Siasconset, MA Coastal Erosion Rate
Shoreline change 1.1 miles north of Siasconset, MA
Good news, and an honest one: USGS's data can't distinguish this stretch, 1.1 miles north of Siasconset, MA, from a flat trend. Whatever small movement it measured here is statistical noise, not a reliable direction, so none is claimed.
The grain of this number
USGS surveys the coast in transects spaced a few hundred feet apart; this page groups the nearest ones into a single ~3.5-mile reading for the stretch closest to Siasconset, MA, rather than showing one arbitrary line. Segment center: 41.28, -69.97. The survey behind it runs to 2007-2009, in USGS's New England / Mid-Atlantic assessment, using the LRR method. Shoreline surveys aren't repeated every year, so this is the most recent long-term measurement USGS has published for this coast, not a live reading.
What backs this reading up
This reading comes from 30 individual transects averaged together, 100% of which measured erosion rather than growth. USGS's confidence interval here is ±0.27 ft/yr. The unadjusted figure here, -0.15 ft/yr, would place it 562 of 1211 if ranked directly - but an unreliable rank isn't a useful one, which is exactly why "no significant trend" is the headline instead. Source: USGS Open-File Report 2010-1119. For scale: Pensacola Station, FL, 1237 miles away, ranks 1062 of 1211 nationally for growth, 0.7 ft/yr. 1.2 miles up the coast, Siasconset, MA shows the same lack of a significant trend.
One address near Siasconset: the Coastal Change Hazards Portal zooms past this stretch to the underlying map.