Oceanographic atlas of the Seno de Corcubión
Here, a database and an oceanographic atlas are presented sinthesizing all the information extracted from 20 years of oceanographic satellite data focused on the Seno de Corcubión. They have been used to study the time series of three important oceanographic variables: sea surface temperature (SST), chlorophyll a concentration ([Chlo]) and turbidity (K490).
This work was performed in the context of the project CONNECT (CTM2006-09043/MAR) cofunded by the Spanish Ministerio de Educación y Ciencia and the European Regional Development Fund, and in colaboration with Gimena Ingeniería S.L., awardee of project PGIDIT05SIN079E of the Plan Gallego de IDIT (Xunta de Galicia).
Visualization of imagery for coastal oceanographic variables
This web interface provides a gateway to the data and statistical analyses reported in the report “Observing the coastal climate dynamics at multiple temporal and spatial scales using GLMs: new uses for oceanographic satellite data”.
The databases are available for download and use under an Attribution-Non Commercial-Share Alike Creative Commons 3.0 license
The interface has three panels:
– The left pannel is used for the selection of oceanographic variables and temporal navigation; it also allows to switch between the satellite imagery derived from raw data and the smoothed data obtained from the GLM analyses.
Satellite images from Coastal Zone Color Scanner (CZCS), Sea-viewing Wide Field-of-view (SeaWiFS) and Advanced Very High Resolution Radiometer (AVHRR) were provided by Spanish Centro de Recepción, Proceso, Archivo y Distribución de Imágenes de Observación de la Tierra (CREPAD). Sea surface temperature was calculated by multi-channel SST algorithm (McClain et al., 1985), chlorophyll a concentration was calculated using the OC4v4 algorithm defined by O’Reilly (2000) and turbidity was calculated as the diffuse attenuation coefficient of downwelling irradiance at 490 nm (Mueller, 2000). Oceanographic sensors to calculate [Chlo] and turbidity variables were not operative during the period 1987-1997.
– The central panel is used for data display: it shows a map of the study region and an overlay with the grid use to extract the oceanographic information, as codified in the bottom color palette (ranging linearly between the limits shown). Pointing at one pixel with the mouse raises a tooltip showing the exact value of the oceanographic variable displayed at that position. The same tooltip mechanism is used to query the color palette.
The area under scope is the marine area of the Seno de Corcubión (NW Galicia, Spain), covering 300 km2 and with a maximum depth of 100 m . It is located in the westernmost area of Galicia (NW Iberian peninsula), between Rías Baixas (to the South) and Costa da Morte (to the North). This is a very open area with a strong oceanic influence and reduced supply of continental water, only represented by Ézaro River.
A mesh of 78 points with a separation of 1′ between them (coinciding with the center of the pixels of the highest resolution images) and covering all the previously defined subareas was established in the study area. Mixed land-sea pixels from the original data were masked out to be consistent with our working scale. Oceanographic parameters from monthly images were extracted to create a database with the different oceanographic variables representative of the spatial and temporal variability. Each record in the database corresponds to the value of an oceanographic variable in one of the pixels at some given date (month and year).
– The right panel can be used to perform queries on the actual database about the monthly values of the oceanographic variables within any time period, in any subarea and summarized monthly, annually or seasonally. The results are reported in a table that opens in a new window and can be readily copied and pasted to a spreadsheet. The links in the bottom of this pannel also allow the download of the database in portable CSV format, including the GLM-adjusted values of the variables.
The queries allow the researcher or the curious to take advantage of the potential of oceanographic satellite images to study oceanographic conditions in this coastal area at different spatial (per subareas or averaging in the entire region) and temporal scales (month, year, seasonal) interactively.
