A5015541626- Marine and coastal ecosystems
- Atmospheric and Environmental Gas Dynamics
- Water Quality Monitoring and Analysis
- Atmospheric Ozone and Climate
- Geophysics and Gravity Measurements
- Atmospheric aerosols and clouds
- Oceanographic and Atmospheric Processes
- Meteorological Phenomena and Simulations
- Climate variability and models
- Air Quality Monitoring and Forecasting
- Ionosphere and magnetosphere dynamics
- Arctic and Antarctic ice dynamics
- Oil Spill Detection and Mitigation
- Water Quality Monitoring Technologies
- Methane Hydrates and Related Phenomena
- Climate change and permafrost
- Advanced Computational Techniques and Applications
- Calibration and Measurement Techniques
- Cryospheric studies and observations
- Echinoderm biology and ecology
- Coral and Marine Ecosystems Studies
- Atmospheric chemistry and aerosols
- Soil Moisture and Remote Sensing
- Earthquake Detection and Analysis
- Remote Sensing and LiDAR Applications
Inform (Germany)
2011-2024
Freie Universität Berlin
1989-2003
Sorbonne Université
2000
Centre National de la Recherche Scientifique
2000
University of Maine
1975
Variations in the spectral scattering coefficient of marine particles [ b p (λ)] were measured at 241 locations oceanic (case 1) and coastal 2) waters around Europe. The 555 nm normalized to dry mass m (555)] was, on average, 1.0 0.5 2 g ‐1 case 1 waters, respectively. Spectral variations (λ) were, small all investigated waters. To understand observed particle scattering, we performed calculations based Mie theory with various values for slope Junge‐type size distribution, refractive index,...
[1] A method to derive two-layer cloud properties from concurrent visible, near-infrared, and infrared observations is described. It a modification of single-layer scheme applied Spinning Enhanced Visible Infrared Imager (SEVIRI) validated against coincident A-Train data, principally evaluate the accuracy characterize top pressure (CTP) estimates. CTP values obtained multilayer clouds are significant overestimates upper layer value. The effect usually larger than that on IR-only retrievals...
Abstract. The Global Energy and Water cycle Exchanges (GEWEX) Data Assessments Panel (GDAP) initiated the GEWEX Vapor Assessment (G-VAP), which has main objectives to quantify current state of art in water vapour products being constructed for climate applications support selection process suitable by GDAP its production globally consistent energy products. During construction G-VAP data archive, freely available mature satellite reanalysis records with a minimum temporal coverage 10 years...
Abstract. We use the CloudSat 2006–2016 data record to estimate snowfall over Greenland Ice Sheet (GrIS). first evaluate retrievals with respect remaining ground-clutter issues. Comparing observations GrIS topography (obtained from airborne altimetry measurements during IceBridge) we find that at edges of spurious high-snowfall caused by ground clutter occasionally affect operational product. After correcting for this effect, height lowest valid observation is about 1200 m above local as...
To date, a large variety of water vapour data records from satellite and reanalysis are available. It is key to understand the quality uncertainty these in order fully exploit avoid being employed incorrectly or misinterpreted. Therefore, it important inform users on accuracy limitations based consistent inter-comparisons carried out framework international assessments. Addressing this challenge major objective Global Water Energy Exchanges (GEWEX) vapor assessment (G-VAP) which was...
A model developed recently by Loisel and Stramski [Appl. Opt. 39, 3001-3011 (2000)] for estimating the spectral absorption a(lambda), scattering b(lambda), backscattering b(b)(lambda) coefficients in upper ocean from irradiance reflectance just beneath sea surface R(lambda, z = 0(-)) diffuse attenuation of downwelling within layer ?K(d)(lambda)?(1) is compared with measurements. Field data this comparison were collected different areas including off-shore near-shore waters off southern...
A system was designed for the continuous surface monitoring of hydrological, bio‐optical, and biogeochemical properties in vicinity Almeria‐Oran jet‐front (Northwestern Mediterranean Sea). This included a thermosalinograph, fluorometer, an optical particle counter, absorbance‐attenuance meter (AC9), allowing estimation absorption [ (λ), (m −1 )] scattering b coefficients at nine wavelengths. More than 500 multivariate records were acquired over transect crossing three times encompassing...
In the present paper, we report on a method to retrieve pigment concentration in Case I waters from ocean color. The is derived radiative transfer (RT) simulations and subsequent application of artificial neural network (ANN) techniques. Information absorption total scattering pure seawater, colored dissolved organic matter, marine particles are mostly taken published measurements or parameterizations. Additionally, new model relating backscattering wavelength introduced. such defined...
A robust empirical algorithm to determine the diffuse attenuation coefficient K d at a wavelength of 490 nm ( ) from spectral remote sensing reflectance has been derived NOMAD data set and tested against COASTLOOC set. Together, both sets contain more than 3,800 observations concomitantly acquired bio‐optical parameters in waters ranging very clear turbid, which about 2,300 have used this study. The proposed follows power law form = 10^( 0 + 1 x 2 3 4 , where is common logarithm either two...
The Arctic is directly impacted by climate change. increase in air temperature drives the thawing of permafrost and an coastal erosion river discharge. This leads to a greater input sediment organic matter into waters, which substantially impacts ecosystems, subsistence economy local population, because transformation greenhouse gases. Yet, patterns dispersal nearshore zone are not well known, ships do often reach shallow waters satellite remote sensing traditionally focused on less dynamic...
Remotely sensed data inherently contain noise. The development of inverse modelling methods with a low sensitivity to noise is in demand for the estimation geophysical variables from remotely data. Active Learning Method (ALM) well known have For first time, ALM was utilized inversion radiative transfer calculations aim estimating chlorophyll (Chl a), coloured dissolved organic matter (CDOM), and suspended particulate (SPM) Caspian Sea using MERIS (MEdium Resolution Imaging Spectrometer)...
Abstract. Validating the accuracy and long-term stability of terrestrial satellite data products necessitates a network reference sites. This paper documents global database more than 2000 sites globally which have been characterized in terms their spatial heterogeneity. The work was motivated by need for potential validation geostationary surface albedo products, but resulting is useful also other applications. (SAVS 1.0) publicly available through EUMETSAT website...
Abstract. The Global Energy and Water cycle Exchanges (GEWEX) Data Assessments Panel (GDAP) initiated the GEWEX Vapor Assessment (G-VAP), which has main objectives to quantify current state of art in water vapour products being constructed for climate applications support selection process suitable by GDAP its production globally consistent energy products. During construction G-VAP data archive, freely available mature satellite reanalysis records with a minimum temporal coverage 10 years...
Abstract. Since 2011, the Global Energy and Water cycle Exchanges (GEWEX) Vapor Assessment (G-VAP) has provided performance analyses for state-of-the-art reanalysis satellite water vapour products to GEWEX Data Analysis Panel (GDAP) user community in general. A significant component of work undertaken by G-VAP is characterise quality uncertainty these records (i) ensure full exploitation (ii) avoid incorrect use or interpretation results. This study presents results from second phase G-VAP,...
Abstract. Coastal Surveillance Through Observation of Ocean Color (COASTℓOOC) oceanographic expeditions were conducted in 1997 and 1998 to examine the relationship between optical properties seawater related biological chemical across coastal open-ocean gradient various European seas. A total 379 stations visited along coasts Gulf Lion Mediterranean Sea (n=61), Adriatic (n=39), Baltic (n=57), North (n=99), English Channel (n=85), Atlantic (n=38). Particular emphasis was placed on collection...
Abstract. Surface albedo has been identified as an important parameter for understanding and quantifying the Earth's radiation budget. EUMETSAT generated Meteosat Albedo (MSA) Climate Data Record (CDR) currently comprising up to 24 years (1982–2006) of continuous surface coverage large areas Earth. This CDR created within Sustained, Coordinated Processing Environmental Satellite Monitoring (SCOPE-CM) framework. The long-term consistency MSA is high meets Global Observing System (GCOS)...
Sun glint, i.e., direct solar radiation reflected from a water surface, negatively affects the accuracy of ocean color retrieval schemes if entering field-of-view observing instrument. Herein, simple and robust method to quantify sun glint contribution top-of-atmosphere reflectances in visible near-infrared is proposed, exploiting concomitant observations glint’s morphology shortwave infrared. The method, termed Glint Removal through Contrast Minimization (GRCM), requires high spatial...
Due to the noise that is present in remote sensing data, a robust method retrieve information needed. In this study, active learning (ALM) applied spectral reflectance data in‐water pigment. The heart of ALM fuzzy interpolation called ink drop spread (IDS). Three datasets (SeaBAM, synthetic and NOMAD) are used for evaluation selected approach. Comparison with ocean colour 4 (OC4) algorithm artificial neural network (ANN) demonstrated robustness approach retrieval constituents from data....
Abstract. Since 2011 the Global Energy and Water cycle Exchanges (GEWEX) Vapor Assessment (G-VAP) has provided performance analyses for state-of-the-art reanalysis satellite water vapour products to GEWEX Data Analysis Panel (GDAP) user community in general. A significant component of work undertaken by G-VAP is characterise quality uncertainty these records to; i) ensure full exploitation ii) avoid incorrect use or interpretation results. This study presents results from second phase G-VAP,...
After the successful launch of Medium Resolution Imaging Spectrometer (MERIS) on board European Space Agency (ESA) Environmental Satellite (ENVISAT) March 1st 2002, first MERIS data are available for validation purposes. The primary goal mission is to measure color sea with respect oceanic biology and marine water quality. We present an atmospheric correction algorithm case-I waters based inverse modeling radiative transfer calculations by artificial neural networks. proposed scheme accounts...
Abstract. The microwave radiometers (MWRs) on board the European Remote Sensing Satellites 1 and 2 (ERS-1 ERS-2) Envisat provide a continuous time series of brightness temperature observations between 1991 2012. Here we report new total column water vapour (TCWV) wet tropospheric correction (WTC) dataset that builds this series. We use one-dimensional variational approach to derive TCWV from MWR ERA-Interim background information. A particular focus study lies intercalibration three...