Change in observed long-term greening across Switzerland – evidence from a three decades NDVI time-series and its relationship with climate and land cover factors

Article Article scientifique Article Change in observed long-term greening across Switzerland – evidence from a three decades NDVI time-series and its relationship with climate and land cover factors eng 2023-10-20 2023-10-20 author Obuchowicz Claire Barbara Lisa Institute for Environmental Sciences, EnviroSPACE lab, University of Geneva, Geneva, Switzerland 855444 author Poussin Charlotte 0000-0002-3086-1341 Institute for Environmental Sciences, EnviroSPACE lab, University of Geneva, Geneva, Switzerland 676396 Services communs de l'Institut des sciences de l'environnement (ISECO) author Giuliani Gregory 0000-0002-1825-8865 Institute for Environmental Sciences, EnviroSPACE lab, University of Geneva, Geneva, Switzerland 94488 Services communs de l'Institut des sciences de l'environnement (ISECO) 1-32 10.1080/20964471.2023.2268322 2574-5417 https://www.tandfonline.com/doi/full/10.1080/20964471.2023.2268322 Environmental changes are significantly modifying terrestrial vegetation dynamics, with serious consequences on Earth system functioning and provision of ecosystem services. Land conditions are an essential element underpinning global sustainability frameworks, such as the Sustainable Development Goals (SDGs), requiring effective solutions to assess the impacts of changing land conditions induced by various driving forces. At the global scale, long-term increase of vegetation greening has been widely reported notably in seasonally snow-covered ecosystems as a response to warming climate. However, greening trends at the national scale have received less attention, although countries like Switzerland are prone to important changing climate conditions. Hereby, we used a 35-year satellite-derived annual and seasonal time-series of Normalized Difference Vegetation Index (NDVI) to assess vegetation greenness evolution at different spatial and temporal scales across Switzerland and related them to temperature, precipitation, and land cover to investigate possible responses of changing climatic conditions. Results indicate that there is a statistically significant greening trend at the national scale with an NDVI mean increasing slope of 0.6%/year for the 61% significant pixels across Switzerland. In particular, the seasonal mean NDVI shows an important break for winter, autumn and spring seasons starting from 2010, potentially indicating a critical point of changing land conditions. At biogeographical scale, we observed an apparent clustering (Jura-Plateau; Northern-Southern Alps; Eastern-Western Alps) related to landscape characteristics, while forested land cover classes are more responsive to NDVI changes. Finally, the NDVI values are mostly a function of temperature at elevations below the tree line rather than precipitation. The findings suggest that multi-annual and seasonal NDVI can be a valuable indicator to monitor vegetation conditions at different scales and can provide complementary observations for national statistics on the ecological state of vegetation to monitor land affected by changing environmental conditions. This work is aiming at strengthening the insights into the driving factors of vegetation change and supporting monitoring changing land conditions to provide guidance for effective and efficient environmental management and sustainable development policy advice at the national scale. Landsat Climate Land cover NDVI Anomaly Dewey 500 Dewey 333.7-333.9 18 Institut des sciences de l'environnement 0DB 2 Faculté des sciences 1 false 673 Envirospace Lab 1057 TIGERS 859 Global Resource Information Database (GRID) 941 ISE Pôle Informatique environnementale 938 ISE Pôle Sciences 970b71ee-b344-4440-bc52-c9af263975d0 Living Earth Lab Big earth data 46e09f90-eca0-47b8-803a-851458c79647 Article (Published version) Public Change in observed long-term greeni1.pdf 9277783 application/pdf CC BY-4.0 ac4f285f5a2cc133d0caad0d880d5a2f1f3a28b258e9d0da12c6b43c5c98b607 openAccess Centres et instituts / Institut des sciences de l'environnement Faculté des sciences

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Change in observed long-term greening across Switzerland – evidence from a three decades NDVI time-series and its relationship with climate and land cover factors	Big earth data			2023	128	124

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Obuchowicz, Claire Barbara Lisa