Seawater temperature at 500m depth in °C. === Original Data Source === WORLD OCEAN ATLAS 2018 Volume 1: Temperature From the World Ocean Atlas: This atlas consists of a description of data analysis procedures and horizontal maps of climatological distribution fields of temperature at selected standard depth levels of the World Ocean on one-degree and quarter-degree latitude-longitude grids. The aim of the maps is to illustrate large-scale characteristics of the distribution of ocean temperature. The fields used to generate these climatological maps were computed by objective analysis of all scientifically quality-controlled historical temperature data in the World Ocean Database 2018. Maps are presented for climatological composite periods (annual, seasonal, monthly, seasonal and monthly difference fields from the annual mean field, and the number of observations) at 102 standard depths. Citation: Locarnini, R. A., A. V. Mishonov, O. K. Baranova, T. P. Boyer, M. M. Zweng, H. E. Garcia, J. R. Reagan, D. Seidov, K. W. Weathers, C. R. Paver, I. V. Smolyar, 2019: World Ocean Atlas 2018, Volume 1: Temperature. A. V. Mishonov, Technical Ed., NOAA Atlas NESDIS 81 Citation URL: https://data.nodc.noaa.gov/woa/WOA18/DOC/woa18_vol1.pdf