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Over a two-year period beginning in 2015, a panel of subject matter experts, the Space Platform Requirements Working Group (SPRWG), carried out an analysis and prioritization of different space-based observations supporting the National Oceanic and Atmospheric Administration (NOAA)’s operational services in the areas of weather, oceans, and space weather. NOAA leadership used the SPRWG analysis of space-based observational priorities in different mission areas, among other inputs, to inform the Multi-Attribute Utility Theory (MAUT)-based value model and the NOAA Satellite Observing Systems Architecture (NSOSA) study. The goal of the NSOSA study is to develop candidate satellite architectures for the era beginning in approximately 2030. The SPRWG analysis included a prioritized list of observational objectives together with the quantitative attributes of each objective at three levels of performance: a threshold level of minimal utility, an intermediate level that the community expects by 2030, and a maximum effective level, a level for which further improvements would not be cost effective. This process is believed to be unprecedented in the analysis of long-range plans for providing observations from space. This paper describes the process for developing the prioritized objectives and their attributes and how they were combined in the Environmental Data Record (EDR) Value Model (EVM). The EVM helped inform NOAA’s assessment of many potential architectures for its future observing system within the NSOSA study. However, neither the SPRWG nor its report represents official NOAA policy positions or decisions, and the responsibility for selecting and implementing the final architecture rests solely with NOAA senior leadership.

Environmental satellites today are designed to meet the most requirements possible within the constraints of budget, reliability, availability, robustness, manufacturability, and the state of the art in affordable technology. As we learn more and more about observing and forecasting, requirements continue to be developed and validated for measurements that can benefit from for advances in technology. The goal is to incorporate new technologies into operational systems as quickly as possible. Technologies that exist or are being developed in response to growing requirements can be categorized as "requirements pull" whereas technologies rooted in basic research and engineering exploration fall in to a "technology push" category.NOAA has begun exploration into technologies for future NOAA satellite systems. Unmet requirements exist that drive the need to locate, explore, exploit, assess, and encourage development in several technologies. Areas needing advanced technologies include: atmospheric aerosols; cloud parameters; precipitation; profiles of temperature, moisture, pressure, and wind; atmospheric radiation; trace gas abundance and distribution; land surface; ocean surface; and space weather components such as neutral density and electron density.One of the more interesting ideas in the technology push category is a constellation of satellites at Medium Earth Orbit (MEO) altitudes, here described as circular orbits near 11,000 km altitude. Consider the vision of being able to observe the environment anywhere on the Earth, at anytime, with any repeat look frequency, and being able to communicate these measurements to anyone, anywhere, anytime, in real time. Studies suggest that a constellation of MEO satellites occupying equatorial and polar orbits (inclination = 90 degrees) could, in principle, accomplish this task.Also new on the horizon is solar sail technology. NOAA has been looking at solar sails as providing a propulsive system that could be used to maintain a satellite in a position closer to the Sun than L1. L1 is that point between the Earth and the sun where the gravitational forces of the Earth and the sun are equal. The sail would allow the increased gravitational force from the Sun to be balanced by the propulsive force of the solar sail. This capability could increase the lead-time for measuring and predicting the impact of solar events. Solar sails could also allow a satellite to be positioned over the Earth's polar regions continuously, filling a critical gap in current orbital observations and services.The combination of these technologies will enable the NOAA Satellites and Information Service to meet important requirements currently unmet and help satisfy NOAA strategic goals.

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Thirty months of continuous low resolution statellite measurements of albedo and emitted longwave radiation are used to study precipitation associated with the Indian Monsoon. Combined with rainfall data for the Indian subcontinent, the satellite data are employed to develop a precipitation intensity index. It is postulated that such an index must first adequately depict the extreme monsoon rainfall regime before it can be applied to the study of rainfall over other regions, especially those devoid of conventional precipitation measurements.Three monsoons are studied to develop the index: the 1963 monsoon, the strong 1964 monsoon and the very weak 1965 monsoon. The apparently successful quantitative measure of monsoon intensity by use of the precipitation intensity index was checked using independent data for the same region in i966 and 1969. With the aid of the index the time history of the 1964 and 1965 monsoons are examined showing how the intense cloudiness of the 1964 monsoon lingered for a number of months apparently reducing surface heating significantly preceeding the weak 1965 monsoon. This two-parameter, bi-spectral remote sensing method using satellite data can be tested for other regions using currently available satellite measurements.