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Climate-Induced Changes in Rates of Headland-Beach Progradation along the
Southern Coast of Lake Erie
Christopher R. Mattheus
Department of Geological and Environmental Sciences
Youngstown State University
Youngstown, OH 44555, U.S.A.

ABSTRACT
Isolated portions of the sediment-starved U.S. Lake Erie coast have prograded over the last 100 years in response to littoral drift disruption by
hard-structure installation. Published nautical charts offer insight into
decadal-scale sediment dynamics operating around this erosional coastline's
prograding headland beaches. Nearshore-surface models constructed from
historical bathymetry data sets show that headland-beach progradation occurs with little change in shoreface-profile shape; beach-area gain therefore
provides a metric for sediment-volume change. A time-series analysis of
beach growth, lake level, drought occurrence, and winter-ice cover suggests
that headland geomorphology is partly climate driven. Decreased rates of
beach progradation experienced along studied headlands between the late
1930s and early 1950s followed extreme drought conditions, exceptionally low lake levels, and low winter-ice covers. Reduced sediment supply to
headland beaches is inferred by hampered bluff erosion during periods of
low lake level, affiliated with less direct wave impact on bluffs, and drought
conditions, associated with reduced groundwater-related mass wasting of
bluffs. Similar drought and low-lake-level conditions existed throughout
the 1960s; however, this period experienced high winter-ice covers and
was unaffiliated with a change in headland-beach progradation rate, likely
due to diminished sediment losses from adjacent nearshore regions during winter seasons. Reduced bluff erosion of the 1930s was induced by a
combination of low lake levels and drought conditions and, along with
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nearshore-sediment losses in absence of winter-ice cover, stunted headlandbeach growth during the subsequent period of lake-level rise. A decadal
delay of headland-shoreline response to these climate extremes attests to the
nearshore system's poor buffering capacity to environmental changes altering sediment availability.
ADDITIONAL INDEX WORDS:  Nearshore, shoreface, littoral drift, bluff
erosion, sediment supply, coastal, GIS.
INTRODUCTION
Modern erosion problems are well documented for the U.S. Lake Erie
shoreline and relate to water-level changes, anthropogenic influences, lake
orientation with respect to prevailing wind, wave, and current regimes, and
bluff-shoreline exposures of friable shale and/or glacial/glaciola-custrine
materials (Carter, Benson, and Guy, 1981; Carter and Guy, 1988; Carter,
Monroe, and Guy, 1986; Foyle and Naber, 2012; Morang, Mohr, and Forgette, 2011). The NE-trending Lake Erie has a surface area of ~25,700
km2 (Figure 1a) and is the shallowest of the Great Lakes, with a maximum
depth of 64 m in its NE section (Holcombe et al., 2005). Its alignment
with respect to typical trajectories of strong storm systems, which tend to
move into the region from the west, promotes wave and current conditions
along the lake’s south-central coast that produce an eastward net-sediment
flux (Figure 1b; Beletsky, Saylor, and Schwab, 1999; Boyce et al., 1989;
Pincus, 1953). Fetch across the lake, which is largest for SW winds, helps

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