Change search
ReferencesLink to record
Permanent link

Direct link
A practical demonstration on AMSU retrieval precision for upper tropospheric humidity by a non-linear multi-channel regression method
School of Geosciences, University of Edinburgh.
Chalmers University of Technology, Department of Radio and Space Science, Gothenburg.
Universität Bremen, Institute of Environmental Physics.
2005 (English)In: Atmospheric Chemistry And Physics, ISSN 1680-7316, E-ISSN 1680-7324, Vol. 5, no 2, 451-459 p.Article in journal (Refereed) Published
Abstract [en]

A neural network algorithm inverting selected channels from the Advance Microwave Sounding Unit instruments AMSU-A and AMSU-B was applied to retrieve layer averaged relative humidity. The neural network was trained with a global synthetic dataset representing clear-sky conditions. A precision of around 6% was obtained when retrieving global simulated radiances, the precision deteriorated less than 1% when real mid-latitude AMSU radiances were inverted and compared with co-located data from a radiosonde station. The 6% precision outperforms by 1% the reported precision estimate from a linear single-channel regression between radiance and weighting function averaged relative humidity, the more traditional approach to exploit AMSU data. Added advantages are not only a better precision; the AMSU-B humidity information is more optimally exploited by including temperature information from AMSU-A channels; and the layer averaged humidity is a more physical quantity than the weighted humidity, for comparison with other datasets. The training dataset proved adequate for inverting real radiances from a mid-latitude site, but it is limited by not considering the impact of clouds or surface emissivity changes, and further work is needed in this direction for further validation of the precision estimates.

Place, publisher, year, edition, pages
2005. Vol. 5, no 2, 451-459 p.
Research subject
Space Technology
URN: urn:nbn:se:ltu:diva-9432Local ID: 80c12e30-f88e-11db-b2dd-000ea68e967bOAI: diva2:982370
Upprättat; 2005; 20070502 (pafi)Available from: 2016-09-29 Created: 2016-09-29

Open Access in DiVA

fulltext(444 kB)1 downloads
File information
File name FULLTEXT01.pdfFile size 444 kBChecksum SHA-512
Type fulltextMimetype application/pdf

Search in DiVA

By author/editor
Buehler, Stefan
In the same journal
Atmospheric Chemistry And Physics

Search outside of DiVA

GoogleGoogle Scholar
Total: 1 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Total: 1 hits
ReferencesLink to record
Permanent link

Direct link