Paleoclimate of Extreme Events

Wed, 08 Apr 2026, 17:00 CEST

Conveners: Alessio Rovere & Alberto Reyes

How rare are truly rare climate extremes? This session uncovers how paleoclimate archives and climate models together expose the full spectrum of hydroclimatic risk – past, present, and future – from hurricane overwash preserved in coastal sediments to centuries-long megadroughts revealed by proxy networks.

Guest speakers:

• Jessica Pilarczyk (Simon Fraser University, Canada)
• Jason Smerdon (Columbia University, USA)

Holocene paleotempestology: unravelling the link between tropical cyclone activity and climate drivers

Jessica Pilarczyk

A major challenge in forecasting the timing, intensity, and impacts of future tropical cyclones (cyclones, hurricanes, typhoons) to coastal areas is the limited short-term instrumental record that does not capture the full spectrum of inundation events from the frequent, low-magnitude to rare, but intense events. Further, as the Earth's climate continues to warm, understanding the climatic driving mechanisms responsible for modulating storm activity over sufficiently long timescales is of paramount importance. Climate models project an increase in the frequency of intense tropical cyclones, as well as a poleward migration in the latitude of their peak intensity, heightening the risk of storm hazards for a greater number of coastal areas, yet few long-term reconstructions of tropical cyclones exist. Fortunately, geological investigations using sediments transported to the coast by landfalling hurricanes (i.e., overwash deposits) are a means for expanding the age range for investigation so that risk assessments are better informed and connections between storm variability and other factors, such as climate drivers, may be properly assessed.

Mega-Effort: 20 years of work on characterizing and explaining megadroughts and megapluvials across the globe

Jason Smerdon

Over the 20-year history of Climate of the Past, the paleoclimate community has worked expansively to develop Common Era reconstructions of past multidecadal drought and pluvial periods known as megadroughts and megapluvials. These reconstruction efforts have been joined by modeling and climate dynamics studies that have sought to understand how such periods come to pass and how their incidence and severity will be influenced in the future. This talk will review work on mega-hydroclimatic events of the past and how they have been coupled with developments in climate modeling that have allowed causal insights. It will begin with a focus on the origins of megadrought studies in southwestern North America before expanding to a more general characterization of how technological developments have allowed us to understand multidecadal hydroclimate events globally, their common drivers, and evidence for sychonous mega-hydroclimatic events that arise through these common origins. The reflection will conclude with a discussion about remaining challenges in our study of these socially impactful and costly events.