The ground-based FTIR network's potential for investigating the atmospheric water cycle

• Published in: Atmospheric Chemistry and Physics
• Main Authors: M. Schneider, K. Yoshimura, F. Hase, T. Blumenstock
• Format: Article in Journal/Newspaper
• Language: English
• Published: Copernicus Publications 2010
• Subjects: Physics; QC1-999; Chemistry; QD1-999; Arctic; Kiruna; Northern Sweden; Subarctic
• Online Access: https://doi.org/10.5194/acp-10-3427-2010; https://doaj.org/article/3add661521d64032826c4819809a62d4

We present tropospheric H 2 16 O and HD 16 O/H 2 16 O vapour profiles measured by ground-based FTIR (Fourier Transform Infrared) spectrometers between 1996 and 2008 at a northern hemispheric subarctic and subtropical site (Kiruna, Northern Sweden, 68° N and Izaña, Tenerife Island, 28° N, respectively). We compare these measurements to an isotope incorporated atmospheric general circulation model (AGCM). If the model is nudged towards meteorological fields of reanalysis data the agreement is very satisfactory on time scales ranging from daily to inter-annual. Taking the Izaña and Kiruna measurements as an example we document the FTIR network's unique potential for investigating the atmospheric water cycle. At the subarctic site we find strong correlations between the FTIR data, on the one hand, and the Arctic Oscillation index and the northern Atlantic sea surface temperature, on the other hand. The Izaña FTIR measurements reveal the importance of the Hadley circulation and the Northern Atlantic Oscillation index for the subtropical middle/upper tropospheric water balance. We document where the AGCM is able to capture these complexities of the water cycle and where it fails.