AMSR Data Catalog: TB #8211; AMSR web at JAXA Earth Observation Research Center (EORC)

Brightness Temperature, TB (Standard Product)

The brightness temperature (TB) is the basic observable calculated from the antenna temperature of the microwave radiometer. The following three AMSR2 and AMSR-E products are distributed.

Level-1B (L1B) product that contains brightness temperature data for each footprint.

Level-1R (L1R) product that matches the center position and size of each footprint in each frequency band by spatial matching process.

Level-3 (L3) product, which is a gridded version of L1B product.

Unit is Kelvin [K].

Product Overview

Product Name		Brightness Temperature DOI
Product Type		Standard Product
Processing Level		L1 (Swath data ^*2) and L3 (grid data: EQR, PS)
Product ID		Level-1: BTB (L1B), RTB (L1R) Level-3: T06 (L3,6GHz), T07 (L3,7GHz), T10 (L3,10GHz), T18 (L3,18GHz), T23 (L3,23GHz), T36 (L3,36GHz), T89 (L3,89GHz)
Spec. ^*1	Area	Global
	Spatial Resolution	approx. 5 〜 50 km ^*3
	Accuracy Requirement	±1.5 K
	Range	2 〜 340 ℃
Latest Version		AMSR2: ver. 2.2 2016-08-23 release AMSR-E: ver.4 2018-04-02 release
Product Period		AMSR2: July 2012 〜 AMSR-E: July 2002 〜 October 2011
Data Download		Globe Portal System (G-Portal) * "G-Portal" is currently under maintenance. Data is being distributed through the alternative site below until March 31, 2025 (planned). https://repo.gportal.jaxa.jp/standard/GCOM-W/GCOM-W.AMSR2/
Data Format		HDF5 AMSR2 Level-1 Format 617KB
Quality Flag		L1 TB Quality Flag (PDF 65 page) 617KB
Calibration		ver.2.2 release note 83KB 2016-08-18 AMSR2 Level 1R Product (doi: 10.1109/TGRS.2015.2465170)2016-01-12 Intercomparison results between AMSR2 and TMI/AMSR-E/GMI 723KB 2015-03-26 AMSR2 L1A, L1B, L1R product 2.3MB 2015-03-25

The specifications are defined in the AMSR2 Mission Requirement. The required accuracy is the standard accuracy of standard product defined in the mission requirement.
Swath data is a format in which data for each footprint is stored in a two-dimensional array (observation points in scanning direction x number of scanning lines) in order of observation time.
The spatial resolution of brightness temperature (footprint size) varies depending on the observation frequency band. Reference: AMSR2 channel list

Reference

GCOM-W AMSR2 L1R: Maeda,T., et al., 2016, https://doi.org/10.1109/TGRS.2015.2465170

Revision History

April 2, 2018

AMSR-E Standard product Level-1 ver. 4

Compliant with AMSR2 HDF5 format

Extension of swath width from 196 points to 243 points

Calibration method change with HTS

Geometric parameter correction

Scanning bias correction

New product: AMSR-E L1R release

August 23, 2016

AMSR2 Standard Product Leve-1 ver. 2.2

RFI flag added

ver.2.2 release note

83KB

2016-08-18

April 3, 2015

AMSR2 Standard product Level-1 ver. 2.1

GCOM-W AMSR2 L1R Product(doi: 10.1109/TGRS.2015.2465170)2016-01-12

March 26, 2015

AMSR2 Standard product Level-1 ver. 2.0

Results of intercalibration between AMSR2 and TMI/AMSR-E

723KB

2015-03-26

Status of AMSR2 Level-1 Product

2.3MB

2015-03-25

Back Number

▸

March 1, 2013

AMSR2 Standard product Level-1 ver. 1.11

Results of intercalibration between AMSR2 and TMI/AMSR-E

508KB

2014-05-08

AMSR2 L1R Product

2.6MB

2013-04-08

Results of intercalibration between AMSR2 and TMI/AMSR-E

219KB

2013-04-05

January 25, 2013

AMSR2 Standard product Level-1 ver. 1.1

September 29, 2011

AMSR-E Standard product Level-1 ver. 3

March 1, 2005

AMSR-E Standard product Level-1 ver. 2

June 18, 2003

AMSR-E Standard product Level-1 ver. 1

Data Catalog
TB
TB in slow rotation mode

Brightness Temperature, TB in slow rotation mode (Research Product)

TB in slow rotation mode is not a normal product. It is distributed for researchers.

