44 research outputs found

    Satellite sensor requirements for monitoring essential biodiversity variables of coastal ecosystems.

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    The biodiversity and high productivity of coastal terrestrial and aquatic habitats are the foundation for important benefits to human societies around the world. These globally distributed habitats need frequent and broad systematic assessments, but field surveys only cover a small fraction of these areas. Satellite-based sensors can repeatedly record the visible and near-infrared reflectance spectra that contain the absorption, scattering, and fluorescence signatures of functional phytoplankton groups, colored dissolved matter, and particulate matter near the surface ocean, and of biologically structured habitats (floating and emergent vegetation, benthic habitats like coral, seagrass, and algae). These measures can be incorporated into Essential Biodiversity Variables (EBVs), including the distribution, abundance, and traits of groups of species populations, and used to evaluate habitat fragmentation. However, current and planned satellites are not designed to observe the EBVs that change rapidly with extreme tides, salinity, temperatures, storms, pollution, or physical habitat destruction over scales relevant to human activity. Making these observations requires a new generation of satellite sensors able to sample with these combined characteristics: (1) spatial resolution on the order of 30 to 100-m pixels or smaller; (2) spectral resolution on the order of 5 nm in the visible and 10 nm in the short-wave infrared spectrum (or at least two or more bands at 1,030, 1,240, 1,630, 2,125, and/or 2,260 nm) for atmospheric correction and aquatic and vegetation assessments; (3) radiometric quality with signal to noise ratios (SNR) above 800 (relative to signal levels typical of the open ocean), 14-bit digitization, absolute radiometric calibration <2%, relative calibration of 0.2%, polarization sensitivity <1%, high radiometric stability and linearity, and operations designed to minimize sunglint; and (4) temporal resolution of hours to days. We refer to these combined specifications as H4 imaging. Enabling H4 imaging is vital for the conservation and management of global biodiversity and ecosystem services, including food provisioning and water security. An agile satellite in a 3-d repeat low-Earth orbit could sample 30-km swath images of several hundred coastal habitats daily. Nine H4 satellites would provide weekly coverage of global coastal zones. Such satellite constellations are now feasible and are used in various applications

    Satellite sensor requirements for monitoring essential biodiversity variables of coastal ecosystems

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    © The Author(s), 2018. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Ecological Applications 28 (2018): 749-760, doi: 10.1002/eap.1682.The biodiversity and high productivity of coastal terrestrial and aquatic habitats are the foundation for important benefits to human societies around the world. These globally distributed habitats need frequent and broad systematic assessments, but field surveys only cover a small fraction of these areas. Satellite‐based sensors can repeatedly record the visible and near‐infrared reflectance spectra that contain the absorption, scattering, and fluorescence signatures of functional phytoplankton groups, colored dissolved matter, and particulate matter near the surface ocean, and of biologically structured habitats (floating and emergent vegetation, benthic habitats like coral, seagrass, and algae). These measures can be incorporated into Essential Biodiversity Variables (EBVs), including the distribution, abundance, and traits of groups of species populations, and used to evaluate habitat fragmentation. However, current and planned satellites are not designed to observe the EBVs that change rapidly with extreme tides, salinity, temperatures, storms, pollution, or physical habitat destruction over scales relevant to human activity. Making these observations requires a new generation of satellite sensors able to sample with these combined characteristics: (1) spatial resolution on the order of 30 to 100‐m pixels or smaller; (2) spectral resolution on the order of 5 nm in the visible and 10 nm in the short‐wave infrared spectrum (or at least two or more bands at 1,030, 1,240, 1,630, 2,125, and/or 2,260 nm) for atmospheric correction and aquatic and vegetation assessments; (3) radiometric quality with signal to noise ratios (SNR) above 800 (relative to signal levels typical of the open ocean), 14‐bit digitization, absolute radiometric calibration <2%, relative calibration of 0.2%, polarization sensitivity <1%, high radiometric stability and linearity, and operations designed to minimize sunglint; and (4) temporal resolution of hours to days. We refer to these combined specifications as H4 imaging. Enabling H4 imaging is vital for the conservation and management of global biodiversity and ecosystem services, including food provisioning and water security. An agile satellite in a 3‐d repeat low‐Earth orbit could sample 30‐km swath images of several hundred coastal habitats daily. Nine H4 satellites would provide weekly coverage of global coastal zones. Such satellite constellations are now feasible and are used in various applications.National Center for Ecological Analysis and Synthesis (NCEAS); National Aeronautics and Space Administration (NASA) Grant Numbers: NNX16AQ34G, NNX14AR62A; National Ocean Partnership Program; NOAA US Integrated Ocean Observing System/IOOS Program Office; Bureau of Ocean and Energy Management Ecosystem Studies program (BOEM) Grant Number: MC15AC0000

    Satellite Sensor Requirements for Monitoring Essential Biodiversity Variables of Coastal Ecosystems

