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Dataset Overview | National Centers for Environmental Information (NCEI)

NOAA Climate Data Record of Microwave Sounding Unit (MSU) and Advanced Microwave Sounding Unit (AMSU-A) Mean Layer Temperature, Version 3.0

Mean Layer Temperature - NOAA

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The dataset contains three channel-based, monthly gridded atmospheric layer temperature Climate Data Records generated by merging nine MSU NOAA polar orbiting satellites, TIROS-N and NOAA-6 through NOAA-14, and six AMSU-A polar orbiting satellites, NOAA-15 through NOAA-18, MetOp-A, and NASA AQUA. These are temperatures of middle-troposphere (TMT), upper-troposphere (TUT, also known as temperature troposphere stratosphere), and lower-stratosphere (TLS), corresponding to measurements from MSU/AMSU-A channels 2/5, 3/7, and 4/9, respectively. Adjustments of observations included limb-adjustment, diurnal drift corrections, warm target temperature effect, and residual inter-satellite bias removal. Data coverage is from November 1978 to present; It is monthly global gridded dataset with 2.5 latitude by 2.5 longitude resolution. The dataset is updated each month with full Period of Record (POR) files in order to monitor operationally the change of upper air temperature.
  • Cite as: Zou, Cheng-Zhi; Wang, Wenhui; Li, Jian; and NOAA CDR Program (2015). NOAA Climate Data Record of Microwave Sounding Unit (MSU) and Advanced Microwave Sounding Unit (AMSU-A) Mean Layer Temperature, Version 3.0. [indicate subset used]. NOAA National Centers for Environmental Information. doi:10.7289/V5QF8QTK [access date].
gov.noaa.ncdc:C00935
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Distribution Formats
  • netCDF (Version: 4)
    • File Specification: The NetCDF data files comply with the Climate and Forecast (CF) Metadata Conventions and the NetCDF Attribute Convention for Dataset Discovery (ACDD).
Ordering Instructions Contact NCEI for other distribution options and instructions.
Distributor NOAA National Centers for Environmental Information
ncei.info@noaa.gov
Dataset Point of Contact Customer Engagement Branch
NOAA National Centers for Environmental Information
1-828-271-4800
ncei.orders@noaa.gov
Dataset resourceProvider Climate Data Record Program Office
DOC/NOAA/NESDIS/NCDC > National Climatic Data Center, NESDIS, NOAA, U.S. Department of Commerce
+1 828-271-4328
zou_msu_contacts@noaa.gov
Time Period 1978-11 to Present (time interval: 1-month)
Spatial Bounding Box Coordinates
West: -180.0
East: 180.0
South: -90.0
North: 90.0
Spatial Coverage Map
General Documentation
Processing Documents
  • Mean Layer Temperature - NOAA Source Code Package
    • CDR Source Code
      This source code is for reference only. The source code is provided to maintain transparency of the algorithm and processes used in creating the Climate Data Record (CDR). The source code is not intended to be portable to any computer system(s) beyond that of the original CDR producer's environment.
  • High Level Flowchart for MSU/AMSU TCDR Algorithm
  • Climate Algorithm Theoretical Basis Document for NOAA MSU/AMSU-A Mean Layer Temperature
Associated Resources
Publication Dates
  • publication: 2015-04-15
Edition Version 3.0
Data Presentation Form Digital table - digital representation of facts or figures systematically displayed, especially in columns
Dataset Progress Status Complete - production of the data has been completed
Data Update Frequency Monthly
Purpose This dataset provides advanced scientific researchers a high quality Climate Data Record (CDR) of Upper Atmospheric Layer Temperatures. It is used for monitoring and investigation of long-term temperature trend and variability for the atmospheric layers as defined by TMT, TUT, and TLS.
Use Limitations
  • See the Algorithm Theoretical Basis Document for a description of the use limitations for this dataset. The temperatures as defined by the datasets are mean layer temperatures which are not suitable for temperature trend determination at specific atmospheric levels. Satellite retrievals must be conducted to obtain level temperatures.
Dataset Citation
  • Cite as: Zou, Cheng-Zhi; Wang, Wenhui; Li, Jian; and NOAA CDR Program (2015). NOAA Climate Data Record of Microwave Sounding Unit (MSU) and Advanced Microwave Sounding Unit (AMSU-A) Mean Layer Temperature, Version 3.0. [indicate subset used]. NOAA National Centers for Environmental Information. doi:10.7289/V5QF8QTK [access date].
