• Top
  • Learning
  • About AMSR
  • Quick Guide to AMSR
  • AMSR Utilization
  • Enjoy AMSR!
  • About MW Remote Sensing
  • AMSR in the World
  • Retrieval Algorithm
  • Calibration & Validation
  • Reading Materials
  • Publication List
  • Science Plan
  • Related Projects

About AMSR

AMSR-E

AMSR-E

The Advanced Microwave Scanning Radiometer 2 (AMSR2) onboard the GCOM-W satellite is a remote sensing instrument for measuring weak microwave emission from the surface and the atmosphere of the Earth. From about 700 km above the Earth, AMSR2 will provide us highly accurate measurements of the intensity of microwave emission and scattering.

The antenna of AMSR2 rotates once per 1.5 seconds and obtains data over a 1450 km swath. This conical scan mechanism enables AMSR2 to acquire a set of daytime and nighttime data with more than 99% coverage of the Earth every 2 days.

Satellites in operation or under development

  • GOSAT-GW / AMSR3
    The Global Observing SATellite for Greenhouse gases and Water cycle

    GOSAT-GW / AMSR3

    The Advanced Microwave Scanning Radiometer 3 (AMSR3) is the JAXA satellite/sensor currently under development.

    see more
  • SHIZUKU(GCOM-W)
    About Global Change Observation Mission - Water

    "SHIZUKU" (GCOM-W)

    Observing All Environmental Changes on Earth for Present and Future Generations

    see more
Operation Completed missions
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  • Aqua Earth Observation Satellite
    "Aqua" Earth Observation Satellite

    AMSR-E

    An Earth-observation satellite to contribute to the understanding of the Earth's water cycle

    see more
  • Midori II
    Advanced Earth Observation Satellite-II "Midori II"

    ADEOS-II

    The successor of the Advanced Earth Observing Satellite "Midori"(ADEOS) launched in 1996, is also known as Midori II.

    see more
  • Momo-1(MOS-1)
    Marine Observation Satellite-1 "Momo-1" (MOS-1)

    MOS-1/MSR, MOS-1b/MSR

    It was developed as the first Earth observation satellite using Japan's own technology, in response to the need for effective use of Earth resources and environmental conservation.

    see more

Quick Guide to AMSR

AMSR Utilization

  • weather prediction
    Weather Prediction

    Application of Data Acquired by SHIZUKU at Japan Meteorological Agency

    see more
  • weather prediction
    Weather Prediction

    NOAA to utilize data acquired by "SHIZUKU"

    see more
  • Ocean Resources
    Ocean Resources

    JAFIC

    see more

Enjoy AMSR!

Let's Make Paper Craft

  • EOS Aqua 1/50 Scale Model
    EOS Aqua 1/50 Scale Model

    Satellite EOS Aqua

    The Illustrated Assembly Instructions (PDF: 692KB)
    The Model Parts (PDF: 5546KB)
  • Earth Soccer Ball Paper Models
    Earth Soccer Ball Paper Models

    Color Composite

    (PDF: 1.3MB)
  • Earth Soccer Ball Paper Models
    Earth Soccer Ball Paper Models

    Sea Surface Temperature

    (PDF: 913KB)

About Microwave Remote Sensing

Water exists in the natural world in various forms and states, such as clouds, water vapor, and rain in the atmosphere, seawater and sea ice, rivers, soil, vegetation, and snow cover, and circulates with energy exchange. The water molecule H2O, which plays a key role in such water cycle, has a unique property in the microwave band and emits weak microwaves depending on its state, shape, and temperature. AMSR measures such weak microwave signals emitted from the natural world.

Microwave remote sensing
read more
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Microwave Radiation Transfer

Microwaves emitted from the earth's surface are absorbed and scattered by rain, clouds, and water vapor as they pass through the atmosphere, and are attenuated. At the same time, microwaves are also emitted from rain, clouds, and water vapor. There are also a few microwaves that are scattered by raindrops and cloud particles to the direction of the AMSR from other directions. This process of microwave propagation is called radiative transfer.

Microwave radiation transfer

Frequency Characteristics

In the microwave radiative transfer, whether the signal from the atmosphere or from the earth's surface is dominant depends on the frequency band. In general, the surface signal is dominant in the lower frequency bands, while the atmospheric signal is dominant in the higher frequency bands. AMSR has two channels, horizontally polarization and vertically polarization, in each band from 6 GHz low frequency to 89 GHz high frequency. AMSR's multi-frequency and multi-polarization observation data can be used to estimate various water-related meteorological and hydrological quantities, such as rain and water vapor, seawater and sea ice, soil moisture and snow cover.

Frequency characteristics

Microwave Radiometers in the Wold

Microwave radiometers have been launched by meteorological and satellite agencies around the world.

The size of the footprint and the observation width of a microwave radiometer are determined by the size of the antenna and other specifications, as well as the altitude of the satellite. The following graph plots the microwave radiometers of each country in the space of the observation width (horizontal axis) and the footprint of the 36 GHz band (vertical axis). The upper right corner of the graph indicates that the sensor has the highest performance with both resolution and high frequency/wide area observation performance.

Microwave Radiometers in the World
WindSat

DoD USA

MADRAS

ISRO India, France

SSM/I

DoD USA

GMI

NASA USA

SSMIS

DoD USA

MWRI

CMA China

MWRI(HY2)

NSOAS China

AMSR2

JAXA Japan

Retrieval Algorithm

Development and selection of retrieval algorithms for generating geophysical products are being conducted through the algorithm comparison study in cooperation with science team. The same procedure will be continued after launch as needed to improve the algorithm performance.

Descriptions of GCOM-W1 AMSR2 Level 1R and Level 2 Algorithms (Rev.A, Jul. 9, 2013 PDFfile 4.9MB)

Calibration and Validation of AMSR products

Calibration

In a broad sense, calibration activities include pre-launch design and calibration testing, post-launch in-orbit evaluation, and long-term trend monitoring. In orbit, evaluation and analysis using calibration counts, various ancillary data, and deep space calibration data acquired by AMSR2, and inter-comparison with other passive microwave radiometers. To confirm long-term data quality, perform monitoring of temporal changes of these calibration data and sensor characteristics.

Validation

Validation activities aim to evaluate the accuracy of geophysical products by comparing in-situ measurements and AMSR2 estimates. These activities will be implemented by effectively using the operational in-situ observations in cooperation with the worldwide meteorological/oceanographical organizations, and by conducting dedicated field observations for particular geophysical parameters like soil moisture.

Validation Real-Time Monitor

A validation real-time monitor system is here (GCOM-W Validation Web).

Reading Materials

Improving our Understanding of Climate Change - Observing our Water Planet using AMSR and AMSR-E -

Publication List

see more

Science Plan

Grand Plan for Water Cycle Observation by Satellite

Related Projects

  • GCOM-C
    Global Change Observation Mission - Climate

    GCOM-C

    see more
  • The Global Precipitation Measurement
    The Global Precipitation Measurement

    GPM

    see more
  • Global Satellite Mapping of Precipitation
    Global Satellite Mapping of Precipitation

    GSMaP

    see more