Sea surface temperatures are monitored at lighthouse stations along the BC coastline. Average annual sea surface temperatures have warmed between 0.6 to 1.4⁰C per century across the coast of BC . This rate is similar to the global average of 1.1⁰C per century [10,32], although there is significant variation along the BC coast in that some areas have warmed by up to 2.2⁰C per century (e.g. Strait of Georgia, Entrance Island) .
In BC waters, recent sea surface temperature trends have been the result of the interaction of three things: climate change warming, El Niño effects (2015-2016), and the ‘warm blob’ phenomenon (2013-2016) where a large area of very warm water (3⁰C warmer than usual) settled off the BC coast [13,45]. In 2016, average sea surface temperatures were 1-2⁰C warmer than the historical average within the Northeastern Pacific Ocean . The average daily sea surface temperature anomaly was higher in 2016 according to both lighthouse station data (0.98⁰C ± 0.33⁰C) and weather buoy data (0.7⁰C average) as compared to the 22-year historical average (1989-2010), which reflects the long term warming trend .