Cited Authors
  • Zou, Cheng-Zhi
    DOC/NOAA/NESDIS/STAR > Center for Satellite Applications and Research, NESDIS, NOAA, U.S. Department of Commerce
  • Wang, Wenhui
    DOC/NOAA/NESDIS/STAR > Center for Satellite Applications and Research, NESDIS, NOAA, U.S. Department of Commerce
  • Li, Jian
    DOC/NOAA/NESDIS/STAR > Center for Satellite Applications and Research, NESDIS, NOAA, U.S. Department of Commerce
  • NOAA CDR Program
    DOC/NOAA/NESDIS/NCDC > National Climatic Data Center, NESDIS, NOAA, U.S. Department of Commerce
Principal Investigators
  • Zou, Cheng-Zhi
    DOC/NOAA/NESDIS/STAR > Center for Satellite Applications and Research, NESDIS, NOAA, U.S. Department of Commerce
Collaborators
  • Wang, Wenhui
    DOC/NOAA/NESDIS/STAR > Center for Satellite Applications and Research, NESDIS, NOAA, U.S. Department of Commerce
  • Li, Jian
    DOC/NOAA/NESDIS/STAR > Center for Satellite Applications and Research, NESDIS, NOAA, U.S. Department of Commerce
  • NOAA CDR Program
    DOC/NOAA/NESDIS/NCDC > National Climatic Data Center, NESDIS, NOAA, U.S. Department of Commerce
Publishers
  • NOAA National Centers for Environmental Information
  • DOC/NOAA/NESDIS/NCDC > National Climatic Data Center, NESDIS, NOAA, U.S. Department of Commerce
Theme keywords Global Change Master Directory (GCMD) Science Keywords
  • Earth Science > Climate Indicators > Atmospheric/Ocean Indicators > Temperature Indicators
  • Earth Science > Spectral/Engineering > Microwave > Brightness Temperature
Data Center keywords Global Change Master Directory (GCMD) Data Center Keywords
  • DOC/NOAA/NESDIS/NCDC > National Climatic Data Center, NESDIS, NOAA, U.S. Department of Commerce
  • DOC/NOAA/NESDIS/NCEI > National Centers for Environmental Information, NESDIS, NOAA, U.S. Department of Commerce
  • DOC/NOAA/NESDIS/STAR > Center for Satellite Applications and Research, NESDIS, NOAA, U.S. Department of Commerce
Platform keywords Global Change Master Directory (GCMD) Platform Keywords
  • NOAA POES > NOAA Polar Orbiting Environmental Satellites
Instrument keywords Global Change Master Directory (GCMD) Instrument Keywords
  • MSU > Microwave Sounding Unit
  • AMSU-A > Advanced Microwave Sounding Unit-A
Place keywords Global Change Master Directory (GCMD) Location Keywords
  • Geographic Region > Global
Project keywords Global Change Master Directory (GCMD) Project Keywords
  • NOAA Climate Data Record (CDR) Program
  • NOAA OneStop Project
Data Resolution keywords Global Change Master Directory (GCMD) Horizontal Data Resolution Keywords
  • 100 km - < 250 km or approximately 1 degree - < 2.5 degrees
Global Change Master Directory (GCMD) Vertical Data Resolution Keywords
  • > 1 km
Global Change Master Directory (GCMD) Temporal Data Resolution Keywords
  • Monthly - < Annual
Global Change Master Directory (GCMD) Horizontal Data Resolution Keywords
  • 100 km - < 250 km or approximately 1 degree - < 2.5 degrees
Global Change Master Directory (GCMD) Vertical Data Resolution Keywords
  • > 1 km
Global Change Master Directory (GCMD) Temporal Data Resolution Keywords
  • Monthly - < Annual
Global Change Master Directory (GCMD) Horizontal Data Resolution Keywords
  • 100 km - < 250 km or approximately 1 degree - < 2.5 degrees
Global Change Master Directory (GCMD) Vertical Data Resolution Keywords
  • > 1 km
Global Change Master Directory (GCMD) Temporal Data Resolution Keywords
  • Monthly - < Annual
Use Constraints
  • Cite as: Zou, Cheng-Zhi; Wang, Wenhui; Li, Jian; and NOAA CDR Program (2015). NOAA Climate Data Record of Microwave Sounding Unit (MSU) and Advanced Microwave Sounding Unit (AMSU-A) Mean Layer Temperature, Version 3.0. [indicate subset used]. NOAA National Centers for Environmental Information. doi:10.7289/V5QF8QTK [access date].
