Glacial melt affects numerous organisms that are native to streams fed by glacial water. As the ice masses increasingly retreat, the bodies of water warm up, threatening the habitats of their cold-water inhabitants. Researchers from Eawag, WSL and an international team have now found a method of identifying future potential refugia for these cold-water organisms. This makes it possible to better protect, preserve or even develop regions further with a forward-looking approach.
Alpine regions are particularly affected by climate change – they are warming up faster than the global average. This is particularly detrimental to the endemic organisms there, which can only migrate to other regions with difficulty due to geographical barriers. This poses great challenges especially for water organisms. Accustomed to cold water, their only option is to flee “upstream”. And if a glacier disappears completely, they will disappear too.
To ensure the survival of these species, it is important not only to locate future new habitats, but also to protect them accordingly. Christopher Robinson of Eawag’s Aquatic Ecology department and colleagues from WSL and from the UK, Austria, France and Italy have now developed a method for modelling these future areas so that appropriate protective measures can be taken at an early stage. Their results have just been published in the renowned journal “Nature Ecology & Evolution”.
Projections up to the year 2100
To do this, the researchers used the projections of the global glacier evolution model, which predicts the spread and retreat of existing glaciers in the coming years. From this, it is possible to deduce how the bodies of water in the regions currently still covered in ice will change when the glacier melts. In combination with temperature forecasts, the team was also able to model how the existing bodies of water and indigenous habitats will develop for a total of 15 species of invertebrates and where these will find the conditions to which they are accustomed in future. The study covers the European Alpine region and the period up to the year 2100. The modelling techniques developed by the researchers can now also be used in other mountain ranges to derive forecasts there as well.
A glacial stream meanders through the fields of Odenwinkelkees, Hohe Tauern, Austria. The further the glacier retreats, the warmer the water in the lower part of the river becomes.
(Photo: Lee Brown)