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    The biodiversity and high productivity of coastal terrestrial and aquatic habitats are the foundation for important benefits to human societies around the world. These globally distributed habitats need frequent and broad systematic assessments, but field surveys only cover a small fraction of these areas. Satellite-based sensors can repeatedly record the visible and near-infrared reflectance spectra that contain the absorption, scattering, and fluorescence signatures of functional phytoplankton groups, colored dissolved matter, and particulate matter near the surface ocean, and of biologically structured habitats (floating and emergent vegetation, benthic habitats like coral, seagrass, and algae). These measures can be incorporated into Essential Biodiversity Variables (EBVs), including the distribution, abundance, and traits of groups of species populations, and used to evaluate habitat fragmentation. However, current and planned satellites are not designed to observe the EBVs that change rapidly with extreme tides, salinity, temperatures, storms, pollution, or physical habitat destruction over scales relevant to human activity. Making these observations requires a new generation of satellite sensors able to sample with these combined characteristics: (1) spatial resolution on the order of 30 to 100-m pixels or smaller; (2) spectral resolution on the order of 5 nm in the visible and 10 nm in the short-wave infrared spectrum (or at least two or more bands at 1,030, 1,240, 1,630, 2,125, and/or 2,260 nm) for atmospheric correction and aquatic and vegetation assessments; (3) radiometric quality with signal to noise ratios (SNR) above 800 (relative to signal levels typical of the open ocean), 14-bit digitization, absolute radiometric calibratio

    Satellite sensor requirements for monitoring essential biodiversity variables of coastal ecosystems

    Get PDF
    The biodiversity and high productivity of coastal terrestrial and aquatic habitats are the foundation for important benefits to human societies around the world. These globally distributed habitats need frequent and broad systematic assessments, but field surveys only cover a small fraction of these areas. Satellite-based sensors can repeatedly record the visible and near-infrared reflectance spectra that contain the absorption, scattering, and fluorescence signatures of functional phytoplankton groups, colored dissolved matter, and particulate matter near the surface ocean, and of biologically structured habitats (floating and emergent vegetation, benthic habitats like coral, seagrass, and algae). These measures can be incorporated into Essential Biodiversity Variables (EBVs), including the distribution, abundance, and traits of groups of species populations, and used to evaluate habitat fragmentation. However, current and planned satellites are not designed to observe the EBVs that change rapidly with extreme tides, salinity, temperatures, storms, pollution, or physical habitat destruction over scales relevant to human activity. Making these observations requires a new generation of satellite sensors able to sample with these combined characteristics: (1) spatial resolution on the order of 30 to 100-m pixels or smaller; (2) spectral resolution on the order of 5 nm in the visible and 10 nm in the short-wave infrared spectrum (or at least two or more bands at 1,030, 1,240, 1,630, 2,125, and/or 2,260 nm) for atmospheric correction and aquatic and vegetation assessments; (3) radiometric quality with signal to noise ratios (SNR) above 800 (relative to signal levels typical of the open ocean), 14-bit digitization, absolute radiometric calibration \u3c2%, relative calibration of 0.2%, polarization sensitivity \u3c1%, high radiometric stability and linearity, and operations designed to minimize sunglint; and (4) temporal resolution of hours to days. We refer to these combined specifications as H4 imaging. Enabling H4 imaging is vital for the conservation and management of global biodiversity and ecosystem services, including food provisioning and water security. An agile satellite in a 3-d repeat low-Earth orbit could sample 30-km swath images of several hundred coastal habitats daily. Nine H4 satellites would provide weekly coverage of global coastal zones. Such satellite constellations are now feasible and are used in various applications

    China Near Seas Combat Capabilities

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    The capstone U.S. Defense Department study on the future operational environment declares, China\u27s rise represents the most significant single event on the international horizon since the collapse of the Cold War. Understanding and assessing changes in China\u27s traditionally defensive naval strategy, doctrine, and force structure are of obvious importance to the U.S. Navy (USN) and other Pacific navies concerned with the possible security implications of that rise. This chapter examines the development of the Chinese navy\u27s Houbei (Type 022) fast-attack-craft force and its roles and missions in China\u27s near seas and discusses implications for the U.S. Navy and other navies in the region.https://digital-commons.usnwc.edu/cmsi-red-books/1010/thumbnail.jp

