mwr3c-phys > MWR3C physical retrievals of precipitable water vapor and cloud liquid water pathData Source Type(s) > PI

The data set contains physical retrievals of PWV and cloud LWP retrieved from MWR3C measurements during the MAGIC campaign. Additional data used in the retrieval process include radiosondes and ceilometer. The retrieval is based on an optimal estimation technique that starts from a first guess and iteratively repeats the forward model calculations until a predefined convergence criterion is satisfied. The first guess is a vector of [PWV,LWP] from the neural network retrieval fields in the netcdf file. When convergence is achieved the 'a posteriori' covariance is computed and its square root is expressed in the file as the retrieval 1-sigma uncertainty. The closest radiosonde profile is used for the radiative transfer calculations and ceilometer data are used to constrain the cloud base height. The RMS error between the brightness temperatures is computed at the last iterations as a consistency check and is written in the last column of the output file. For more details on the retrieval methodology, or for questions, please contact Maria Cadeddu: mcadeddu@anl.gov

Purpose

The physical retrievals have less uncertainty than statistical retrievals provided with a standard ARM datastream. The purpose of the data set therefore is to provide improved retrievals of PWV and LWP.

Primary Measurements

Locations

  • Fixed
  • Mobile

Data Details

Developed By Maria Cadeddu
Contact Maria Cadeddu
Resource(s) Data Directory
ReadMe
Data format text file
Site MAG
Content time range 18 November 2012 - 30 September 2013
Attribute accuracy No formal attribute accuracy tests were conducted.
Positional accuracy No formal positional accuracy tests were conducted.
Data Consistency and Completeness Data set is considered complete for the information presented, as described in the abstract.Users are advised to read the rest of the metadata record carefully for additional details.
Access Restriction No access constraints are associated with this data.
Use Restriction No use constraints are associated with this data.
File naming convention siteyyyymo_retrieval.dat
Citations David Painemal, Greenwald, T, Cadeddu, M, and Minnis, P. 2016. "First extended validation of satellite microwave liquid water path with ship-based observations of marine low clouds." Geophysical Research Letters 43: 6563-6570, doi:10.1002/2016GL06906.

MP Cadeddu, Liljegren, JC, and Turner, DD. 2013. "The Atmospheric Radiation Measurement (ARM) program network of microwave radiometers: Instrumentation, data, and retrievals." Atmospheric Measurement Techniques 6: 2359-2372, doi:10.5194/amt-6-2359-2013.