S. R. Paradise

Development of an aerosol opacity retrieval algorithm for use with multi-angle land surface images

In 1998, the Multi-angle Imaging SpectroRadiometer (MISR) will fly aboard the EOS-AM1 spacecraft. MISR will enable unique methods for retrieving the properties of atmospheric aerosols, by providing global imagery of the Earth at nine viewing angles in four visible and near-IR spectral bands. As part of the MISR algorithm development, theoretical methods of analyzing multi-angle, multispectral data are being tested using images acquired by the airborne Advanced Solid-State Array Spectroradiometer (ASAS). The authors derive a method to be used over land surfaces for retrieving the change in opacity between spectral bands, which can then be used in conjunction with an aerosol model to derive a bound on absolute opacity. They demonstrate the method using ASAS data.<<ETX>>

The aerosol measurement and processing system (AMAPS)

As the collection of Earth science datasets continues to grow, so too grows the challenge in the ability to collect, interpret, assimilate, compare, and combine them. Stores of data, already enormous, continue to amass. New instruments are built that introduce differences in measurements and retrieval algorithms from previous ones. Data are rarely collocated either spatially or temporally, and rarely represent equivalent quantities even for similarly named parameters. Uncertainties must be understood and accounted for. Formats differ. In the realm of diverse data sources, the analyst each time must become an expert in the data from each source, and that expertise is disseminated in the form of publications (if at all), but analysis tools are not, and must be continually redeveloped. AMAPS addresses each of these areas in a way that provides a breakthrough in the analyst’s ability to efficiently and effectively make use of the vast wealth of data that continues to accumulate. AMAPS is targeted to aerosol data acquisition and analysis. Data from disparate aerosol sources, including the Multi-angle Imaging SpectroRadiometer (MISR), the Moderate Resolution Imaging Spectrometer (MODIS), and the AErosol RObotic NETwork (AERONET), are efficiently retrieved and transformed behind the scenes to a common format via SciFlo. Analysis algorithms for collocation and comparison between sources are generalized so that researchers have access to a common set of tools applied consistently to each data source. AMAPS has established a successful track record in supporting scientific research.

The aerosol measurement and processing system and applications to African studies

The Aerosol Measurement and Processing System (AMAPS) simplifies access to large satellite and ground-based aerosol data sets by allowing computationally expensive and I/O intensive operations to be performed by the systems that host the data sources and then returning the condensed results in a simple common format. This significantly reduces much of the overhead associated with data retrieval and storage, particularly for large and intrinsically complex data sets. AMAPS further facilitates data analysis by providing generalized algorithms that are consistently applied to different data sources in a manner transparent to the user. For example, common geolocation and collocation algorithms are available for multiple instruments, along with interpolation of geophysical retrievals, such as aerosol optical thickness (AOT), to common wavelengths. AMAPS also includes a common set of tools for data reduction, analysis, and plotting. In this paper, we describe the AMAPS system and demonstrate the application of the tool for aerosol studies tailored to the African continent and surrounding areas.

Status of the Multi-angle Imaging SpectroRadiometer instrument for EOS-AM1 and its application to remote sensing of aerosols

The Multi-angle Imaging SpectroRadiometer (MISR) instrument is currently under development at JPL for the AM1 spacecraft in the Earth Observing System (EOS) series. MISR consists of nine pushbroom cameras, and will provide global coverage in four visible/near-infrared spectral bands. This measurement strategy provides systematic multi-angle imagery of the Earth for studies of aerosols, surface radiation, and clouds. An on-board calibrator consisting of deployable solar diffusers and a set of stable photodiodes provides a high-accuracy detector-based calibration. In this paper the authors report on the progress of the instrument fabrication and testing and focus on the application of MISRs unique observational strategy to studies of tropospheric aerosols.