Bridging the gap between an applied map and scientific needs: Visualization of the uncertainty of plant hardiness zone maps, with emphasis on climate change impact

• Published in: Applied geography (Sevenoaks) 2023-05, Vol.154, p.102938, Article 102938
• Main Authors: Bede-Fazekas, Ákos, Somodi, Imelda
• Format: Article
• Language: English
• Subjects: Climate change; Extreme minimum temperature; Frost hardiness; Spatial downscaling; USDA zone; Variability
• ISSN: 0143-6228; 1873-7730
• DOI: 10.1016/j.apgeog.2023.102938

Plant hardiness zone maps (PHZMs) are isometric map representations of the continuous extreme minimum temperature surface that are easy to interpret and widely used. Hardiness zone map can have remarkable uncertainty from several sources, e.g. downscaling, climate variability and intermodel/interscenario variability. A systematic review of the literature was conducted that revealed remarkable gaps in the visual communication of uncertainties, mostly related to downscaling and climate variability. Quantification of uncertainties is a requirement for scientific use. It could make plant hardiness zone maps part of rigorous analyses while also serving as applied maps for agricultural/horticultural decisions. To support the quantification, a handful of thematically grouped and compared tools are presented for visual communication of hardiness zones, their differences and their uncertainties. It was based on the systematic review with special emphasis on climate change impact assessment – a key area of application of PHZMs. It is completed with a case study of, and demonstrational maps for, Hungary. These showed that independent sources of uncertainties reveal different spatial patterns, ranging from 1 to 11 zones, and can accumulate and interact with each other. We concluded that for uncertainty visualization, maps based on the continuous extreme minimum temperature are preferred over those based on plant hardiness zones. •Plant hardiness zone maps can have remarkable uncertainties from several sources.•Visualization of the uncertainties provides their solid scientific foundation.•Visual communication tools of hardiness zones and their uncertainties are reviewed.•Fine resolution demonstrational maps and recommendations complete the review.•Sources of uncertainty reveal different spatial patterns, ranging from 1 to 11 zones.