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CliC News

Here's what has been happening lately in CliC. Let us know if you have things to share.

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Sea-Ice Model Intercomparison Project (SIMIP) protocol available online

-Contributed by Dirk Notz

simip seaice2The Sea-Ice Model Intercomparison Project (SIMIP) of the 6th version of the Coupled Model Intercomparison Project (CMIP6) aims at a better understanding of the role of sea ice for the Earth's climate system. In particular, we want establish the sensitivity of sea ice to changes in the external forcing, understand differences between individual model simluations, and examine how predictable the future evolution of sea ice is on time scales ranging from days to centuries.

To reach these aims, SIMIP has compiled a new protocol for the output of sea-ice related variables from coupled model simulations. This protocol allows any researcher to analyse the three main budgets that govern the evolution of sea ice, namely conservation of heat, the momentum budget, and salt/tracer conservation. Based on an analysis of these budgets, one can identify the main reason for a different response of sea ice both within a set of models and between individual models and reality. Thus, it becomes possible to understand model biases and to improve our simulations of future sea-ice evolution. In particular, we will be able to quantify how much of the current spread of model simulations of future Arctic sea-ice evolution can possibly still be improved by improving the model, versus how much of this spread is an inherent uncertainty of the dynamic climate system controlled by internal variability.

Supported by CliC, the SIMIP Steering Committee has over the past few months had an open consulting process with sea-ice researchers from various backgrounds to settle on a protocol that forms the best possible compromise between the complete coverage of sea-ice related model output and minimizing storage requirements. This protocol is now finalised and currently under consideration by the CMIP6 panel. In particular, the panel will establish how much of this protocol will be included into the recommended set of variables that must be stored for the CMIP6 DECK experiments. Once this is done, we will eagerly await the first results from CMIP6 to start analysing sea-ice evolution in the simulations at a more detailed level than has ever been possible before.

The SIMIP protocol is available for download and further comments at: http://www.climate-cryosphere.org/activities/targeted/simip

Report Available: Permafrost Carbon Network Leads Meeting 2015

1-PCN 2015The Permafrost Carbon Network (www.permafrostcarbon.org) held another successful workshop for synthesis leads and co-leads in Flagstaff, AZ, USA (May 11-12, 2015). The objectives of this workshop were to bring together leading scientists of the Permafrost Carbon Network to discuss and plan new synthesis products. One particular focus of this meeting was to advance model development by exploring benchmarking tools that can be provided by field and lab based scientists along with finalized model output from the Permafrost Carbon Model Intercomparison Project that estimates the permafrost carbon climate feedback for this century and beyond. In advance of the workshop, participants prepared scoping papers that contained details about the new syntheses. The majority of the workshop was used to discuss and refine these newly proposed synthesis activities as a group and to outline best strategies for ways forward. The follow-up activities of this workshop are outlined in individual scoping documents, which are shared with members of the Permafrost Carbon Network through our website. Upcoming, we will have short presentations during our 5th Annual Meeting of the Permafrost Carbon Network at AGU in December of 2015, where brief updates about the progress of individual synthesis activities will be given to the larger community of scientists. The workshop in Flagstaff, AZ was sponsored by the National Science Foundation, Climate and Cryosphere (CliC) and contributions from individual participants.

Read the Report

Presentations Available:

T Schuur: Permafrost Carbon Network Update
D McGuire: Model-Integration Working Group Products of Synthesis
C Koven: The Pan Incubation-Panarctic Thermal Scaling Approach

CliC Director on Arctic Panel at IOC-UNESCO

2015-ICO-Baeseman_Photo-from-GOOSAn Ocean Science Day was organized by the Intergovernmental Oceanographic Commission (IOC-UNESCO) on 17 June 2015 to share recent developments in ocean science with representatives of its 147 Member States, networks and partners. The overall objective was to improve decision makers’ understanding and awareness of current challenges and emerging issues, through lectures and panel discussions with eminent experts. Presentations and debates focused on the linkages between ocean health and human wellbeing, the potential of the latest advancements in monitoring technology, current scientific challenges in the Arctic and the legacy of the International India Ocean Expedition.

