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About CliC

Tinayrebreen Photo: ©Ann Kristin Balto, Norwegian Polar Institute, August 2008 CliC aims to improve understanding of the cryosphere and its interactions with the global climate system, and to enhance the ability to use parts of the cryosphere for detection of climate change.

The "Climate and Cryosphere" project, encourages and promotes research into the cryosphere and its interactions as part of the global climate system. It seeks to focus attention on the most important issues, encourage communication between researchers with common interests in cryospheric and climate science, promote international co-operation, and highlight the importance of this field of science to policy makers, funding agencies, and the general public. CliC also publishes significant findings regarding the role of the cryosphere in climate, and recommends directions for future study. CliC was established as a core project of theWorld Climate Research Programme in 2003.

The CliC Scientific Steering Group (SSG) is composed of world renowned researchers and has the overall responsibility for planning and guiding the CliC project. Read more about the CliC SSG.

The International Project Office is hosted at the Norwegian Polar Institute in Tromsø, Norway with funding from the Norwegian Ministry of Environment and the Research Council of Norway.

CliC is very fortunate to have a large number of leading cryosphere researchers working with us through regional and national programs, working groups, expert panels, and more.

WCRP CliC Project Action Plan 2016-2020
Melting Ice - Global Consequences Grand Challenge: Initial Implementation Plan: 2015
Cryosphere Grand Challenge White Paper: 2012
CliC Implementation Plan: 2007
CliC Science and Coordination Plan: 2001
ACSYS Implementation Plan: 1994


Goals of CliC

Austfonna ice cap in Svalbard Photo: ©Andrea Taurisano, Austfonna 2007 The principal goal of CliC is to:

Assess and quantify the impacts of climatic variability and change on components of the cryosphere and their consequences for the climate system, and determine the stability of the global cryosphere.

In order to achieve this goal CliC has the supporting objectives to:

  • Enhance the observation and monitoring of the cryosphere and the climate of cold regions in support of process studies, model evaluation, and change detection and other applications.
  • Improve understanding of the physical processes and feedbacks through which the cryosphere interacts within the climate system.
  • Improve the representation of cryospheric processes in models to reduce uncertainties in simulations of climate and predictions of climate variability and change.
  • Facilitate and support scientific assessments of changes in the cryosphere and their impacts, in particular to the IPCC 5th Assessment Report.


To attain these goals, CliC seeks to develop and coordinate national and international activities aimed at increasing the understanding of four main scientific themes:

  • Interactions between the atmosphere and snow and ice on the land surface.
  • Interactions between glaciers and ice sheets and sea level.
  • Interactions between sea ice, oceans, and the atmosphere.
  • Interactions of the cryosphere with the atmosphere and oceans on a global scale.


CliC encourages the use of observations, process studies and numerical modelling within each of the above topic areas. In addition, CliC promotes the establishment of new cryospheric monitoring programmes.


CliC's Role in WCRP and the Cryosphere Community

Sea-ice photographed from the air, with large square cracks. Lance ICE cruise Photo: ©Angelika Renner, Norwegian Polar Institute, Svalbard 2011 The key element of CliC is that it will provide a globally integrated approach to the study of the role of the cryosphere in the climate system. The science and coordination plan to be developed will look at the requirements for initiating studies of cryospheric elements in which there are perceived gaps in present programmes that impact on global change research including sea level rise. It will also look at requirements for enhancing links between existing global and regional cryospheric studies and lay out a programme for ensuring accurate and appropriate treatments of cryospheric processes and interactions of the cryosphere with atmosphere, oceans and land surface in climate models and for assembling the global and regional cryospheric data sets necessary for driving and validating climate models and for diagnostic studies of the role of cryosphere in climate. Important from the coordination point of view is to provide suggestions for mechanisms for interactions with other WCRP projects, in particular GEWEX and CLIVAR, and with other cryospheric projects that could contribute to WCRP research, including identification of suitable links and mechanisms for collaboration. In summary, CliC aims to have the following primary missions and activities:

  • Vessels and iceberg in close neighborhood in the lulissat harbor Photo: © Anders Skov Hansen/ARC-PIC.COM Coordinates the cryospheric elements of existing projects of the WCRP (especially CliC, GEWEX, CLIVAR) with the aim of identifying gaps in WCRP global cryospheric research within, and at the interfaces between, these projects.
  • Coordinates, sponsors, and encourages cryosphere projects conducted under other organisations (e.g., SCAR in the southern hemisphere, IASC in the northern hemisphere) to ensure appropriate broadening of these activities and that these serve WCRP needs related to the study of cryosphere and climate.
  • Acts as the "friendly broker" between programmes and projects (both internal and external to WCRP) that are conducted in the cryosphere with some common aims, such as CLIVAR-CliC, CliC-GEWEX, ASPeCT-WCRP and MAGICS-WCRP (among others).
  • Establishes projects in the study of the role of the cryosphere in climate that cover identified gaps; these projects may involve joint sponsorship by the appropriate governmental and non-governmental bodies.


