Abstract:
Stakeholders express a strong need for reliable information on changes in climate extremes in the recent past and coming decades as a basis for adaptation strategies. Quantifying reliable hazard return periods, an important factor in the risk equation, is vital but remains challenging because extremes are very rare by definition and occur irregularly due to internal climate variability. Likewise, it is particularly challenging to detect potential local and regional changes in both observations and models. Since observational series are often short, there is a substantial risk of identifying spurious trends, or missing a climate change signal hidden by large variability. Based on a large initial condition ensemble I demonstrate that the latter may lead to too high return period estimates for hot and heavy precipitation extremes in today’s climate. This implies a potential serious underestimation of present-day probabilities of temperature and precipitation extremes.
Since the hazard probability is an important factor in the risk equation, we may regionally substantially underestimate the risk of temperature and precipitation extremes of the coming decades and not be well prepared for the events possible today and in the coming decades.
What is the Joint Oslo Seminar (JOS):
Atmospheric and climate sciences have a stronghold in Oslo among the four institutions University of Oslo, the Meteorological Institute, CICERO and NILU. This joint seminar invites renowned international experts to contribute to an informal series of lectures, meant to create interaction with the Oslo atmospheric and climate science community on recent highlights and analysis in the field. All seminars will be held on Thursdays (Noon -1pm) and lunch (sandwiches) will be served on a “first-come-first-served”-basis.