This dataset contains measurements from the Micro Rain Radar (MRR2), manufactured by Meteorologische Messtechnik GmbH (Metek) installed onboard the NATO Research Vessel Alliance during the Iceland Greenland Seas Project. The MRR2 is a frequency modulated (FM), continuous wave (CW) Radar (Radio Detection and Ranging) that obtains doppler spectral density at each range gate with a time resolution of 10 s. The terminal velocity of the precipitation targets (vT) is the primarily retrieved variable from these doppler spectral density observations. Additionally, drop size distribution and the corresponding moments, for example liquid water content (LWC), rain rate (RR) and Radar Reflectivity (Ze) are retrieved with post processing. The initial installation location from 03-13 Feb 2018 was midship on the weatherdeck. At Reykjavik harbour the MRR2 worked as expected, while at sea artificial signals at three elevations appeared. The artificial signals were due to an interference on the power cable or power source. On 11 Feb 2018, a separate power source for the MRR2 could be secured, and it subsequently operated without interferences after ~12 UTC that day. For further details and figures on the MRR2 and its operation in the cruise please read the attached documentation.

This dataset contains meteorological, sea water temperature, surface ocean currents and wave height, direction and period measurements from a Seawatch Wavescan meteorological buoy deployed in the northwest Iceland Sea for the Iceland Greenland seas Project (IGP). This was an international project involving the UK, US a Norwegian research communities. The UK component was funded by NERC, under the Amospheric Forcing of the Iceland Sea (AFIS) project (NE/N009754/1). The Seawatch Wavescan meteorological buoy was deployed during the first leg of the NATO Research Vessel Alliance cruise, on 21 February 2018. Its position in the northwest Iceland Sea was strategically placed adjacent to a subsurface mooring in the Eggvin Offset. The dataset contains standard meteorological variables, surface ocean currents and wave height, direction and period from the buoy. Sea water temperature measurements at 8 m depth from the co-located mooring beneath the buoy are included to replace failed sea surface temperature measurements from the buoy under the reasonable assumption that this was still within the surface ocean mixed layer in this region. Similarly, pressure measurements that failed for roughly half of the deployment are replaced by surface layer estimates from ECMWF's ERA5 reanalysis product interpolated to the position of the meteorological buoy, corroborated for the period the sensor was working. Otherwise the buoy worked well for 2.5 months, until it broke loose from its anchor and stopped recording on 6 May 2018 and was recovered soon after. Also provided in the dataset are bulk aerodynamic flux estimates generated using the COARE3.0a algorithm.