History of CliC

Scientist from Ohio State University awaiting pick-up after installing a GNET GPS station on Timmiariit Island, SE Greenland, as part of the research efforts to estimate ice mass changes in the Greenland Ice Sheet. Photo: ©Dana Caccamise, Ohio State UniversityAt their annual meeting, held in Cape Town, South Africa from 16-20 March 1998, the Joint Scientific Committee (JSC) for the World Climate Research Programme (WCRP) reviewed the issue of the organisation of research into the Climate and Cryosphere in the WCRP. Key to this review was a paper from the ACSYS Scientific Steering Group (SSG) identifying gaps in our knowledge of some cryospheric processes in the climate system and summarising the various options for the organisation of cryospheric studies within WCRP. This paper was developed by a subgroup at the sixth ACSYS SSG meeting (November 1997), chaired by Professor Roger Barry. As a result of their review, the JSC XIX endorsed the idea of a broader programme on Climate and Cryosphere (CliC) in the WCRP (WMO/TD-No. 929, 1998). As a first step, a Task Group was established to develop a science and coordination plan for CliC for presentation at the twenty-first session of the JSC in March 2000, when the decision will be made on whether to initiate CliC as a full WCRP project. More detail on the background to this can be found in an article by Hartmut Grassl and Victor Savtchenko "Cryosphere and Climate: organisation of the WCRP contribution" in WCRP Newsletter No. 2 and an article by Howard Cattle and Roger Barry "Cryosphere and Climate, The ACSYS Statement" in WCRP Newsletter No. 3.

- Howard Cattle -- Past Chairman, ACSYS/CliC SSG

On thin ice, taking water samples for the long-term monitoring of sea-ice in Kings Bay Photo: ©Sebastian Gerland, Norwegian Polar Institute, Svalbard 2006

Background Statement Introduction

An international symposium on 'Antarctica and Global Change: Interactions and Impacts' (1997, Hobart, Australia) proposed that "a WCRP sub-programme on the Antarctic should be formed analogous to the Arctic Climate System Study." The conference on WCRP: Achievements, Benefits and Challenges (1997) further proposed that WCRP should establish an activity to co-ordinate global cryospheric research.

Below is a shortened version of a statement/proposal of the 6th ACSYS Scientific Steering Group (SSG) session in 1997 which was requested to utilize the deliberations and results of the second ACSYS Science Conference on 'Polar Processes and Global Climate' to develop "a comprehensive statement on the overall status of studies of cold climate processes and the role of the cryosphere in climate, together with a proposal for the overall organization/integration of climatically important cryospheric aspects".

A. The need for an integrated cryospheric component of global climate research

The term "cryosphere" collectively describes elements of the Earth system containing water in its frozen state. This includes the ice sheets, ice shelves, ice caps and glaciers, sea ice, seasonal snow cover, lake and river ice, and seasonally frozen ground and permafrost.

Many cryospheric elements and processes are already the subject of international co-operative research. But, with the notable exception of the Arctic Climate System Study (ACSYS), these are generally outside the framework of the World Climate Research Programme. Many of the projects are also regional, and links into the global climate research effort are less comprehensive than is necessary. The large WCRP projects CLIVAR and GEWEX both have cryospheric components, but these are largely treated as subservient to the broader aims. If integrated within the WCRP framework, several of the externally sponsored programmes could provide additional support to the GEWEX and CLIVAR objectives.

Integration of existing cryospheric projects within a global research structure, together with new efforts addressing current gaps, is required in order to enhance links between regional and global climatic components studies; promote appropriate treatment of cryospheric processes in climate models, and assemble the global gridded data sets necessary for driving and validating climate models. This is needed not only at a global scale, but also at the regional level, and between different elements of the cryosphere. For example, ocean stratification from the melt of ice sheets, icebergs and glaciers influences both ocean circulation and sea-ice distribution.

