The AMSR-E automatically halted its observations and rotation on October 4, 2011 (UTC) due to increased rotation friction. After then NASA and JAXA began to analyze the situation and had been seeking for the way to restart AMSR-E observation. And on December 4, 2012 (UTC,) the AMSR-E restarted its observations and rotation with slow rotation (2 rotations per minute). JAXA completed initial radiometric and geometric correction for slow rotation data, and now AMSR-E Slow Rotation Data is available to public users.
This data is useful for users who cross-calibrate AMSR-E with other radiometers and who try to research using new feature by slow rotation and so on. This data is not JAXA's standard product. AMSR2 Standard Product is available for general user.

image: Observed area with slow rotation

The detail is described in the following page.

JAXA has been operating the Advanced Microwave Scanning Radiometer-EOS (AMSR-E) for over nine years (despite a design life of three years) as an onboard device installed in the American earth observation satellite Aqua, after its launch on May 4, 2002. It has been contributing accuracy improvement of weather forecasts, compiling ocean condition information for fishing, and understanding the impact of global warming in the field of water circulation and climate change.
Since the end of August, 2011, however, the continuous increase of relatively large antenna rotation friction was detected, thus JAXA has been monitoring the condition. At 3:58 p.m. on October 4, 2011 (Japan Standard Time,) the AMSR-E automatically halted its observations and antenna rotation.
JAXA will continue to analyze this problem, and take necessary measures. We will also launch the successor to the AMSR-E, the Global Change Observation Mission 1st- Water “SHIZUKU" (GCOM-W1.)

On May 15, 2006, the Japan Meteorological Agency started to use data acquired by onboard microwave radiometer sensors on satellites, including the AMSR-E, the Japanese sensor aboard the NASA satellite AQUA, for the global numerical prediction model.

Since Nov. 17, 2004, AMSR-E data has been used for the "meso numerical prediction model," which is used for small scale weather forecasts around Japan. It contributes to improve the forecast accuracy of local phenomena, such as localized heavy rain.

The observation data of the microwave radiometer provided this time includes the vapor volume in the lower atmosphere where observations have not been carried out so far. It is confirmed that the forecast accuracy of the path of a typhoon was improved by using the objective analysis (*1) of the global numerical prediction model.

*1 Objective Analysis
(Japan Meteorological Agency / Written in Japanese)
http://www.jma.go.jp/jma/kishou/know/whitep/1-3-3.html

The graph shows the forecasted path of typhoons at each forecast time. The red line shows the forecast objective analysis with microwave data and the blue line is for that without it. The red line is lower than the blue one most of the time, thus the forecast accuracy is improved by using microwave data. The blue dots are the number of samples used for accuracy verification (Y axis.)

Figure 2 shows observation areas of the five sensors on the five satellites used for the analysis this time. The AMSR-E data (in green) covered oceans that the other satellites could not observe; therefore, the AMSR-E is imperative for covering oceans around the world.

The AQUA turned four years old on May 4, and the AMSR-E is also operating smoothly.

The Japan Meteorological Agency started using data from AMSR-E for its weather forecasting operations on Nov. 17, 2004. In recent years, the most commonly used forecasting method is numerical weather predictions by reproducing the atmospheric movements on a computer. The accuracy of the numerical weather prediction heavily depends on the quality and quantity of observation data and numerical models. Data from a satellite is very important input information for the predictions because a satellite can acquire homogenous data from the vast ocean areas which are otherwise very difficult to observe.

Since Nov. 17, water vapor volume and precipitation strength information estimations based on AMSR-E data have been inputted into the numerical weather predictions. With the additional information, water vapor distribution on the ocean can be more precisely input, and that contributes to improving the accuracy of the predictions. The following images show an example of the improvement in forecasting accuracy at the time of localized heavy rain in Fukui Prefecture.

