Current scientific studies of global change, based on existing data sets and models, have shown that human activities have an enormous potential for producing climatic and biological consequences. Unfortunately, given the critical observational limitations researchers now face, even the most comprehensive models produce results with large uncertainties.
Scientists need long-term, consistent measurements of the key physical variables that define the shifts in state and variability of the Earth system components. Lacking these measurements, predictions of the complex responses of the Earth system to human activities and natural variations lack an adequate basis for developing and validating global predictive models and for establishing a baseline to determine trends. Space-based observations hold the key to making progress, because satellites best capture a consistent, global perspective.
EOS is observing the key physical variables needed to advance understanding of the entire Earth system and develop a deeper comprehension of the components of that system and the interactions among the components. By enhancing understanding of the processes involved, EOS is helping discriminate between human-induced and natural changes. The 24 EOS Measurements include the highest priority measurements needed for each of the Earth system components -- the atmosphere, the land, the oceans, the cryosphere, and the solar driving force. To quantify changes in the Earth system, EOS is providing systematic, continuous observations from low Earth orbit for a minimum of 15 years.
To view a PDF version of the 24 EOS Measurements, access the link below. Please note that the EOS instruments listed in this document are indicated in bold font for primary sensors, bold italic for secondary,and roman for contributing instruments to critical measurement. To properly view this document you will need Adobe Acrobat Reader*
Download the 24 Measurement Sets
