Current Conditions of the Northeast Shelf Ecosystem - Thermal Transition Date :: Ecosystems Dynamics and Assessment

Spring Thermal Transition Date

Phenology is the climate influence on the timing between plant and animal production cycles. Many marine organisms time their reproductive cycles to best utilize seasonal phytoplankton blooms, like the spring bloom, and in turn temperature plays a role in the development of the spring bloom. One measure to characterize the change in the timing of thermal forcing is the date of arrival of a spring transition temperature, which will vary by region and is meant to mark the average temperature between winter and summer. The date of arrival of the spring thermal transition temperature was relatively constant since 1982 to approximately 2006 for the Northeast Shelf as a whole and its constituent ecoregions (see figures ). Since 2006, spring transition date has advanced on the order of two weeks. The 2016 spring transition dates continue the trend of early spring transition seen in recent years.