Increasing Model Participation in GeoMIP

Request for Proposals (RFP) ID: RE-1003

For any questions, please review the Q&A board before submitting your question via this form. If you’d like to schedule a conversation about your proposal, please email at grants@reflective.org.

Key Dates

Funding Context and Objectives

Background

Climate change is accelerating—intensifying extreme weather, driving biodiversity loss, and threatening global food systems. Even with stronger efforts to decarbonize and remove carbon dioxide from the atmosphere, most climate models project that temperatures will exceed safe levels for decades. In response, stratospheric aerosol injection (SAI)—the introduction of aerosols into the stratosphere to reflect sunlight and cool the planet—has emerged as a proposed means of slowing near-term warming and potentially reducing the risks associated with climate tipping points. While early modeling suggests SAI could quickly lower global temperatures, significant uncertainties remain.

Since its beginnings around 15 years ago (Kravitz et al., 2011), the Geoengineering Model Intercomparison Project (GeoMIP) has been a vital coordinating framework for standardized SRM experiments (Visioni et al., 2023). Sitting under the broader Coupled Model Intercomparison Project (CMIP), GeoMIP simulations allow for quantitative estimates of model uncertainty in the climate response to SRM, and underpin our assessments of the robust features of that response. The value of model intercomparison projects (MIPs) arises from the number and variety of models participating (e.g. Tebaldi & Knutti, 2007). However, at present, only a handful of earth system models have simulated the most recent set of GeoMIP experiments; four models have completed and shared G6-1.5K-SAI outputs at time of writing (Lee et al., 2026). With this limited number, statistics of the multi-model ensemble are sensitive to which models have participated, and it is difficult to confidently associate differences between model outputs with differences in model features.

Through this funding opportunity, we aim to increase the number and variety of earth system models (ESMs) participating in GeoMIP, in order to facilitate a more robust assessment of uncertainty in the climate response to SAI, and to support increased understanding of the physical processes which determine its impacts. We will support projects delivering simulations of current and future (i.e. G6- and G7-) GeoMIP experiments by modeling centers using sufficiently capable earth system models, and will favor applications from groups running models which have not recently contributed GeoMIP simulations. In addition to funding, the Reflective team (including GeoMIP co-chair Daniele Visioni) can also provide advice on conducting the GeoMIP experiments and are happy to discuss individual proposal scope ahead of submission (email us at grants@reflective.org if interested in an individual conversation).

Research Goals

We are seeking proposals to deliver new simulations of current and upcoming GeoMIP experiments.

We are seeking proposals for projects which will conduct simulations of current GeoMIP experiments in earth system models with the capability to do so. Such models include several classes:

• Chemistry climate models with interactive stratospheric aerosols and coupled ocean.
• Chemistry climate models with a CMIP-participating low-top version including a coupled ocean. In this case, the model family contains all necessary components to run GeoMIP SAI experiments with interactive aerosols, but these are not currently being used in coupled form. We will support research time to set up and test a model version with these components coupled together, as well as to conduct the simulations.
• Low-top models or those without interactive aerosols, with clear justification for why the model would still represent a valuable addition to GeoMIP, and a clear plan for how prescribed aerosols could be implemented in the model.

We encourage proposals which plan to simulate all of the Tier 1 GeoMIP7 SAI experiments as described in Visioni et al. (2026), and/or their CMIP6 versions. These are:

• G7-1.5K-SAI, G7-1.5K-SAI-END and G7-1.5K-HiLLA; and/or;
• G6-1.5K-SAI, G6-1.5K-SAI-END and G6-1.5K-HiLLA

We will support projects simulating either or both of the CMIP6- and CMIP7-era scenarios in models of either era, depending on the project timeline and availability of model versions and the reference scenarios. The G7- experiments are described in Visioni et al. (2026); G6-1.5K-SAI in Visioni et al. (2024) and Lee et al. (2026); and G6-1.5K-HiLLA in Visioni et al. (2025) and Duffey et al. (2026). See Figure 1 from Visioni et al. (2026) for an overview of these different experiments. In each case the G7- version of the experiment is identical in specification to the G6- version except for the background scenario. Carrying out these simulations also requires simulating preparatory experiments, as described by Visioni et al. (2026; their Table 1). Simulating additional GeoMIP experiments, such as Marine Cloud Brightening (MCB) and Tier 2 experiments, is welcome but not essential.

