Research programme Forests and Climate Change

The goal of the research program “Forests and Climate Change” was to find out how Swiss forests will react to climate change. We thereby studied impacts on forest goods and services and develop adaptation strategies to preserve those. The program ran between 2009 and September 2018.

Climate change and its impacts on humans and the environment are among the central societal challenges of the 21th century. According to the current scenarios of the International Panel on Climate Change the climate over the next 100 years in Switzerland will become warmer, dryer and more extreme.

The program “Forests and Climate Change” was launched in 2009 as a joint effort of the Federal Office for the Environment (FOEN) and WSL. It has come to an end in September 2018. Within its scope solid fundamentals were developed to evaluate the effects of climate change on tree species composition and forest growth. The outcome of the program has been presented in a scientific synthesis (“Wald im Klimawandel” available in German and French see below), which has reached the following conclusion: How a forest is affected by climate change strongly depends on stand properties and site conditions, and the ability of forest sites to absorb climate change is limited. The positive message is that adapting forest management will contribute to maintaining forest goods and services, especially if the tree species composition is adjusted to the new climate,. This can be achieved if forest managers systematically and continuously evaluate management effects and adjust the management where needed.   

To be effective the programs’ outcomes are made available to stakeholders like employees of forest services, forest managers, forest owners and policy makers. This implementation effort is essential to help forest stakeholders to evaluate risks and chances due to climate change and take the right measures to meet those. Important implementation products were the scientific synthesis “Wald im Klimawandel” (see below), two outreach conferences (“Forum für Wissen”, November 2016, and “Forum Suisse Romande”, Mai 2017), the WSL leaflet series “Merkblatt für die Praxis” as well as a series of articles in the professional journals “Wald und Holz” and “La Forêt” (all available in German and French), as well as many fruitful discussions with forest stakeholders in the forest within the frame of the “Waldtests” project. At the moment we are developing tools which will help to evaluate how forest site conditions develop, in order to enable managers choose the right tree species.

The outcomes of this program are an important foundation for the federal strategy for forest and forest management, as components of the national climate change adaptation strategy. Moreover, the outcomes  support the political implementation of the federal “Forest policy 2020”.


Important results of the science program were published as book in November 2016 (book available in German and French only) 

All research projects

Project manager
(leading institution)

N. Zimmermann (WSL)

PorTree – Environmental portfolio of Central European tree species (completed project: final report EN)

M. Rebetez (WSL)

Below canopy climate and climate trends (completed project: final report EN)

D. Kurz (EKG Geo-Science)

Validation and improvement of the integrated dynamic forest ecosystem model ForSAFE at Swiss ICP forests level II sites (LWF - Longterm Forest Ecosystem Research Program)

P. Waldner (WSL)

NitLeach - Nitrate leaching under changing climatic conditions and forest management

E. Thürig (WSL)

KLIWAWA - Improving the climatic dependency of growth functions for various scenario analyses of forest dynamics (wood utilisation potential, sustainability) (completed project: final report DE)

P. Lüscher (WSL)

Effects of climate-related changes in tree species composition on root penetration and hydrological processes in forest soils (completed project: final report DE)

K. Bollmann (WSL)

Predicted effects of climate change on indicator species of structural and biological diversity in mountain forests: towards adaptive forest management in the face of environmental unvertainty (completed project: final report EN)

M. Küchler (WSL)

Climatic effects on forest vegetation (completed project: final report DE)

B. Wermelinger (WSL)

BarBeeKey - Bark beetles as key factors in the future utilisation of forest resources? (final report DE)

M. Conedera (WSL)

ALPFFIRS - Alpine Forest FIre waRning System (completed project: final report EN)

M. Conedera (WSL)

WUI-CH - Wildland-Urban Interface (WUI) and forest fire ignition in Alpine conditions (completed project: final report EN)

B. Pauli (HAFL)

The economic consequences of spatially and temporally differentiated adaptation strategies in the forest (completed project: final report DE)

H. Bugmann (ETH Zürich)

Adaptive management strategies to maintain ecosystem services of Swiss mountain forests: Using mechanistic models to test forest management options under climate change (completed project)