The above images are six- and nine-hour forecasts at 3:00 p.m. on July 18, 2004 (Japan time). A and B are forecast results with and without AMSR-E respectively, and C shows actual precipitation. With AMSR-E, estimated rain strength (indicated by an orange arrow) is closer to actual precipitation, thus forecast accuracy is obviously improved. Without AMSR-E, the forecasted area of precipitation is extended to the offshore of Yamaguchi Prefecture (indicated by an orange oblong), but the area gets smaller with AMSR-E. Analysis and forecast results were provided by the Japan Meteorological Agency.

For AMSR-E data to be used as initial values for numerical weather predictions, the information has to be sent in a quickly and timely manner to the Agency. In order to satisfy this requirement, the Earth Observation Center receives data directly from AMSR-E to process it and provide the information to the Agency.

The NASA earth observation satellite, AQUA, on which our Advanced Microwave Scanning Radiometer-EOS (AMSR-E) is aboard, celebrated its second anniversary on May 4, 2004. AMSR-E continues its smooth observations to provide global physical volume data (please refer to the images.) In these two years, it acquired data on the first El Nino phenomenon in the 21st century (*1) and the heat wave in Europe in the summer of 2003 (*2). It also started to distribute data on eight products, including soil moisture, in March 2004 (*3). This data can be acquired through the website of the Earth Observation Center. (*4)
Although the satellite marked it second year of service, continuous monitoring of the Earth's climatic change is still in the infancy phase. JAXA would like to keep contributing to observations of the Earth not only through existing satellites but also by planning the next generation of observation activities. We are also making efforts to inform you of climate phenomena in our region, such as the site for floating ice in the Sea of Okhotsk that was opened last winter, so that readers can study these issues that are closely related to them. As the typhoon season approaches, we are now preparing a new site for up-to-date reports.

The Earth Observation Research and Application Center (EORC) started the new site to provide updated data about floating ice of the Sea of Okhotsuk. The data are mainly acquired by the Advanced Microwave Scanning Radiometer-EOS (AMSR-E) of "Aqua", a NASA satellite. AMSR-E was developed by NASDA, one of the JAXA's predecessor organizations, and launched in May 2002 as one of the onboard equipment of "Aqua". AMSR-E has been working well since its launch.
The Sea of Okhotsk usually starts to freeze in November, and about 80% of its surface is covered by ice until mid March in average. Floating ice is moving unexpectedly fast, often at the speed of 50 cm per second.
AMSR-E takes advantage of its special feature of microwave measurement to acquire ice distribution data without being affected by weather conditions (such as clouds or light snow). In the new site, floating ice distribution images will be updated everyday by processing data transmitted from AMSR-E.
Sea ice concentration means a percentage of an ocean surface covered by sea ice in a certain ocean area. In a diagram below, deeper red indicates higher concentration that is closer to 100% ice coverage.
Floating ice usually arrives at the coastal area of Hokkaido, the most northern main island of Japan, in mid January. You can find the best timing for a floating ice site seeing tour by watching this new site.

Image : Okhotsk Sea Ice Concentration Jan,06.2004

The Advanced Microwave Scanning Radiometer for EOS (AMSR-E), which is one of the observation equipment of NASA's satellite, Aqua, is a sensor developed by NASDA to observe global water. The AMSR-E is carrying out the observation smoothly for a year and four months since its launch. On Sep. 19, we started to provide "geophysical products" followed by "brightness temperature products" that have been open to the public since June this year. Five geophysical parameters, namely sea surface temperature, sea surface wind speed, integrated water vapor, precipitation, and sea ice concentration, are provided to domestic and overseas research institutes and general users. The geophysical products are generated by combining brightness temperature data acquired through multiple observation frequencies and include user friendlier parameters. They will be used for understanding global scale water and energy circulations. For products and data, please check the following website.

