Seasonal trends and phenology shifts in sea surface temperature on the North American northeastern continental shelf

Elementa: Science of the Anthropocene

Nicholas R. Record¹  Katherine E. Mills²  Andrew J. Pershing²  Michael A. Alexander³  Kevin D. Friedland⁴  Ryan Weatherbee⁵  Andrew C. Thomas⁵  M. Elisabeth Henderson⁶  Janet A. Nye⁶ 

[1] Bigelow Laboratory for Ocean Sciences, East Boothbay, Maine;Gulf of Maine Research Institute, Portland, Maine;NOAA Earth System Research Laboratory, Boulder, Colorado;National Marine Fisheries Service, Narragansett, Rhode Island;School of Marine Sciences, University of Maine, Orono, Maine;School of Marine and Atmospheric Sciences, Stony Brook University, Stony Brook, New York;

关键词: sea surface temperature;    trends;    phenology;    seasonal cycles;    US northeastern continental shelf;   

DOI  :  10.1525/elementa.240

来源: DOAJ

【 摘 要 】

The northeastern North American continental shelf from Cape Hatteras to the Scotian Shelf is a region of globally extreme positive trends in sea surface temperature (SST). Here, a 33-year (1982–2014) time series of daily satellite SST data was used to quantify and map spatial patterns in SST trends and phenology over this shelf. Strongest trends are over the Scotian Shelf (>0.6°C decade–1) and Gulf of Maine (>0.4°C decade–1) with weaker trends over the inner Mid-Atlantic Bight (~0.3°C decade–1). Winter (January–April) trends are relatively weak, and even negative in some areas; early summer (May–June) trends are positive everywhere, and later summer (July–September) trends are strongest (~1.0°C decade–1). These seasonal differences shift the phenology of many metrics of the SST cycle. The yearday on which specific temperature thresholds (8° and 12°C) are reached in spring trends earlier, most strongly over the Scotian Shelf and Gulf of Maine (~ –0.5 days year–1). Three metrics defining the warmest summer period show significant trends towards earlier summer starts, later summer ends and longer summer duration over the entire study region. Trends in start and end dates are strongest (~1 day year–1) over the Gulf of Maine and Scotian Shelf. Trends in increased summer duration are >2.0 days year–1 in parts of the Gulf of Maine. Regression analyses show that phenology trends have regionally varying links to the North Atlantic Oscillation, to local spring and summer atmospheric pressure and air temperature and to Gulf Stream position. For effective monitoring and management of dynamically heterogeneous shelf regions, the results highlight the need to quantify spatial and seasonal differences in SST trends as well as trends in SST phenology, each of which likely has implications for the ecological functioning of the shelf

【 授权许可】

Unknown