This funding aims specifically to increase the number and variety of models participating in GeoMIP. As such, we will favor proposals for models which have not recently contributed to GeoMIP (see Appendix).

If uncertain, please reach out to us – we are happy to discuss whether individual proposals meet our scope and to have calls with prospective applicants. Or submit questions via our Q&A form. You may view all submitted questions via the Q&A board.

Proposals should also describe what data outputs will be saved, and how these will be sustainably and publicly stored. We encourage proposals to consider the CMIP7 data requests, including the Baseline Climate Variables (Juckes et al. 2025) and priorities for different communities (e.g. Dingley et al., 2026; McPartland et al., 2026; Fox-Kemperer et al., 2026), and for impacts (Frieler et al., 2024) and regional climate modeling, as described in Visioni et al. (2026; their section 5). CMOR-ization of outputs and uploading data to the Earth System Grid Federation is welcome but not required. Grantees will be asked to provide a subset of outputs to host on the Reflective Cloud Hub so that they are easily available for other researchers; delivery of cloud-optimised (zarr) data for this purpose is preferable but not essential. Proposals must also include the hosting of a primary set of outputs in a long-term, public, location such as the NCAR GDEX, UK CEDA archive, or Earth System Grid Federation.

Out of Scope activities

The following is considered out of scope for this RFP.

• Substantial model development, beyond coupling together existing modules and making minor modifications
• Simulating the ScenarioMIP experiments used as background and counterfactual for the GeoMIP experiments (e.g. SSP2-4.5, or “Medium-Low” for CMIP7; Van-Vuuren et al., 2026)
• Simulating other CMIP experiments.

Eligibility

• This grant is targeted at climate modeling centers. It is open to academic institutions, non-profits, government-affiliated organizations, and similar groups.
• There are no restrictions on country of origin, and projects from the Global South are highly encouraged.
• Only one application may be submitted by the same organization/PI.
• Proposals may be submitted by individual investigators or multi-PI teams from the same or different institutions.

Data, Reporting, and Final Deliverables

Minimum Deliverables

1. Completed GeoMIP simulations (see above) with outputs uploaded to a public long-term data store and the Reflective Cloud Hub.
2. A brief report (see below) documenting the simulations, delivered to Reflective and posted on a DOI’d public repository such as Zenodo.

Open-Access Guidelines

• We require any papers supported through this funding to be published as open-access.
• Consistent with our 501(c)(3) status, grant funds may not be used for the purposes of commercial technology development, marketing communications, business development activities, or any other activities directed at generating a profit.

Reporting Requirements

Awardees will be required to submit a short mid-point report updating the Reflective team on progress with simulations. A final report demonstrating a brief validation of the final simulations is also required, and must be posted on a DOI’d public repository, such as Zenodo, as well as shared with Reflective. This report should include figures showing evolution of some high-level metrics of the climate, including global mean temperature, global mean precipitation, stratospheric aerosol optical depth, and other variables of the team's choice.

Application Process and Budget Requirements

Phases

This funding opportunity is expected to operate over two to three phases. The Phase 1 due date is Nov 2, 2026. We are operating this fast turn-around initial phase in order to allow centers to begin simulations as early as possible. A second phase of applications will be open until Jan 18, 2027. Depending on the funding awarded in phases 1 and 2, a third phase may open.

Timeline and Due Dates

1. Submit a proposal using this form by your preferred Phase deadline.
   1. Phase 1 Due Date: November 2, 2026
   2. Phase 2 Due Date: January 18, 2027
   3. Important notes
      1. There is one pool of funding across both phases. Funding is awarded first to Phase 1 then to Phase 2.
      2. A preview of application questions can be reviewed below.
2. We anticipate notifying applicants of the proposal outcome within 3 weeks of submission with an anticipated project start date within 1 month of award notification.
   1. Phase 1 Dates
      1. Notification of outcome: November 23, 2026
      2. Anticipated Start Date: January 1, 2027
   2. Phase 2 Dates
      1. Notification of outcome: February 8, 2027
      2. Anticipated Start Date: March 8, 2027
   3. Important notes
      1. Where possible, we would like grantees who are able to begin work while contract negotiations are underway.
      2. Applications in Phase 1 may be waitlisted until applications for Phase 2 are received and reviewed.

