforts through the EC-Earth consortium (e.g. technical
development, modular coupling, sea ice modelling, cloud/radiation parameterization and
decadal predictability studies). University partners with Earth System modelling activities
include Lund University (ecosystems, vegetation, land-use change, biogenic aerosols),
Stockholm University (ocean modelling, sulphate, soot and aerosol modelling and
observations, atmospheric boundary layer modelling and observations and atmospheric
chemistry), the University of Gothenburg (terrestrial biospheric process modelling and
observations, ocean modelling, process evaluation of biogeochemical cycling and statistical
downscaling) and Uppsala University (waves and marine boundary layer, high resolution
modelling). The Swedish Agricultural University also has relevant activities on soil, carbon
and forest system modelling.
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