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About CliC

Snow on sea ice

Alek Petty (alek.a.petty[@]nasa.gov)

The scientific questions that will be studied:
This theme will investigate snow on sea ice in CMIP6 models. As our knowledge of snow on sea ice in global climate models is a relatively new line of enquiry, we expect this theme to start with a basic intercomparison analysis. From here we hope to explore deeper questions, including:
- How sophisticated is the snow physics included in the CMIP6 models.
- Has the inclusion and sophistication of snow physics improved since CMIP5?
- Do the models that include a prognostic snow layer produce more accurate sea ice simulations?

The processes that will be investigated:
-For the models that include a prognostic snow layer, how does snow form and melt, and how is it redistributed in the different models? What is the snow mass balance?
- What are the major differences between the representation of snow on sea ice in Arctic and Antarctic simulations across the models.
-How much snow ice conversion is occurring in the models that include this process. How does this vary across the Arctic and Antarctic.
The type of analyses that will be conducted:
-The analysis will start from a pretty basic level of model intercomparison, as to our knowledge, no such assessment of snow on sea ice in GCMs has been produced to-date (likely due to the basic treatment of snow in GCMs).

Tinayrebreen Photo: ©Ann Kristin Balto, Norwegian Polar Institute, August 2008 The Climate and Cryosphere (CliC) project is one of the core projects of the World Climate Research Programme (WCRP), serving as the focal point for climate science related to the cryosphere, its variability and change, and interaction with the broader climate system. CliC is overseen by a Scientific Steering Group (SSG) responsible for overall direction and planning. The International CliC Project Office (ICPO -- hosted by the Norwegian Polar Institute serves as the administrative home for the project. The CliC science strategy is aimed at promoting and facilitating new collaborative research related to the cryosphere and climate, making links between cryospheric research and research in other disciplines, and communicating research results to policy and decision-makers and other non-scientific users. Cryospheric research coordinated by CliC covers the Arctic, Antarctic, high-elevation mountain areas, and broad regions that experience snow and permafrost. It further informs a range of stakeholders in the relevant socioeconomic domains and contributes to international efforts like the Global Framework for Climate Services (GFCS).

CliC research spans the entire diversity of the Earth’s cryosphere: marine cryosphere, terrestrial cryosphere, alpine cryosphere, and ice sheets. A balance between disciplinary specialization and multi-disciplinary collaboration allows integrating the outcomes of this research as input to assessments and predictions of the cryosphere and climate. The connection between cryospheric observations, process studies and modelling (regional and global) is an increasingly important focus for CliC.

A further influence on CliC science planning is the concept of Grand Challenges, initiated as a result of the WCRP first Open Science Conference (Denver, USA, 2011). The WCRP Grand Challenges are areas of high-priority research, where it is thought that focussing efforts of the science community, over a 5- to 10- year time frame, can result in significant progress on a science problem of societal importance. The role of permafrost thaw in the global carbon balance, the fate of the Arctic summer sea ice, and the contribution of cryosphere to global and regional sea-level rise are examples of such problems and they constitute the substance of the WCRP Grand Challenge, “Melting Ice - Global Consequences” for which CliC serves as a focal point. As such, CliC has the responsibility for planning and implementation of this Grand Challenge, which includes activities of the WCRP Polar Climate Predictability Initiative. CliC also contributes to one of the work packages of the Grand Challenge on Regional Sea Level Rise, specifically that related to the contribution of land ice to sea level.

WCRP CliC Project Action Plan 2017-2021
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

Overarching Research Needs

Austfonna ice cap in Svalbard Photo: ©Andrea Taurisano, Austfonna 200The Science Themes and specific research questions outlined below generally contribute to the following overarching research needs that have been identified in various planning meetings over the past few years.

They are:
1. Improved understanding and quantification of the role of the cryosphere in the global climate system, its variability and change.
2. Improved utilization of cryospheric observations as indicators of global and regional climate change.
3. Improved understanding of the physical, chemical and other processes that govern behaviour of the cryosphere, and the representation of these processes in Earth System Models.
4. Improved ability to make quantitative predictions and projections of the cryosphere in a changing climate.