An integrated web-based system for observatories networks management and monitoring

View the Project on GitHub IPGP/webobs

WebObs is an integrated web-based system for data monitoring and networks management. Seismological and volcanological observatories have common needs and often common practical problems for multi disciplinary data monitoring applications. In fact, access to integrated data in real-time and estimation of uncertainties are keys for an efficient interpretation, but instruments variety, heterogeneity of data sampling and acquisition systems lead to difficulties that may hinder crisis management. In the Guadeloupe observatory, we have developed in the last 15 years an operational system that attempts to answer the questions in the context of a pluri-instrumental observatory. Based on a single computer server, open source scripts (with few free binaries) and a Web interface, the system proposes:

WebObs is presently fully functional and used in a dozen observatories (see the related publications) and was awarded in 2022, but the documentation for end users is still incomplete and there is no tutorial. We hope to shortly finish the main user’s manual. If you are in a hurry, please contact the project coordinator and we will be happy to help you to install it. WebObs is fully described in the following paper (please cite this one if you publish something using WebObs):

Beauducel F., D. Lafon, X. Béguin, J.-M. Saurel, A. Bosson, D. Mallarino, P. Boissier, C. Brunet, A. Lemarchand, C. Anténor-Habazac, A. Nercessian, A. A. Fahmi (2020). WebObs: The volcano observatories missing link between research and real-time monitoring, Frontiers in Earth Sciences, doi:10.3389/feart.2020.00048.

Download the latest release

For install and update, please follow instructions below.

IMPORTANT: when upgrading from a previous version, please read carefully the information at the end of the procedure: some updates may require changes in your configuration files.

Source code, comments and issues are available at the project repository github.com/IPGP/webobs.

Installation / upgrading

To run WebObs you need to install the package which contains a setup script that will set all configuration files. Installing WebObs is not a classical compilation from sources with ‘make’. A part of it requires the free Matlab runtime library because package contains some compiled binaries for optimization purpose.

A) Installing WebObs <version> from its WebObs-<version>.tgz

You create/choose your WebObs directory within which you will execute the setup process. We suggest /opt/webobs (default). This directory will contain both WebObs code and WebObs data, and will be the DocumentRoot of the WebObs Apache’s Virtual Host.

setup will prompt you for a Linux WebObs userid (aka WebObs Owner) that it will create. The WebObs userid’s group will also be added to Apache’s user. See the WebObs user manual if you need to create your own WebObs owner.

The system-wide /etc/webobs.d symbolic link will identify your WebObs ‘active’ (production) installation.

WebObs comes with pre-defined configuration files and pre-defined data objects as a starting point and for demonstration purposes.


Graph processes need Matlab compiler runtime 2011b (available above). Download the installer adapted to your architecture in the WebObs directory, the setup will install it during the C) procedure. Or, place it in any local directory then run:

unzip MCR_<version>_installer.zip
sudo ./install -mode silent

A number of programs and Perl modules are needed to run webobs. During the C) installation procedure, setup will list the missing dependencies that must be installed. Under Debian/Ubuntu, you might install them using the following packages:

sudo apt install apache2 apache2-utils sqlite3 imagemagick pngquant qrencode jq mutt xvfb \
   curl gawk graphviz net-tools libdatetime-perl libdatetime-format-strptime-perl libdate-calc-perl \
   libcgi-session-perl libdbd-sqlite3-perl libgraphviz-perl libimage-info-perl \
   libtext-multimarkdown-perl libswitch-perl libintl-perl libncurses5 \
   wkhtmltopdf poppler-utils libjson-perl libjson-xs-perl libnet-ldap-perl libhtml-escape-perl

Compiled binaries are using some ISO-8859-1 encoding characters… to get correct display you might install some additional locale. Uncomment fr_FR ISO-8859-1 and en_US ISO-8859-1 lines in /etc/locale.gen, then:

sudo locale-gen fr_FR en_US

Also you need to activate CGI module for Apache:

sudo a2enmod cgid

Create the target WebObs directory:

sudo mkdir -p /opt/webobs

B) Upgrading WebObs <version> from its WebObs-<version>.tgz

The setup process is also used for upgrading an already installed WebObs.

setup, when ‘upgrading’ will activate new WebObs code AND only report the data/configuration differences that it can detect between your customized installation and what the new version would installed from scratch.