CliC’s Director, Jenny Baeseman, joined Volker Rachold from IASC and Erik Bunch of EuroGOOS to discuss “Scientific Challenges in the Arctic” chaired by Vladimir Ryabinin of IOC. The rapid transformations occurring in the Arctic are affecting the entire Earth system, including its climate and weather extremes, through increased temperatures and the continuing loss of ice, glaciers, snow and permafrost. These rapid changes are challenging our ability to provide decision-makers with the necessary knowledge on the consequences. Sustained observations and improved understanding of local, regional and global processes are required in order to anticipate changes in the Arctic. Download Jenny’s presentation here. Read more about the Ocean Science Day at: http://www.unesco.org/new/en/natural-sciences/ioc-oceans/single-view-oceans/news/current_challenges_and_emerging_issues_of_ocean_science/#.VYpcPufk5NE

Seeking Comments on Southern Ocean Satellite Needs Community Report

so sat req withscarIn order to address growing disparities in Polar remote sensing, and in particular to articulate the satellite needs specific to the Southern Ocean, last year SOOS (The Southern Ocean Observing System) and CliC (Climate and the Cryosphere Project) coordinated a community survey to canvas uses of remote sensing and define limitations and recommendations for improvement of Southern Ocean remote sensing.

These survey responses have been brought together into a summary report, which we are now circulating again around the entire Southern Ocean community (both operational and research). Sections of the report include sea ice variables, atmospheric parameters, SST, SSH, SSS, terrestrial cryospheric connections, marine microbes / ocean color, marine biology, surface winds, and more.

We encourage all interested members of the Southern Ocean community to review relevant sections and submit any comments edits by the end of July. We want you, the community, to ensure that the content is complete and that the report’s recommendations are detailed, innovative, and accurate. The aim is that this review will represent the Southern Ocean community’s satellite data needs for the coming decade. It is designed to stand as an important strategy paper that provides the rationale and information required for future strategic planning and investment.

We ask that you use a Google Doc to provide feedback, so that it can be a more collaborative effort (https://docs.google.com/document/d/1oCXwPU8ykGYv9h4W0i5lzIqWpcpF0m4JX6MRP6BjEJs/edit?usp=sharing; there is a linked table of contents to make it easier to access your section of interest). However, if you are unable to access the Doc for some reason, please contact us (; subj: Southern Ocean Satellite Report) and we will be able to provide you with a PDF or Word version.

Thank you for taking the time to contribute to this valuable community effort!
Allen Pope, NSIDC/UW  -  Penelope Wagner, MetNo  -  Rob Johnson, UTAS  -  Jenny Baeseman, CliC  -  Louise Newman, SOOS

Ice Sheet Model Intercomparison for CMIP6 (ISMIP6) endorsed by CMIP6

-Contributed by Sophie Nowicki

ismip6The Ice Sheet Model Intercomparison for CMIP6 (ISMIP6) is a CliC targeted activity established in Autumn 2014 with the aim of integrating modelling of the ice sheets into the next phase of the international Coupled Modelling Intercomparison Project (CMIP6) so that projections of mass budget (hence of sea level) are more readily available for the next IPCC. Recently, we received the fantastic news that ISMIP6 has been formally endorsed by CMIP. This will greatly aid the collaboration between the ice-sheet community and those working on other aspects of the coupled climate system. In particular, it will ensure the coordinated provision of climate forcing data for the ice sheets, and focus attention on the quality of climate simulation over (and around) the ice sheets.

Over the year, ISMIP6 has been making steady progress. Important developments include an initial workshop held at NASA Goddard Space Flight Center 16-18th July 2014 (supported by CliC) at which the ISMIP6 concept was discussed with the ice sheet and climate modelling communities. An important outcome was the recognition that two strands of modelling would be necessary: fully coupled in which the ice sheet model sits within a larger climate model and is fully coupled to it; and stand-alone in which ice sheet models are forced by the output of climate models (but are not explicitly coupled to them). The former will focus on Greenland, while the latter will involve both ice sheets. It was felt that fully-coupled modelling is not currently feasible for Antarctica because of uncertainties in both the oceanic forcing and ice-dynamic response of the ice sheet.

A Steering Committee has since been formed and has been working towards a first intercomparison exercise with the aim of developing community engagement from at an early stage. The committee comprises: co-chairs Sophie Nowicki, Eric Larour and Tony Payne with Bill Lipscomb, Heiko Goelzer, Ayako Abe-Ouchi, Andrew Shepherd, Helene Seroussi and Jonathan Gregory. Initial ideas for this exercise were discussed at the EGU in a splinter meeting organised by Heiko and Tamsin Edwards. The final experimental design will be agreed at the forthcoming International Glaciological Society symposium in Cambridge (August 16th-21st) with results presented at the Fall AGU. The theme for this intercomparison will be the methods of model initialisation and their effect on projections.

