Climate Change Amplifications of Climate‐Fire Teleconnections in the Southern Hemisphere

Recent changes in trend and variability of the main Southern Hemisphere climate modes are driven by a variety of factors, including increasing atmospheric greenhouse gases, changes in tropical sea surface temperature, and stratospheric ozone depletion and recovery. One of the most important implications for climatic change is its effect via climate teleconnections on natural ecosystems, water security, and fire variability in proximity to populated areas, thus threatening human lives and properties. Only sparse and fragmentary knowledge of relationships between teleconnections, lightning strikes, and fire is available during the observed record within the Southern Hemisphere. This constitutes a major knowledge gap for undertaking suitable management and conservation plans. Our analysis of documentary fire records from Mediterranean and temperate regions across the Southern Hemisphere reveals a critical increased strength of climate‐fire teleconnections during the onset of the 21st century including a tight coupling between lightning‐ignited fire occurrences, the upward trend in the Southern Annular Mode, and rising temperatures across the Southern Hemisphere. Plain Language Summary This paper provides a critical view on the impending fire danger under increased climatic pressures, which is of extreme importance for the immediate future of climate change policy making and of landscape management and conservation actions. Our analysis of documentary fire records from across the Southern Hemisphere reveals, for the first time, a critical increased strength of fire‐climate teleconnections and a tight coupling between lightning‐ignited fire occurrences, the upward trend in the Southern Annular Mode, and rising temperatures during the onset of the 21st century. A clear increase in the potential for lightning‐ignited fires in response to climate change is an important reminder of the multitude of impacts that global warming will wreak on the Earth System. Key Points Climatic change is amplifying climate‐fire teleconnections There is a strong correlation between SAM and fire activity in the Southern Hemisphere Global warming is linked to increased natural (lightning‐ignited) fire occurrence