8,215 research outputs found

    Earth radiation budget measurements from satellites and their interpretation for climate modeling and studies

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    The annual and seasonal averaged Earth atmosphere radiation budgets derived from the most complete set of satellite observations available are presented. The budgets were derived from a composite of 48 monthly mean radiation budget maps. Annually and seasonally averaged radiation budgets are presented as global averages and zonal averages. The geographic distribution of the various radiation budget quantities is described. The annual cycle of the radiation budget was analyzed and the annual variability of net flux was shown to be largely dominated by the regular semi and annual cycles forced by external Earth-Sun geometry variations. Radiative transfer calculations were compared to the observed budget quantities and surface budgets were additionally computed with particular emphasis on discrepancies that exist between the present computations and previous surface budget estimates

    Radiation measurements from polar and geosynchronous satellites

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    Nimbus 5 satellite data and its use to study climate and develop climate model experiments are examined. Data cover: (1) physical basis for understanding long range and climate monitoring and prediction problem, (2) delineating energy loss to space between contributions from land, ocean, and atmosphere, (3) temporal and spatial distribution in earth's energy budget and its variations due to global cloud fields, and (4) studies of the frequency of occurrence of precipitation over ocean areas

    Stratospheric measurement requirements and satellite-borne remote sensing capabilities

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    The capabilities of specific NASA remote sensing systems to provide appropriate measurements of stratospheric parameters for potential user needs were assessed. This was used to evaluate the capabilities of the remote sensing systems to perform global monitoring of the stratosphere. The following conclusions were reached: (1) The performance of current remote stratospheric sensors, in some cases, compares quite well with identified measurement requirements. Their ability to measure other species has not been demonstrated. (2) None of the current, in-situ methods have the capability to satisfy the requirements for global monitoring and the temporal constraints derived from the users needs portion of the study. (3) Existing, non-remote techniques will continue to play an important role in stratospheric investigations for both corroboration of remotely collected data and in the evolutionary development of future remote sensors

    Thermal infrared remote sensing of surface features for renewable resource applications

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    The subjects of infrared remote sensing of surface features for renewable resource applications is reviewed with respect to the basic physical concepts involved at the Earth's surface and up through the atmosphere, as well as the historical development of satellite systems which produce such data at increasingly greater spatial resolution. With this general background in hand, the growth of a variety of specific renewable resource applications using the developing thermal infrared technology are discussed, including data from HCMM investigators. Recommendations are made for continued growth in this field of applications

    Environmental assessment overview

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    The assessment program has as its objectives: to identify the environmental issues associated with the SPS Reference System; to prepare a preliminary assessment based on existing data; to suggest mitigating strategies and provide environmental data and guidance to other components of the program as required; and to plan long-range research to reduce the uncertainty in the preliminary assessment. The key environmental issues associated with the satellite power system are discussed and include human health and safety, ecosystems, climate, and interaction with electromagnetic systems

    The Role of N2 as a Geo-Biosignature for the Detection and Characterization of Earth-like Habitats

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    Since the Archean, N2 has been a major atmospheric constituent in Earth's atmosphere. Nitrogen is an essential element in the building blocks of life, therefore the geobiological nitrogen cycle is a fundamental factor in the long term evolution of both Earth and Earth-like exoplanets. We discuss the development of the Earth's N2 atmosphere since the planet's formation and its relation with the geobiological cycle. Then we suggest atmospheric evolution scenarios and their possible interaction with life forms: firstly, for a stagnant-lid anoxic world, secondly for a tectonically active anoxic world, and thirdly for an oxidized tectonically active world. Furthermore, we discuss a possible demise of present Earth's biosphere and its effects on the atmosphere. Since life forms are the most efficient means for recycling deposited nitrogen back into the atmosphere nowadays, they sustain its surface partial pressure at high levels. Also, the simultaneous presence of significant N2 and O2 is chemically incompatible in an atmosphere over geological timescales. Thus, we argue that an N2-dominated atmosphere in combination with O2 on Earth-like planets within circumstellar habitable zones can be considered as a geo-biosignature. Terrestrial planets with such atmospheres will have an operating tectonic regime connected with an aerobe biosphere, whereas other scenarios in most cases end up with a CO2-dominated atmosphere. We conclude with implications for the search for life on Earth-like exoplanets inside the habitable zones of M to K-stars

    Upper Atmosphere Research Satellite (UARS): A program to study global ozone change

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    A general overview of NASA's Upper Atmosphere Research Satellite (UARS) program is presented in a broad based informational publication. The UARS will be responsible for carrying out the first systematic, comprehensive study of the stratosphere and will furnish important new data on the mesosphere and thermosphere. The UARS mission objectives are to provide an increased understanding of energy input into the upper atmosphere; global photochemistry of the upper atmosphere; dynamics of the upper atmosphere; coupling among these processes; and coupling between the upper and lower atmosphere. These mission objectives are briefly described along with the UARS on-board instrumentation and related data management systems

    Glossary of International Climate Policy Terms

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    Environmental Economics and Policy,

    Correlated k-distribution method for radiative transfer in climate models: Application to effect of cirrus clouds on climate

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    A radiative transfer method appropriate for use in simple climate models and three dimensional global climate models was developed. It is fully interactive with climate changes, such as in the temperature-pressure profile, cloud distribution, and atmospheric composition, and it is accurate throughout the troposphere and stratosphere. The vertical inhomogeneity of the atmosphere is accounted for by assuming a correlation of gaseous k-distributions of different pressures and temperatures. Line-by-line calculations are made to demonstrate that The method is remarkably accurate. The method is then used in a one-dimensional radiative-convective climate model to study the effect of cirrus clouds on surface temperature. It is shown that an increase in cirrus cloud cover can cause a significant warming of the troposphere and the Earth's surface, by the mechanism of an enhanced green-house effect. The dependence of this phenomenon on cloud optical thickness, altitude, and latitude is investigated
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