Flow front map at 1:5000 scale

Flow front map at 1:5000 scale...

Detailed Description

This map uses a satellite image acquired in March 2014 (provided by Digital Globe) as a base to show the area around the front of the June 27th lava flow. The area of the flow on October 27, 2014, at 11:30 PM is shown in pink, while widening and advancement of the flow as mapped on October 28 at 1:00 PM is shown in red. The mapping today was focused on the immediate flow front region, and did not cover the western margin of the flow near AP‘A‘ā St. (see marked margin). Also, another lobe upslope of Cemetery Rd. is not shown in this map, but it only advanced about 30 m (33 yards) over the past day. The dotted blue lines show steepest-descent paths in the area, calculated from a 1983 digital elevation model (DEM). The flow advanced about 150 meters (164 yards) between these two mapping times, and was advancing through private property this afternoon. At the time of mapping (1 PM), the flow was 390 meters (430 yards) directly upslope from Pāhoa Village Road. The latitude and longitude of the front as of 1 PM was 19.49412, -154.95378 (Decimal Degrees; WGS84). Though not shown on this map, the flow front advanced an additional 70 meters (77 yards) by 5:30 PM. Steepest-descent path analysis is based on the assumption that the DEM perfectly represents the earth's surface. DEMs, however, are not perfect, so the dotted blue lines can be used to infer only approximate flow paths. For calculation details, see http://pubs.usgs.gov/of/2007/1264/.

Details

Image Dimensions: 3300 x 2550

Date Taken: