The TOPC is a group of scientists with expertise in climate change issues. The TOPC supports the work of the Global Terrestrial Observing System (GTOS) and the Global Climate Observing System (GCOS) which jointly carry out activities aimed at improving the understanding of climate change processes in terrestrial systems and potential impacts on mankind.

The TOPC focuses on the identification of terrestrial observation requirements, assisting the establishment of observing networks for climate, providing guidance on observation standards and norms, facilitating access to climate data and information and its assimilation, and promoting climate studies and assessments.

The chair of the TOPC is a subsidiary member of the steering committee's for GTOS and GCOS and reports the results of the TOPC deliberations and work directly to those bodies.

TOPC is jointly sponsored by GCOS, GTOS and by the World Climate Research Programme (WCRP).

TOPC strategy for 2007-2011

Although climate change is now firmly established, there is still considerable uncertainty about the rate of change and its regional variability. Precise quantification of the rate of change remains important to determine whether feedback or amplification mechanisms are operating within the climate system. Unfortunately, the climate observing system in the terrestrial domain still remains the least well-developed component, whilst at the same time there is increasing significance being placed on terrestrial data for both climate understanding as well as impact and mitigation assessment.

Foundations exist for both the in situ observation networks and the space-based observing components of the terrestrial domain. Space Agencies and other organizations are generating new products, the Global Terrestrial Networks (GTNs) are being established and growing in effectiveness, and their associated international data centres are beginning to be populated with data.

TOPC has played an important role in establishing standards for the terrestrial climate variables within its overall mandate of improving the understanding of the terrestrial components of the climate system, the causes of change to this system and consequences in terms of impact and adaptation. Changes in the context of both the status of ECV’s and the need for new ones required for impact and mitigation studies require some re-establishment of the focus of TOPC. These concern:

1. To define the requirements for long-term monitoring of terrestrial properties for climate and climate change;

2. To liaise with relevant research and operational communities to identify measurable terrestrial (biosphere, cryosphere, and hydrosphere) properties and attributes which

control the physical, biological and chemical processes affecting climate,

are themselves affected by climate change, are indicators of climate change and provide information on impacts of climate change;

3. To assess and monitor the adequacy of terrestrial observing networks (in-situ, satellite-based), promote their integration and promote the development of their capacity to measure terrestrial properties and exchange climate data and information;

4. To identify gaps in present systems and design, promote and periodically revise plans for a long-term systematic observing system that fills these gaps, makes the data available and so better serves the needs of the research and operational communities;

5. To coordinate activities with other global observing system panels and task groups to ensure consistency of requirements with the overall programmes;

6. Publish and update GCOS/GTOS studies and planning documents;

7. To liaise with the other GCOS panels, WCRP steering groups and other relevant entities, such as WMO Commissions and CEOS, on terrestrial climate observing system issues., and also to other GTOS panels, where relevant;

8. Carry out agreed assignments from the GCOS and GTOS Steering Committees;

9. Report regularly to the GCOS Steering Committee and GTOS Steering Committee on issues related to the terrestrial component of GCOS.