The focus of the YOPP Targeted Observing Periods (TOPs) planned during the MOSAiC experiment is on increasing radiosonde frequency only during episodes of strong interactions between the Arctic and mid-latitudes, i.e. warm air intrusions and cold air outbreaks.
The proposed strategy is:
- Select events for targeted observations between early March 2020 until melt season based on the atmospheric flow situation, aiming at air masses expected to undergo significant transformation that will pass over existing YOPP Supersites, areas probed by aircraft (e.g. AWI Aircraft campaigns with Polar 5), the ARM mobile facility at Northern Norway and Bear Island supporting the Cold Air Outbreaks in the Marine Boundary Layer (COMBLE) project and the MOSAiC ice-camp.
- Focus on additional radiosonde launches on the Atlantic sector of the Arctic where the majority of warm air intrusions and cold air outbreaks occur.
- Execution of a decision system to request the launch of additional radiosondes will be taken by a committee appointed by the YOPP Process Task Team. Participating stations are notified of a Targeted Observing Period (TOP) five days ahead of time with details of requested launches 24 to 48 hours ahead of time.
Please see also information here for TOPs.