P. Bebi (WSL)

Development and services of protection forest under the influence of climate change (completed project: final report DE)

N. Holthausen (Ernst Basler+Partner)

Future prospects and risk management for forestry enterprises: Dealing with risks of climate change (completed project: final report DE)

T. Wohlgemuth (WSL)

TroLiFa-Regeneration - Drought as a limiting factor for establishment and growth of the main tree species (project continued TroLiFa-Plus: final report DE)

B. Moser (WSL)

TroLiFa-Plus - Drought as a limiting factor for establishment and growth of the main tree species - link to other projects and regional relevance. (completed project: final report DE)

C. Körner (Universität Basel)

MATCHTREE – Drought sensitivity of trees; Low temperature-related tree limits (completed project)

C. Heiri (WSL)

ADAPT - Adaptive genetic variation in beech, spruce and fir (completed project: final report DE)

P. Brang (WSL)

Exotic tree species (project extended until end 2015, follow up WSL project, completed project: final report DE)

J. Remund (Meteotest)

Site-specific risk assessment of drought stress in Swiss forests (completed project: final report)

R. Siegwolf (PSI)

Drought vulnerability of conifers in Switzerland: a multiproxy approach (completed project: final report)

H. Bugmann (ETH Zürich)

Retrospective and prospective analysis of the sensitivity of Swiss forest types to changes in climate

S. Braun (IAP)

The impact of climate change on the water relations of various forest tree species

P. Weber (WSL)

Climate vulnerability of forests in the Plateau region (completed project: final report)

A. Rigling (WSL)

Relative mortality rate as an indicator of forest sensitivity (completed project: final report)

J. Remund (Meteotest)

Climatic data for forest modeling in the 21. century (completed project: final report)

S. Braun (IAP)

The suitability of various drought indices for assessing drought risks for forests and their site-specific development from 2050 through 2100 (completed project: final report)

N. Zürcher-Gasser (Gadola AG)

Regeneration of the main mountain tree species under climate change: pilot project for silvicultural decision-making (completed project: final report DE)

L. Walthert (WSL)

BOWA-CH - Soil properties and water balance of Swiss forests and forest habitats under the present and future climate (completed project: final report DE)

B. Huber (Abenis AG)

A climate-based explanation of boundaries between ecogram sites selected by NaiS (completed project: final report DE)

F. Gugerli (WSL)

QuercAdapt - The relationship between ecological gradients and adaptive genetic variation in oak (completed project: final report EN)

R. Schwitter (Mountain Forest Preservation Services)

The possibilities and limits of practice-oriented monitoring networks (completed Project: final report DE)

A. Buttler (WSL)

CLIMARBRE - Ecological response of beech and Norway spruce to climate change along an altitutdinal gradient (completed project: final report EN)

B. Pezzatti (WSL)

Forest fire danger potential and climate change (completed project: final report EN)

E. Thürig / M. Hanewinkel (WSL)

Parameterizing a climate sensitive forest dynamic model for Switzerland (completed project: final report EN)

J.-J. Thormann (HAFL)

Treasure of experience from the practice (completed project: final report DE)

N. Zimmermann (WSL)

TempEx - Developing spatial layers of climate temperature extremes (completed project: final report EN)

P. Waldner (WSL)

NitLeach II - Nitrate leaching risks mapping

N. Zimmermann (WSL)

ForReg - Forest regeneration in Switzerland (completed project: final report EN)

A. R. Pluess (WSL)

Scientific synthesis of the program (completed project; see book "Wald im Klimawandel"; DE, FR)

M. Frehner (Monika Frehner Ingenieurbüro)

Adapted ecograms (completed project: final report DE)

T. Wohlgemuth (WSL)

Dice-risk - Potential invasiveness of Douglas fir in Central Europe (completed project: final report DE)

G. Kaufmann (Kaufmann+Bader GmbH)



Associated projects

P. Weber (WSL)

Competitivity and site sensitivity of tree species (completed project)

U. Mühlethaler (HAFL)

Regenerative capacity of Mediterranean beeches in Swiss forests (beech tree seedlings project; completed project)