It is recommended to stop any WebObs-related processes before upgrading.

Configuration files will be updaded and displayed/editabled at the end of the upgrade process to help you apply required changes to configuration/data.

C) Procedure for both A) and B) above

With root privileges, in your target WebObs directory:

  1. execute cd /opt/webobs
  2. execute tar xf WebObs-<version>.tar.gz
  3. execute WebObs-<version>/SETUP/setup
  4. (re)start Apache
  5. launch the scheduler and postboard

For users of systemd-base GNU/Linux distributions, the setup proposes an automatic installation for scheduler and the postboard services. If you accepted it, you can launch both systemd services with the following commands:

sudo service woscheduler start
sudo service wopostboard start

D) Improving basemap database (recommanded)

WebObs is distributed with ETOPO5 worldwide topographic data, which is very coarse. For details maps on land, WebObs uses SRTM3 topographic data, automatically downloaded from the internet. To improve offshore parts of maps, you can freely download ETOPO1:

curl https://www.ngdc.noaa.gov/mgg/global/relief/ETOPO1/data/bedrock/grid_registered/binary/etopo1_bed_g_i2.zip -o /tmp/etopo.zip
unzip -d /etc/webobs.d/../DATA/DEM/ETOPO /tmp/etopo.zip

If the link is broken you might download a copy here (308 Mb) and untar into the WebObs root directory:

tar xf etopo1.tgz

then update the ETOPO parameters in the /etc/webobs.d/WEBOBS.rc file with the lines:


What’s new and release history

What’s new in the 2.6?

What’s new in the 2.5?

What’s new in the 2.4?

What’s new in the 2.3?

What’s new in the 2.2?

What’s new in the 2.1?

What’s new in the 2.0?

What’s new in the beta-1.8?

What’s new in the beta-1.7 ?


The WebObs system has been awarded by a “Community” accessit during the First Open Science Award Ceremony, Paris Open Science European Conference (OSEC), February 4-5, 2022. See related articles (mostly in French):


Publications on the WebObs system

  1. Beauducel, F. and C. Anténor-Habazac (2002), Quelques éléments d’une surveillance opérationnelle…, Journées des Observatoires Volcanologiques, Institut de Physique du Globe de Paris, 25 janvier 2002. PDF (in French)
  2. Beauducel, F., Anténor-Habazac, C., & Mallarino, D. (2004). WEBOVS: Integrated monitoring system interface for volcano observatories. IAVCEI General Assembly, Pucon, Chile, November 2004, poster. PDF
  3. Beauducel, F. (2006). Operational monitoring of French volcanoes: Recent advances in Guadeloupe, Géosciences, Editions BRGM, n°4, p 64-68, 2006. Abstract
  4. Beauducel, F., A. Bosson, F. Randriamora, C. Anténor-Habazac, A. Lemarchand, J-M Saurel, A. Nercessian, M-P Bouin, J-B de Chabalier, V. Clouard (2010). Recent advances in the Lesser Antilles observatories - Part 2 - WEBOBS: an integrated web-based system for monitoring and networks management, Paper presented at European Geosciences Union General Assembly, Vienna, 2-7 May 2010. Abstract
  5. Beauducel F., D. Lafon, X. Béguin, J.-M. Saurel, A. Bosson, D. Mallarino, P. Boissier, C. Brunet, A. Lemarchand, C. Anténor-Habazac, A. Nercessian, A. A. Fahmi (2020), WebObs: The volcano observatories missing link between research and real-time monitoring, Frontiers in Earth Sciences, Open Access Full Article