See more information on the upcoming ISMIP6 meeting at the IGS Symposium in Cambridge in Augsut 2015 here.

Call for Participation: Earth System Model-Snow Model Intercomparison Project (ESM-SnowMIP)

Snow-Contributed by Gerhard Krinner and Chris Derksen

The Earth System Model-Snow Model Intercomparison Project (ESM-SnowMIP) is a new initiative that aims at evaluating and improving the representation of snow primarily (but not exclusively) in Earth System Models and at better quantifying snow-related climate feedbacks. It consists of a suite of coordinated experiments at the site level and on the global scale, plus numerical experiments in the Earth System Model framework.

ESM-SnowMIP is part of the WCRP Grand Challenge "Cryosphere in a Changing Climate" and is designed as a follow-up project to previous SnowMIP initiatives and complements, by a specific focus on snow, the Land Surface, Snow, and Soil moisture MIP (LS3MIP) subproject of CMIP6 that is designed to evaluate land surface modules of Earth System Models and to quantify land-related feedbacks. Compared to previous SnowMIP editions, a new and enlarged set of sites for model evaluation and testing is used.

We solicit participation in ESM-SnowMIP by:
-Earth System Modeling groups, particularly those that participate to the LS3MIP subproject of CMIP6;
-Snow and general land surface modelers (both site- and large scale).

At this stage, our aim is to obtain expressions of interest from the scientific community and receive feedback to the initial ESM-SnowMIP simulation protocol available here.

We anticipate that, besides progress due to coordinated model testing and benchmarking, the common participation by Earth System Modeling groups and specialized snow scientists will generate scientific momentum that will allow substantial knowledge transfer to the Earth System Modeling community, and thus allow for significant improvement of the representation of snow in global climate models.

The general timeline of ESM-SnowMIP aims to initiate site- and global-scale offline simulations in 2016, while coupled model simulations (complementing numerical experiments carried out in the LS3MIP framework) will start in 2018 after CMIP6.

The ESM-SnowMIP steering committee members are: Gerhard Krinner, Chris Derksen, Richard Essery, Stefan Hagemann, Alex Hall, Andrew Slater, Matthew Sturm and Helmut Rott. Please send your expressions of interest to Gerhard Krinner and Chris Derksen.

Report Available: Constraining Greenland Ice Sheet Surface Mass Balance Model Validation Workshop

GrISSMB SheffieldMtg2015 GroupPhoto3Greenland Ice Sheet International Workshop Group Photo, May 2015, Sheffield, UK

-Contributed by Ed Hanna and Amy Jowett

Seventeen glaciologists and climatologists met in Sheffield for a two-day international research workshop on 19/20 May on how we can best improve the representation of Greenland Ice Sheet surface mass balance (SMB) in computer models of climate change. This is a challenging but exciting prospect as we attempt to model SMB, which equals net snowfall minus snow/ice meltwater losses, occurring over an ice mass with the combined surface area of France, Germany Italy and Spain.

The event was sponsored by the Climate and Cryosphere project of the World Climate Research Programme (WCRP CliC) and by the Ice Sheet Mass Balance and Sea Level working group (ISMASS) that is co-sponsored by CliC. Participating scientists came from several different countries including the the UK, Netherlands, Belgium, Denmark, USA - including representation from NASA - and Chile. The delegates included representation of all the SMB models used in the recent Intergovernmental Panel on Climate Change's (IPCC) Fifth Assessment Report (Working Group I, Chapter 13 on Sea Level Change).

There is still very significant disagreement in the amounts of snowfall and meltwater runoff simulated by the different SMB models, and so we aim to reconcile model differences through a more thorough and detailed comparison of output from the different models than has previously been undertaken. The workshop also addressed the important question of where there are gaps in information from weather stations and ice-core data which are crucial for validating SMB models over Greenland.

