I would like to know if there is a way that I would be able to automate the clearing of alarms that are older then a certain number of days old.
Here is a groovy script that you can schedule to run that will clear alarms older the X days old. It is currently set to 100 days, which you can change to meet your needs. Remember that when automatically clearing alarms if the condition is still true the alarm will fire again after it is cleared.
long now = System.currentTimeMillis();
Calendar threshold = Calendar.getInstance();
threshold .add(Calendar.DATE, -100);
server.get("AlarmService").purgeAlarms(new Date(0), threshold.getTime());
"done in "+(System.currentTimeMillis()-now)/1000+"s"
Run in script console, date is changeable -100 = 100 days