    Observation and integrated Earth-system science: a roadmap for 2016–2025

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    This report is the response to a request by the Committee on Space Research of the International Council for Science to prepare a roadmap on observation and integrated Earth-system science for the coming ten years. Its focus is on the combined use of observations and modelling to address the functioning, predictability and projected evolution of interacting components of the Earth system on timescales out to a century or so. It discusses how observations support integrated Earth-system science and its applications, and identifies planned enhancements to the contributing observing systems and other requirements for observations and their processing. All types of observation are considered, but emphasis is placed on those made from space. The origins and development of the integrated view of the Earth system are outlined, noting the interactions between the main components that lead to requirements for integrated science and modelling, and for the observations that guide and support them. What constitutes an Earth-system model is discussed. Summaries are given of key cycles within the Earth system. The nature of Earth observation and the arrangements for international coordination essential for effective operation of global observing systems are introduced. Instances are given of present types of observation, what is already on the roadmap for 2016–2025 and some of the issues to be faced. Observations that are organised on a systematic basis and observations that are made for process understanding and model development, or other research or demonstration purposes, are covered. Specific accounts are given for many of the variables of the Earth system. The current status and prospects for Earth-system modelling are summarized. The evolution towards applying Earth-system models for environmental monitoring and prediction as well as for climate simulation and projection is outlined. General aspects of the improvement of models, whether through refining the representations of processes that are already incorporated or through adding new processes or components, are discussed. Some important elements of Earth-system models are considered more fully. Data assimilation is discussed not only because it uses observations and models to generate datasets for monitoring the Earth system and for initiating and evaluating predictions, in particular through reanalysis, but also because of the feedback it provides on the quality of both the observations and the models employed. Inverse methods for surface-flux or model-parameter estimation are also covered. Reviews are given of the way observations and the processed datasets based on them are used for evaluating models, and of the combined use of observations and models for monitoring and interpreting the behaviour of the Earth system and for predicting and projecting its future. A set of concluding discussions covers general developmental needs, requirements for continuity of space-based observing systems, further long-term requirements for observations and other data, technological advances and data challenges, and the importance of enhanced international co-operation

    Space Security 2008

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    Provides data and analysis on space activities in 2007 and their cumulative impact on security issues, including space laws, policies, and doctrines; civil space programs and global utilities; commercial uses; and environmental and military issues

    Space Studies Board Annual Report 1995

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    During 1995, the Space Studies Board and its committees and task groups gathered for a total of 40 meetings. Highlights of these meetings are presented. Formal study reports and short reports developed and approved during the meetings and issued during 1995 are represented in this annual report either by their executive summaries (for full-length reports), or by reproduction in full (for short reports). Nine full-length reports were distributed or delivered, including a congressionally mandated report by the Committee on the Future of Space Science and a comprehensive survey of Earth observation programs by the Committee on Earth Studies. Major research guidance reports were completed and published by the Committee on Microgravity Research and by the federated Committee on Solar and Space Physics/Committee on Solar-Terrestrial Research. Several significant assessment reports were also published, including an assessment of small missions by the Committee on Planetary and Lunar Exploration, a scientific evaluation of Gravity Probe B by the Task Group on Gravity Probe B, and an analysis of technologies for a 4-meter active optics telescope by the Task Group on BMDO New Technology Orbital Observatory. In addition, the Committee on Astronomy and Astrophysics Panel on Ground-based Optical and Infrared Astronomy released its report, and the Task Group on Priorities in Space Research issued its second and final report. Five short reports were also prepared and released during 1995. They addressed such diverse topics as reflight of shuttle-borne synthetic aperture radars, the role of NASA centers and center scientists in scientific research, guidelines for establishment of NASA research institutes, and clarification of findings of the microgravity research opportunities report and of the Future of Space Science Committee's management study

    A Climate Change Vulnerability Assessment among Small Farmers: A Case Study in Western Honduras

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    Climate change is now affecting every known society. Small farmers in Low Income Countries (LICs) are especially vulnerable to climate change patterns because they depend heavily on rain, seasonality patterns, and known temperature ranges. To help build climate change resilient communities among rural farmers, the first step is to understand the impact of climate change on the population. This dissertation aims to use information and communication technology (ICT) to assess climate change vulnerabilities among rural farmers. To achieve this overall goal, this dissertation first proposes a comprehensive Climate Change Vulnerability Assessment Framework (CCVAF) that integrates both community level and individual household level indicators. The CCVAF was instantiated into a GIS-based web application named THRIVE for different decision makers to better assess how climate change is affecting rural farmers in Western Honduras. Qualitative evaluation of the THRIVE showed that it is an innovative and useful tool. The CCVAF and its instantiation provides an important initial step towards building climate change resilience among rural farmers. It is the first attempt to provide a comprehensive set of the indicators with related measurements and data sources for climate change vulnerability assessment. The framework thus contributes to the knowledge base of the climate change vulnerability assessment. It also contributes to the design science literature by providing guidelines to design a class of climate change vulnerability assessment solutions. To the best of our knowledge, the CCVAF is the first generalizable artifact that can be used to build a group of ICT-based climate change vulnerability assessment solutions. Another knowledge contribution of this dissertation is its reproducibility by making the input and output data available to the research and practitioner community through a GeoHub. For practical contributions, the framework can be easily used by researchers and practitioners to consistently design a vulnerability assessment tool, starting with the set of indicators organized by the three-level determinants, and following specific spatial data analysis and models. Such an ICT-based tool adds practical values to tackle climate change challenges

    Sensor management for enhanced catalogue maintenance of resident space objects

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