CoRea1860+: a coupled reanalysis of the climate from 1860 to the present

Climate reanalyses are crucial for studying climate variability, understanding climate processes, and improving climate predictions. CoRea1860+ is a 30-member coupled reanalysis covering the period from 1860 to the present, developed using the Norwegian Climate Prediction Model (NorCPM) with the assimilation of sea surface temperature (SST) observations. NorCPM integrates the Norwegian Earth System Model with the ensemble Kalman filter data assimilation method. SST, available throughout the entire period, serves as the primary source of instrumental oceanic measurements before the 1950s. As a surface-input reanalysis, CoRea1860+ minimizes artifacts caused by changes in the observation network over time. By exclusively assimilating oceanic data, it provides valuable insights into the ocean’s role in driving climate system variability, including its influence on atmospheric and sea ice dynamics.