Indiana University-Purdue University Indianapolis (IUPUI) / The frequency and magnitude of flooding events on the Lower Ohio River and
their relationship with climate are investigated using a ca. 2000-year-long sediment core
collected from Goose Pond, Indiana. Using high-resolution radiocarbon dating (n = 25),
late Holocene sedimentation rates were calculated for Goose Pond. Changes in sediment
accumulation rates are attributed to variations in the frequency of flooding events on the
lower Ohio River. Elevated sedimentation rates immediately following the formation of
Goose Pond ca. 2000 years ago persisted until 680 CE, suggesting regular flooding
during this interval. Between 680 and 1190 CE, sedimentation rates decreased
dramatically and abruptly, indicating a reduction in flood frequencies. Sedimentation
rates subsequently increased again at ca. 1190 CE and persisted at a similar level until
1850 CE, suggesting that flooding frequencies increased during a time that overlapped
with the Little Ice Age (LIA; 1250-1850 CE). Sedimentation rates increased again at ca.
1850 CE, reaching a 2000-year high (3.33 cm/yr) at 1970 CE and indicating a period
characterized by frequent flooding and landscape erosion. The flood record from Goose
Pond shows similarities with other Lower Ohio River flood reconstructions from Avery
Lake, IL, and Hovey Lake, IN, suggesting the Goose Pond record reflects the regional
flooding history for the lower Ohio River. Comparison with paleoclimate records from
the Midwest supports the idea that lower Ohio River flood frequencies prior to Euro
American occupation in the 1800s increased during times when winter precipitation
predominated as a result of atmospheric circulation changes resembling the Pacific North
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American mode (PNA) that appear to have been driven in part by the Pacific Decadal
Oscillation (PDO). Following Euro-American land clearance, lower Ohio River flooding
increased dramatically despite a decrease in winter precipitation. This likely reflects an
increase in runoff and erosion as a result of deforestation and landscape conversion to
intensive row crop agriculture. As climate continues to change and the Midwestern
United States continues to see an increase in precipitation, both winter and summer, flood
frequencies could be expected to increase still further.
| Identifer | oai:union.ndltd.org:IUPUI/oai:scholarworks.iupui.edu:1805/23697 |
| Date | 08 1900 |
| Creators | Pollard, Harvie Jason |
| Contributors | Bird, Broxton W., Licht, Kathy, Jacinthe, Pierre-Andre |
| Source Sets | Indiana University-Purdue University Indianapolis |
| Language | en_US |
| Detected Language | English |
| Type | Thesis |
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