GePaSud — Geopole of the South Pacific • Recherche UPF

Description

The Laboratory for Resilience in Island Territories

Founded in 2000, the South Pacific Geopole (GEPASUD) is an internal laboratory at the University of French Polynesia, focused on the resilience of island territories..

Scientific composition of the GEPASUD — **A summary diagram of the specialties and areas of action of the GePaSud teams.**

To read further :

Structuration of the Unit (teams)
Context and Societal Challenges
The GEPASUD: A Dynamic and Committed Team
History of the Unit
Citations and Impact Factors
Software and Patents

The GEPASUD laboratory is renowned (according to Google Scholar) for having accumulated at least 8,593 citations of its members’ articles between 2014 and 2024. :

Membres du GePaSud	Depuis 1996	Depuis 2019
Citations	12233	5189
h-index	58	36
i10-index	239	134

GePaSud has at least 239 articles that have been cited at least ten times and at least 58 articles that have been cited at least 58 times. Source: Google Scholar, Google Scholar Profile, https://scholar.google.com/citations?user=RNyPw5UAAAAJ&hl=en

**Tide gauge (on the left) and the Vairao tide gauge (Tahiti), in collaboration with UPF and Team No. 1 of the GePaSud laboratory.**

Structure of the unit (teams) and scientific themes.

The laboratory consists of ten teacher-researchers, an Emeritus Professor, and several doctoral and post-doctoral researchers (depending on the period), organized into three teams and main scientific themes.:

The GeoSciences Team – The scientific theme pursued by the first team is related to physical sciences and natural hazard prevention. Their work includes numerical weather prediction models (spatial and temporal distribution of water vapor), interpretation of terrestrial and oceanic tide gauge data, soil balance and granular media, micro-circulation in lagoons, hydrology, monitoring and control of water resources, watersheds, and island flow models.

In the field of geomatics, the team also focuses on remote sensing techniques and image processing applied to the Polynesian context, utilizing high-definition radar and multispectral imaging for the identification of vegetation cover and land use. They rely on standardized OGC/ISO (Open Geospatial Consortium) Web-GIS systems to make spatial data, including remote sensing data and data from the Geodetic Observatory, available to the scientific community..

On the left: Dr. Lydie Sichoix (Team 1) in the field with her students. On the right: Maximum floods over the past ten years in m³/s..

On the left: Dr. Stoll (Team 1) supervises a master’s student on the Tetiaroa atoll to launch a GPS measurement campaign. On the right: Hypnotic Lidar image of a coconut tree on the Tetiaroa atoll, reconstructed by Team No. 1. Watch the video. https://www.youtube.com/watch?v=VwN5uhs9oxs !

The Energy Team – The second team focuses the majority of its work on the energy transition in Polynesia. Their activities are organized around several approaches: structural energy improvements in buildings, development of modular and portable energy storage solutions, and the creation and enhancement of alternative energy solutions (SWAC, renewable energies). Given the novelty of this theme, the research programs are supported by numerous but strong national collaborations (FEMTO-ST, PROMES, LMD-Polytechnique, among others).

Professor Lucas (Team No. 2), interviewed regarding his work on the SWAC system of the Tetiaroa atoll (2021).

The Computer Science Team – The focus of the third team covers signal and image processing, artificial intelligence, computer science, and networks. They provide Research and Development support to local stakeholders and aim to assist the other teams in feeding data into the models they develop.

Professor Gabillon (Team No. 3, on the right) and his doctoral student, Mr. Loesdau, discuss with local stakeholders to leverage UPF research through technology transfer. (2018, http://www.assemblee.pf/actualite/article/un-projet-de-convention-de-collaboration-entre-l_universite-de-la-polynesie-fran/7404)

Many modern issues, whether industrial, ecological, or political (such as territorial sovereignty), require the collection of large-scale information, its aggregation, and processing. Team No. 3 leverages measurement instruments, innovative networks (Internet of Things), and machine learning techniques (SVM, Deep Learning, etc.) to provide theoretical advancements to the scientific community and technical solutions to civil society. The team is also focused on the protection and security of this data.

