Sea Isle City, NJ Coastal Erosion Rate
Is the coast eroding right at Sea Isle City, NJ?
Good news, and an honest one: USGS's data can't distinguish this stretch, right at Sea Isle City, NJ, 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 Sea Isle City, NJ, rather than showing one arbitrary line. Segment center: 39.15, -74.70. Survey years: 2007-2009, method LRR, from USGS's New England / Mid-Atlantic shoreline-change assessment. That's how current the data is here, real, but not a live feed, since a shoreline survey is a major undertaking, not an annual check-in.
How solid is this number
This reading comes from 121 individual transects averaged together, 70% of which measured erosion rather than growth. The published margin on this reading runs ±0.32 ft/yr. The unadjusted figure here, -0.09 ft/yr, would place it 660 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. Costa Mesa, CA sits at national rank 1021 for growth (0.48 ft/yr), one reference point among the 1211 scored segments, 2412 miles from here. 2.5 miles away, Strathmere, NJ is the nearest other measured stretch: moderate erosion at 1.31 ft/yr.
Not this whole stretch, just Sea Isle City itself: the Coastal Change Hazards Portal is USGS's own live version of this data.