POEM-PBSim

A Simulator for Earth's Planetary Boundaries
 

POEM-PBSim: A Simulator for Earth's Planetary Boundaries

Project Overview

The planetary boundaries framework has been introduced to define a safe operating space for humanity given the multitude of anthropogenic pressures on vital components of the Earth system. Despite their substantial importance for national and international policy processes on sustainable development, Earth's planetary boundaries remain only poorly defined and quantified, mainly due to non-linear feedbacks in the Earth system and non-trivial interactions between different Earthsystem components. Fundamental scientific progress along these lines is urgently needed and requires a novel and integrative Earth-system modelling approach based on fast, modular coupled models including an advanced representation of the terrestrial biosphere. The focus of this project is to make the prototype of the Potsdam Earth Model (POEM) operational as a planetary boundary simulator (POEM-PBSim) and perform a first quantification of key planetary boundaries.

Using this model configuration, the expertise of the PIK will be integrated to explore several science questions that represent key aspects of the planetary boundary agenda, illustrate the importance of interactions between different components of the Earth system and make use of key strengths of POEM-PBSim in terms of its advanced terrestrial biosphere model and the representation of Earth-system feedbacks. The Earth system components studied (forests, ocean circulation and marine biosphere) are not treated as mere components of the climate system, but as defining dimensions of a "safe operating space for humanity" that may inform the agendas on sustainable development. This pilot project will thus not only provide an operational model system for Earth's interacting planetary boundaries, but also yield next-phase scientific insights on selected planetary boundaries and their interactions.

Key research objectives

  • How do Earth-system components under anthropogenic pressure influence the state of the
    Earth system as a whole?
  • Are there limits and thresholds where certain combinations of processes drive the Earth
    system into altered states of operation when compared to historic precedence?
  • What are limits to change that can be established as planetary boundaries to maintain and
    safeguard the functional integrity of the Earth’s ecosphere, humanity’s one and only habitat?
  • Is there any danger of runaway effects or developments, state transitions or tipping cascades
    developing if certain thresholds of change are transgressed?
  • Which kinds of interventions into humanity’s influence on the Earth system can steer it
    toward a dynamically stabilized Anthropocene amenable to sustainable development?

Team members

Models

Selected publications

Drüke, M., von Bloh, W., Petri, S., Sakschewski, B., Schaphoff, S., Forkel, M., Huiskamp, W., Feulner, G., and Thonicke, K.: CM2Mc-LPJmL v1.0: Biophysical coupling of a process-based dynamic vegetation model with managed land to a general circulation model. Geoscientific Model Development Discussions [preprint], doi:,10.5194/gmd-2020-436, in review, February 2021.