New GCOS report outlines priorities for global climate observations


High priority actions to gather essential information on our climate system and improve monitoring and understanding of how it is changing are outlined in a new report by the Global Climate Observing System (GCOS). Climate observations are vital: they have unequivocally shown that human-induced climate change is occurring, and they have informed the projections needed to successfully adapt to climate change and reduce greenhouse gas emissions.

“All successful actions to adapt to or mitigate climate change must be based on sound accurate information that can only be provided by a global climate observing system. Planning for and mitigating the impacts of climate change, predicting and understanding future risks, and protecting vulnerable populations and infrastructures all require global information on the changing climate,” said WMO Secretary-General Prof. Petteri Taalas.

“Global climate monitoring needs to cover the entire Earth system from the atmosphere to the oceans, from the cryosphere to the biosphere, and encompassing the water cycle and energy and greenhouse gas budgets,” he said. WMO is one of the co-sponsors of GCOS.

GCOS regularly produces status reports, which assess the progress and unmet requirements in the climate observing systems, followed by implementation plans, which propose actions for its improvement. The 2022 GCOS Implementation Plan provides critical input to the United Nations Framework Convention on Climate Change (UNFCCC) and will be presented to the UN climate change negotiations, COP27, in November.

Essential Climate Variables
Essential Climate Variables

GCOS collects and documents the data needs for monitoring the climate system and assessing the impacts of climate variability and change, using satellite and in-situ, ocean, atmosphere and land observations. It monitors 54 “Essential Climate Variables” which are used to characterise the Earth’s climate (including the atmosphere, biosphere, ocean, hydrosphere and cryosphere). These observations inform the WMO’s annual State of the Global Climate reports, and feed into the Intergovernmental Panel on Climate Change assessments, in addition to supporting the UNFCCC process.

The 2021 GCOS Status Report, released last year, identified the successes and gaps in the existing observing systems. The 2022 GCOS implementation plan presents the major practical actions that should be undertaken in the next 5- 10 year to address these gaps. It identifies six major themes that should be addressed.

  • Ensuring Sustainability. Sustained funding is essential to ensure the continuity and the expansion needed for many observations of Essential Climate Variables. Many observations are supported through short-term funding, leaving the development of long-term records extremely vulnerable. Satellite observations have been a major success in monitoring many ECVs, but the long-term continuity of some satellite observations is not assured.
  • Filling Data Gaps. There are big gaps for many  in-situ observations over parts of Africa, South America, Southeast Asia, in the deep ocean and polar regions. There has been no improvement since the last GCOS Status report in 2015.
  • Improving data quality, availability and utility. Many climate observations are currently underexploited because of the lack of consistency in their processing and usability. Further effort is required towards ensuring data could be readily used in reanalysis and is fit for purpose.
  • Managing Data. To address and understand climate change, the longest possible time series need to be preserved and made available in perpetuity. All climate variables need sustainable global data repositories with free and open access to data. Data rescue from hard copy or archaic digital formats allows data series to be extended and needs to be adequately planned and funded with the results openly and freely available.
  • Engaging with Countries. Many climate observations are made by national bodies, which need support and regional and global coordination. The benefits of climate observations need to be widely understood and the contributions of national observations to global datasets enhanced.
  • Emerging Needs. Stakeholder needs are evolving. GCOS Expert Panels have already identified several areas where emerging needs arising from response measures such as adaptation and mitigation need to be addressed in the short term. GCOS is looking at how observations more generally can support adaptation.

There is an ongoing need to understand the changing climate system. At a fundamental level what we do not observe we cannot understand, and what we cannot understand we cannot predict, adapt to and mitigate. It is necessary to observe, on a sustained basis, key facets of the climate system, in order to monitor and understand the changing climate,” said Prof. Peter Thorne, Chair of the GCOS Atmospheric Observation Panel for Climate.

“Recent scientific studies of how well the climate cycles of carbon, water and energy are monitored have identified additional observational needs that if addressed would improve scientific understanding, models and projections”, said Prof.  Han Dolman, Chair of the GCOS Steering Committee.

“Ocean observations deployed in the last three decades have shown that the ocean is central in shaping the Earth climate at all scales. To enhance climate mitigation, adaptation and provide parties with  high quality  information, it is necessary to improve and maintain a global ocean observing system, extending from the coasts to the polar regions, from surface to the ocean floor”, says Prof. Sabrina Speich, Chair of the Ocean Observations Physics and Climate Panel.

“Monitoring changes in the terrestrial system is critical to understand both the effect of actions to reduce the human influence in the climate system as well as to identify the need for response measures, such as adaptation and mitigation. The systematic updating and availability of the essential climate variables allow models to be continuously improved, thus making their predictions and projections of future changes more robust.” says Dr. Thelma Krug, chair of the GCOS Terrestrial Observation Panel for Climate.

The Global Climate Observing System programme is co-sponsored by WMO, the Intergovernmental Oceanographic Commission of UNESCO, the United Nations Environment Programme (UNEP) and the International Scientific Council (ISC).

IGRAC's contribution to GCOS

The ECVs that are coordinated by TOPC are divided in four categories: cryosphere, anthroposphere, biosphere and hydrosphere. ECV groundwater is one of the five ECVs that are part of the latter, together with river discharge, lakes, soil moisture and evaporation from land.

IGRAC has been contributing to GCOS since 2011, by providing expert advice on the ECV groundwater definition and requirements, and also by proposing and implementing action items of the programme. In particular, the Global Groundwater Monitoring Network (GGMN) was set up as a ‘network of networks’ to improve accessibility to groundwater monitoring data and information, which contributes to the goals of GCOS.

Moreover, IGRAC contributes to the Global Terrestrial Network for Hydrology (GTN-H).