Introduction
For the WCRP Years of Precipitation (YoP) activities, GPEX will identify crucial partners and necessary infrastructure to coordinate field campaigns in high priority regions that have a duration of at least one month and, where relevant, sample across different seasons. Therefore, GPEX is to seek and encourage large GPEX-endorsed projects as anchors for global field campaigns and then entrain additional projects from various countries. GPEX will use the same vetting mechanism as the Year of Polar Prediction (YOPP 2016) for the endorsement of these projects.
GPEX is motivated by the recognition that, despite some progress over the past few decades (e.g., through WCRP core projects, such as GEWEX, CLIVAR, APARC), the required improvement of precipitation predictions has been hampered by major gaps in observing, understanding, and modeling precipitation. Extreme events like floods and debris flows are often caused by extreme precipitation and projected to be exacerbated by a warmer climate. Accelerated improvements in the provision of precipitation products are needed to help emergency managers, water resource managers, and infrastructure planners better respond to and prepare for precipitation changes and mitigate their impacts on communities and ecosystems.
Criteria for endorsement
- Must be precipitation focused
- Must involve two or more countries
- Must be funded – at least a total of USD 5 million (equivalent)
- Must be open to collaborations
- Must provide data dissemination and access plan
- Must include capacity development plan (definition, how your project plans to support capacity development – provide examples : such as adhering to the SDGs)
- Roadmap and coordination plan with tangible GPEX objectives
Endorsed projects
- "AR-Recon: https://cw3e.ucsd.edu/arrecon_overview/" Atmospheric River Reconnaissance – First GPEX “Anchor Project” (approved June 2025)
Identified by GPEX as a major storm type, ARs are transient, elongated corridors of concentrated water vapor transport that can produce precipitation resulting in either beneficial water supply or hazardous flooding. AR Recon supports scientific research and operational activities related to better understanding precipitation processes and better forecasting extreme precipitation. This program is also recognized in the ARROW Act, signed by President Biden in 2023, and in the bipartisan AR Forecasting Bill officially introduced in the U.S. Senate. AR Recon is collaborating with international field campaigns—such as NAWDIC and DOTSTAR—as it expands globally and advances AR science, serving as an anchor project supporting GPEX.
How to apply for endorsement
To apply for GPEX endorsement of a field campaign, please follow the steps below:
- Ensure eligibility
First, confirm that your proposed campaign aligns with the endorsement criteria outlined above. - Prepare a proposal
Download the GPEX Field Campaign Proposal Template and complete it according to the instructions provided - Submit your proposal
Send the completed proposal to the co-chairs of WG1 Prof. Fred (Marty) Ralph (This email address is being protected from spambots. You need JavaScript enabled to view it. ) and Dr. Samson Hagos (This email address is being protected from spambots. You need JavaScript enabled to view it. ) and copy the WCRP Secretariat Scientific Officer Hindumathi Palanisamy (This email address is being protected from spambots. You need JavaScript enabled to view it. ). - Review and decision
Your proposal will be reviewed by WG1. Following this review, it will be submitted to the GPEX SSG for final consideration and decision
Contact and further information
WCRP Secretariat Contact: Hindumathi Palanisamy (