Remote Sensing of the NE Pacific: Retrospective and Concurrent Time Series Analysis Using Multiple Sensors on Multiple Scales

项目摘要：在东北太平洋的亚北极和亚热带涡旋的边界流内部和之间，有大量的物理和生物变量共同变化。这些(在美国GLOBEC报告17、11和7中总结)包括运输强度、表面温度、浮游动物生物量和具有重要商业价值的鱼类的渔获量。时间尺度从个别事件到十年间的制度转变。这些物理场和生物场共同变化的机制尚不清楚，但据推测，年际变化所涉及的相同机制也影响长期气候变化。因此，澄清和量化管理年际变化的机制将有助于“模拟”这些具有重要经济和生态意义的系统对未来气候变化的生物和物理反应。处理这些时间和空间尺度的可变性及其潜在联系的主要战略之一是有效利用历史上和目前可用的多传感器卫星数据集。这项提议的目标是处理、存档和分析来自若干卫星传感器和其他来源的环境数据，以确定和量化东北太平洋海面输送、温度和色素浓度变化的主要模式。分析将涵盖多个时间/空间尺度，考虑到盆地尺度的联系、边界流特定区域内的中尺度环流以及其中两个区域的小尺度近岸环流。除了在该项目中进行的分析外，这些数据还将通过互联网和光盘提供给其他调查人员。在盆地尺度上，该项目将量化西风漂移(WWD)、阿拉斯加湾沿岸(CGOA)和加州洋流系统(CCS)之间的交换，检验经常使用的假设，即两个边界流的协变性是由于Wood位置的变化。另一种大尺度假设是，这些边界流不是由大尺度风系统强迫的，而是这些大气系统在盆地之间是不同的。卫星高度计和散射计首次提供了检验这一假说的仪器。与卫星数据相比，持续重新分析的大气模式风允许在更长的时间内测试风的协变性。利用EOF分析和典型相关分析，对大尺度的交通变率模式进行量化。在中尺度上，在各边界流范围内，AVHRR海温和/或卫星海洋水色资料与高度计资料相结合，可以分辨出50~100公里尺度的中尺度环流特征。AVHRR和海洋颜色数据的分辨率为1千米，将在该项目的三年(1998-2000)期间以持续方式收集和处理。CCS(25多点55多点N)1981-1997年期间的1公里AVERR历史数据也将以相同的方式处理。这些数据将允许检查美国GLOBEC/COOP研究第二阶段中提议进行过程研究的地点周围的中尺度环流(急流和涡旋的位置和季节性)。沿不列颠哥伦比亚省和美国西北部边界的直接交通也将被检查，以提供更多关于两个环流之间大范围联系的细节。其他重点区域将是：哥伦比亚河羽流周围地区，由于对迁出的科霍鲑鱼的影响；威廉王子湾以西地区，幼年鲑鱼在那里与阿拉斯加河相遇；以及从俄勒冈州中部和南部沿海海洋流入加利福尼亚州洋流核心的详细情况。这项分析将检验这样一种假设，即加州中部数据集中的年际变化大部分来自俄勒冈州附近的上升流区域，而不是来自伍德地区。卫星数据与监测研究期间收集的现场数据(由GLOBEC或其他来源资助)相结合，将用于将卫星环流场转化为质量、热量和色素表面输送。季节过渡的时机将是另一个重点，因为沿海海洋环境状况可能与鲑鱼迁徙不匹配。

PROJECT SUMMARY: A significant number of physical and biological variables covary within and between the boundary currents of the subarctic and subtropical gyres in the NE Pacific Ocean. These (summarized in US GLOBEC Reports 17, 11 and 7) include the strength of the transports, surface temperatures, zooplankton biomass and the catch of commercially important fishes. Time scales range from individual events to interdecadal regime shifts. The mechanisms by which these physical and biological fields covary are unknown, but it is postulated that the same mechanisms involved in interannual variability also affect long term climatic variability. Clarification and quantification of the mechanisms governing interannual variability will therefore help to `model` the biological and physical responses of these economically and ecologically important systems to future climate change. One of the principal strategies for addressing variability across these time and space scales and their potential linkages is to make effective use of historical and presently available multi sensor satellite data sets. The goal of this proposal is to process, archive and analyze environmental data from a number of satellite sensors and other sources in order to characterize and quantify the dominant modes of variability in surface transports, temperature and pigment concentrations in the NE Pacific Ocean. The analyses will cover multiple time/space scales, considering basin scale connections, mesoscale circulation within specific regions of the boundary currents, and small scale, nearshore circulation in two of the regions. In addition to the analysis carried out in this project, these data will be made available over Internet and on CDROM to other investigators. On the basin scale, the project will quantify the exchange between the West Wind Drift (WWD), the Coastal Gulf of Alaska (CGOA) and the California Current System (CCS), testing the often used hypothesis that the covariability in the two boundary currents is due to changes in the location of the WOOD. The alternate large scale hypothesis is that this is not the case that these boundary currents are forced by the large scale wind systems and that these atmospheric systems covary between the basins. Satellite altimeters and scatterometers provide the instruments to test this hypothesis for the first time. Consistently reanalyzed atmospheric model winds allow a test of the wind covariability over a longer period than possible with the satellite data. The largescale modes of transport variability will be quantified using EOF analysis and Canonical Correlat on Analysis. On the mesoscale, within each boundary current, the combination of AVHRR SST and/or satellite ocean color with altimeter data can resolve mesoscale circulation features with scales of 50 100 km or less. AVHRR and ocean color data, with 1 km resolution, will be collected and processed in ongoing fashion for the three years of the project (1998 2000). Historical 1 km AVERR data over the CCS (25Ý 55ÝN) for the period 1981 1997 will also be processed in identical fashion. These data, will allow an examination of the mesoscale circulation (location and seasonality of jets and eddies) around the sites proposed for process studies in Phase II of the US GLOBEC/CoOP study. The direct transport along the boundaries of British Columbia and the Northwest US will also be examined, to provide greater details about the large scale connection between the gyres. Other areas of focus will be: the region around the Columbia River Plume, due to the impact on out migrating Coho salmon; the region west of Prince William Sound, where juvenile salmon encounter the Alaskan Stream; and details of the flow from the coastal ocean along central and southern Oregon into the core of the California Current oflf northern and central California. The analysis will test the hypothesis that much of the interannual variability seen off central California in the CalCOl?I data set comes from the upwelling region off Oregon, rather than from the WOOD. Combination of the satellite data with in situ data collected during monitoring studies (funded by GLOBEC or other sources) will be used to transform the satellite circulation fields into mass, heat and pigment surface transports. Timing of seasoual transitions will be another focus, due to possible mismatches of coastal ocean environmental couditions with salmon out migrations.