Talk abstract:
This presentation will focus on observations, processes and variability in the Labrador Sea and various aspects of oceanic seasonality, especially with respect to interpreting shipboard observations and making conclusions about longer-term changes in the upper ocean and below. The present chapter of the North Atlantic series includes the Labrador Sea’s World Ocean Circulation Experiment (WOCE) line climatology, trends and multiyear cycles of convectively-formed water mass developments, approached with the WOCE-quality full-depth oceanographic observations collected by the Bedford Institute of Oceanography and international partners between the summers of 1990 and 2019 (exactly 30 years!), the year-round 2000 m deep Argo float profiles available for the past 20 years, and Hamilton Bank mooring data since the late 1970s. In particular, we will see how the recent progressive development of winter convection, lasting for seven years (2012-2018), first retreated to shallower depths and then, in 2021, was essentially off the big picture of convective mixing in the Labrador Sea. Causes and reasons of its progressive multiyear deepening and most recent shutdown will be also presented and discussed.