The principal scientific questions relating to the cryosphere concern global sea level; the energy and water cycle in regions with sea ice, land ice and frozen ground; the roles of polar fresh water for the ocean thermohaline circulation, and the interactions of snow cover, sea ice, and seasonally frozen ground in the climate system In addition, the impacts of global change on elements of the cryosphere may have significant social and economic ramifications (Fitzharris, 1996).

Present knowledge of the role of the cryosphere in the climate system does not discount the possibility of a number of 'surprise' responses. These include: (i) increases in both Antarctic accumulation and sea ice (through ice formation from snow) with increased temperature; (ii) reduction in Antarctic bottom water formation due to increased melt of ice shelves (although strictly a regional effect, the collapse of the Larsen Ice Shelf injected additional fresh water into the ocean (in less than one year) equivalent to about a half-year sea-ice transport through the Fram Strait); (iii) melt of permafrost and release of methane; and (vi) shut-down of the deep water formation in the high latitudes of the North Atlantic.

B. Current status of research into the cryosphere and climate

The cryosphere acts as both an integrator and indicator of climate variability and change. Snow and ice are not simply polar phenomena, but are global in occurrence. In winter, snow covers up to 60% of the Northern Hemisphere land area, about 80% of global fresh water is contained in ice sheets and glaciers, and permanently frozen ground underlies 25% of the global land surface. Current or planned activities of the WCRP address certain cryospheric issues, either on a regional basis (ACSYS, including the Sea-Ice Model Intercomparison Project, the Antarctic Sea-Ice Thickness Project and the International Programme for Antarctic Buoys), or on a project basis (BALTEX, GCIP, MAGS and GAME of GEWEX continental scale experiments). Some other aspects of the cryosphere are addressed by others. For example, the glacier initiative of International Arctic Science Committee Mass balance of Arctic Glaciers and Ice Sheets in relation to Climate and Sea level changes (MAGICS); the Scientific Committee on Antarctic Research Global Change and the Antarctic (GLOCHANT) Programme; the Antarctic Sea-Ice Processes and Climate Project (ASPeCt) - an element of GLOCHANT; Scientific Committee on Oceanic Research iAnZone projects studying the role of Antarctic waters and processes in the global ocean and climate system; the International Permafrost Association activities on permafrost and global change, and mountain permafrost.

However, there is NO global programme focusing on the role of the cryosphere in the global climate system. There are in fact serious gaps in the observations, process studies and modelling of cryospheric elements important for climate research, the study of cryosphere-climate interactions, their variability, change and associated impacts. Observational gaps are documented in the report of the Meeting of Experts on Cryosphere and Climate (WCRP, 1998: Tables 2 and 3). Cold climate processes relevant to key climate questions are often poorly known. For example, although several ice mass studies are contributing to the assessment of sea level change, the task of determining the contributions of Greenland and Antarctica - where even the sign of changes is uncertain - suggests that WCRP leadership could facilitate progress in both science and funding arenas. Cryospheric processes and phenomena are often poorly represented in climate models; ground ice, fresh water ice, glaciers, ice sheets and shelves are either not treated or are not fully interactive in GCMs. Snow cover and sea ice may be prescribed or interactive in atmospheric GCMs, while sea ice is interactive in coupled ice/ocean/atmosphere models. The accuracy of representation of cryospheric processes in GCMs, RCMs and process models requires validation by co-operation between modellers and cryospheric experts. To improve observing and modelling of the role of the cryosphere in global climate, a coordinated WCRP effort to address the gaps in current programmes needs to be implemented.

C. The cryosphere and its impacts

Snow cover is a major component of water storage on the seasonal timescale and changes in its extent, depth and water equivalent will have a major impact on alpine and continental water resources, floods and droughts and their relation to hydropower production, flood forecasting, agriculture production or input to fresh water flow into the world ocean affecting ocean circulation. Sea ice has a major effect on thermohaline circulation of the world ocean; changes in extent of sea ice could cause changes in the world's ocean circulation. Glaciers and ice caps may account for 1/3-1/2 of the observed 20th century sea-level rise; future loss of alpine glaciers will continue to contribute to sea-level rise and will have significant negative impacts on local water supply, hydropower production and tourism. Ice sheets have direct impact on sea-level rise and coastal flooding, through iceberg production they affect marine navigation; yet we are still unsure of the sign and magnitude of the mass balance of Antarctica. Ice shelves determine the discharge of meltwater and icebergs into the Southern Ocean. Frozen ground/permafrost, and the related seasonal cycle have a direct effect on the hydrological cycle; thawing of the permafrost will disrupt man's engineered works and will affect surface heat and moisture balances, run-off, and chemical fluxes to the atmosphere and hydrosphere, especially the potential release of CO2 and methane.

