Water knowledge has a central role in the mitigation of climate change
Aalto Distinguished Professor Olli Varis, who leads the Water and Development Research Group at the Department of Built Environment, comments on the theme of the World Water Day with a reminder: many of the impacts of climate change, such as floods, droughts and damage caused by storms are directly linked to water. The effects of temperature on precipitation, evaporation and soil water balance are all connected to the shifting of climate zones.
Varis notes that the past winter in Finland has been exceptional – and completely in line with what climate change scenarios have predicted. In addition to temperatures, this can be seen in the increased precipitation and Lapland's exceptionally large snow coverage. In the coastal areas of Southern Finland, the winter has been snowless, with forecasts showing that this will largely be the new normal.
"Climate change causes an increase in extreme climate events, which means longer and more frequent droughts and wet seasons. Research work has also been affected, as the uncertainty of long-term forecasts has grown. The local impacts of climate change are a combination of several factors, and the big picture is not fully known yet."
Transition of climate zones causes different challenges for nature and livelihoods
"Climate change touches biodiversity, desertification, agriculture, ecosystems and the well-being of people through water and temperature. One of the major impacts to ecosystems is desertification, which is already a significant risk for Mediterranean countries, such as Spain."
There is no fear of desertification in Finland, but the growing frequency of dry summers poses a risk to the environment, warns Varis. An exceptionally dry summer last occurred in 2018 and it had major impacts in Finland. Even in the land of a thousand lakes, the drought decreased the amount of usable water and in some places authorities even had to limit consumers' water usage. Of the most common tree species, spruces are especially sensitive to long periods of drought.
Varis notes that while some areas are experiencing droughts, other areas are facing more precipitation. For example, in the populous river basins of China, floods have become more extreme and frequent due to climate change.
"Therefore, hydrological expertise – local and global – is essential for understanding these phenomena and their impact. For adapting to and mitigating these effects, it is important to focus on the emissions of certain industries and agriculture, as well as the development and production of bioenergy."
Research and preparations for impacts in Finland
Varis summarises the situation by noting that unexpected changes make the forecasting of phenomena more difficult. This brings us to a question: how can droughts be forecasted in the future?
"In order to give Finland the best possible conditions for preparing for change, research is conducted in collaboration with different actors such as the Environmental Ministry, the Finnish Environmental Centre and the Natural Resources Institute. Preparing for future challenges requires not only research but a multi-layered planning process and political solutions as well."
According to Varis, the Finnish flood preparation systems are being actively developed, and Finland is participating in EU-level flood directive work. With regard to drought preparation, however, Finland has not yet been active at the EU level, though Finland has a long history of flood research.
Doctoral student Lauri Ahopelto from the Water and Development Research Group is studying droughts in Finland for his dissertation. In his research, he has estimated the vulnerability and risks of droughts in Finland for current times and for the near future. The worst drought season in modern history, 1939–42, has been modelled in his study and is being used for evaluating impacts from the perspective of climate change as well. At this moment, Ahopelto's research is looking into which indicators should be used in drought impact management.
Water and Environmental Engineering research takes on the challenges of climate change
Aalto University’s Water and Environmental Engineering group covers three research themes, which all have climate change as a central challenge. Varis’s Water and Development Research Group studies climate change from the perspective of agriculture, the energy sector, water usage and CO2 emissions. The development of low-carbon and sustainable agriculture is one of the group's central research areas.
For the Water Resources Management and Environmental Hydraulics group, climate change links especially to urban precipitation and floods as well as water resources in forests and agriculture. In the Water and Wastewater Engineering group, wastewater management and atmospheric emissions are central research themes. Municipalities and companies directly benefit from the solutions that have been developed through their work.
Varis concludes by noting that Finnish research in water and climate change is advanced and globally recognised. Its close relationship with high-level authorities and municipalities has been significant to the research and its impacts. Thus, the high quality of research has been directly linked to society’s needs and different stakeholders.
Professor Olli Varis
World Water Day is held in 22nd of March. Read more.