Awardees will be required to submit a mid-point report and a final report with any promised deliverables.

Estimated Funding & Period of Performance

Our goal is to maximize the number of models contributing to GeoMIP under this grant by funding as many modeling centers as possible, so projects well under budget will be favored. Projects with higher budgets than the maximum will not be immediately ruled out, but must be accompanied by sufficient explanation of the necessity of the additional cost.

Budget Categories

Applicants will be asked to fill out a budget workbook to outline project costs.

• Personnel: Includes salary & benefits for all personnel involved.
• Travel: Includes flights, accommodations, transportation and per diem for any travel required to complete the objectives of the grant.
• Equipment & Supplies: Items needed to complete the project
• Publications: we require grantees to submit papers to open access scientific journals. If the most relevant journal for your research is not open access, please provide further context in your proposal.
• Indirect: Costs not directly relevant to the project but important for operations. Please see Reflective’s indirect cost policy for more information.
• Miscellaneous/Other: Expenses that do not fit into the categories above (e.g. conference registration fees)

Allowable Expenses

• Personnel
  • For academic faculty on an academic year salary in PI or co-PI roles, the grant can provide up to one month of summer salary support and related benefits. These salary funds are not substitutional (cannot be used to relieve a university of salary costs) and cannot be used to reduce teaching loads below the departmental norm.
  • For staff and research scientists in PI or co-PI roles, the grant can provide salary support and related benefits.
  • For staff and research scientists not in PI or co-PI roles, as well as postdoctoral, graduate and/or undergraduate research assistants, the grant can provide salary support and related benefits, including graduate student tuition.
• Travel
  • Domestic or international travel for one project member to attend a GeoMIP annual meeting, per the travel policies of the awardee institution.
  • Support for visitors and collaborators, including domestic and international travel.
• Research equipment, supplies, and other expenses directly related to the research, including publication expenses and professional membership dues.
• Partial support towards computational and data storage.
• The standard indirect cost rate for Reflective grants is 10%. Institutions with federally negotiated indirect rates may request up to 20% indirect costs per Reflective’s policy.
• For any publications associated with Reflective funded research, we require grantees to submit to open access scientific journals. If the most relevant journal for your research is not open access, please provide further context in your proposal.
  • We typically allocate up to $1,500-$3,000 for publication fees, but exceptions may be made with compelling justification.
• If you are collaborating on a proposal with another institution, please fill out the Budget Worksheet with Collaborator(s) tab in the budget worksheet.

Evaluation Criteria

Initial Eligibility Screening

The first phase of evaluation is an eligibility screening. This screening will include checks for the following:

• Eligible organization/institution type
• Within budget guidelines of the RFP
• Within project period of performance guidelines of the RFP
• High level check on alignment with RFP Goals

Evaluation

Applications that pass the eligibility screening will be evaluated by the Reflective team. The areas of evaluation are as follows:

• Impact & Technical Feasibility
  • Level of alignment with RFP goals
  • Feasibility of the project plan
  • Value of adding the proposed model. This represents a combination of model performance against observed bench-marks, difference from other participating models, and technical sophistication (see Appendix for details on current model participation)
  • Value of the proposed data outputs and storage plan, for diverse communities of users
  • Rapidity of proposed delivery of simulations
• Work Plan Efficacy
  • Evaluation of the reasonableness of the budget and timeline and whether the project team has the resources and capabilities needed to complete the work
  • Notable risks and strength of the proposed mitigation strategies

Application Content Requirements

Proposal Formatting

• Submitted in PDF format
• Max 5 pages including figures, data, and visuals
• All text must be a minimum of 10 point font
• Margins should be at least 1 inch on all sides
• Include page numbers in the footer on all pages
• Include the PI name and organization in the header on all pages
• References may extend beyond the 5 page limit.

Proposal Content

Each proposal must include the information outlined in this section. We strongly recommend using the section headers described below, but you may alter/modify this to suit the needs of your project.