Context and Societal Challenges

With 5 archipelagos and 118 islands, French Polynesia represents a vast territory dotted with small, idyllic paradises. While these destinations are havens of peace far from the bustle of the mainland, blessed with fish-rich waters and endemic plant and animal species, living there can sometimes be quite challenging. The unique characteristics of Polynesian territories highlight the difficulties faced by their inhabitants: the dispersion of islands and atolls can quickly turn tranquility into isolation, and their supply chains are heavily dependent on the state of the sea and weather conditions, as well as on a strong reliance on imported fossil fuels for energy.

**French Polynesia is highly vulnerable due to its dependence on fossil fuels.**

Weather phenomena can be so intense in this region that French Polynesia holds the world record for rainfall, with populations regularly exposed to devastating floods and marine inundations.

**Illustration of the recurrence of major weather events in French Polynesia (Tahiti) as depicted in the press.(2015[2];2015[3];2016[4];2017[5]; 2017[6];2017[7];2022[8]).**

One of the main sources of income for French Polynesia is tourism, drawn by the stunning landscapes, lush vegetation, and the richness of its lagoons and ocean. However, the influx of visitors to its archipelagos also contributes to the introduction of invasive animal and plant species, posing a threat to the region’s endemic species. Moreover, the vastness of the marine territory makes it difficult to monitor and protect against illegal exploitation. Global energy and health crises further complicate this situation by disrupting tourism, energy supplies, and transportation.

On the left: The ARAGO patrol vessel of the French Navy departs from Tahiti to inspect a suspicious ship reported between the Tuamotu and Marquesas archipelagos. **[9]**; On the right: Feral cats—having returned to a wild state—pose a threat to Polynesian biodiversity. **[10]**.

Thus, the challenges faced by French Polynesia are numerous: unequal access to fresh water, unpredictable weather, unreliable renewable energy sources, pollution, high temperatures, climate change, floods and related damage, energy and food dependence, among others. Addressing these issues, whether individually or collectively, requires significant resources that are often beyond the reach of a country with modest income and limited exploitable land area. Consequently, Polynesian ways of life remain highly vulnerable.

Défis — **Key Scientific and Technical Challenges Faced by French Polynesia:** **The country remains highly vulnerable to global crises—whether political, ecological, or meteorological.**

To enable French Polynesia to be less dependent on the outside world and more resilient to global crises, it must become more self-sufficient in terms of resources: meeting technological development needs locally, reducing energy dependence by leveraging its own resources, and gaining a better understanding and control of natural and human-made phenomena. In short: more resilient.

But each challenge also defines the corresponding problem to be solved, and French Polynesia must therefore improve its water management, anticipate weather conditions and the availability of renewable energy, find ecological solutions to food preservation issues, and ensure that even the most remote areas are supplied with energy to guarantee their monitoring and sustainability.

Scientific complex to solve resilience issues of FP — **The challenges faced by French Polynesia define the scientific problems that need to be addressed.**

However, while the challenges are numerous, it is crucial to recognize that they are all interconnected. For instance, to better manage freshwater resources and predict floods, there is a need to improve small-scale and short-term weather predictions. This, in turn, requires the ability to anticipate the availability of solar, wind, and hydroelectric energy. Consequently, energy production systems and networks must be adapted accordingly. Furthermore, improving weather forecasts involves gaining a better understanding of the sea, atmosphere, land, and their vegetation cover. Therefore, these Polynesian issues cannot be addressed in isolation; they represent a complex network of interconnected scientific challenges.

To overcome this complex network of challenges, it is essential to approach it as a whole rather than as a collection of isolated problems. Global models need to be developed that benefit from improvements in all the involved domains: large- and small-scale models of vegetation, marine environments, weather, hydrology, and geography. These models should be leveraged to create sustainable long-term ecological alternatives for energy and refrigeration. To make these models viable, a sufficient amount of data is needed, collected from a variety of sensors. However, existing solutions are prohibitively expensive, and their telephonic or satellite operations are beyond reach.

New networks and sensors, based on emerging low-cost, low-power, low-import-cost, and low-carbon-impact technologies—referred to as “low-4″—must be designed to enable continuous, low-cost, and environmentally friendly monitoring.

