A Sea That Has Never Been Constant
Prof. Edyta Roszko emphasised that sea level has never been constant. For thousands of years, its fluctuations have shaped landscapes, migrations and the development of civilisations. The researcher argues that the Earth breathes in rhythm with ice ages and warmer periods, pointing out that 20,000 years ago, sea levels were over 120 meters lower than today.
The researcher cited examples that show how natural processes transformed history: the creation of the English Channel after the Ice Age, the flooding of ancient Mesopotamia and the loss of land by the Sundaland archipelago in Southeast Asia.
Today, however, she noted, the pace of change is unprecedented. Since the late 19th century, sea level has risen by 24 centimetres, and in the next 30 years, it will rise by another 15. "What's happening now is unique not because it's never happened before – but because it's happening so quickly and right before our eyes" – she underlined.
Knowledge That Allowed Survival
The focus of the lecture was Prof. Roszko's research on the Austronesian peoples – one of the largest linguistic and cultural families in the world, inhabiting the islands of the Pacific, Southeast Asia and the Indian Ocean.
Their extraordinary seafaring skills, knowledge of the waters and adaptability made them pioneers in survival in harsh environments. Many of these communities had no access to rivers or lakes, drawing their water from underground springs or the so-called freshwater seeps at the interface between land and ocean.
One of the most fascinating discoveries the researcher discussed is the connection between the Moai statues on Easter Island and freshwater sources. "It turns out that these monumental sculptures precisely indicate the locations where freshwater could be found" – explained Prof. Roszko.
From Ancient Wells to Modern Challenges
In the second part of her presentation, the anthropologist spoke about her research in Vietnam, where for 25 years she has been documenting traditional wells built by the Cham people – one of the ancient Austronesian groups.
"These stone structures, laid without mortar, continue to function and provide fresh water, even during periods of drought" – the researcher said. This, she emphasised, proves that the resilience and knowledge of local communities can inspire contemporary survival strategies in the face of climate change.
Lessons for the Future
In the conclusion of her lecture, Prof. Edyta Roszko pointed out that the future of the Earth depended not only on technology, but also on understanding nature and our own limitations.
"Modern societies are like islands – isolated, dependent on narrow resources and specialisations. That's why we need adaptive transformation, just as ancient peoples had to adapt to changes in sea level" – she said.
According to the researcher, understanding the past allows us to design the future more consciously. Water – as a source of life, conflict and cooperation – remains one of the most important topics of the 21st century.
The lecture was a preview of the project "Global Hydroconnectivities: Beyond Oceans, Seas, and Rivers," funded by the European Research Council (ERC), which will be launched in 2026.
The event was made possible thanks to funding obtained by the University of Lodz Foundation through the OPUS Centre competition. The public project "Academic Lodz 2025 – Scientific, Creative and Multicultural" is financed from the City of Lodz budget.
Edit: Małgorzata Jasińska and Magdalena Paszko
