If you are interested, this was discussed pretty extensively in the <a href="http://www.pprune.org/cgibin/ultimatebb.cgi?ubb=get_topic&f=71&t=000003&p=" target="_blank">Altimeter Correction Cold WX OPS</a> thread, located in the <a href="http://www.pprune.org/cgibin/ultimatebb.cgi?ubb=forum&f=71&SUBMIT=Go" target="_blank">Tech Log Archive</a>