A new paradigm of scientific synergies must be employed, and GEPASUD is one of the solutions to addressing this complex network of challenges.

Societal challenge and the GEPASUD — **Cross-Cutting Actions of GEPASUD**

Organized into three thematic teams, the GEPASUD laboratory brings together and converges the necessary expertise for research and development aimed at providing coordinated, viable, and economically advantageous solutions to help French Polynesia manage its territory. The laboratory defines its actions around three major societal challenges: territorial management (environmental monitoring), protection against natural hazards, and support for the economy and the professional sector through contributions in research and development.

GEPASUD is a cross-disciplinary research laboratory dedicated to enhancing the resilience of French Polynesia. To address a complex web of intertwined issues, it is structured around three major specialties and scientific domains, conducting cross-cutting research within the Polynesian context to help the region better manage its territory. A key strength shared by all teams within the laboratory is their ability to integrate scientific research with local challenges.

GEPASUD is primarily a cross-disciplinary research laboratory, with its projects situated at the intersection of three major scientific fields: physics, mathematics, and computer science. Its objectives are to better understand natural processes, model, simulate, and predict the phenomena involved, and use the best tools to propose scientific and technical applications and improvements. The laboratory’s organization around cross-disciplinary research is its response to the complex set of challenges faced by French Polynesia.

Simulation of the temperature evolution over decades — Hourly surface temperature prediction tests conducted in 2013 for long-term climate warming forecasts in French Polynesia.

comment la résolution spatial d'un modèle de climat influence la représentation de la topographie. — How the spatial resolution of a climate model influences the representation of topography.

Since its inception, GEPASUD has achieved numerous advancements and accomplishments, including disseminating knowledge, collecting extensive data, studying various environmental models, developing new methods, and carrying out technology transfers accompanied by patent filings.

Soil analysis and modeling, atmosphere and humidity studies, island flow simulations, flood forecasting and warning systems, new methods for energy production, storage, and management, innovative building models, satellite and Lidar imaging, sensor networks, new data aggregation techniques, and artificial intelligence are just some of the efforts undertaken by the GEPASUD laboratory staff. These initiatives aim to leverage their respective expertise to enhance the resilience of French Polynesia in the face of its challenges, while also contributing to the advancement of science and knowledge.

GEPASUD: A Dynamic and Committed Team

With only 4.5 permanent researchers (9 teacher-researchers at 50% research time), GEPASUD has accumulated hundreds of publications and over 12,000 citations. As of January 2024, it had 58 articles cited more than 58 times and over 239 articles cited more than 10 times.

**GEPASUD Laboratory Staff in 2024 and Impact of Its Scientific Production**

The research teams at the GePaSud laboratory have organized themselves to make the most of the available strengths and resources. The projects they undertake contribute to the development of realistic solutions—sometimes patented—to enhance our technical, energy, and environmental management. This is achieved through the development of new theoretical and practical methods for measurement, analysis, and prediction.

**Left:** October 2015, an employee of the Marine Resources Directorate inspects pearls one by one to ensure their quality before export.
**Right:** Dr. Loesdau, a former doctoral student of GEPASUD, checks the installation of new image processing software that will facilitate the operator’s work.

The laboratory collaborates with numerous institutes and organizations at both local and international levels:

https://www.google.com/maps/d/embed?mid=1dnbOIcu1ZHfApPyrJkGiF1UtpxqhK1c&ehbc=2E312F

**International collaborations of the GEPASUD** (2024)

But its members are also actively involved in knowledge dissemination and in the administration of the University.

Professor Ortega (Team 2) served as Vice-President of the Scientific Council of UPF, while Professors Gabillon (Team 3) and Lucas (Team 2) successively held the position of Director of the Pacific Doctoral School (top). In the bottom photo, the UPF Leadership Team: Professor Capolsini (Team No. 3, third from the left) is the President of the University, and Dr. Chabrier (Team No. 3, second from the right) was the Deputy Director of GEPASUD and is Vice-President of Digital Affairs at UPF.

