The Role and Importance of Long-term, Surface-based, in situ Observations in Understanding the Earth System
Abstract
Observations provide the foundation of all of our understanding of climate, weather, and ecosystems. We know what we know today largely because we have been able to observe planet Earth in many ways. From observations, we are able to build our understanding of the Earth system. And from this improved understanding, we are able to develop and improve predictions of climate, weather, and ecosystem behavior. These observations come in all forms, the most commonly recognized are those from satellites. But the beating heart of our networks of Earth observations derives from those that are based at Earth's surface. Clearly, observations from satellites provide fantastic global coverage and capture many features of our planet, its atmosphere, its oceans, and terrestrial-based ecosystems. But satellites typically retrieve radiances within spectra, radiances must be turned into meaningful units, orbits decay, and instrument responses drift. The accuracy and continuity of observations from satellites depends intrinsically upon long-term, surface based observations, which are traceable to international standards and internally compatible across the globe through on-going, rigorous quality control. And there are observations that simply cannot be done by satellite, many of which provide essential information for understanding our Earth system and informing societal and policy decisions. This presentation provides an overview of several of these long-term, surface-based observing systems, demonstrating their unique value or their importance in supporting satellite retrievals. It also takes a look at our coming challenges and how we might improve on all observing systems in order to improve our understanding and therefore our predictions on all spatial and temporal scales.
