WP2 net meta data from F/V Great Pacific GP0108, GP0207-01, GP0207-02 in the Coastal Gulf of Alaska, Northeast Pacific from 2001-2002 (NEP project)

<p><strong>Gulf of Alaska - LTOP<br /> WP2 net - meta data, 2001-2002</strong></p> <p>PI: all tows are vertical hauls, 253-micron mesh.</p> <p><strong>GLOBEC 2000: Gulf of Alaska Long-Term Observation Program</strong><br /> <em>T. Weingartner, L. Haldorson, R. Hopcroft, K. Coyle, T. E. Whitledge (all at University of Alaska, Fairbanks), T. Royer (Old Dominion University)</em></p> <p>This project is to conduct the Gulf of Alaska Long-Term Observation Program (GOA-LTOP) as part of Phase II of the Northeast Pacific (NEP) GLOBEC program. The GOA shelf supports a rich ecosystem that includes many commercially important fisheries. The basis for this productivity is enigmatic for the GOA shelf is deep, forced by downwelling-favorable winds, and fed by a massive nutrient-poor coastal freshwater discharge. Both the winds and the freshwater discharge are intimately linked to the strength and position of the Aleutian Low. The GOA ecosystem experiences substantial physical and biological changes on decadal and interannual time scales. Although some of these changes are correlated with various climatic indices a mechanistic understanding of climate change and ecosystem response is unavailable. The generic goal of this LTOP is to understand and quantify temporal (seasonal and interannual) and spatial (cross- and along-shelf) variations in the thermohaline, chemical, and biological properties and relationships of this shelf. Our proposal supports GLOBEC goals that will help: 1) retrospective studies interpret historical data, 2) design a cost-effective long-term monitoring program, 3) provide the seasonal and interannual context for concurrent mesoscale and process studies, and 4) provide boundary conditions and data sets for model evaluation. This 5-year project entails 4 field years and a fifth year for data analyses and synthesis. The field effort involves seven, 9-day interdisciplinary cruises/year in the northern GOA. The study area encompasses the 220-km long, Seward Line (sampled in the 1970s) that extends across the shelf and slope and high resolution sampling of the Alaska Coastal Current (ACC), upstream, downstream, and within Prince William Sound. The ACC is an important shelf habitat for yoy salmon migrating from nursery areas in the sound and into the GOA. The sampling effort (Table A) is year-round and motivated by seasonally significant physical and biological events affecting yoy pink salmon.</p> <p><strong><em>Table A. Sampling schedule and rationale for GOA-LTOP. (Key for Winds, Discharge and Stratification: S=strong; M=moderate; W=weak; D=downwelling winds; U=upwelling winds; V=variable; L=low; H=high) Deep water moves onshore during the July-August upwelling period.