Vandenberg AFB, CA Coastal Erosion Rate
Is the coast eroding 6.1 miles southwest of Vandenberg AFB, CA?
The coast 6.1 miles southwest of Vandenberg AFB, CA shows no statistically significant trend either way. USGS's transects measured a rate here, but it's smaller than the survey's own margin of error for this stretch, so calling it "eroding" or "growing" would overstate what the data actually shows.
What this reading actually covers
Nothing here is parcel-level. USGS's raw transects run every few hundred feet along the shore; this page averages the ones nearest Vandenberg AFB, CA into one ~3.5-mile reading rather than picking a single arbitrary line to represent the area. Centered near 34.69°N, 120.60°W. The survey behind it runs to 1852-2016, in USGS's California 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 75 separate transects produced this segment's rate, with 8% individually reading as erosion, rather than relying on any single survey line. USGS's confidence interval here is ±0.4 ft/yr. Taken at face value, this segment's raw 0.21 ft/yr reading would land it 931 of 1211 nationally - a number worth ignoring, since it's statistical noise rather than a real trend. Source: USGS National Shoreline Change data release (ScienceBase, DOI 10.5066/P94J0K7Z), Kratzmann 2024 / Data Report 1187. Rank 1083 nationally for growth belongs to Bayport, NY, 2602 miles from this stretch, measured at 0.83 ft/yr. 2.4 miles up the coast, Vandenberg AFB, CA shows the same lack of a significant trend.
Vandenberg AFB, CA on the source map: try the Coastal Change Hazards Portal, zoomable well past this page's ~3.5-mile grain.