Phase 1 - Overview

Welcome to CalLMIP Phase 1! The goal of the Phase 1 experiments is to evaluate how well models' existing ("in-house") parameter calibration efforts reduce model-data misfit and the spread across models for key variables.

In Phase 1 we are taking a ‘come as you are’ approach, which is to leverage existing/current model parameter estimation systems, rather than requiring development of new systems or tests of different calibration configurations. With this approach, we hope to maintain flexibility to include a wide array of models with their existing calibration systems.

In Phase 1 we will also have a focus on site-level calibration focusing only on the most common observations measured at flux tower sites: net ecosystem exchange (NEE), latent heat flux (Qle) and sensible heat flux (Qh). Other key ecosystem variables – such as LAI, above and belowground carbon stocks and soil moisture – will be the target of future phases of CalLMIP. Regional to global scale (as well as coupled) parameter calibration experiments will also be a target for future CalLMIP Phases.

Our hope is that Phase 1 is a starting point from which additional analyses and experiments will develop. We will outline the vision for future CalLMIP phases from the CalLMIP Steering Committee and discussion at the 1st Phase Planning workshops held in March and April 2025 in a perspective article to be submitted in spring 2026.

Please see the Getting Started page and the Protocol for more information and a proposed timeline for the Phase 1 experiments.