Is the record-breaking heat in the Alps depleting water reserves?

How hot is it in the Alpine regions?

Giacomo Bertoldi: Over the past few nights, several locations in the Adige Valley have recorded tropical temperatures – that is, above 20 degrees. On the night of May 27–28, the temperature in Bolzano even reached 21.3 degrees.

In Brunico/Bruneck, at an altitude of over 800 meters, temperatures exceeded 30 degrees during the day, and the freezing level was recorded only above 4,000 meters.

The change was sudden; until mid-May, it was very cold. On Sunday, May 18, it even snowed, and in Marmolada/Marmolata, many people were skiing on powdery snow like that found in January.

How can these events be explained from a scientific perspective?

Alice Crespi: The climate is changing, and this is making such events increasingly frequent.

In a study, we analyzed the heat waves and drought events that affected the Adige River basin from 1950 to 2023. These conditions, combined with early snowmelt and prolonged dry spells, can exacerbate the decline in river flow and increase water stress.

We must also consider another factor: the time of year when a heatwave occurs has a huge impact on the severity of its effects. In late spring, when water reserves still need to sustain the summer, the consequences can be particularly severe.

What lesson can we draw from this?

Bertoldi: The climate, shaped in large part by human activity, can no longer manage its reserves sparingly. Snow still accumulates during periods of cold, yet the increasingly intense and prolonged heat waves that follow, rapidly exhaust water resources, while glaciers quickly lose the protective blanket which has built up over winter.

Our actions have transformed the climate. It is no longer the careful saver our grandparents once knew, preserving resources for harder times. Instead, it has become like the grasshopper in the fable, consuming everything frivolously, with little thought for future provisions.

What can we do to avoid this situation?

Bertoldi: We must stem this situation: if the climate is such a spendthrift, we as a society must “save” more, manage our water resources more prudently, and not let ourselves be caught unprepared.

How can research help?

Crespi: Research can help transform the vast amount of data we have into concrete strategies to mitigate risks and promote more sustainable water resource management. Eurac Research’s research activities on the topic of drought are wide-ranging and include the development of monitoring tools, such as the Alpine Drought Observatory ADO, forecasting systems, such as in the A-DROP project, and future projections of water availability and its uses in South Tyrol, such as in the NextWater_ST project.