Geography Seminar:
Climate Extremes in the Tree-Ring Record

Abstract: 

The frequency and severity of climate extremes are likely to change in a warming climate. Because the timing and spatial extent of pre-instrumental climate extremes such as droughts and floods are used to understand their driving forces and to validate climate models, delineating paleoclimate patterns is vital for deciphering the past and for future planning. Tree-ring records, which are abundant, have annual resolution, and are strongly connected to climate conditions, are one of the most commonly used paleoclimate data sources for understanding past climate. However, the timing and form of precipitation is not always matched well with the recording period in trees. This is particularly true on the North American West Coast, where atmospheric river events can provide 30-50% of annual precipitation in just a few storms. In this talk, I will discuss the challenges of extracting information on climate extremes from tree-ring records. I will present my recent research showing that there is strong potential to improve these records through a focus on extreme capture and by incorporating other metrics that can be measured in trees. I will also discuss how the incorporation of information from other types of paleoclimate data sources and the use of data assimilation techniques can aid our interpretation of past climate and help us understand changes in climate extremes.