D. Potential organizational structures and references

The following four options for the treatment of the cryosphere within WCRP were considered by the ACSYS SSG:

  1. Rely on existing WCRP projects to treat the relevant aspects of cryospheric/cold regions research;
  2. Expand ACSYS to address the seasonal sea-ice zone of the Antarctic, the Antarctica ice sheet and shelves under an AACSYS (Arctic and Antarctic Climate Systems Study);
  3. Implement a "Cold Regions - Climate Interactions" (CReCI) project as a framework comprising ACSYS and projects external to WCRP which have asked for WCRP recognition (such as MAGICS and ASPeCt);
  4. Establish a "Cryosphere and Climate" (C&C) project which specifically focuses on the cryospheric components and their interactions with complementary parts of the climate system.

Because of the substantial gaps in existing WCRP and other activities identified above, and the difficulties of co-ordinating cryospheric research across different WCRP projects, the ACSYS SSG-VI considered that option 1 should not be adopted. The expansion of ACSYS option 2 to include Antarctic topics not so far addressed by the WCRP - in an AACSYS - suffers from the disadvantage of having no clear boundaries with CLIVAR and GEWEX. Furthermore, an AACSYS would remain as the single regional project within WCRP. The preceding objections also pertain to option 3 for a CReCI. Moreover, the term "cold regions" has several differing interpretations.

In forming its view of option 4, the ACSYS SSG recognised that not all elements of the cryosphere are coupled enough to provide a strongly interacting project in all its aspects. However, given the strong need for WCRP leadership in global cryospheric research, the ACSYS SSG recommends adoption by JSC-XIX of option 4. The "Cryosphere and Climate" project approach complements the existing WCRP projects: SPARC for the stratosphere, GEWEX for the troposphere and land surface, CLIVAR for the ocean and the coupled ocean-atmosphere climate system; all WCRP projects then will have a global view. The SSG also recommends that a 'Cryosphere and Climate' project be implemented under WCRP without delay and that, following the conclusion of ACSYS (AD 2003, currently), the project should subsume any continuing ACSYS activities for the cryosphere and its interactions with other components of the climate system. Other ACSYS activities for the oceans, atmosphere, hydrosphere relevant to WCRP should then be transferred to CLIVAR or GEWEX, as appropriate.

The success of such a C&C project regardless of its organizational structure, depends directly on the strength of its communication and linkages within the C&C itself across the various sub-elements, with other relevant WCRP projects, and with external programmes having a cryospheric focus. A considerable number of linkages can already be identified. At present, these primarily involve formal liaison through panel/steering group membership and informal co-operative arrangements. To ensure the effectiveness of these linkages, given the expanded nature of the proposed new C&C structure, the ACSYS SSG recommends that formal links through liaison members be enacted as broadly as practical, supplemented by regular workshops across the C&C project, and less frequent joint workshops/meetings with other relevant programmes/organizations and the C&C project . The ACSYS SSG also proposes regular and timely dissemination of key C&C project findings and recommendations through regular brief reports. Finally, it is suggested that the ACSYS SSG be developed to instigate the management of the new C&C project. In particular it could be evolved to encompass the various C&C project element chairs in order to ensure that intra-project communication occur in the most efficient and effective manner.


Fitzharris, B.B.,(Ed.), 1996: The cryosphere: changes and their impacts. In: R.T. Watson et al., Climate Change, 1995. Impacts, Adaptations and Mitigations of Climate Change: Scientific-Technical Analyses, Cambridge Univ. Press, pp. 224-265.

WCRP, 1998: Proceedings of a meeting of experts on cryosphere and climate (Cambridge, UK, 3-5 February 1997), R.G. Barry (Ed.), WCRP-102, WMO/TD No. 867.

WMO/TD-No. 929, 1998: Annual review of the World Climate Research Programme and report of nineteenth session of the Joint Scientific Committee (Cape Town, S. Africa, 16-20 March 1998).