Intercomparison of TCCON and MUSICA Water Vapour Products
Dan Weaver1, Kimberly Strong2, Nicholas M Deutscher3, Matthias Schneider4, Thomas Blumenstock5, John Robinson6, Justus Notholt3, Vanessa Sherlock6, David W T Griffith7, Sabine Barthlott4, Omaira E García8, Dan Smale6, Mathias Palm3, Nicholas B Jones9, Frank Hase10, Rigel Kivi11, Yolanda González Ramos8, Kei Yoshimura12, Eliezer Sepúlveda8, Ángel J Gómez-Peláez8, Michael Gisi4, Regina Kohlhepp4, Thorsten Warneke3, Susanne Dohe4, Andreas Wiegele4, Emanuel Christner13, Bernard Lejeune14 and Philippe Demoulin14, (1)University of Toronto, Toronto, ON, Canada, (2)University of Toronto, Department of Physics, Toronto, ON, Canada, (3)University of Bremen, Institute of Environmental Physics, Bremen, Germany, (4)Karlsruhe Institute of Technology, Karlsruhe, Germany, (5)Karlsruhe Institute of Technology, IMK-ASF, Karlsruhe, Germany, (6)NIWA National Institute of Water and Atmospheric Research, Wellington, New Zealand, (7)University of Wollongong, Centre for Atmospheric Chemistry, Wollongong, Australia, (8)Agencia Estatal de Meteorología, Izana Atmospheric Research Centre, Santa Cruz de Tenerife, Spain, (9)University of Wollongong, Centre for Atmospheric Chemistry, School of Chemistry, Wollongong, NSW, Australia, (10)Karlsruhe Institute of Technology, Institute of Meteorology and Climate Research (IMK-ASF), Karlsruhe, Germany, (11)Finnish Meteorological Institute, Space and Earth Observation Centre, Helsinki, Finland, (12)The University of Tokyo, Atmosphere and Ocean Research Institute, Tokyo, Japan, (13)Karlsruhe Institute of Technology, Atmospheric trace gas measurements and remote sensing, Karlsruhe, Germany, (14)University of Liège, Institute of Astrophysics and Geophysics, Liège, Belgium
Abstract:
We present an intercomparison between the water vapour products from the Total Carbon Column Observing Network (TCCON) and the MUlti-platform remote Sensing of Isotopologues for investigating the Cycle of Atmospheric water (MUSICA), two datasets from ground-based Fourier Transform InfraRed (FTIR) spectrometers with good global representation. Where possible, comparisons to radiosondes are also included.
The near-infrared TCCON measurements are optimized to provide precise monitoring of greenhouse gases for carbon cycle studies; however, TCCON’s retrievals also produce water vapour products. The mid-infrared MUSICA products result from retrievals optimized to give precise and accurate information about H2O, HDO, and δD. The MUSICA water vapour products have been validated by extensive intercomparisons with H2O and δD in-situ measurements made from ground, radiosonde, and aircraft (Schneider et al. 2012, 2014), as well as by intercomparisons with satellite-based H2O and δD remote sensing measurements (Wiegele et al., 2014). This dataset provides a valuable reference point for other measurements of water vapour.
This study is motivated by the limited intercomparisons performed for TCCON water vapour products and limited characterisation of their uncertainties. We compare MUSICA and TCCON products to assess the potential for TCCON measurements to contribute to studies of the water cycle, water vapour’s role in climate and use as a tracer for atmospheric dynamics, and to evaluate the performance of climate models.
The TCCON and MUSICA products result from measurements taken using the same FTIR instruments, enabling a comparison with constant instrumentation. The retrieval techniques differ, however, in their method and a priori information. We assess the impact of these differences and characterize the comparability of the TCCON and MUSICA datasets.