**Paul Mauger, a PhD student at GEPASUD in the Energy team, presents the latest IPCC report on climate change at one of the “Savoir Pour Tous” conferences at UPF (2024).**

The teams at GEPASUD also host numerous master’s and doctoral students.

**Dr. Hopuare, Deputy Director of GEPASUD, presents the challenge of predicting small-scale winds to her students (2017).** Source: https://la1ere.francetvinfo.fr/polynesie/tahiti/punaauia/marania-hopuare-enseignante-chercheuse-470253.html

To ensure scientific cooperation and regular monitoring of its students, the laboratory holds weekly meetings, allowing everyone to discuss the topics that matter most to them.

**Kanhan Sanjivy, a PhD student at GEPASUD in the Energy team, presents the SWAC system during a laboratory seminar to representatives from the DPE and ADEME (2024).**

To broaden everyone’s knowledge and create a common scientific culture essential for the cross-disciplinary nature of research, the unit regularly invites its students, as well as members of other organizations, to present their activities.

History of the Unit

The unit, titled GePaSud (South Pacific Geopole, EA 4238) since 2012, is the successor of the Terre-Océan laboratory, which was established in 2000 as a “Young Team” at the University of French Polynesia on the Outumaoro campus in Tahiti.

Originally, this laboratory brought together teacher-researchers in geosciences, geomatics, and biology, focusing on topics related to French Polynesia and the Pacific Basin. From its inception, it was connected to the Tahiti Geodetic Observatory (OGT), a tripartite structure involving CNES, NASA, and UPF, dedicated in particular to the precise tracking of satellites.

The biology component separated in 2004 to form an autonomous laboratory along with another organic chemistry component, which was later integrated into the UMR EIO.

**The OGT (on the left) and the former site of the GePaSud laboratory (on the right, before 2023).**

The laboratory and the OGT were originally located at the highest and most isolated point of the UPF campus to ensure the security of equipment and the quality of measurements. It is worth noting that the upcoming move to the new Research Building will relocate the GePaSud laboratory to new facilities.

Left: Professor Barriot (Emeritus Professor, GeoSciences Team) served as Director of the GePaSud laboratory and the Tahiti Geodetic Observatory (OGT) for 17 years. The OGT is a laser geolocation unit for satellites, in collaboration between NASA and UPF.
Right: Mantle-core model of the Martian moon Phobos (27 x 22 x 18 km).

Citations et Impacts

Citations of the work of GePaSud members according to Google Scholar (September 2022). The citation rate of the laboratory’s work has been steadily increasing, surpassing a thousand citations per year in 2021.
https://scholar.google.com/citations?user=RNyPw5UAAAAJ&hl=en

Impact Factors (IF) and indexes of a large sample of journals where GePaSud published between 2016 and 2021 (average IF: 3.98, average H-index: 172.2). GePaSud publishes in highly visible and well-ranked journals.(https://www.resurchify.com/impact/ranking).

**Samples from the period 2016-2021. GePaSud publishes in journals with high Impact Factors and high H-indexes.**

Awards and Student Laureates

2023: Tobias Fischer (left), a PhD student at GEPASUD, won the Best Poster Award at the 2023 UPF Doctoriales, with a prize of 100,000 XPF generously offered by the company TEP, to whom we extend our sincere thanks.

2021: The jury members of the 3rd edition of “My Thesis in 180 Seconds” and the large audience present on Wednesday unanimously chose Garance Tanguy (left), a second-year PhD student in hydrology, for her presentation on her thesis topic “Flood Modeling in Tahiti with Applications for Infrastructure Design and Real-Time Forecasting.” She won both the 1st Prize from the jury and the Audience Award. https://www.tntv.pf/tntvnews/polynesie/societe/ma-these-en-180-secondes-garance-tanguy-et-yasmina-taerea-vont-en-demi-finale-nationale/

2018: Franco Ferrucci (left) was awarded the prize in the category “Best Economic or Cultural Valorization Prospect” for his study on thermochemical storage technology applied to building air conditioning. He received a check for 100,000 F from the president of the Tahiti Fa’ahotu competitiveness cluster, Jean-Paul Peillex. https://actu.fr/polynesie-francaise/papeete_98735/10e-edition-des-doctoriales-vahine-rurua-grande-laureate_27972957.html