Publications citing or using data from WebObs


  1. Truong, F. et al. (2009). MAGIS: The information system of IPGP magnetic observatories. In Proceedings of the XIIIth IAGA Workshop on Geomagnetic Observatory Instruments, Data Acquisition and Processing, June 9-18 2008. PDF
  2. Cole P. et al. (2011), MVO scientific report for volcanic activity between 1 November 2010 and 30 April 2011, Open File Report OFR 11-01.
  3. Boissier P. et al. (2014). Acquisition, capitalization, modeling and sharing of volcanic and seismic monitoring data at La Réunion Island. In EGU General Assembly Conference Abstracts, p. 7964.
  4. Lemarchand, A. et al. (2014). Significant breakthroughs in monitoring networks of the volcanological and seismological French observatories. In EGU General Assembly Conference Abstracts p. 14987.
  5. Villemant B. et al. (2014). The hydrothermal system of La Soufrière of Guadeloupe (Lesser Antilles): 35 years of geochemical monitoring with particular emphasis on halogens tracers, J. Volcanol. Geotherm. Res., doi:10.1016/j.jvolgeores.2014.08.002
  6. Peltier A. et al. (2015). Are Piton de la Fournaise (La Réunion) and Kīlauea (Hawai‘i) Really “Analog Volcanoes”?, in Hawaiian Volcanoes: From Source to Surface (eds R. Carey, V. Cayol, M. Poland and D. Weis), John Wiley & Sons, Inc, Hoboken, NJ. doi:10.1002/9781118872079.ch23
  7. Boudoire G. et al. (2017), New perspectives on volcano monitoring in a tropical environment: continuous measurements of soil CO2 flux at Piton de la Fournaise (La Réunion Island, France), Geophys. Res. Lett., doi:10.1002/2017GL074237.
  8. Boudoire G. et al. (2017), Investigating the deepest part of a volcano plumbing system: evidence for an active magma path below the western flank of Piton de la Fournaise (La Réunion Island), J. Volcanol. Geotherm. Res., doi:10.1016/j.jvolgeores.2017.05.026
  9. Tulet P. et al. (2017), First results of the Piton de la Fournaise STRAP 2015 experiment: multidisciplinary tracking of a volcanic gas and aerosol plume. Atmospheric Chemistry and Physics, doi:10.5194/acp-17-5355-2017
  10. Boudoire G. et al. (2018). Extensive CO2 degassing in the upper mantle beneath ocean basaltic volcanoes: first insights from Piton de la Fournaise volcano (La Réunion Island) coupling CO2 He-Ar systematic and petrology of fluid inclusions. Geochimica et Cosmochimica Acta, doi:10.1016/j.gca.2018.06.004
  11. Boudoire G. et al. (2018), Small-scale spatial variability of soil CO2 flux: implication for monitoring strategy, J. Volcanol. Geotherm. Res., doi:10.1016/j.jvolgeores.2018.10.001
  12. Dumont, M. et a. (2019) Imagery of internal structure and destabilisation features of active volcano by 3D high resolution airborne electromagnetism, Sci. Rep., doi:10.1038/s41598-019-54415-4
  13. Tamburello G. et al. (2019). Spatio-temporal relationships between fumarolic activity, hydrothermal fluid circulation and geophysical signals at an arc volcano in degassing unrest: La Soufrière of Guadeloupe (French West Indies). Geosciences, doi:10.3390/geosciences9110480
  14. REVOSIMA (2019). Bulletin de L’Activité Sismo-Volcanique à Mayotte. Technical Report ISSN: 2680-1205, IPGP/BRGM. Available online at www.ipgp.fr/revosima
  15. Moretti R. et al. (2020). The 2018 unrest phase at La Soufrière of Guadeloupe (French West Indies) andesitic volcano: scrutiny of a failed but prodromal phreatic eruption, J. Volcanol. Geotherm. Res., doi:10.1016/j.jvolgeores.2020.106769
  16. Terray L. (2020). From sensor to cloud: An IoT network of radon outdoor probes to monitor active volcanoes. Sensors, doi:10.3390/s20102755
  17. Peltier, A. et al. (2021). Volcano crisis management at Piton de la Fournaise (La Réunion) during the COVID-19 lockdown, Seismol. Res. Lett., doi:10.1785/0220200212
  18. Feuillet N. et al. (2021). Birth of a large volcanic edifice through lithosphere-scale dyking offshore Mayotte (Indian Ocean), Nature Geoscience, doi:10.1038/s41561-021-00809-x
  19. Trasatti, E. et al. (2021). The Impact of Open Science for Evaluation of Volcanic Hazards. Frontiers in Earth Science, doi:10.3389/feart.2021.659772.
  20. Lowenstern, J. B., Wallace, K., Barsotti, S., Sandri, L., Stovall, W., Bernard, B., … & Garaebiti, E. (2022). Guidelines for volcano-observatory operations during crises: recommendations from the 2019 volcano observatory best practices meeting. Journal of Applied Volcanology, 11(1), 1-24. doi:10.1186/s13617-021-00112-9
  21. Chevrel, M. O., Harris, A., Peltier, A., Villeneuve, N., Coppola, D., Gouhier, M., & Drenne, S. (2022). Volcanic crisis management supported by near real-time lava flow hazard assessment at Piton de la Fournaise, La Réunion. Volcanica, 5(2), 313-334. doi:10.30909/vol.05.02.313334


