Combining Data from the Distributed GRUAN Site Lauder-Invercargill, New Zealand, to Provide a Site Atmospheric State Best Estimate of Temperature

Abstract

Abstract. A Site Atmospheric State Best Estimate (SASBE) of the temperature profile above the GCOS (Global Climate Observing System) Reference Upper-Air Network (GRUAN) site at Lauder, New Zealand, has been developed. Data from multiple sources are combined within the SASBE to generate a high temporal resolution data set that includes an estimate of the uncertainty on every value. The SASBE has been developed to enhance the value of measurements made at the distributed GRUAN site at Lauder and Invercargill (about 180 km apart), and to demonstrate a methodology which can be adapted to other distributed sites. Within GRUAN, a distributed site consists of a cluster of instruments at different locations. The temperature SASBE combines measurements from radiosondes and automatic weather stations at Lauder and Invercargill, and ERA5 reanalysis, which is used to calculate a diurnal temperature cycle to which the SASBE converges in the absence of any measurements. The SASBE provides hourly temperature profiles at 16 pressure levels between the surface and 10 hPa for the years 1997 to 2012. Every temperature value has an associated uncertainty which is calculated by propagating the measurement uncertainties, the ERA5 ensemble SDs, and the ERA5 representativeness uncertainty through the retrieval chain. The SASBE has been longterm archived and obtained the following digital object identifier (doi): doi:10.5281/zenodo.1195779 The study demonstrates a method to combine data collected at distributed sites. The resulting best-estimate temperature data product for Lauder is expected to be valuable for satellite and model validation as measurements of atmospheric essential climate variables are sparse in the Southern Hemisphere. The SASBE could, for example, be used to constrain a radiative transfer model to provide top-of-the-atmosphere radiances with traceable uncertainty estimates.

Nonorographic inertia‐gravity waves over New Zealand's Southern Alps: A case study

“…During DEEPWAVE, radiosondes (Vaisala RS92‐SGPD instruments attached to Totex TA600 balloons) were launched at Hokitika, Haast, and Lauder (Figure 2d). These radiosondes had a much higher temporal resolution (1 s) and vertical resolution (1–6 m) for observations than the routine radiosondes launched from Invercargill, at the southern end of the South Island (Tradowsky et al, 2018). In the interpolation of model‐level data to the balloon tracks, both the time and location of the balloons were considered so that observation and simulation profiles match in both time and locations along the balloon track.…”

Comparison of formaldehyde tropospheric columns in Australia and New Zealand using MAX-DOAS, FTIR and TROPOMI

“…for the Australasian region. Tradowsky et al, 2018). In addition, formaldehyde vertical columns measured at Lauder using fourier-transform infrared (FTIR) spectroscopy (Vigouroux et al, 2018) are available for comparison with the MAX-DOAS measurements.…”