The core period of YOPP, which will take place from mid-2017 to mid-2019, will entail periods of enhanced observational and modelling campaigns in both the Arctic and the Antarctic. As a direct outcome of the YOPP planning meetings on "YOPP in the Southern Hemisphere" (June 2016, Columbus, Ohio, USA), and on "Arctic Observations and the YOPP Modelling Component" (both in September 2016, Reading, UK), Special Observing Periods (SOPs) will be carried out during YOPP. The purpose of the SOPs is to enhance the routine observations in an attempt to close the gaps in the conventional Arctic and Antarctic observing systems for an extended period of time (several weeks). This will allow carrying out subsequent forecasting system experiments aimed at optimising observing systems in the polar regions and providing insight into the impact of better polar observations on forecast skills in lower latitudes.
It has been decided to have the following three Special Observing Periods (click to enlarge
figure on the right):
- February 1st to March 31st, 2018 in the Arctic,
- July 1st to September 30th, 2018 in the Arctic, and
- November 16th, 2018 to February 15th, 2019 in the Antarctic.
A fourth Special Observing Period in the Arctic takes place February 1st to March 31st, 2020, aligned with the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) – the first year-round expedition in the central Arctic that will provide a quantum leap in our understanding of critical Arctic processes and their representation in weather and climate models.
What can be done during the SOPs?
Firstly, it is critical that as many observations as possible will be shared through the WMO Global Telecommunication System (GTS) to make them accessible to operational prediction centres. Secondly, it will be important to enhance the current observation network by: a) more frequent observations from existing platforms and/or b) adding observations in regions where the observation network is not sufficiently dense.
On the following subpages we provide impressions of the additional observational efforts which have been done during the SOPs.