Figure 2
From: Marine heatwaves and the collapse of marginal North Atlantic kelp forests
Details of MHW events based on long-term temperature records from subsurface temperature loggers (a,b) and satellite-derived SST measures (c,d). Black lines show 2018 temperatures. Green lines are the MHW threshold temperature, calculated using the 90th percentile above the 30-year climatology record (blue line). Dashed line indicates lethal temperature threshold for sugar kelp. Maps in bottom panels show spatial extent of the 2018 MHW event around S. Norway (e) and E. USA (f) study areas (blue circles) at the time of maximum temperature in (a,b). Maps were generated in R using the HeatwaveR package (R Core Team, https://www.R-project.org, R package version 0.4.4, https://CRAN.R-project.org/package=heatwaveR), and the marine heatwave tracker68,71. Events are categorized into the four classes of MHW severity.