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  10. Ucciani G. (2015). Caractérisation spatiale et temporelle de la sismicité volcanique de la Soufrière de Guadeloupe : relations avec le système hydrothermal, Doctorate Thesis, Université Paris Diderot, October 2015, pp. 235.
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  15. Saurel J.M. et al. (2019). High-resolution onboard manual locations of Mayotte seismicity since March 2019, using local land and seafloor stations. In AGU Fall Meeting Abstracts, Vol. 2019, pp. V43I-0220.
  16. Tan C.T. et al. (2019), Real-time assessment of potential seismic migration within a monitoring network using Red-flag SARA, J. Volcanol. Geotherm. Res., doi:10.1016/j.jvolgeores.2019.07.004
  17. Feron R. et al. (2020). First optical seismometer at the top of La Soufrière volcano, Guadeloupe. *Seismol. Soc. Am., doi:10.1785/0220200126
  18. Stabile T. A. et al. (2020). The INSIEME seismic network: a research infrastructure for studying induced seismicity in the High Agri Valley (southern Italy). Earth System Science Data, doi:10.5194/essd-12-519-2020
  19. Rizal M. H. (2020). Structure of Merapi-Merbabu complex, Central Java, Indonesia, modeled from body wave tomography. Master report, Master Solid Earth Geophysics, Université de Paris.
  20. Falcin A. et al. (2021). A machine learning approach for automatic classification of volcanic seismicity at La Soufrière volcano, Guadeloupe, J. Volcanol. Geotherm. Res., doi;10.1016/j.jvolgeores.2020.107151
  21. Massin F. et al. (2021). Automatic picking and probabilistic location for earthquake assessment in the Lesser Antilles subduction zone, CR Géoscience, doi:10.5802/crgeos.81
  22. Saurel J. M. et al. (2021). Mayotte seismic crisis: building knowledge in near real-time by combining land and ocean-bottom seismometers, first results. Geophys. J. Int., doi:10.1093/gji/ggab392
  23. Duputel Z. et al. (2021). Seismicity of La Réunion island. Comptes Rendus Géoscience, doi:10.5802/crgeos.77
  24. Falcin, A. (2022). Détection et classification des signaux sismo-volcaniques de la Soufrière de Guadeloupe par apprentissage supervisé, Doctorate Thesis, Université Paris Cité, 14 April 2022.
  25. Retailleau, L. et al. (2022). Automatic detection for a comprehensive view of Mayotte seismicity, Comptes Rendus Géoscience, doi:10.5802/crgeos.133


