Seasonal trends and phenology shifts in sea surface temperature on the North American northeastern continental shelf
Seasonal trends and phenology shifts in sea surface temperature on the North American northeastern continental shelf
复制标题
DOI：
10.1525/elementa.240
复制
发表时间：
2017-08
期刊：
影响因子：
--
通讯作者：
A. Thomas;A. Pershing;K. Friedland;J. Nye;Katherine E. Mills;M. Alexander;N. Record;Ryan A. Weatherbee;M. E. Henderson
中科院分区：
文献类型：
--
作者：
A. Thomas;A. Pershing;K. Friedland;J. Nye;Katherine E. Mills;M. Alexander;N. Record;Ryan A. Weatherbee;M. E. Henderson
从哈特拉斯角到苏格兰陆架的北美东北大陆架是全球海温极端正趋势区域。本文使用了33年（1982-2014）的每日卫星海温数据序列来量化和绘制该大陆架海温趋势和物候的空间格局。最强的趋势是在苏格兰大陆架（>0.6°C， 10年-1）和缅因湾（>0.4°C， 10年-1），而在中大西洋湾内部（~0.3°C， 10年-1）的趋势较弱。冬季（1 - 4月）趋势相对较弱，在某些地区甚至为负值；初夏（5 - 6月）趋势均为正趋势，夏末（7 - 9月）趋势最强（~1.0°C 10 -1）。这些季节差异改变了海温周期的许多指标的物候特征。在春季趋势中较早达到特定温度阈值（8°C和12°C）的年份，在斯科舍大陆架和缅因湾最为强烈（~ -0.5天）。定义最温暖夏季的三个指标显示，在整个研究区域，夏季开始时间较早，夏季结束时间较晚，夏季持续时间较长。在缅因湾和斯科舍大陆架上，开始和结束日期的趋势是最强的（~1天/年）。在缅因湾的部分地区，夏季持续时间增加的趋势是每年100多天。回归分析表明，物候趋势与北大西洋涛动、当地春夏季气压和气温以及墨西哥湾流位置有区域变化的联系。为了有效地监测和管理动态异质大陆架区域，研究结果强调需要量化海温趋势的空间和季节差异以及海温物候趋势，每一种趋势都可能对大陆架的生态功能产生影响
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