1. Adrian Simmons Lead author, Status Report for the Global Climate Observing System Consultant, European Centre for Medium-Range Weather Forecasts Report on the Status of the GCOS Status Report AOPC, Zűrich, 17-20 March2015

3. The GCOS Adequacy Reports and origins of the ECVs Notions of “Principal Observations” and “Key Variables” emerged in the 1990s ‒ in a US National Research Council report, and in GCOS plans GCOS published its First Adequacy Report in 1998 ‒ addressed to the Parties to the UNFCCC ‒ following a request by the UNFCCC COP 3 in 1997 addressed to SBSTA, for a report produced in consultation with the IPCC GCOS published its Second Adequacy Report in 2003 ‒ under the endorsement by SBSTA of its preparation ‒ addressed to the Parties to the UNFCCC ‒ introducing the “Essential Climate Variables” (ECVs)

4. The assessment cycle Following the Second Adequacy Report in 2003, GCOS produced: ‒ an Implementation Plan in 2004 ‒ a Supplement to the Plan in 2006 on requirements for satellite-based data products ‒ a Progress Report in 2009 ‒ an updated Implementation Plan in 2010 ‒ an updated Satellite Supplement in 2011 UNFCCC/SBSTA: ‒ welcomed the 2010 Plan and urged Parties to work towards implementation ‒ invited a subsequent progress report and encouraged a review of adequacy ‒ welcomed the timetable proposed by GCOS for ‒ a Status Report in 2015 ‒ a new Implementation Plan in 2016

5. Updating the ECV list The ECV list was first published in 2003 in the Second Adequacy Report The list was updated a little in the 2010 Implementation Plan ‒ revising some wording, naming ocean acidity and ice sheets explicitly ‒ adding ocean oxygen content, soil moisture and precursors for O 3 and aerosols ‒ not adding land-surface temperature ‒ and including supplementary notes stating that: “ecosystems are characterised, inter alia, by a range of biodiversity and habitat properties that are at present too complex to define as an ECV...” “because of the importance of ecosystem changes to the goals of the UNFCCC, such long-term and collocated measurements are recognised in this Plan as ‘Essential Ecosystem Records’.” The list may be updated again in the 2016 Implementation Plan

6. Some of the ways we are assessing progress and current status By evaluating responses to actions from 2010 Implementation Plan Action A2:Obtain further progress in the systematic international exchange of … hourly SYNOP reports and monthly CLIMAT reports... Action A3:Ensure sustained operation of surface met. stations addressing national and sub-national needs … implement additional stations... Action C13:Collect, digitize and analyse … historical … data records … and submit to International Data Centres By evaluating network performance and data-centre holdings By relating to key uncertainties identified in IPCC AR5, and issues raised by WCRP, other programmes, workshops, etc. Drawing heavily on input provided by panel members and others who have completed “ECV tables”

7. Structure of Status Report Executive Summary ‒ need to identify key messages to be communicated here ‒ ~6 headline ones, ~6 cross-cutting ones, ~6 from AOPC, ~6 from OOPC and ~6 from TOPC 1. Introduction 2. International coordination 3. The need for systematic observation 4. The system for global climate observation ‒ nature of climate observation, observing networks and constellations, the ECV concept, climate-system cycles

8. Structure of Status Report 5. General aspects ‒ Introduction ‒ Space-based observation ‒ Generation of data products ‒ Reanalysis ‒ Early instrumental data and proxy reconstructions ‒ Data management and stewardship ‒ Capacity development 7. Oceanic observation 8. Terrestrial observation This section follows that of IP-10. Specific reviews of IP-10 Actions are given in Appendix 1 Actions C1-C23 link with section 5, O1- O41 with section 7 and T1-T49 with section 8.

9. Structure of Status Report 6. Atmospheric observation ‒ Introduction ‒ Surface Networks ‒ Surface ECVs ‒ Upper-air networks ‒ Upper-air ECVs ‒ Networks for atmospheric composition ‒ Composition ECVs 9. Conclusions Appendix 1. Review of Actions Other appendices Section 6 links with reviews of actions A1-A34 in Appendix 1 Sections can be added on non-ECVs, if case is strong and there is potential for them to be named ECVs in IP-16. Text will need to be supplied.

10. Status of atmospheric ECV sections 6. Atmospheric observation ‒ Introduction (drafted) ‒ Surface Networks (drafted) ‒ Surface ECVs (drafted except for precipitation; ECV-table input is awaited still) ‒ Upper-air networks (drafted) ‒ Upper-air ECVs (drafted except for water vapour and clouds; have input) ‒ Networks for atmospheric composition ‒ Composition ECVs 9. Conclusions Appendix 1. Review of Actions Other appendices Still to be drafted. Input was received from GAW/Oksana last year; NDACC co-Chair has enquired about report and subsequently provided input. It was agreed last year that I should liaise with Jim Butler on these sections

11. Schedule Mar/April:Finish domain sections and work on general ones May:Complete General Sections and Executive Summary ‒ will need input from Panel Chairs (or their representatives) June/July:Make version openly available for review July/Aug:Respond to review comments and update September:Finalise Obtain Steering Committee approval Submit to Sponsors and UNFCCC