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  2. Beauducel, F., and Carbone, D. (2015). A strategy to explore the topography-driven distortions in the tilt field induced by a spherical pressure source: the case of Mt Etna. Geophys. J. Int., doi:10.1093/gji/ggv076
  3. Peltier A. et al. (2016), Deep fluid transfer evidenced by surface deformation during the 2014-2015 unrest at Piton de la Fournaise volcano, J. Volcanol. Geotherm. Res., doi:10.1016/j.jvolgeores.2016.04.031
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  10. Dumont, Q., Cayol, V., Froger, J. L., & Peltier, A. (2022). 22 years of satellite imagery reveal a major destabilization structure at Piton de la Fournaise. Nature Communications, 13(1), 1-11. doi:10.1038/s41467-022-30109-w
  11. Cayol, V., Peltier, A., Froger, J. L., & Beauducel, F. (2022). Monitoring Volcano Deformation. Hazards and Monitoring of Volcanic Activity 2: Seismology, Deformation and Remote Sensing, 95-165. doi:10.1002/9781394169610.ch2
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Critical Zone

  1. Gaillardet, J., I. Braud, F. Hankard, S. Anquetin, O. Bour, N. Dorfliger, et al. (2018). OZCAR: The French network of critical zone observatories. Vadose Zone Journal 17:180067. doi:10.2136/vzj2018.04.0067
  2. Guerin A., Devauchelle O., Robert V., Kitou T., Dessert C., Quiquerez A., Allemand P. and E. Lajeunesse (2019). Stream‐discharge surges generated by groundwater flow. Geophysical Research Letters. https://doi.org/10.1029/2019GL082291
  3. Fries D.M., R.H. James, C.Dessert, J. Bouchez, A. Beaumais, C. R. Pearce (2019). The response of Li and Mg isotopes to rain events in a highly-weathered catchment. Chemical Geology, 519, 68-82. https://doi.org/10.1016/j.chemgeo.2019.04.023
  4. GREC (2020). La ressource en eau et le changement climatique, Cahier du Groupe Régional d’Experts sur le Climat de la Guadeloupe. Article en ligne (in French)
  5. Guoa J., L. Maa, J. Gaillardet, P. B.Sak, Y. Pereyra and J. Engela (2020). Reconciling chemical weathering rates across scales: Application of uranium-series isotope systematics in volcanic weathering clasts from Basse-Terre Island (French Guadeloupe), EPSL 530. https://doi.org/10.1016/j.epsl.2019.115874
  6. Dessert C, Clergue C, Rousteau A, Crispi O and M.F. Benedetti (2020). Atmospheric contribution to cations cycling in highly weathered catchment, Guadeloupe (Lesser Antilles). Chemical Geology, 531. https://doi.org/10.1016/j.chemgeo.2019.119354
  7. Gaspard F., S. Opfergelt, C. Dessert, V. Robert, Y. Ameijeir and P. Delmelle (2021). Imprint of chemical weathering and hydrothermalism on the Ge/Si ratio and Si isotopic composition of rivers in a volcanic tropical island, Basse-Terre, Guadeloupe (French West Indies). Chemical Geology. https://doi.org/10.1016/j.chemgeo.2021.120283
  8. Wong, M. Y., Rathod, S. D., Marino, R., Li, L., Howarth, R. W., Alastuey, A., et al. (2021). Anthropogenic perturbations to the atmospheric molybdenum cycle. Global Biogeochemical Cycles, 35, e2020GB006787. https://doi.org/10.1029/2020GB006787
  9. Pasquet, S., Marçais, J., Hayes, J. L., Sak, P. B., Ma, L., & Gaillardet, J. (2022). Catchment-scale architecture of the deep critical zone revealed by seismic imaging. Geophysical Research Letters, 49, e2022GL098433. https://doi. org/10.1029/2022GL098433
  10. Xu‐Yang, Y., Dessert, C., Losno, R. (2022). Atmospheric deposition over the Caribbean region: Sea salt and Saharan dust are sources of essential elements on the island of Guadeloupe. JGR Atmospheres. https://doi.org/10.1029/2022JD037175
  11. Fernandez N.M., Bouchez J., Derry L.A., Chorover J., Gaillardet J., Giesbrecht I., Fries D., J. L. Druhan (2022). Resiliency of silica export signatures when low order streams are subject to storm events. Journal of Geophysical Research: Biogeosciences, 127, e2021JG006660. https://doi.org/10.1029/2021JG006660