The CSIRO Dawn-2100 archive contains datasets for atmospheric, land and oceanographic variables for the approximate period 1850 - 2100 (dependent on model). These have been created through the concatenation of 20th century (20C3M) and other scenario (currently SRESA1B or SRESA2) data from a number of the 25 differant global climate models (GCM) from various countries. The SRESA1B_huss dataset contains the Specific Humidity variable for various GCM's and runs (multiple runs being averaged to a single file if existing) under the SRESA1B scenario (SRESA1B emissions 2001 to 2100, then constant GHG 720ppm). This variable has also been further analysed to give monthly, seasonal and annual trend data, calculated from a monthly timeseries referenced to the area-weighted mean global warming values. 14 GCM models are available with data for variables being in 12 month, annual and 4 seasons(DJF, MAM,JJA,SON) format with 40 files totaling 4.13 GB as Netcdf files. Available for internal use and analysis by CSIRO staff on the HPSC cherax.