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oce (version 1.1-1)

amsr-class: Class to Store AMSR-2 Satellite Data

Description

This class stores data from the AMSR-2 satellite.

Arguments

Slots

data

As with all oce objects, the data slot for amsr objects is a list containing the main data for the object.

metadata

As with all oce objects, the metadata slot for amsr objects is a list containing information about the data or about the object itself. Examples that are of common interest include longitude and latitude, which define the grid.

processingLog

As with all oce objects, the processingLog slot for amsr objects is a list with entries describing the creation and evolution of the object. The contents are updated by various oce functions to keep a record of processing steps. Object summaries and processingLogShow both display the log.

Modifying slot contents

Although the [[<- operator may permit modification of the contents of amsr objects (see [[<-,amsr-method), it is better to use oceSetData and oceSetMetadata, because that will save an entry in the processingLog to describe the change.

Retrieving slot contents

The full contents of the data and metadata slots of a amsr object named amsr may be retrieved in the standard R way. For example, slot(amsr, "data") and slot(amsr, "metadata") return the data and metadata slots, respectively. The [[,amsr-method operator can also be used to access slots, with amsr[["data"]] and amsr[["metadata"]], respectively. Furthermore, [[,amsr-method can be used to retrieve named items (and potentially some derived items) within the metadata and data slots, the former taking precedence over the latter in the lookup. It is also possible to find items more directly, using oceGetData and oceGetMetadata, but this cannot retrieve derived items.

Details

The Advanced Microwave Scanning Radiometer (AMSR-2) is in current operation on the Japan Aerospace Exploration Agency (JAXA) GCOM-W1 space craft, launched in May 2012. Data are processed by Remote Sensing Systems. The satellite completes an ascending and descending pass during local daytime and nighttime hours respectively. Each daily file contains 7 daytime and 7 nighttime maps of variables named as follows within the data slot of amsr objects: timeDay, SSTDay, LFwindDay (wind at 10m sensed in the 10.7GHz band), MFwindDay (wind at 10m sensed at 18.7GHz), vaporDay, cloudDay, and rainDay, along with similarly-named items that end in Night. See [1] for additional information on the instrument, how to cite the data source in a paper, etc.

The bands are stored in raw form, to save storage. The accessor function [[,amsr-method can provide these values in raw form or in physical units; plot,amsr-method, and summary,amsr-method work with physical units.

References

1. Information on the satellite, how to cite the data, etc. is provided at http://www.remss.com/missions/amsr/.

2. A simple interface for viewing and downloading data is at http://images.remss.com/amsr/amsr2_data_daily.html.

See Also

landsat-class for handling data from the Landsat-8 satellite.

Other things related to amsr data: [[,amsr-method, [[<-,amsr-method, composite,amsr-method, download.amsr, plot,amsr-method, read.amsr, subset,amsr-method, summary,amsr-method