from Stockholm - In Stockholm, Sweden, the Nobel Prizes aren't the only awards presented. Since 1991, the Stockholm Water Prize has also been awarded, recognizing excellence in water research and protection. Although it is not affiliated with the Nobel family, this award holds significant importance. This year, the Stockholm Water Foundation and the Royal Swedish Academy of Sciences honored hydrologist Taikan Oki. King Carl XVI Gustaf of Sweden presented the award on August 28, 2024, during World Water Week.
A faculty member at the University of Tokyo, professor Oki has advanced global water management through practical climate adaptation strategies, improved integration of human activity into the water cycle, and enhanced accuracy in modelling global river flows. He was also the first to precisely measure the value of virtual water, the water required to produce the food, goods, and services we use. His research has deepened our understanding of food importation and its effects on virtual water trade and water scarcity. Renewable Matter interviewed him to explore the roots of his intuitions and his recommendations for the future .
Professor Oki, what does it mean to measure the value of virtual water?
One key message that I think we could convey is that there is no country that is both economically poor and water scarce. If you are water scarce but have economic power, you can import food from abroad. If you lack economic power but have water resources, you can produce the food you need. However, if a society is both economically poor and water-scarce it cannot exist. Water is not just the lifeblood of life; it is a crucial resource for human survival.
How do you envision the concept of virtual water evolving to address global water scarcity issues in the coming decades?
If the world were peaceful, we could allocate food production to areas with sufficient water and trade the products, allowing virtual water to compensate for water shortages. However, if the world is divided, and leaders focus only on their domestic interests, free trade may not be possible. In such a scenario, the concept of virtual water stabilizing water distribution would not work effectively. The value of virtual water depends on global peace.
What is the role of scientists in effectively communicating that idea to decision makers?
I am somewhat hesitant to prescribe specific recommendations for policymakers. What we can offer is an overview of options that might be more effective or efficient. While human beings sometimes choose less optimal options, which is difficult to prevent, I can still suggest ways that might be better or more efficient, with the goal of minimizing the overall costs.
Can we estimate when anthropogenic pressure on water resources will decrease?
The global population is expected to peak around the late 21st century, possibly in the 2080s or 2090s. This is a positive sign for humanity, suggesting that we may not need more water after that point. Resource issues should be considered until the end of this century, while by the 22nd century, we might have more freedom, stability, and sustainability. We need to focus on overcoming difficulties during this transition.
What kinds of difficulties?
We should not only consider our own regional benefits but also prioritize social stability, which is crucial. This stability depends not just on local situations but on global stability. To achieve this, we need to reduce the gap between rich and poor.
In regions with insufficient water, local water demand could be reduced by importing water-intensive goods like food or even services that require significant water, such as AI. Effective collaboration between countries is essential for managing these resources.
You’ve integrated human activity into water cycle models. How has this changed our understanding of climate adaptation strategies?
Without global modelling that includes human activities, vulnerability assessments on populations are incomplete. Without considering impacts such as increased or decreased precipitations, assessments might fail to take into account that areas with heavy rainfall may suffer greater damage, while areas with low precipitation may face increased water scarcity. By incorporating human activities, water infrastructure, and disaster mitigation measures such as levee construction or reservoirs, we can more accurately identify regions likely to experience greater damage due to climate change. The real world is no longer purely natural; it is significantly influenced by human activities, particularly in relation to the water cycle, drought, and environmental conditions.
You were instrumental in developing the Total Runoff Integrating Pathways (TRIP) system, a model that provides a more accurate depiction of the world’s river flows. Why was it important to consider the impact of these bodies of water, even in relation to human activities?
In the past, climate modelling did not take rivers into account, but the climate community now recognizes their role, although it is still seen as marginal or limited. While there isn’t much feedback on how river flow affects ocean or atmospheric circulation, rivers are a significant factor in impact assessments on human society. Water transfers the impacts of climate change to human society. Without considering river flow, it is challenging to assess the effects of climate change and its adverse impacts on human society. It was my dream to include the river component in climate modelling systems to predict future climate change. To achieve this, geographic information is used to track river flows from their sources to the ocean. While we may naively assume that rivers generally flow from higher to lower elevations, coarse spatial resolution can distort this flow pattern. Therefore, significant modifications are needed to adjust automatically generated river channels to match real river networks and that takes considerable time. I am very happy that many climate models are now using detailed TRIP geographical information on river channel networks for their simulations.
Italy is the 10th largest exporter of vulnerable groundwater through crop trade and the country is considered a climate change hot spot by the IPCC. Any advice?
Your future will likely be drier than it is now, so you should consider how to make your farming more sustainable. I recommend sustainable resource management. If you're using non-renewable groundwater, consider switching to renewable groundwater or surface water. Additionally, if your energy sources are renewable, you can produce more freshwater from recycled water or even from seawater. Secure your own sustainable, renewable freshwater sources. According to the First IPCC Assessment Report, the Mediterranean area will become much drier in the future and this has been a consistent trend over the past 30 years.
As the 2024 Stockholm Water Prize Laureate, what advice would you offer to young hydrologists looking to make a global impact?
The world is changing and younger hydrologists will witness continuous changes over the next 30 to 40 years. If you can contribute, even in a small way, to improving these changes, it will be a worthy life for you.
This article is also available in Italian / Questo articolo è disponibile anche in italiano
Cover image: Taikan Oki and H.M. King Carl XVI Gustaf of Sweden. Prize ceremony in the Stockholm city hall. Photo credit: Jonas Borg, via Flickr