Southampton, NY Coastal Erosion Rate
Is the coast eroding 1.2 miles east of Southampton, NY?
Good news, and an honest one: USGS's data can't distinguish this stretch, 1.2 miles east of Southampton, NY, 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 Southampton, NY, rather than showing one arbitrary line. Segment center: 40.88, -72.38. 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.
How solid is this number
Averaging 17 separate transects produced this segment's rate, with 100% individually reading as erosion, rather than relying on any single survey line. USGS's confidence interval here is ±0.26 ft/yr. The unadjusted figure here, -0.13 ft/yr, would place it 595 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: Wildwood Crest, NJ, 185 miles away, ranks 1185 of 1211 nationally for growth, 3.33 ft/yr. Southampton, NY, 1.4 miles off, is the adjacent measured stretch, itself no significant trend.
Southampton, NY on the source map: try the Coastal Change Hazards Portal, zoomable well past this page's ~3.5-mile grain.