</em></strong></p> <table border=\"1\"> <tbody> <tr> <th colspan=\"1\" rowspan=\"2\">Month</th> <th colspan=\"4\" rowspan=\"1\">Sampling</th> <th colspan=\"3\" rowspan=\"1\">Physical Rationale</th> <th colspan=\"1\" rowspan=\"2\">Biological Rationale</th> </tr> <tr> <td>CTD</td> <td>Nutrients</td> <td>Zoo</td> <td>Fish</td> <td>Winds</td> <td>Disch</td> <td>Strat</td> </tr> <tr> <td>March</td> <td>X</td> <td>X</td> <td>X</td> <td>&nbsp;</td> <td>D S</td> <td>L</td> <td>W</td> <td>Zooplankton migrate from depth (at shelfbreak); transported inshore.</td> </tr> <tr> <td>April</td> <td>X</td> <td>X</td> <td>X</td> <td>&nbsp;</td> <td>D M</td> <td>L-M</td> <td>W V</td> <td>Phytoplankton bloom</td> </tr> <tr> <td>May</td> <td>X</td> <td>X</td> <td>X</td> <td>&nbsp;</td> <td>D M-W</td> <td>M</td> <td>M V</td> <td>Maximum oceanic copepod biomass.</td> </tr> <tr> <td>July</td> <td>X</td> <td>X</td> <td>X</td> <td>X</td> <td>D/U W</td> <td>M-H</td> <td>S</td> <td>Maximum zooplankton abundance; YOY salmon enter shelf.</td> </tr> <tr> <td>August</td> <td>X</td> <td>X</td> <td>X</td> <td>X</td> <td>D/U W</td> <td>M-H</td> <td>S</td> <td>Maximum YOY salmon abundance on shelf.</td> </tr> <tr> <td>October</td> <td>X</td> <td>X</td> <td>X</td> <td>X</td> <td>D S</td> <td>H</td> <td>H</td> <td>YOY salmon on shelf.</td> </tr> <tr> <td>December</td> <td>X</td> <td>X</td> <td>X</td> <td>&nbsp;</td> <td>D S</td> <td>M</td> <td>M</td> <td>Fall-winter pre-conditioning for spring nutrients, small zooplankton.</td> </tr> </tbody> </table> <p>The sampling protocol follows GLOBEC guidelines and uses gear types and techniques similar to those in the Oregon LTOP that is also a part of the NEP-GLOBEC program. Most of the research will be conducted from the R/V <em>Alpha Helix</em>. Fish sampling will be done from a chartered trawler in July, August, and October. Both vessels will work together during these cruises so that the fishing charter can verify fish targets detected on the acoustics array towed from the <em>Alpha Helix</em>.</p> <p><em>This page was last updated on September 22, 2000.<br /> Maintained by:<br /> <a href=\"mailto:[e-mail]\">Hal Batchelder [[e-mail]</a><br /> College of Oceanic &amp; Atmospheric Sciences<br /> Oregon State University<br /> Corvallis, OR 97331-5503<br /> phone: [phone]; FAX [phone] </em></p><p><strong>阿拉斯加湾——长期观测计划（Long-Term Observation Program, LTOP）<br />WP2 网——元数据，2001—2002年</strong></p> <p>项目负责人：所有拖网均为垂直拖曳，网目尺寸253微米。