Fall 2013 Update: Spring Bloom Start Day and Magnitude
The spring bloom typically starts earlier in the more southern segments of the Northeast Shelf LME.
In 2013, no bloom start date could be detected for the Northeast Shelf as a whole and bloom magnitude based on a climatological bloom period was lower than recent years (see NES figure). Spring bloom magnitude is one measure of bloom dimension and is calculated as the sum of chlorophyll concentrations during the bloom period.
A more dramatic change in bloom dynamics occurred in the Gulf of Maine where bloom start day went from the earliest recorded bloom start in 2012 to the latest recorded start in 2013 (see GOM figure). The Gulf of Maine bloom magnitude was the lowest of the time series.
Finally, the Middle Atlantic Bight bloom started at around day 100, but since so few spring bloom have been detected in this area, it is hard to assess the significance of the this particular bloom start (see MAB figure). This analysis was based on a blended time series of MODIS and SeaWiFS remote sensing data that utilized a time and area correction between the two sensors.