ISMIP Meeting
Ice Sheet Model Intercomparison Project Planning Workshop for ISMIP7
Figure 1. The workshop venue on the shores of the Potomac River in Virginia provided a serene setting. (Photo credit: Matt Hoffman)
The Ice Sheet Model Intercomparison Project held the kickoff meeting for its next phase, ISMIP7, on June 10-14, 2024, in a hybrid format hosted at the Algonkian Regional Park in Sterling, Virginia (Fig. 1). ISMIP7 is an official community activity of the Coupled Model Intercomparison Project (CMIP) sponsored by the United Nations Intergovernmental Panel on Climate Change (IPCC) that will define a set of standard ice-sheet model experiments for projecting the future of the Antarctic and Greenland Ice Sheets. These simulations will be conducted by modeling groups from around the world in the coming three years, and the resulting multimodel ensemble will be a critical element informing sea-level projections in the IPCC’s seventh climate change assessment report planned for 2029. This activity follows on the successful ISMIP6 intercomparisons, in which 14 ice-sheet modeling groups contributed for Greenland and 13 for Antarctica, culminating with a series of papers, including a special issue of The Cryosphere in 2020.
The aim of the ISMIP7 kickoff workshop was to define the goals of ISMIP7 and begin formulating an experimental protocol through the coordination of 6 focus groups. The workshop included 41 in-person and 49 virtual attendees, including members of the ISMIP Steering Committee and Focus Groups, ice-sheet modelers, and downstream users of ISMIP products (Fig. 2). The workshop began with an overview of the previous ISMIP6 effort and a series of talks from users of ISMIP results for sea-level projections and coastal practitioners. This helped set the stage for what is needed to make the intercomparison most useful and impactful. A major theme of these discussions was the need to quantify uncertainties in ice-sheet projections and to represent the full range of uncertainties inherent in model projections.
Figure 2. The workshop employed a hybrid format with 100 attendees.
The next phase of the workshop provided an overview of the six focus groups covering ice sheet surface forcing, Greenland and Antarctic ocean forcing, ice-shelf fracture, glacial isostatic adjustment, and curating ice-sheet observations. Discussion sessions facilitated coordination across focus groups and identified dependencies between them in creating the ice-sheet modeling protocol. Subsequently, two full days were devoted to protocol development within each focus group, with repeated opportunities for further coordination between them.
The outcome of the workshop was to lay the groundwork for finalizing experimental protocols in the next year, with a timeline of having ice-sheet modelers begin their simulations in late 2025 to support CMIP7 publication deadlines in 2027. This will be an iterative process, with follow-on community ISMIP7 meetings scheduled at the International Glaciological Society symposium in August in Newcastle, UK, and the American Geophysical Union Annual Meeting in December in Washington, DC, where input will be solicited from the larger glaciology, climate, and sea-level communities.
The DOE Earth system modeling community was strongly represented at the workshop, with attendance by Xylar Asay-Davis (Los Alamos National Laboratory; ISMIP7 Steering Committee member), Matthew Hoffman (Los Alamos National Laboratory; ISMIP7 Sea Level Focus Group co-lead), Jeremy Bassis (University of Michigan; ISMIP7 Ice-Shelf Fracture Focus Group member), and Irena Vaňková (Los Alamos National Laboratory; ISMIP7 Antarctic Ocean Focus Group member). DOE investment in ice-sheet modeling, polar oceanography, and sea-level science has enabled a position of leadership in the ISMIP effort. In turn, the E3SM ecosystem benefits from increased visibility, an opportunity to contribute unique knowledge and capabilities to the international effort, and the agility to target model development and simulation resources to effectively participate without sacrificing core project foci. As an example of this synergy, DOE workshop participants learned of recommended ocean climatology reanalysis products that can be used by the E3SM Polar Processes Team for validation of ocean conditions around Greenland. Another example is coordination between ISMIP7 and the Framework for Antarctic System Science in E3SM (FAnSSIE) SciDAC project on validation datasets for glacier calving, which will reduce the burden for both efforts.
In many ways, the June workshop led to more questions about the protocol for ISMIP7 than it resolved, but this is the first step in the complex but essential process for building a consensus community activity. The workshop was a tremendously successful start to ISMIP7, and there was palpable excitement by the participants for the work to come. The ISMIP7 workshop was generously supported by the Heising-Simons Foundation.
Contact
- Matt Hoffman, Los Alamos National Laboratory
- Xylar Asay-Davis, Los Alamos National Laboratory
This article is a part of the E3SM “Floating Points” Newsletter, to read the full Newsletter check:
