Studies

VisioTerra carries out studies on various subjects ranging from the evaluation of products from data producers (mainly space agencies) to more thematic subjects such as studies of the evolution of land use, deforestation, extension of urban areas, analysis in structural geology and hydrogeology, environmental impact, estimation of pollution...

Product evaluation allows space agencies to assess the quality of a product with respect to external references, to compare products between them and to quantify the suitability for use for different applications. The study carried out for ESA consisted of evaluating the accuracy of the heights provided by the SRTM, ASTER GDEM, ALOS World 3D and Copernicus DEMs DTMs compared to the ICESat LiDAR data. The DTMs were compared to each other by calculating the difference between two DTMs on the fly. Their usability was measured by comparing the orthorectification results from the same scene but using two different DTMs. The study carried out for the CNES allowed to verify the access to several scenes among the 150,000 produced, their processing on the fly, the results of the pseudo "natural colors" color composition and to produce a gallery of hyperlooks of SPOT-123, SPOT-4 and SPOT-5 scenes.


Thematic studies are commissioned by United Nations agencies or NGOs. The aim is to establish a baseline at a given time or to analyze the evolution of the land cover over time by producing maps at regular intervals. In both cases, the user provides the nomenclature of the desired classes.


References

Climate change

VisioTerra

Detection, classification and analysis of oil slicks observed by the ASAR radar instrument in WSM mode onboard Envisat between 2002 and 2012. Oil slicks are classified according to whether they are of natural origin (oil seepages) or anthropogenic (oil spills from platforms or deballasting of ships).
 

10 years of oil in the Gulf of Guinea

VisioTerra

Analysis of the three Copernicus Digital Elevation Models (DEMs) (EEA-10, GLO-30 and GLO-90). Comparison of GLO-30 with the other global DEMs SRTM, ASTER GDEM and ALOS World 3D. Altimeter accuracy computed from LiDAR ICESat-1, ICESat-2 ("Terrain only" and "Terrain with canopy") and GEDI ("Lowest mode" and "Highest return") data. Statistical measure of the influence of land cover.

Estimation of the quality of Copernicus DEMs

ESA

Monitoring of land cover changes over the last 20 years (2000, 2005, 2010, 2015 and 2019) using Landsat-7, Landsat-8 and Sentinel-2 data. Detection of illegal mining sites.

Study of deforestation and mining activity in the territory of Bafwasende (DRC)

Tropenbos International

Analysis of forest degradation since 2000 in favour of cocoa agroforestry in the forest reserves (excluding admitted farms) of Tano-Ofin, Sui-River and Krokosua using radar and optical images.

Study of deforestation in three Forest Reserves in Ghana

Tropenbos International

Production of land use maps of the three protected areas ZC Djona, ZC Mekrou and PN W-Benin and their periphery from satellite data since 1998.

Study of the dynamics of land use in the hunting zones (ZC) and national park (PN) in Benin

APN Benin

Integration of the free SPOT-123/4/5 image catalog in VtWeb. Development of pseudo "natural colors" rendering functions. Production of a gallery of views.

Galerie SPOT World Heritage

CNES

Supply and processing of images (radar and optical) on the Tindouf Basin (Algeria). Production of geological photo-interpretation maps.

Geological analysis in the Tindouf Basin

Beicip Franlab / SONATRACH

Integrated Strategic Environmental Assessment (ISEA) for the development of the port of San-Pedro (Ivory Coast). Rainfall study, flood simulation, land use spatio-mapping, coastline evolution study, constitution of the dedicated GIS.

ISEA San-Pedro

UNEP

Sentinel-2 data were used to calculate differences in vegetation indices before and after Hurricane Matthew occurred on October 4, 2016.

Assessment of vegetation losses after Hurricane Matthew

UNEP

Investigation of the volume and accessibility of ESA’s major EO archives. Developed a prototype to access and process -DHuS Sentinel-1, -Envisat ASAR/MERIS, -Landsat-5/7 TM/ETM+ collections on the fly.

Study « Live-link to ESA Big Data »

ESA

Field survey and production of a report for the capacity building of the Geomatics Laboratory of the regional school ERAIFT in Kinshasa, DRC.

Capacity Building

ERAIFT

Study of the potential of satellite data for environmental monitoring in very cold areas.

Cryosat over the Arctic

TOTAL

Development and qualification of methods for recovering the optical signature of hydrocarbons from slicks detected by radar.

Radar / optical coupling

TOTAL

Rwanda Environment Management Authority (REMA) - Supervision of the RBIS project from the tender to the development of the software, the organization of the data and the different trainings.

REMA Biodiversity Information System (RBIS)

REMA / World Bank

Compilation and accurate geocoding of optical and radar data (satellite and aerial views) acquired over the last 35 years. Photo-interpretation of the coastline and development of tools to quantify erosion/accretion.

Coastal erosion of the Mandji peninsula

TOTAL

Generic description of missions and instruments using SensorML to support the Calibration / Validation activities of the CEOS group.

CAL/VAL Portal

ESA / Brockmann Consult

Improvement and correction of the manual by introducing user questions (FAQ), a description of applications and level 3 products.

MERIS Product Manual

ESA-ESRIN

This manual accurately describes the shooting geometry, algorithms and programs to orthorectify MERIS Level 1B images from auxiliary elevation data or external DTM(s).

MERIS Geometry Manual

ESA-ESTEC



All our references