Systematic observation of the Earth’s climate is a global common good that supports the implementation of the Paris Agreement. The COVID-19 crisis has demonstrated the high vulnerability of the global observing system and its impact on the quality of surface-based weather and climate observations. With current policies and approaches, surface-based weather and climate observations are highly vulnerable and in decline in many countries. As an example, the European Centre for Medium-Range Weather Forecasts observed a dramatic decrease in the number of shared radiosonde data (the most important surface-based data for weather and climate prediction models) of almost 50% in Africa from 2015 to 2020. These numbers do not include a further decline in observations since January 2020 due to the impact of COVID-19.
Poor and declining availability of basic surface-based observational data leads to unreliable weather and climate prediction models. This has negative impacts on the many sectors that depend on these data (e.g., agriculture, transport, insurance), as well as on disaster risk management, adaptation and even mitigation strategies.
