Water tracer precipitation output from the Met Office Unified Model (GAL9.0) for 1985-2014

This dataset contains global water tracer precipitation from a historical simulation of the Met Office Unified Model (UM) for the 30 year period, 1985 to 2014. The water tracer data can be used to track the source evaporative properties of the model's precipitation and is used in the following paper:

McLaren et al. , 2025: Implementation of Water Tracers in the Met Office Unified Model, in prep.

The simulation is atmosphere only, with prescribed sea surface temperature and sea ice starting in 1979. The ‘N96’ horizontal resolution version of the UM is used which has 192 longitude points by 144 latitude points, with a mid-latitude resolution of 135km. There are 85 vertical levels with 50 levels below 18km and a fixed model lid at 85km above sea level. The scientific configuration is GAL9.0 and the UM version is 13.3.

In the dataset, the different water tracers have an associated 'water tracer number'. These are:
1 = Total precipitation
2 = Precipitation that has been sourced from Northern Hemisphere (NH) sea ice sublimation
3 = Precipitation that has been sourced from Southern Hemisphere (SH) sea ice sublimation
4 = Precipitation that has been sourced from NH open ocean evaporation
5 = Precipitation that has been sourced from SH open ocean evaporation
6 = Precipitation that has been sourced from NH land evapotranspiration
7 = Precipitation that has been sourced from SH (north of 60S) land evapotranspiration
8 = Precipitation that has been sourced from SH (south of 60S) land evapotranspiration
9-23 = Scaled flux water tracer precipitation (see McLaren et al. 2025 for details)
These are fully documented in McLaren et al. (2025).
Global climatological seasonal means for the 30 year period, 1985 - 2014, are provided.