EKF400 is a monthly resolved paleo-reanalysis covering the period 1603 to 2003. Early instrumental temperature and surface pressure observations, temperature indices derived from historical documents and temperature and moisture sensitive tree-ring measurements were assimilated into an atmospheric general circulation model ensemble using a Kalman filtering technique. This data set combines the advantage of traditional reconstruction methods of being as close as possible to observations with the advantage of climate models of being physically consistent and having 3-dimensional information about the state of the atmosphere for various variables and at all points in time. Some errors are fixed with Version 1.1.
EKF400 is the first monthly resolved paleo-reanalysis covering the period 1603 to 2003. Early instrumental temperature and surface pressure observatio...
Description
EKF400 is the first monthly resolved paleo-reanalysis covering the period 1603 to 2003. Early instrumental temperature and surface pressure observations, temperature indices derived from historical documents and temperature and moisture sensitive tree-ring proxies were assimilated into an ensemble of atmospheric general circulation model (ECHAM 5.4) using a Kalman-filtering technique (Bhend et al, 2011). EKF400 is a global data set with 4x4º resolution. Due to the location of the majority of assimilated data, skill is highest in extratropical northern hemisphere land areas. Should not be used south of 60ºS. Skill is changing over time with the varying network of assimilated data.
Consistency report
The following issues of EKF400 version 1.0 have been corrected in version 1.1:
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Description
The following issues of EKF400 version 1.0 have been corrected in version 1.1:
1. In Version 1.0 there was an error in the temperature conversion from ºC to Kelvin. Previously 273.15 have been subtracted instead of being added, which resulted in obviously wrong negative temperature values in Kelvin. This has been corrected in version 1.1.
2. The second vertical level of the temperature variable had been labeled as temperature at 500 hPa but contained temperatures at 850 hPa. In version 1.1 the labels have been corrected to 850 hPa.
3. In the related article we describe that 71-year anomalies around the current year are assimilated. In version 1.0 the anomalies have sometimes been calculated over shorter periods with minor impact on the results. Now in version 1.1, anomalies are correctly calculated over a 71-year period.