Joint Seminar: The projected changes in the spatial and temporal scales of the mid-latitude flow
Mid-latitude atmospheric waves set the weather and climate in the extra-tropics, as they largely affect the distribution of heat, moisture, and momentum across the extra-tropics from daily to multi-decadal timescales. The intensity and position of these waves are projected to change considerably by the end of this century, which will result in significant societal impacts in the extra-tropics. However, to date, most previous studies have investigated the future changes in atmospheric waves by integrating waves with different length scales and periods, thus not accounting for the possibility that different waves will respond differently to anthropogenic emissions. I will present two examples where we reexamined the mid-latitude flow response to anthropogenic emissions by separately analyzing the response of different spatial and temporal scales. First, we find that a scale-dependent response of atmospheric waves is evident in temperature variability in the Southern Hemisphere, which includes a shift, in coming decades, towards spatially larger and less persistent temperature anomalies and extreme heat events. Next, by separating large- and small scale-waves in boreal winter, we find that throughout the mid-latitudes large-scale waves are projected to intensify and emerge from the internal variability over the 21st century. In some regions, we find a projected weakening of small-scale waves that obscures the emergence of the waves when accounting for waves of all sizes. Our results emphasize the importance of investigating the scale-dependent changes in the mid-latitude climate, to prevent masking the different impacts of various length scales and periods, and thus provide more accurate climate projections for the mid-latitudes.
Datum
27.11.2024
Uhrzeit
13:30–15:00 h
Ort
- Bundesstr. 53, room 022/023
- Seminar Room 022/023, Ground Floor, Bundesstrasse 53, 20146 Hamburg, Hamburg