The fourth edition of the Institute of Atmospheric Physics (IAPv4) objective analysis product for ocean temperature and ocean heat content (OHC) mainly considers the latest developments in quality control (QC) procedures, climatology, deviation correction, vertical and horizontal interpolation, and mapping, and provides monthly data of over 6000 meters (119 layers) since 1940 (more reliable since 1957). The horizontal resolution of the dataset is 1 °× 1 °, and the vertical coverage range is from the surface to 6000 meters (119 layers), with a time range from 1940 to the present (monthly average).
The data source for the IAPv4 temperature grid product comes from the World Ocean Database (WOD), which includes all available observational data, including on-site data from XBT, CTD, Argo, Bottle, MBT, Glider, mooring, and other instruments, as well as some Chinese data
We have implemented a new data quality control system (CODC-QC) and a new climate system; The model simulation is used to guide the mapping from point measurements to grids (EnOI and dynamic sets), with some modifications made
IAPv4 was compared with the previous version IAPv3, as well as other data products, sea surface temperature (SST), and satellite observation data. Compared with IAPv3, the long-term increase of 2000 meter OHC in the upper layer of IAPv4 from 1955 to 2023 is slightly stronger, mainly due to the newly developed deviation correction. During the period of 2005-2023, the trend of 0-2000 meter OHC in IAPv4 was also higher than that in IAPv3, mainly due to updates in the quality control process. The top layer of IAPv4 is consistent with the independent SST dataset. Compared with IAPv3 and other OHC products investigated in this study, IAPv4 has a smaller monthly OHC variability, and the trend of ocean warming rate (i.e. warming acceleration) is more consistent with the net energy imbalance at the top of the atmosphere than IAPv3. The sea level budget can be closed within an uncertain range.
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CC BY 4.0 (Creative Commons Attribution 4.0 International License).
https://datapid.cn/CSTR:33685.11.IOCAS.20240117.002
http://dx.doi.org/10.12157/IOCAS.20240117.002