Advanced Microwave Scanning Radiometer for EOS (AMSR-E) a microwave radiometer newly developed by NASDA for the observation of geophysical parameters mainly relevant to water on the Earth, has been successfully working onboard the NASA's earth observation satellite Aqua.
EORC has opened new pages of global map of geophysical parameters (level 3) browse images to show images of sea surface temperature distribution, water vapor content and sea ice concentration on the EORC home page.
These images will be updated day by day and they show the spatial and temporal change in visualized global map of geophysical parameters. However at present they are of limited parameters, other parameters will be also open gradually as the calibration and validation is progressed.
Photo: Observed image by AMSR-E

After an investigation into telemetry anomaly on the AMSR-E aboard the EOS-PM1 (Aqua) in orbit, which was launched on May 4, 2002, it was confirmed that these problems would not effect future operations. In addition, the initial checkout in orbit was completed on the AMSR-E and the satellite moved into normal orbital operations. From now on, calibration and validation of observed data, function and performance verification on ground data processing systems and the processing program development to estimate the physical quantity from observed data will be completed. The observed data will be publicized in May 2003, one year after the launch.
Photo: The data processing system for the AMSR-E

NASA's Earth observation satellite "Aqua" (formerly named EOS-PM), which carries NASDA's microwave radiometer AMSR-E, was successfully launched by a Delta II rocket at 2:54:58 (PDT) on May 4, 2002, from the Vandenberg Launch Site in California. As scheduled, the Aqua spacecraft successfully separated from the Delta II rocket on its first orbit at 3:54 (PDT), and AMSR-E was powered on at 4:50 (PDT) on May 4.

After the delivery of the AMSR-E to NASA in Los Angeles in December 1999, the spacecraft integration and test has been performed there since January 2000 and it has been completed this time.
In March, CPT (Comprehensive Performance Test), SCIF Test #5, non-flight item removal were performed at Vandenberg launch site.
In April, after the spacecraft fuelling, the mate to the launch vehicle, Aliveness Test, the fairling installation and the count down tasks, EOS-PM1 (Aqua) will be launched at 2:55 AM on May 4, 2002.
Photo: Advanced Microwave Scanning Radiometer-E

After the delivery of the AMSR-E to NASA in Los Angeles in December 1999, the spacecraft integration and test has been performed there since January 2000 and it has been completed this time.
In February, SCIF (spacecraft interface) Test #4 was performed. The spacecraft was transported to Vandenberg launch site, California on February 25.
In March, CPT (Comprehensive Performance Test), SCIF Test #5, non-flight item removal, the spacecraft mate to the launch vehicle and so on are scheduled at the launch site.
NASA announced that EOS-PM1 (Aqua) will be launched on April 18, 2002.
Photo: The spacecraft on the trailer before its transportation (AMSR-E is the gold parts on this side)

After the delivery of the AMSR-E to NASA in Los Angeles in December 1999, the spacecraft integration and test has been performed there since January 2000.
In January, a SCPT (System level Comprehensive Performance Test) was performed. Also, the AMSR-E mechanical preparation for the launch, e.g. the antenna reflector flight stow, the MLI (multi-layer insulator) closure and the non-flight item (a portion) removal, was performed. After SCIF (spacecraft interface) Test #4 in February, the spacecraftis will be transported to Vandenberg launch site, California.
NASA recently postponed the launch schedule of the EOS-PM1 (Aqua) from March 2002 to April 2002.
Photo: Advanced Microwave Scanning Radiometer-E

After the delivery of AMSR-E to NASA in Los Angels in December 1999, the spacecraft integration and test has been performed there since January 2000.
The thermal vacuum test was performed from August to October and AMSR-E worked properly during the period. Mission Test, Spacecraft Interface Test and so on are scheduled in November.

After the delivery of AMSR-E to NASA in Los Angels in December 1999, the spacecraft integration and test has been performed there since January 2000. The SCIF (Spacecraft Interface) test was performed in January. This test was to control the spacecraft in Los Angels from NASA/GSFC (Goddard Space Flight Center, in Maryland). The interface test regarding AMSR-E was performed well. The System Level CPT (Comprehensive Performance Test) prior to the thermal vacuum test is scheduled in February.

