Validation of ground-based microwave radiometers at 22 GHz for stratospheric and mesospheric water vapor
Journal article, 2009

We present a detailed intercomparison of five ground-based 22 GHz microwave radiometers for stratospheric and mesospheric water vapor. Four of these instruments are members of the Network for the Detection of Atmospheric Composition Change (NDACC). The global measurements of middle atmospheric water vapor of the Microwave Limb Sounder (MLS) onboard the Aura satellite serve as reference and allow intercomparison of the ground-based systems that are located between 45 degrees S and 57 degrees N. The retrievals of water vapor profiles from the ground-based radiation measurements have been made consistent to a large extent: for the required temperature profiles, we used the global temperature measurements of MLS and we agreed on one common set of spectroscopic parameters. The agreement with the reference measurements is better than +/- 8% in the altitude range from 0.01 to 3 hPa. Strong correlation is found between the ground-based and the reference data in the mesosphere with respect to seasonal cycle and planetary waves. In the stratosphere the measurements are generally more noisy and become sensitive to instrumental instabilities toward lower levels (pressures greater than 3 hPa). We further present a compilation of a NDACC data set based on the retrieval parameters described herein but using a temperature climatology derived from the MLS record. This makes the ground-based measurements independent of additional information and allows extension of the data set for years in a homogeneous manner.

Author

A. Haefele

University of Bern

E. De Wachter

University of Bern

K. Hocke

University of Bern

N. Kämpfer

University of Bern

G.E. Nedoluha

Naval Research Laboratory

R.M. Gomez

Naval Research Laboratory

Patrick Eriksson

Chalmers, Department of Radio and Space Science, Global Environmental Measurements and Modelling

Peter Forkman

Chalmers, Department of Radio and Space Science, Global Environmental Measurements and Modelling

A. Lambert

Jet Propulsion Laboratory, California Institute of Technology

M.J. Schwartz

Jet Propulsion Laboratory, California Institute of Technology

Journal of Geophysical Research

01480227 (ISSN) 21562202 (eISSN)

Vol. 114 23 D23305

Subject Categories

Other Environmental Engineering

Climate Research

DOI

10.1029/2009JD011997

More information

Latest update

4/5/2022 6