ATDB MILEAGE:
The current build (May 2006) reflects official, but not as walked, mileage as of 2005-2006 (or 2174.6 total miles).
Note that mileage for some original database waypoints not included in the official 2005-2006 revisions have been projected from the published data for nearby landmarks.
Note as well that although absolute distances change from year to year, point-to-point mileage remains accurate for 99% of the database entries.
ATDB GEOCODING:
Latitudes and longitudes for Shelters included in the database were derived from the ATC's GPX data available Here and subject to the disclaimers found Here
Latitudes and longitudes for Trail Towns and Features were coded from a variety of sources reflecting variable degrees of precision (with features in general being more accurately coded than town positions).
Town positions included in the database are, by design, too generalized to serve as an appropriate navigation aid.
ATDB WEATHER DATA:
Current and forecasted weather conditions included in the database are derived from the NOAA public SOAP weather service and subject to the disclaimers found here.
The ATDB builds a daily table of 7 day NOAA weather forecasts for each waypoint in the database at 1 a.m. each day. Current conditions reported in the database are derived from this table and may be up to 24 hours old.
Links to 7 day forecasts included in the various summary and detailed waypoint lisitings return the results of a live query to NOAA service via the Sophiaknows NOAA weather client.
The listings displayed in the pop up client window represent the most recent available conditions and forecast data for the target waypoint.
ATDB HISTORY:
The ATDB was first compiled from trail notes in 2002 by Tony Pisarra, a thru hiker who completed the Trail that year.
Database mileage was initially based on the the Appalachian Trail Conservancy's 2002 Databook (reflecting 2168.8 total miles) and was amended from multiple sources to reflect 2002 as-hiked miles (2170.4 mi)
In 2004 latitude and longitude were added to the database waypoint listings for trail towns and selected features enabling topo map views as well as live NOAA forecast data queries for the coded positions.
In 2006, ATDB waypoint mileage entries were updated to reflect official published mileage for 2005-2006 (2174.6).
In addition the ATC's trail shelter gpx data (including latitude and longitude) was added to the database waypoint listings for shelters and campsites resulting in comprehensive geocoding of all ATDB waypoints.
ATDB DISCLAIMERS:
The Database is maintained and hosted as a free service by Sophiaknows.Com.
The ATDB service is provided as is. Sophiaknows makes no warranties as to its completeness, accuracy or fitness for any purpose. Users are advised to utilize and cross check trail information against multiple sources when planning a hike.
Maps, guidebooks and information concerning ongoing relocations and local conditions can be obtained through the Appalachian Trail Conservancy as well as the Regional Hiking Clubs overseeing the Trail.
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