  • See the Use Agreement for this CDR available on the CDR page.
  • Use liability: NOAA and NCEI cannot provide any warranty as to the accuracy, reliability, or completeness of furnished data. Users assume responsibility to determine the usability of these data. The user is responsible for the results of any application of this data for other than its intended purpose.
Access Constraints
  • Distribution liability: NOAA and NCEI make no warranty, expressed or implied, regarding these data, nor does the fact of distribution constitute such a warranty. NOAA and NCEI cannot assume liability for any damages caused by any errors or omissions in these data. If appropriate, NCEI can only certify that the data it distributes are an authentic copy of the records that were accepted for inclusion in the NCEI archives.
Fees
  • In most cases, electronic downloads of the data are free. However, fees may apply for custom orders, data certifications, copies of analog materials, and data distribution on physical media.
Lineage information for: dataset
Lineage Statement The data were produced by the NOAA Center for Satellite Applications and Research (STAR), and are archived at the NOAA National Centers for Environmental Information (NCEI). The MSU on board NOAA polar orbiting satellite series had been the primary instruments for measuring upper-air temperature profiles under all weather conditions, excluding precipitation, during 1978-2007. MSU was a microwave Dicke radiometer with four-channels to make passive measurements in the 5.5 millimeter oxygen region. The radiance measured by each frequency channel comes from a different layer of the atmosphere, depending on the strength of the absorption at that frequency. The percentage contribution of individual levels within the layer to the measured layer temperature is represented by a vertical weighting function, which is typically bell-shaped, peaking at a certain level in the height coordinate. Among these, MSU channel 1 (50.3 GHz) measured surface temperature, and channels 2, 3 and 4 measured temperatures of the middle-troposphere (TMT), upper-troposphere (TUT), and lower-stratosphere (TLS) with their weighting functions peaking respectively near 550, 250, and 100 hPa. Since 1998, AMSU-A onboard NOAA-15 and its follow-on satellites has replaced MSU. As a successor to the MSU instrument, AMSU-A has improved instrument accuracy, and with its 15 channels provides finer vertical resolution and measurements well into the upper stratosphere. Among all discrete frequency channels, channels 5, 7, and 9 share a similar spectrum frequency with MSU channel 2, 3, and 4, respectively. By merging MSU and AMSU-A observations from different satellites, long-term temperature time series are obtained for these layers for climate trend monitoring and investigation. Due to stability, continuity, global coverage, and insensitive to clouds, these time series are broadly used as an indicator of global warming.
Processor
  • NOAA/NESDIS/Center for Satellite Applications and Research
Processing Steps
  • The following steps and algorithms are needed to derive the atmospheric layer temperature TCDR: 1....Extracting IMICA-calibrated, limb-adjusted MSU swath brightness temperatures on scan positions for channels 2, 3 and 4 from the IMICA calibrated MSU orbital Level-1c datasets. 2....Extracting IMICA-calibrated (without limb adjustment) AMSU-A swath brightness temperatures on scan positions for channels 5, 7 and 9 from the IMICA calibrated AMSU-A orbital Level-1c datasets. 3....Adjusting AMSU-A radiances of off-nadir incident angles to be close to those of the nadir directions. 4....Adjusting AMSU-A brightness temperatures due to frequency differences at each scan positions to match MSU observations for their equivalent channels. 5....Adjusting the MSU channel 2 and AMSU-A channel 5 brightness temperatures for diurnal drift effect at each scan position. 6....Binning limb-, frequency-, and diurnal-adjusted brightness temperatures at scan positions into grid cells of 2.5ox2.5o spatial resolution in monthly interval for each satellite and then averaging the binned data at each grid cell to produce Level-3 layer temperature data for each satellite. 7....Removing residual inter-satellite biases including instrument temperature effect using satellite overlap observations of the Level-3 data. 8....Bias-removed, multiple satellite Level-3 temperature data are then averaged to generate a 36-year long, merged and homogeneous layer temperature TCDR from 1978 to present. The final product is saved as NetCDF format.