• Section 1: Project Plan (~2-3 pg)
  • Model Specification and Validation: Detail the model to be used and its validation relevant to SAI.
    • If available, this should include at least 5 references of papers where the model has been used or showing the capacity of the modelers to run it, as well as appropriate literature showing validation of the model’s representation of stratospheric aerosols where appropriate.
    • If no existing literature is available for model validation, this should include figures demonstrating the model’s capability, for example, by showing the simulated response to a Pinatubo experiment.
  • Technical Description & Methodology: Explain in detail the technical plan and methodology for your proposed project including:
    • which simulations will be conducted and the number of ensemble members
    • which outputs will be saved and how these will be stored and distributed (including to ESGF and CMOR-ization or cloud-optimization if applicable)
    • the methods for implementing GeoMIP protocols, particularly if direct injection of SO2 cannot be simulated in the model
    • a description of the computational infrastructure which will be used and the capabilities of the group to conduct simulations
  • Timeline & Milestones: Please provide an estimated timeline for the project, including specifics about when you expect to complete certain milestones.
  • Final Deliverables: Please explain how you will align with the expected final deliverable(s), below, and any additional planned deliverables.
    • Completed GeoMIP simulations (see above) with outputs uploaded to a public long-term data store and the Reflective Cloud Hub.
    • A brief report documenting the simulations, delivered to Reflective and posted on a DOI’d public repository such as Zenodo.
  • Risks & Mitigation Strategies: Please share any risks that could derail the timeline, budget, or ability to deliver the project deliverables and how you will mitigate said risks.
    • Note: We recommend table format for this.
• Section 2: Project Team & Budget (~1-1.5 pg)
  • Team: Share the background of each project team member, their affiliation, and what they will contribute to the project. Where possible, please include some indication of how much time the person will commit (e.g. full-time, part-time, advisor etc.)
    • Note: We recommend doing this in table format
  • Budget Justification: Please provide narrative context on your budget workbook including details like how budget amounts were calculated and what travel/conferences are included and why.
• Section 3: Current and Pending (<0.5 pg)
  • Current grants, including project goals, timelines, and any overlap with this proposal.

Application Form Questions

The following is a copy of the application form to help you prepare your application materials in advance. The software we use will save a copy of your responses locally to your computer and browser, but we recommend preparing your responses beforehand in a separate document before submission. Questions marked with an asterisk are required.

Section 1: Applicant Details

1. Organization/Institution Name*
2. Primary Principal Investigator (PI) Title*
3. PI First Name*
4. PI Last Name*
5. PI Email Address*
6. How did you hear about this funding opportunity?*
7. What regions are represented on your project team?*
   1. Africa
   2. Asia
   3. Europe
   4. Latin America & Caribbean
   5. U.S./Canada
   6. Middle East
   7. Oceania
8. Model Type
   1. Chemistry-climate models with interactive aerosols and coupled ocean
   2. Chemistry-climate models with a low-top version with coupled ocean
   3. Low-top models or those without interactive aerosols
   4. Other (please briefly describe)

Section 2: Project Proposal

1. Project Title*
2. Please submit a proposal outlining answers to the questions described in the “Proposal Content” section of the RFP. All proposals must be in PDF format and a max of 5 pages (including figures, data, and visuals). References & citations may extend beyond the 5 pages.*
3. Please upload ONE file with the resumes/CVs of all project team members with the PI as the first resume in the file. Please submit as a PDF*
   1. Max 2 pages per resume/CV in the file.
4. How long will your project take (in months)?*
5. What is your total budget for this project?*
6. Upload your budget justification workbook* (make a copy of and fill in this template)

Appendix - current GeoMIP model participation

Up to date information on model participation in recent GeoMIP experiments is held in this spreadsheet. At the time of writing, the models which have completed the G6-1.5K-SAI (and -HiLLA) experiments are shown in the table below. The table also shows some model features and details of their lineage, to inform assessment of a potential additional model’s difference or similarity against the current set. See Lee et al. (2026) for a more detailed overview of the models’ stratospheric sulfate representations.

Reference Links:

• Danabasoglu et al., 2020
• Mulcahy et al., 2023
• Xie et al., 2025
• Kawamiya et al., 2020