Decoded telegrams of surface weather observations in the Southern Ocean on board the R/V Akademik Tryoshnikov during the Antarctic Circumnavigation Expedition (ACE) in the austral summer of 2016/2017. ***** Dataset abstract ***** This dataset contains decoded reports of surface weather observations in the Southern Ocean made aboard the R/V Akademik Tryoshnikov during the Antarctic Circumnavigation Expedition (ACE), in the austral summer of 2016/2017. The observations were made by a meteorologist on board the ship and sent as telegrams encoded with World Meteorological Organisation (WMO) FM 13 code form. Posteriorly, the telegrams were decoded to produce this dataset. The telegrams were recorded on a 3-hourly basis and contain information about present and past weather; latitude, longitude, speed and direction of the ship; visibility; type, height and amount of clouds; speed and direction of wind; air, dew-point and sea-surface temperatures; barometric pressure; period, height and direction of waves; concentration of sea ice; etc. For more information on this type of report, please see the WMO Manual on Codes (WMO-No.306), Volume I.1, Part A. The original encoded files have been published separately (Veledin and Gorodetskaya, 2020; DOI 10.5281/zenodo.3734884). Data files have undergone no processing or quality-checking, therefore, if the variable you need is available in another ACE dataset, it is recommended to use the quality-checked data. Quality-checked meteorological data collected during ACE have been published separately (Landwehr et al., 2019; DOI 10.5281/zenodo.3379590). ***** Original data collection ***** The data are visual and instrumental observations made at 3-hourly time intervals (observations done at 0000, 0300, 0600, 0900, 1200, 1500, 1800, 2100 UTC). The observations contain weather information at the time of observations, as well as during the previous three hours (the periods between the reporting). This dataset was derived from the raw telegrams encoded with WMO FM 13 SHIP code (Report of surface observation from a sea station) form (Veledin and Gorodetskaya, 2020; DOI: 10.5281/zenodo.3734884). The raw data files are named in the format: UBXH3mmdd.HHh where UBXH3 is the call sign of the R/V Akademik Tryoshnikov, mm=month, dd=day, HH=hours (in 24-hour clock) and h means hours. The year for this dataset will be 2016 if the month is November (11) or December (12) and 2017 if the month is January (01), February (02), March (03) or April (04). The WMO FM13 SHIP code can be found online: https://library.wmo.int/index.php?lvl=notice_display&id=13617#.XoHf4oW3Ih4 This observations recorded in this dataset were recorded as follows: Wind speed and direction: anemometer Vaisala Marine Automatic Weather Station (MAWS) 420 Cloud base height: ceilometer Vaisala CL31, part of the Vaisala MAWS420 Pressure, air temperature, dew point temperature: Vaisala MAWS420 Sea surface temperature: infrared thermometer Ship speed and direction: ship's navigation instrumentation Waves (height and period): ship's instrumentation Weather, cloud type, sea ice, land ice: visual observations ***** Data processing ***** Code used to decode telegrams can be found in the script decode_telegrams_FM13SHIP_ACE.py (Diogo and Gorodetskaya, 2020; DOI: 10.5281/zenodo.3735028). Python3 is required to run this code. Minimum requirements: Python version 3.5.1, pandas version 0.19.1, numpy version 1.11.0. ***** Quality checking ***** No quality checking has been undertaken. ***** Standards ***** This dataset does not conform to any data formats or standards. ***** Further information for interpreting the data and using the dataset ***** The data are visual and instrumental observations at 3-hourly time step. The observations contain weather information at the time of observations, as well as during the previous three hours (the periods between the reporting). The units in the 'Symbol Description' column are given for decoded data. Decoded telegrams are presented as comma-separated ascii files containing four columns as described in the file data_file_header.txt. Below is a list of variables/information and units provided in decoded telegrams. Note that the units in the column 'Symbol Description" are given for decoded data. Symbolic_Letters Symbol_Description D....D Ship call sign YYGG Day and Time of observation (UTC) iw Source and units of wind speed LaLaLa Latitude Qc Quadrant of the globe LoLoLoLo Longitude iR Indicator for inclusion or omission of precipitation data ix Indicator for type of station operation and for present and past weather data h Height above surface of the base of the lowest cloud seen VV Horizontal visibility at surface N Total cloud cover dd True direction from which wind is blowing ff Wind speed (in units indicated by iw) 1sn Sign of the Air temperature TTT Air temperature (degree Celsius) 2sn Sign of the Dew-point temperature TdTdTd Dew-point temperature (degree Celsius) PPPP Pressure at mean sea level (hectopascal) a Characteristic of pressure tendency during the preceding three hours ppp Amount of pressure tendency at station level during the preceding three hours (hectopascal) ww Present weather W1 Past weather during the preceding 3 hours (the highest code figure) W2 Past weather during the preceding 3 hours (the next highest code figure) Nh Total amount of sky covered by low (or medium clouds, if no low) cloud CL Types of Low Clouds (Sc, St, Cu, Cb)* CM Types of Medium Clouds (Ac, As, Ns)* CH Types of High Clouds (Ci, Cs, Cc)* GGgg Time of observation, in hours and minutes UTC Ds True direction of resultant displacement of the ship during the preceding three hours vs Ship average speed made good during the three hours preceding the time of observation ss Indicator for the sign and type of measurement of sea-surface temperature TwTwTw Sea-surface temperature (degree Celsius) PwPw Period of wind waves (seconds) HwHw Height of wind waves (metre) dw1dw1 True direction from which first swell waves are coming Pw1Pw1 Period of first swell waves (seconds) Hw1Hw1 Height of first swell waves (metre) dw2dw2 True direction from which second swell waves are coming Pw2Pw2 Period of second swell waves (seconds) Hw2Hw2 Height of second swell waves (metre) Is Ice accretion on ships EsEs Thickness of ice accretion on ships (centimetres) Rs Rate of ice accretion sw Indicator for the sign and type of wet-bulb temperature reported TbTbTb Wet-bulb temperature (degree Celsius) ci Concentration or arrangement of sea ice Si Stage of development bi Ice of land origin Di True bearing of principal ice edge zi Present ice situation and trend of conditions over preceding three hours *The coding of CL, CM and CH clouds is as specified in the International Cloud Atlas (WMO-No. 407), Volume I: Sc = Stratocumulus St = Stratus Cu = Cumulus Cb = Cumulonimbus Ac = Altocumulus As = Altostratus Ns = Nimbostratus Ci = Cirrus Cs = Cirrostratus Cc = Cirrocumulus ***** Dataset contents ***** - ACE_telegram_decoded_YYYY_MM_DD_HHh.csv, output data files, ASCII comma-separated - README.txt, metadata, text file - data_file_header.txt, metadata, text file - Telegram_code_format.pdf, metadata, portable document format Missing information is presented as NaN ***** Dataset contact ***** Irina Gorodetskaya, CESAM - Centre for Environmental and Marine Studies, Department of Physics, University of Aveiro, Portugal. ORCID: 0000-0002-2294-7823. Email: irina.gorodetskaya@ua.pt ***** Dataset license ***** This set of decoded meteorological telegrams are made available under the Creative Commons Attribution 4.0 International License (CC BY 4.0) whose full description can be found at https://creativecommons.org/licenses/by/4.0/ ***** Dataset citation ***** Please cite this dataset as: Veledin, V., Luis, D., and Gorodetskaya, I. (2020). Decoded telegrams of surface weather, ocean and ice state observations in the Southern Ocean on board the R/V Akademik Tryoshnikov during the Antarctic Circumnavigation Expedition (ACE) in the austral summer of 2016/2017. (Version 1.0) [Data set]. Zenodo.