It is anticipated that the SMB model intercomparison project and improvements promoted by this workshop will result not only in a dedicated peer-reviewed journal publication significantly advancing the science within the next 6-12 months but will also feed directly into improving estimates of the contribution of the Greenland Ice Sheet to global sea-level rise, to be reported in the next IPCC report around 2020. Apart from one and a half days of talks and discussion held in the Ron Johnston Research Room, the workshop featured a brief excursion to our Bradfield Environmental Laboratory on the second afternoon (when the showers held off!), as well as a workshop dinner in a traditional Sheffield pub. A great time was had by all.

Download the Draft ACTION PLAN arising from GrIS SMB modelling/model validation CliC/ISMASS Sheffield workshop here.

The full report of the workshop is available here.

Read more about the workshop here.


Utility and Quality of Reanalyses in the Polar Regions Session at Fall AGU 2015

Session ID: 8005AGU 2015
Session Title: Utility and quality of reanalyses in the polar regions
Conveners: David Bromwich and James Renwick

Reanalyses are key tools for investigating climate variability and change in the data sparse polar regions. Originally focused on the atmosphere only, some reanalyses now focus solely on the ocean or the land surface, while coupled atmosphere-ocean reanalyses are starting to be produced. There are many challenges to producing reliable reanalyses in the polar regions. Contributions are solicited on the following: intercomparison of reanalyses, both global and regional; polar-specific challenges regarding observations, data assimilation, model physics, oceanic boundary conditions, especially sea ice; reanalysis for the Southern Ocean and Antarctica before the start of the satellite era; ensemble approaches for background error, reanalysis uncertainty, and compositing reanalyses; and reliability of trends and climatologies.

Please click here for more information on the abstract submission process.  Abstract submission deadline: August 5, 2015
Further details, including invited speakers, date, and time, will be announced in due course. More information on the session is available here.

Raising the visibility of the Cryosphere in CMIP6

CMIP6 logo-Contributed by Greg Flato

Perhaps one of the most widely-cited activities of the WCRP is the series of Coupled Model Intercomparison Projects organized by the Working Group on Coupled Modelling (WGCM). The 5th version (CMIP5) was a very ambitious effort that provided coordinated global climate model simulations including, idealized, preindustrial, transient historical, decadal predictions, and longer-term future projections under different forcing scenarios. Results from these simulations served as the basis for much of the material in Chapters 9 through 14 of the Working Group 1 contribution to the IPCC 5th Assessment Report (AR5), as well as the new Atlas of Global and Regional Climate Projections (Annex 1 of the AR5). CMIP5 model output continues to be used extensively and can be accessed via the CMIP5 Data Portal based upon the ‘Earth System Grid Federation’. At the time of writing, there were 785 publications that cited CMIP5 model output.
The 6th version of this (CMIP6) is currently being planned and it is expected to be a major contribution to the upcoming IPCC Assessment Report. A thorough description of CMIP6 is available here, and involves a somewhat different approach than was the case for earlier versions of CMIP. In particular, the planning of various components of CMIP6 has been left to the scientific community to ‘self-organize’ to a large extent. CliC has been active in supporting this to ensure that the Cryosphere is well represented. In particular, we have organized workshops to facilitate the preparation of three model intercomparison activities specifically targeting the Cryosphere. These are:
-ESMSnowMIP - a snow model intercomparison that is part of a broader land surface model intercomparison activity jointly organized with GEWEX
-ISMIP6 - an intercomparison of large-scale ice sheet models
-SIMIP - a diagnostic intercomparison aimed at evaluating the performance of the sea-ice component of CMIP6 global models.

These activities are described in more detail below, and each has an active group of international scientists leading the planning and coordination. The end result will undoubtedly contribute significantly to our understanding of the ability of global Earth System Models to simulate components of the cryosphere and their interactions with other components of the climate system. These intercomparisons also provide valuable information and guidance to model developers by revealing model strengths and weaknesses (through direct comparison to observations), and providing insight into the causes. Furthermore, by assuring that a comprehensive suite of relevant model output is archived, the broader scientific community will be able to probe model results, confront the model results with new observations and process understanding, and provide quantitative projections of future cryosphere changes that support impact assessment and adaptation planning.

One other CliC targeted activity that is not formally a part of CMIP6, but which will be closely aligned, is the Glacier Model Intercomparison Project. This effort will be closely aligned with ISMIP6 and evaluate models of global glacier mass balance which typically make use of climate projections from global Earth System models. GlacierMIP will complement the other CMIP6 cryosphere activities and will certainly provide information relevant to sea-level rise and water availability projections.