After the delivery of AMSR-E to NASA in Los Angels in December 1999, the spacecraft integration and test has been performed there since January 2000. The mechanical environmental tests (the acoustic test, the vibration test and the shock test) were performed well in November. The CPT (comprehensive performance test) after the mechanical environmental tests will be performed in December.
NASA postponed the launch schedule of EOS-PM1 (renamed to EOS Aqua) from December in 2000 to July in 2001.
Photo: The spacecraft before the mechanical environmental tests

AMSR-E before the EMC test (after the main reflector was rotated at 90 degrees)
After the delivery of AMSR-E to NASA in December 1999, the spacecraft integration and test began from January 2000. From September to October the EMC (Electromagnetic Compatibility) test was performed. The high sensitivity of AMSR-E was demonstrated during the EMC test. The mechanical environmental tests (acoustic test, vibration test and shock test) will be performed in November.

AMSR-E on the spacecraft
After the delivery of AMSR-E to NASA on December 1999, the spacecraft integration and test began from January 2000. In August the CPT (Comprehensive Performance Test) #1 was performed prior to the series of the environmental tests. EMC (Electro-magnetic compatibility) test will be performed in September.

AMSR-E on the spacecraft
After the delivery of AMSR-E to NASA in December 1999, the spacecraft integration and test began from January 2000. In June, the electrical integration on the spacecraft was performed. The CPT (Comprehensive Performance Test) #1 will be performed prior to the series of the environmental tests in July.

AMSR-E before the delivery to NASA
AMSR-E in the mechanical integration on the spacecraft After the delivery of AMSR-E to NASA, the spacecraft integration and test of NASA's spacecraft EOS Aqua (changed its name from EOS-PM1) began from January 2000. In January, the AMSR-E mechanical integration on EOS Aqua was performed. In April, the electrical integration will be performed.

The system test for the final stage of the development of AMSR-E was completed in early December. In the middle of December, AMSR-E was shipped to TRW in Los Angels that is developing NASA's spacecraft EOS-PM1.
After the verification test, NASDA delivered AMSR-E to NASA. The development that started in 1996 fiscal year has ended.
AMSR-E was opened to the press at Tsukuba Space Center before its shipping to the U.S. Integration, and the test that begins with the installation of AMSR-Eon EOS-PM1 will start from January 2000.

The system test for the final stage of the development has been conducted at Tsukuba Space Center. AMSR-E will be launched in the state of the antenna folded to put AMSR-E into the rocket fairing and the antenna will be deployed after the spacecraft is put into the orbit. Therefore, the antenna deployment mechanism has very important role. In November the antenna deployment test was conducted after the vibration test. It was verified that the mechanism functions properly. The deployment test this time is the same test as the one conducted in August after the thermal-vacuum test and the acoustic test.
Photo:AMSR-E in the antenna deployment test at Tsukuba Space Center

The system test for the final stage of the development has been conducted at Tsukuba Space Center and at the maker. The vibration test was performed to verify that AMSR-E has sustained no damage after the exposure to the vibration imposed by the launch vehicle in October. It was verified that AMSR-E had no damage.
Photo: AMSR-E in the vibration test at the maker of the flight model

The system test for the final stage of the development has been conducted at Tsukuba Space Center. The acoustic test was performed to verify that AMSR-E has sustained no damage after being exposed to the acoustic vibration imposed by the launch vehicle in July. It was verified that AMSR-E had no damage.
Photo: AMSR-E in Acoustic Test Facility at Tsukuba Space Center

The system test which is the final stage of the development is being performed at Tsukuba Space Center. The thermal vacuum test was performed to verify the AMSR-E function in the severe space environment in June and the function of AMSR-E was confirmed.
The mechanical environment tests will be performed to qualify AMSR-E for the environments imposed by the launch vehicle from this month to August.