Search results for "Intercomparison"
showing 5 items of 15 documents
Global distributions of diazotrophs Gamma-A nifH genes abundance - Depth integrated values computed from a collection of source datasets - Contributi…
2013
The MAREDAT atlas covers 11 types of plankton, ranging in size from bacteria to jellyfish. Together, these plankton groups determine the health and productivity of the global ocean and play a vital role in the global carbon cycle. Working within a uniform and consistent spatial and depth grid (map) of the global ocean, the researchers compiled thousands and tens of thousands of data points to identify regions of plankton abundance and scarcity as well as areas of data abundance and scarcity. At many of the grid points, the MAREDAT team accomplished the difficult conversion from abundance (numbers of organisms) to biomass (carbon mass of organisms). The MAREDAT atlas provides an unprecedente…
Comparison of the strain field of abdominal aortic aneurysm measured by magnetic resonance imaging and stereovision: a feasibility study for predicti…
2015
International audience; The prediction of the risk of rupture of abdominal aortic aneurysm (AAA) is a complex problem. Currently the criteria to predict rupture of abdominal aortic aneurysms are aneurysm diameter and growth rates. It is generally believed that study of the wall strain distribution could be helpful to find a better decision criterion for surgery of aortic aneurysms before their rupture. The wall strain distribution depends on many biological and biomechanical factors such as elastic properties of the aorta, turbulent blood flow, anatomy of the aorta, presence of thrombus or not and so on. Recently, numerical simulations to estimate rupture-potential have received many attent…
Intercomparison of SO2 camera systems for imaging volcanic gas plumes
2015
Abstract SO 2 camera systems are increasingly being used to image volcanic gas plumes. The ability to derive SO 2 emission rates directly from the acquired imagery at high time resolution allows volcanic process studies that incorporate other high time-resolution datasets. Though the general principles behind the SO 2 camera have remained the same for a number of years, recent advances in CCD technology and an improved understanding of the physics behind the measurements have driven a continuous evolution of the camera systems. Here we present an intercomparison of seven different SO 2 cameras. In the first part of the experiment, the various technical designs are compared and the advantage…
Radar-rain gauges intercomparison for the estimation of high resolution rainfall.
2015
An accurate rainfall estimation is essential for many applications like precision viticulture. Rainfall is most of the time estimated by two methods:radar and rain gauges. High resolution rain gauges network Hydravitis was installed in 2014. Data coming from radar,composite product and the network was extracted for the 2014 3 to 4 November event. Data from the network were kriged tocompare with the other products. Results show that PANTHERE radar image well reproduces the spatial variability ofrainfall but underestimates rainfall amounts over a 4 mm/h intensité. Composite product ANTILOPE gives a goodvisualization of spatial variability and intensity of rainfall. Expectations of viticulture…
On Line Validation Exercise (OLIVE): A Web Based Service for the Validation of Medium Resolution Land Products. Application to FAPAR Products
2014
International audience; The OLIVE (On Line Interactive Validation Exercise) platform is dedicated to the validation of global biophysical products such as LAI (Leaf Area Index) and FAPAR (Fraction of Absorbed Photosynthetically Active Radiation). It was developed under the framework of the CEOS (Committee on Earth Observation Satellites) Land Product Validation (LPV) sub-group. OLIVE has three main objectives: (i) to provide a consistent and centralized information on the definition of the biophysical variables, as well as a description of the main available products and their performances (ii) to provide transparency and traceability by an online validation procedure compliant with the CEO…