Combination of temp reconstructions and instrumental record necessary
"The requirement for the WMO Statement was for up-to-date evidence showing how temperatures may have changed over the last 1000 years. To produce temperature series that were completely up-to-date (i.e. through to 1999) it was necessary to combine the temperature reconstructions with the instrumental record, because the temperature reconstructions from proxy data ended many years earlier whereas the instrumental record is updated every month."