This section contains information on Climate Data Records (CDR), reconstructed sea level and Mean Sea Surface (MSS). 

Reconstructed Sea Level
Reconstructed sea level are sea level data that combine satellite altimetry and tide gauge or other in situ data to generate sea level pre satellite era. Typically an Empirical Orthogonal Function (EOF) is fitted to the satellite data to generate an algorithm that can be used back in time with the tide gauge data to produce global sea level data.
 
Church and White - This reconstruction is based on the findings by Church and White (2011) and produced by CSIRO.  http://www.cmar.csiro.au/sealevel/sl_data_cmar.html
 
Reconstructed Sea Level PO.DAAC - This reconstruction is based on the algorithm in Hamlington et al. (2011), which uses a Cyclo-Stationary EOF (CSEOF), which is less sensitive to long scale oscillations, such as ENSO or PDO.
 
Climate Data Record
CDRs take the data from several satellite mission and removes the biases so that there is a continuous time series between satellites. The main difference between CDR and reconstruction is that CDRs do not extrapolate data.
 
Integrated Multi-Mission Ocean Altimeter Data for Climate Research - It is an NASA MEaSUREs project that creates CDR between TOPEX/Poseidon, Jason-1 and OSTM/Jason-2.
 
Mean Sea Surface
Sea surface height and anomalies are typically not calculated from a climatology, instead a mean sea surface is used. The mean sea surface is a close approximation of the sea surface displacement due to Earth's geoid. 
 
DTU10 - Mean sea surface generated by the Technical University of Denmark