Ship- and island-based atmospheric soundings from the 2020 EUREC<sup>4</sup>A field campaign

Abstract

Abstract. To advance the understanding of the interplay among clouds, convection, and circulation, and its role in climate change, the EUREC4A and ATOMIC field campaigns collected measurements in the western tropical Atlantic during January and February 2020. Upper-air radiosondes were launched regularly (usually 4-hourly) from a network consisting of the Barbados Cloud Observatory (BCO) and four ships within 51–60° W, 6–16° N. From January 8 to February 19, a total of 812 radiosondes measured wind, temperature and relative humidity. In addition to the ascent, the descent was recorded for 82 % of the soundings. The soundings sampled changes in atmospheric pressure, winds, lifting condensation level, boundary layer depth, and vertical distribution of moisture associated with different ocean surface conditions, synoptic variability, and mesoscale convective organization. Raw (Level-0), quality-controlled 1-second (Level-1), and vertically gridded (Level-2) data in NetCDF format (Stephan et al., 2020) are available to the public at AERIS (https://doi.org/10.25326/62). The methods of data collection and post-processing for the radiosonde data set are described here.

The signature of the tropospheric gravity wave background in observed mesoscale motion

“…Data availability. The vertically gridded (Level 2) radiosounding data described by Stephan et al (2021) in NetCDF format are available to the public at https://doi.org/10.25326/62 (Stephan et al, 2020b). GOES-16 Advanced Baseline Imager data are provided by NASA's Worldview application (https://worldview.earthdata.nasa.…”

“…In addition to using them in 3D-Var, we analyze Level 2 surface-launched soundings for gravity waves. These data, which cover the ground to the stratosphere (typically 25 km) in steps of 10 m, are described in Stephan et al (2021) and are publicly available at https://doi.org/10.25326/62. Unlike the circle flights, the continuous data coverage allows us to filter them in time to a specific frequency interval, as we describe in Sect.…”

“…In this study we analyze the extensive radiosounding network (Stephan et al, 2021) of the Elucidating the Role of Clouds-Circulation Coupling in Climate (EUREC 4 A) campaign (Stevens et al, 2021). A network composed of a station at Barbados, four ships, and two aircraft collected more than 2700 vertical profiles of winds, temperature, and relative humidity over the course of 33 d. Since the ships were moving, this network sampled area-averaged divergence over different-sized regions.…”

How Rossby wave breaking modulates the water cycle in the North Atlantic trade wind region

“…However, the vertical thermodynamic structure of the lower troposphere is also strongly influenced by differential advection at higher levels. A future study on the impact of the different transport histories of air parcels arriving at various vertical levels in the troposphere is planned, using the comprehensive balloon sounding array compiled during EUREC 4 A (Stephan et al, 2020).…”

Atmospheric radiative profiles during EUREC<sup>4</sup>A

“…We refer the reader to Stephan et al (2020) and George (2020) for a complete description of the radiosonde and dropsonde data sets, and Bony et al (2017) and Stevens (2020) for an overview of the campaign strategy.…”