</p> <p><strong>全球海洋生态系统动力学研究（Global Ocean Ecosystem Dynamics, GLOBEC）2000：阿拉斯加湾长期观测计划（Gulf of Alaska Long-Term Observation Program, GOA-LTOP）</strong><br /><em>T. Weingartner、L. Haldorson、R. Hopcroft、K. Coyle、T. E. Whitledge（均任职于阿拉斯加大学费尔班克斯分校），T. Royer（奥多明尼昂大学，Old Dominion University）</em></p> <p>本项目作为东北太平洋（Northeast Pacific, NEP）全球海洋生态系统动力学研究计划第二阶段的一部分，旨在实施阿拉斯加湾长期观测计划。阿拉斯加湾陆架拥有丰富的生态系统，孕育了众多具有重要商业价值的渔业资源。该陆架高生产力的成因至今仍不明朗：陆架水体较深，受有利于下降流的风场驱动，且由大量营养匮乏的沿岸淡水径流补给。风场与淡水径流均与阿留申低压（Aleutian Low）的强度和位置密切相关。阿拉斯加湾生态系统在年代际和年际尺度上会发生显著的物理与生物变化。尽管部分变化与多种气候指数存在相关性，但目前尚未形成气候变化与生态系统响应的机制性认知。本长期观测计划的总体目标是理解并量化该陆架的温盐、化学及生物属性及其相互关系在时间（季节与年际）和空间（跨陆架与沿陆架）尺度上的变化特征。本项目支持全球海洋生态系统动力学研究的目标，具体可助力以下工作：1）通过回顾性研究解读历史观测数据；2）设计兼具成本效益的长期监测方案；3）为同期开展的中尺度过程研究提供季节与年际尺度的背景依据；4）为模式验证提供边界条件与数据集。本项目为期5年，包含4个野外作业年与1个数据整理与综合分析年。野外作业计划每年在阿拉斯加湾北部开展7次为期9天的多学科科考航次。研究区域涵盖全长220公里、曾于20世纪70年代开展过采样的苏厄德断面（Seward Line），该断面横跨陆架与陆坡；同时还包括阿拉斯加沿岸流（Alaska Coastal Current, ACC）的上下游以及威廉王子湾（Prince William Sound）内部的高分辨率采样区域。阿拉斯加沿岸流是当年生鲑鱼（Young of the Year, YOY salmon）从威廉王子湾育苗场迁移至阿拉斯加湾的重要陆架栖息通道。本次采样工作（详见附表A）全年开展，采样设计围绕影响当年生粉红鲑的季节性关键物理与生物过程制定。</p> <p><strong><em>附表A. 阿拉斯加湾长期观测计划采样计划与依据。（风场、径流与层化参数说明：S=强；M=中等；W=弱；D=下降流型风场；U=上升流型风场；V=多变；L=低；H=高） 7—8月上升流时段会有深层水向岸输送。</em></strong></p> <table border="1"> <tbody> <tr> <th colspan="1" rowspan="2">月份</th> <th colspan="4">采样项目</th> <th colspan="3">物理过程依据</th> <th colspan="1" rowspan="2">生物学过程依据</th> </tr> <tr> <td>温盐深剖面仪（Conductivity-Temperature-Depth, CTD）</td> <td>营养盐</td> <td>浮游动物</td> <td>鱼类</td> <td>风场</td> <td>径流</td> <td>层化</td> </tr> <tr> <td>3月</td> <td>✔</td> <td>✔</td> <td>✔</td> <td>—</td> <td>D S</td> <td>L</td> <td>W</td> <td>浮游动物从陆架坡折处的深处向岸迁移。</td> </tr> <tr> <td>4月</td> <td>✔</td> <td>✔</td> <td>✔</td> <td>—</td> <td>D M</td> <td>L-M</td> <td>W V</td> <td>浮游植物水华</td> </tr> <tr> <td>5月</td> <td>✔</td> <td>✔</td> <td>✔</td> <td>—</td> <td>D M-W</td> <td>M</td> <td>M V</td> <td>海洋桡足类生物量达到峰值。</td> </tr> <tr> <td>7月</td> <td>✔</td> <td>✔</td> <td>✔</td> <td>✔</td> <td>D/U W</td> <td>M-H</td> <td>S</td> <td>浮游动物丰度达到峰值；当年生鲑鱼进入陆架。</td> </tr> <tr> <td>8月</td> <td>✔</td> <td>✔</td> <td>✔</td> <td>✔</td> <td>D/U W</td> <td>M-H</td> <td>S</td> <td>陆架上当年生鲑鱼丰度达到峰值。</td> </tr> <tr> <td>10月</td> <td>✔</td> <td>✔</td> <td>✔</td> <td>✔</td> <td>D S</td> <td>H</td> <td>H</td> <td>陆架上存在当年生鲑鱼。</td> </tr> <tr> <td>12月</td> <td>✔</td> <td>✔</td> <td>✔</td> <td>—</td> <td>D S</td> <td>M</td> <td>M</td> <td>为春季营养盐循环与小型浮游动物提供秋冬预适应条件。</td> </tr> </tbody> </table> <p>本采样方案遵循全球海洋生态系统动力学研究的规范，所用设备与技术与同样隶属于东北太平洋全球海洋生态系统动力学研究计划的俄勒冈州长期观测计划一致。大部分科考工作将在<em>Alpha Helix</em>号研究船上开展。鱼类采样将在7、8、10月通过租用的拖网渔船完成。在上述航次中，两艘船将协同作业，以便通过拖网渔船验证<em>Alpha Helix</em>号拖曳的声学阵列所探测到的鱼类目标。</p> <p><em>本页面最后更新于2000年9月22日。<br />维护人：<br /><a href="mailto:[e-mail]">Hal Batchelder [[e-mail]]</a><br />海洋与大气科学学院<br />俄勒冈州立大学<br />科瓦利斯，俄勒冈州97331-5503<br />电话：541-737-4500；传真：541-737-2064</em></p>