Towards rainy high Arctic winters: how experimental icing and summer warming affect tundra plant phenology, productivity and reproduction

The Arctic is warming rapidly, and much faster in winter than in summer. Warm spells in winter lead to more frequent extreme rain-on-snow events that alter snowpack conditions and can encapsulate plants in ‘basal ice’ (‘icing’) for months. Yet, how icing affects plant communities, especially over multiple winters and under warmer summers, remains largely unstudied.
We investigated winter icing and summer warming effects on vascular plants’ productivity, reproduction and phenology in mesic dwarf-shrub heath, an important reindeer habitat in high Arctic Svalbard, where winter temperatures have been rising particularly fast. In a full factorial field experiment, rain-on-snow and resultant icing were simulated in five consecutive winters, and each followed by experimentally increased summer temperatures. Vascular plant responses at the community-level, with particular attention to the dominant dwarf shrub Salix polaris, were assessed throughout each subsequent growing season.
Icing alone in..., Please refer to the methods of the open access publication: 
Le Moullec et al. (2025) Towards rainy high Arctic winters: how experimental icing and summer warming affect tundra plant phenology, productivity and reproduction.
Published in Journal of Ecology, Accepted on 31 October 2025.
, # Towards rainy high Arctic winters: how experimental icing and summer warming affect tundra plant phenology, productivity and reproduction

Dataset DOI: [10.5061/dryad.9ghx3ffxx](https://doi.org/10.5061/dryad.9ghx3ffxx)

## Description of the data and file structure

**The datasets include all raw data from the manuscript:**

Towards rainy high Arctic winters: how experimental icing and summer warming affect tundra plant phenology, productivity and reproduction. 

Mathilde Le Moullec, Anna-Lena Hende, Matteo Petit Bon, Ingibjörg Svala Jónsdóttir, Øystein Varpe, René van der Wal, Larissa Teresa Beumer, Kate Layton-Matthews, Ketil Isaksen and Brage Bremset Hansen.

Published in Journal of Ecology, Accepted on 31 October 2025.

Data contains information measured at the plot level on: soil temperature, soil moisture, air temperature, Normalized Digital Vegetation Index (NDVI), point intercept biomass quantification, flower count and Salix polaris leaf traits and phenology.

**Common column...,