**2017:** The prize for the thesis offering the best prospect for economic or cultural valorization, worth 100,000 FCP, was awarded by Mr. Jean-Paul Peillex, President of the Tahiti Fa’ahotu Innovation Cluster, to Gaël Mondonneix (GEPASUD, right) for his presentation “Automatic Recognition of the Quality of Tahitian Pearls.”
https://www.upf.pf/fr/actualites/et-les-laureats-de-ledition-2017-des-doctoriales-de-polynesie-francaise-sont

Software and Patents

Patent: Strouthidis, Nicholas; Girard, Michael Julien Alexandre; Mari, Jean Martial; Mehta, Jodhbir; Nicolas, Foin; Signal compensation optical coherence tomography system and method, 2018,”US Patent App. 15/570,694″;

Patent: PCT/SG2016/050202, Strouthidis N, Girard MJA, Mari JM, Mehta J, Nicolas F. Signal compensation optical coherence tomography system and method. Published online July 20, 2017. https://patentscope.wipo.int/search/en/detail.jsf?docId=WO2016175707

PCT Extension of patent FR1670752 : Procédé de détermination de l’épaisseur de nacre sur une perle, notamment une perle de culture. Déposant ; Université de la Polynésie Française. Inventeurs : M. Loesdau, S. Chabrier, et A. Gabillon. Numéro dépôt PCT : PCT/EP2017/082416

Patent: Procédé de détermination de l’épaisseur de nacre sur une perle, notamment une perle de culture. Déposant ; Université de la Polynésie Française. Inventeurs : M. Loesdau, S. Chabrier, et A. Gabillon. Date de dépôt : 12/12/2016. Numéro de dépôt: FR1670752.

Software: Martin Loesdau, Sébastien Chabrier, Alban Gabillon. Logiciel MAIAO basé sur brevet FR1670752 implanté sur les machines à rayon X de la Direction des Ressources Minières de Tahiti. Voir https://actu.fr/economie/perliculture-un-nouvel-outil-pour-la-qualite-des-nacres_35849080.html

Software: Firas Al Khalil, Alban Gabillon and Patrick Capolsini. Plugin PRODIGE livré au Service Informatique de la Polynésie Française en charge de la base de données cadastrale. 2016. Voir : https://www.tahiti-infos.com/Le-cadastre-du-fenua-accessible-depuis-son-domicile_a154566.html

[1] https://la1ere.francetvinfo.fr/polynesie/intemperies-3-milliards-fcp-degats-445519.html

[2] https://www.cnews.fr/france/2022-01-14/polynesie-francaise-larchipel-de-la-societe-en-vigilance-rouge-pour-fortes-pluies

[3] https://la1ere.francetvinfo.fr/polynesie/tahiti/inondations-la-cote-est-sous-les-eaux-314573.html

[4] https://www.tntv.pf/tntvnews/polynesie/societe/intemperies-2-habitations-isolees-a-tipaerui-appel-a-la-vigilance-a-faaa/

[5] https://www.lexpress.fr/actualites/1/societe/tahiti-au-ralenti-cinq-jours-apres-des-inondations-devastatrices_1873604.html

[6] https://www.tahiti-infos.com/inondations-a-Taapuna-la-route-rouverte-a-la-circulation_a156958.html

[7] https://www.tahiti-infos.com/Intemperies-a-Tahiti-la-piste-aeroportuaire-est-fermee-jusqu-a-nouvel-ordre_a157036.html

[8] https://la1ere.francetvinfo.fr/polynesie/tahiti/fortes-pluies-sur-la-societe-les-rivieres-debordent-1202971.html

[9] https://de-de.facebook.com/photo/?fbid=1438162233053740&set=a.484177578452215

[10] https://www.tahiti-infos.com/Les-chats-sauvages-menacent-la-faune-polynesienne_a194784.html

[11] https://www.radio1.pf/le-pays-discute-dune-nouvelle-reglementation-avec-les-perliculteurs/