Improved variational analyses using a nonlinear humidity control variable Ingleby, N. B. ; Lorenc, A. C. ; Ngan, K. ; Rawlins, F. ; Jackson, D. R. Abstract Publication: Quarterly Journal of the Royal Meteorological Society Pub Date: October 2013 DOI: 10.1002/qj.2073 Bibcode: 2013QJRMS.139.1875I