The Total Carbon Column Observing Network site description for Lauder, New Zealand

Abstract

Abstract. In this paper we describe the retrievals of atmospheric trace gases from near-infrared, high-resolution solar absorption spectroscopy measurements at the Lauder atmospheric research station in New Zealand and submitted to the Total Carbon Column Observing Network (TCCON) archive.The Lauder site (45.034 • S, 169.68 • E, 370 m a.s.l.) is located within a sparsely populated region of the South Island of New Zealand and is sheltered from the prevailing wind direction by the Southern Alps, which gives the site a high number of clear-sky days and an air mass that is largely unmodified by regional anthropogenic sources. The Lauder TCCON archive consists of data from two instruments: a Bruker IFS 120HR from June 2004 to February 2010 and a Bruker IFS 125HR from February 2010 to present. The bias between the two instruments is assessed to be 0.068 % for CO 2 . Since measurements using the IFS 125HR began, the SD about the hourly mean has been better than 0.1 % for 96.81 % of CO 2 column retrievals.The retrievals have been calibrated against in situ airborne measurements to correct for biases and provide traceability to the World Meteorological Organization (WMO) scales with an accuracy of 0.1 % for CO 2 .The Lauder TCCON time series of retrieved dry-air mole fractions of CO 2 , CH 4 , N 2 O, HF, H 2 O, HDO and CO are available from the TCCON data archive.The DOIs are https://doi

Satellite and ground-based measurements of XCO<sub>2</sub> in a remote semiarid region of Australia

“…This value varies by approximately 1 % with solar zenith angle, indicating an air mass dependence in the O 2 retrievals (Pollard et al, 2017). Deviations from the characteristic values for X air are generally indicative of erroneous behavior in the measurement and retrieval system such as interferometer misalignment, tracking errors or fitting to an incorrect air mass due to timing errors, as recently reported in Pollard et al (2017). Figure 4 shows the normalized probability distribution functions (PDFs) of X air values retrieved by both instruments in 2016.…”

Satellite and Ground-based Measurements of X<sub>CO<sub>2</sub></sub> in a Remote Semi-Arid Region of Australia

“…This value varies by approximately 1% with solar zenith angle, indicating an airmass dependence in the O 2 retrievals (Pollard et al,10 2017). Deviations from the characteristic values for X air are generally indicative of erroneous behavior in the measurement and retrieval system such as interferometer misalignment, tracking errors or fitting to an incorrect airmass due to timing errors as recently reported in Pollard et al (2017).…”

Evaluation of MOPITT version 7 joint TIR-NIR X<sub>CO</sub> retrievals with TCCON

“…Ascension Island shows a special case where enhanced CO in the lower free troposphere is seen coming from biomass burning and rain forest VOC emissions in Africa. At sites far removed from local emissions (e.g., Ny-Ålesund and Lauder) the MOPITT and TCCON priors are in better agreement with each other (see e.g., Pollard et al, 2017).…”