1. Description of an Essential Variable Breakout Session 2.1: Essential Variables for Sustainable Development Goals, Global Boundaries and Safe Operating Space for Humanity Chair: Hans-Peter Plag Rapporteur: Senay Habtezion Breakout Sessions Block 1: Designing the Metrics 3rd GEOSS Science and Technology Stakeholder Workshop NAVIGATING SUSTAINABILITY ON A CHANGING PLANET March 23-25, 2015, Norfolk, VA, USA

2. Essential variable – Key questions 1.WHAT: Definition of EV 2.WHY: Why should GEOs provide description of indicators? 3.HOW: What process is desirable and feasible to provide description of Evs? 4.WHO: Who would use a template for description of EVs (communities of practice)

3. Designing the Metrics Recommended TEMPLATE for the description of an Essential Variable Describe the societal goal(s) that have a linkage to the EV Describe the societal target(s) or equivalent entities that are linked to the indicators Describe the indictor(s) that depend on the EV Describe the system relevance of the EV, where system is the coupled human-natural system. Provide details on the earth system components for which the EV is essential Describe operational, forecasting, and discipline-specific relevance of the EV Describe the underlying data organization/management for the EV Describe the benefits of having the EV available

4. WHAT is essential variable? What is an essential variables? Suggested definition: Variables that determine the system’s state and developments, are crucial for predicting system developments, and allow us to define metrics that measure the trajectory of the system. Limited knowledge of essential variables implies limited predictive capabilities and limited means to measure where the system is heading. – Additional suggestions: There may be a need to rephrase the suggested definition such that the there are two parts: one addressing the technical aspects of EV and the second dealing with Societal relevance Essential variables are crucial for the creation of practice-relevant knowledge (reflect in definition?) Essential variables are closer to knowledge than others.

5. Essential variable – concerns 1. EVs are domain specific – Different communities of practice have different approaches and are likely to characterize their variables their way -Consensus: The goal of GEOS is to recommend a process for determining EVs not prescribe domain-specific variables 2. How can we proceed and facilitate a coordinated discussion/deliberation of EVs in GEO?