    Rationale: The main purpose of the merging algorithm or processing steps is to derive homogeneous temperature CDR from the sequential overlapping MSU and AMSU-A observations onboard NOAA, NASA, and MetOp polar orbiting satellites channel by channel. Deriving such time series requires a number of steps: Inter-calibrating the satellite sensors; Removing instrument temperature effects on observations; ;Adjusting the observations to a common reference time (usually chosen as local noon time) to minimize diurnal effect related to satellite orbital drifts; Adjusting observations made at different viewing angles to nadir views (limb effect); Adjusting channel frequency differences between MSU and AMSU-A equivalent channels; Removing residual inter-satellite biases and their drifts. ...The Level-1c radiances data used for deriving the layer temperature TCDR were already inter-calibrated by the Integrated Microwave Inter-Calibration Approach (IMICA, formerly known as simultaneous nadir overpass approach; Zou and Wang 2013). In addition, limb-adjusted brightness temperatures are also provided in the IMICA calibrated Level-1c files. As such, only adjustments other than sensor inter-calibrations and limb-adjustments were needed for satellite merging. The IMICA calibrated MSU/AMSU-A radiances and limb adjustments were described in details in the C-ATBD associated with the MSU/AMSU-A Level-1c radiance dataset (Zou and Wang 2013). This has substantially simplified the processing procedure for developing MSU/AMSU-A layer temperature TCDR. In the MSU/AMSU-A Version 3.0 mean layer temperature TCDR, updated limb-adjustment for AMSU-A observations were developed and used, which was described in the C-ATBD associated with the Version 3.0 dataset.
Processing Environment Computer hardware minimum configuration for data processing is as follows: Processor: 2.0GHz; Memory: 200 MB; Disk Space 200 GB; A system with multiple CPUs is preferred. Operating System can be Linux or Windows. Programming Languages: JAVA and Bash script; Compilers: Sun JAVA Compiler; External Library: NetCDF-JAVA 4.1, Jscience4.3; Storage Requirement : 200GB; Execution Time Requirement: Single CPU ~30 hours for 15 satellites - varies when using parallel computing
Processing Documents
    • Mean Layer Temperature - NOAA Source Code Package
      • CDR Source Code
        This source code is for reference only. The source code is provided to maintain transparency of the algorithm and processes used in creating the Climate Data Record (CDR). The source code is not intended to be portable to any computer system(s) beyond that of the original CDR producer's environment.
Source Datasets
  • NOAA Fundamental Climate Data Record (FCDR) of MSU Level 1c Brightness Temperature
    • NCEI Landing Page for MSU Brightness Temperature - NOAA
      Source dataset landing page with general information and access links for that dataset.
    • Description of Source: This dataset contains Level 1c inter-calibrated brightness temperatures from the Microwave Sounding Unit (MSU) sensors onboard nine polar orbiting satellites.
    • Temporal extent used: 1978-11 to 2006-09
    • Spatial extent used: N:90 S:-90 E:180 W:-180
  • NOAA Fundamental Climate Data Record (FCDR) of AMSU-A Level 1c Brightness Temperature
    • NCEI Landing Page for AMSU Brightness Temperature - NOAA
      Source dataset landing page with general information and access links for that dataset.
    • Description of Source: This dataset contains Level 1c inter-calibrated brightness temperatures from the Advanced Microwave Sounding Unit-A (AMSU-A) sensors onboard six NOAA, NASA, and MetOp polar orbiting satellites.
    • Temporal extent used: 1998-10-26 to Present
    • Spatial extent used: N:90 S:-90 E:180 W:-180
Lineage information for: repository
Processing Steps
  • 2015-04-22T00:00:00 - NOAA created the National Centers for Environmental Information (NCEI) by merging NOAA's National Climatic Data Center (NCDC), National Geophysical Data Center (NGDC), and National Oceanographic Data Center (NODC), including the National Coastal Data Development Center (NCDDC), per the Consolidated and Further Continuing Appropriations Act, 2015, Public Law 113-235. NCEI launched publicly on April 22, 2015.
Last Modified: 2023-08-10
For questions about the information on this page, please email: ncei.info@noaa.gov