Oeschger Centre for Climate Change Research (OCCR)

Comprehensive Historical Upper Air Network (CHUAN)

On this site we provide monthly mean historical upper-air data prior to the International Geophysical Year 1957. The data set is based on 16.4 million profiles from almost 4000 station records.

"The Comprehensive Historical Upper Air Network (CHUAN)" (Bull. Amer. Meteor. Soc., 91, DOI: 10.1175/2009BAMS2852.1): A. Stickler, A.N. Grant, T. Ewen, T.F. Ross, R.S. Vose, J. Comeaux, P. Bessemoulin, K. Jylhä, W.K. Adam, P. Jeannet, A. Nagurny, A.M. Sterin, R. Allan, G.P. Compo, T. Griesser, and S. Brönnimann (2010)

The current version is version 1.7

Download station list

Station list (ASCII tab delimited)

Station list documentation (pdf)

Download data

monthly means, corrected, adjusted to daily mean, homogenised (C)
(ASCII tab delimited, ca. 86 MB)

monthly means, uncorrected data (R)
(ASCII tab delimited, ca. 86 MB)

monthly means, supplemented (same as C, but only small subset with neighbouring stations merged) (S)
(ASCII tab delimited, ca. 0.2 MB)

The full, single ascent data (uncorrected R version) can be downloaded at http://rda.ucar.edu/datasets/ds352.0/

Download data description

Version history (pdf)

File name nomenclature (txt)

Data format description (pdf)

The station list and the data files are ASCII tab delimited .txt files.

The data files have been compressed with WinRAR.

Reconstructions of Upper-Level Temperature and Geopotential Height Fields

Here, we also provide monthly mean statistical reconstructions of upper-air fields back to 1880. The reconstructions are based on surface as well as upper-air data and calibrated with ERA-40.

"Reconstruction of Global Monthly Upper-Level Temperature and Geopotential Height Fields Back to 1880" (J. Climate, 23, 5590-5609): T. Griesser, S. Brönnimann, A. Grant, T. Ewen, A. Stickler (2010)