A climatology of the California Current System from a network of underwater gliders
A climatology of the California Current System from a network of underwater gliders
复制标题
来自水下滑翔机网络的加州洋流系统的气候学
DOI：
10.1016/j.pocean.2017.03.002
复制
发表时间：
2017
影响因子：
4.1
通讯作者：
R. Davis
中科院分区：
文献类型：
--
作者：
D. Rudnick;K. Zaba;R. Todd;R. Davis
自主水下滑翔机提供了持续观测沿海海洋的可能性。自2006年以来，加州水下滑翔机网络（CUGN）的Spray水下滑翔机沿着加州合作海洋渔业调查（CalCOFI）66.7、80.0和90.0线进行了调查，据我们所知，这是世界上持续时间最长的滑翔机网络。在这个网络中，滑翔机在水面和500米之间潜水，在3小时内完成一个周期，在此期间覆盖3公里。部分延伸到离岸350-500公里，需要2-3周的时间才能占领。测量的变量包括压力、温度、盐度和深度平均速度。CUGN已经积累了超过10，000个滑翔机日，覆盖超过210，000公里，超过95，000次潜水。这些数据用于产生气候学，其产品是每个变量的平均场、年周期和年周期的异常。分析包括加权最小二乘拟合，以得出平均值和年周期，以及一个客观的地图，以产生异常。最终结果是矩形网格上的深度、离岸距离和时间变量。平均场是横跨加州海流系统主要水流的精细解析剖面，包括极向加州暗流和赤道向加州海流。年周期显示出从表层到温跃层的阶段变化，反映了表层空气/海洋通量和温跃层上升流的影响。年际异常的研究重点是过去十年的气候事件，包括2009-2010年厄尔尼诺，2010-2011年拉尼娜，2014-2015年的温暖异常，以及2015-2016年厄尔尼诺。
Autonomous underwater gliders offer the possibility of sustained observation of the coastal ocean. Since 2006 Spray underwater gliders in the California Underwater Glider Network (CUGN) have surveyed along California Cooperative Oceanic Fisheries Investigations (CalCOFI) lines 66.7, 80.0, and 90.0, constituting the world’s longest sustained glider network, to our knowledge. In this network, gliders dive between the surface and 500 m, completing a cycle in 3 h and covering 3 km in that time. Sections extend 350–500 km offshore and take 2–3 weeks to occupy. Measured variables include pressure, temperature, salinity, and depth-average velocity. The CUGN has amassed over 10,000 glider-days, covering over 210,000 km with over 95,000 dives. These data are used to produce a climatology whose products are for each variable a mean field, an annual cycle, and the anomaly from the annual cycle. The analysis includes a weighted least-squares fit to derive the mean and annual cycle, and an objective map to produce the anomaly. The final results are variables on rectangular grids in depth, distance offshore, and time. The mean fields are finely resolved sections across the main flows in the California Current System, including the poleward California Undercurrent and the equatorward California Current. The annual cycle shows a phase change from the surface to the thermocline, reflecting the effects of air/sea fluxes at the surface and upwelling in the thermocline. The interannual anomalies are examined with an emphasis on climate events of the last ten years including the 2009–2010 El Niño, the 2010–2011 La Niña, the warm anomaly of 2014–2015, and the 2015–2016 El Niño.