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We present a general methodology and first results of total column trace gas retrievals from hyperspectral infrared observations. More specifically, we made use of a physical scheme to retrieve methane (CH4) profiles from atmospheric infrared sounder (AIRS) measurements. The method firstly required a forward calculation that maps the a priori state vector into measurement space, and for this we used...
The paper firstly points out the defect of conventional temperature and emissivity separation algorithms when dealing with hyperspectral FTIR data: the conventional temperature and emissivity algorithms can not reproduce correct emissivity value when the difference of ground-leaving radiance and object's blackbody radiation at its true temperature and the instrument random noise are on the same order,...
Analysis of L-band polarimetric SAR data has not been extensively carried out for undulating, heterogeneous and fragmented landscapes, where classification can become quite challenging. This paper reports results of a study on the pixel-by- pixel unsupervised classification of very-high resolution polarimetric images by self-organizing neural networks.
Airborne polarimetric and interferometric synthetic aperture radar (Pi-SAR) observation, conducted in the southern Sea of Okhotsk in February 2005, provided the opportunity to validate the retrieval of ice thickness distribution. In conjunction with the airborne SAR observation, in-situ ice thickness and ice- surface roughness measurements were carried out in the same area with ship-borne electromagnetic...
The NASA-developed Earth Observing System (EOS) Clearinghouse (ECHO) is a spatial and temporal metadata registry that enables the science community to more easily use and exchange NASA's data and services. Currently, ECHO contains metadata for over 2,149 data collections comprising 56 million individual data granules and 14 million browse images. ECHO stores metadata from a variety of science disciplines...
The global land ice measurement from space (GLIMS) project is a cooperative effort of over sixty institutions world-wide with the goal of inventorying a majority of the world's estimated 160000 glaciers. Data sent from regional center analysts to the GLIMS team at the national snow and ice data center (NSIDC) in Boulder, Colorado are inserted into a geospatial database. The GLIMS Glacier Database...
The Iroise Sea is a shallow sea, located on the North West European Shelf close to Western Brittany (France) and North of the Bay of Biscay. Due to strong gradients in the bathymetry close to the coast and strong local winds, tidal currents can reach up to 3.5 m/s during spring tide and induce a strong vertical mixing along the coast. During summer, solar radiation and thus warming of the sea surface,...
An atmospheric correction algorithm for ocean color data with multiple viewing and polarization information is proposed. The correction is based on using the directional and polarized data for 865 nm and 665 nm to estimate the properties of aerosols over the ocean. The aerosol models used in atmospheric correction consist of bimodal size distributions. And, a best-fit optical thickness is grossly...
This paper gives an overview of the ECOCLIMAP-II database, which is a new surface parameters global dataset at a 1 km resolution. The aim of this database is to initialize soil-vegetation-atmosphere-transfer (SVAT) schemes in meteorological and climate modeling. The overall objective of this paper is then to provide elements of the method used to derive surface parameters at 1 km resolution departing...
National Institute of Information and Communications Technology (NICT) is developing 9.25 MHz ocean radar for measuring the sea surface currents and ocean waves on the offshore. This study clarifies the validity and accuracy of observing ocean waves, when the typhoon passed through the observation area, with 9.25 MHz ocean radar. In addition, we compare inversion algorithms for 9.25 MHz ocean radar...
As a long term objective we would like to define the required conditions to detect oil spills, using high frequency surface wave radar (HFSWR). Assuming that the presence of oil spills on the sea surface modifies the surface tension which in turn affects the dynamics of the sea, we would like to determine the minimal surface tension which makes this phenomenon observable on a Doppler spectrum. For...
Marine dark features in SAR imagery related to oil spills, biogenic look-alikes and low wind areas are analyzed by means of the wavelet polarimetric signature (WASP) tool. The WASP encapsulates in a graph the dependency of the wavelet variance on dyadic scale and polarization state. Experiments on SIR-C/X-SAR C-band data showed the effectiveness of this analysis in characterizing textural features...
Based on meteorological and hydrological data collected from 1961 to 2004,NOAA/AVHRR NDVI data with 8times8 km spatial resolution from 1982 to 2003, climate change and its ecosystem effect are analyzed in the upper yellow river in this paper. The results showed that the change trend of temperature in the upper yellow river was consistent with global warming, and the increasing rate of annual mean...
A new type of remote sensing instrument based upon the Fabry-Perot interferometric technique has been developed at NASA's Goddard Space Flight Center. Fabry-Perot interferometry (FPI) is a well known, powerful spectroscopic technique. One of its many applications is to be used to measure greenhouse gases as well as harmful species in the atmosphere. With this technique, absorption of particular species...
Monitoring changes in the vegetation cover during the intercrop season is of a special interest in intensive agricultural regions. The presence of bare soils leads to detrimental environmental effects such as soil erosion or water quality degradation. To identify and monitor winter land cover at a regional scale in the Brittany region in France, data from the moderate resolution imaging spectroradiometer...
Geostationary Infrared Sounding missions offer good temporal coverage, however due to the large distance to the observed Earth targets the effect of diffraction is increased compared to sounding from a low Earth orbit (LEO). Because of the wave-length dependence of diffraction, the spectral channels do not sample the same volume of air, as in general assumed by retrieval algorithms for LEO IR (Infrared)...
Fine resolution spotlight synthetic aperture radar (SAR) imagery collected on a circular flight path is used to investigate the variation in ship detection performance with respect to three fundamental radar parameters: the transmit/receive polarisation combination, the incidence angle and the azimuth angle. The polarisation combinations examined are HH, HV, VV, RR and cross-slant 45deg. Three different...
The ONERA RAMSES system is a flexible SAR system in constant evolution, developed mainly as a test bench for new technologies and to provide specific data for TDRI (Target Detection, Recognition and Identification) algorithm evaluation. It is flown on a Transall C160 platform operated by the CEV (Centre d'Essais en Vol). This paper gives an overview of the latest upgrading to acquire large data set...
Image understanding and retrieval for metric SAR data needs to be tackled by specific algorithms in order to exploit the specific metric scale scene characteristics and the typical sensor phenomenology. A composite approach is developed to this end. Extraction, characterization and simplification/grouping algorithms are employed together with super-resolution for isolated bright scatterers, scatterer...
Quantification of vegetation cover can facilitate an improved understanding of ecosystem function and crop yield. Current methods of cover measurement can be divided into field surveys and remote sensing, with their associated advantages and disadvantages. Digital camera images provide high temporal and spatial resolution at low cost than satellite images. A method to accurately and conveniently estimate...
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