Product Overview

The slow rotation brightness temperature data are brightness temperature data acquired after AMSR's routine observations were terminated on October 4, 2011, and observations were resumed in slow rotation mode. The main purpose of this data is for cross-calibration with AMSR2. The observation period is from December 4, 2012 to December 4, 2015.

In the steady-state observation (scientific observation mode), the antenna rotation speed is 40 revolutions per minute, but in the slow rotation mode, the antenna rotation speed is reduced to 2 revolutions per minute, so the observation interval and quality of the data are different from those of the steady-state observation. For this reason, the data is produced and distributed as a research product, distinguished from the standard product.

Please note that this data is mainly intended for users and others who are trying to cross-calibrate AMSR-E and AMSR2 or to study new features at low rotation speeds, such as dense sampling, for example.

Main Feature

With slow rotation, the observed area is sparse like dash line (see Fig-1). But on its line at very locally, observed points are positioned with finer-samplings with overlapped foot prints.

Thermal condition with slow rotation is different from that with normal rotation speed. HTS Temperature with slow rotation is higher than normal rotation during satellite daytime by 2-3 kelvin (see Fig-2). So the radiometric correction method used for 40rpm observation may not work well with 2rpm observation for the inexperienced HTS temperature rang.

Fig.1: Observed area with slow rotation

Fig.2: HTS Thermal Equilibrium Condition

Geometric and radiometric correction methods are mainly same as normal rotation but different at following points:

AMSR2 Level 3 Daily Brightness Temperature products are used to remove the ground radiation effect on Cold Sky Mirror at 6GHz instead of AMSR-E self observed brightness temperature.

Correction parameters for bias value at scan start caused by satellite body was updated.

How to use

You can download AMSR-E Slow Rotation Data from following site.

GCOM-W Research Product

Some scenes has quality problem. Check following list before use.

Quality List

16KB

Data format is HDF4. The detail is described on following document.

AMSR-E Slow Rotation Data Format Description Document

1.3MB

The data from December 5, 2012 to December 4, 2015 are available.

Update history

Jan. 19, 2016 Data from November, 2015 to December, 2015 are released.

Back Number

▸

Dec. 4, 2015 JAXA has completed operation of the AMSR-E.

Nov. 13, 2015 Data on October, 2015 are released.

Oct. 7, 2015 Data on September, 2015 are released.

Sep. 11, 2015 Data on August, 2015 are released.

Aug. 19, 2015 Data on July, 2015 are released.
Please note that the Brightness Temperature of 89GHz B-horn V-pol is not correct because the HTS saturation has been unavoidable since July 15th, 2015.

Jul. 8, 2015 Data on June, 2015 are released.

Jun. 11, 2015 Data on May, 2015 are released.

Jun. 3, 2015 Data from March, 2015 to April, 2015 are released.

Apr. 1, 2015 Data observed on August 23, 2013 (Scene ID is P1AME130823102MA) was revised because of 0.03 degree attitude error.

Apr. 1, 2015 Data from December, 2014 to February, 2015 are released.

Dec. 19, 2014: Data on November 2014 are released.

Dec. 8, 2014: Data on October, 2014 are released.

Oct. 21, 2014: Data on September, 2014 are released.

Oct. 6, 2014: Data on August, 2014 are released.

Sep. 5, 2014: Data on July, 2014 are released.

Jul. 30, 2014: NG scenes with geolocation processing problem are revised and released.

Jul. 11, 2014: Data on June, 2014 are released.

Jun. 17, 2014: Data on May, 2014 are released.

May 22, 2014: Data from March, 2014 to April, 2014 are released.

Apr. 21, 2014: Data from March, 2013 to February, 2014 are released.

Dec. 2, 2013: Data from December, 2012 to February, 2013 are released.