Open Access. Powered by Scholars. Published by Universities.®
Physical and Environmental Geography Commons™
Open Access. Powered by Scholars. Published by Universities.®
- Discipline
Articles 1 - 2 of 2
Full-Text Articles in Physical and Environmental Geography
Diatoms In Castor Lake (North-Central Washington, Usa) – Proxies Of Climate And Hydrologic Variation, Kelly D. Hollingshead
Diatoms In Castor Lake (North-Central Washington, Usa) – Proxies Of Climate And Hydrologic Variation, Kelly D. Hollingshead
Electronic Thesis and Dissertation Repository
This research provides a high temporal resolution (1 sample / 2-3 years) record of hydrologic variation for the last 2,000 years using a lake sediment record from Castor Lake, a closed-basin system in Washington, USA. The core was dated using 137Cs, 14C, and tephrochronology. Approximately 600 diatoms were identified and enumerated in 198 samples from a Castor Lake freeze core and Livingstone-piston core. A diatom-inference model for salinity was applied to reconstruct fossil diatom salinity. Diatom-inferred salinity for the last century tracked Palmer Drought Severity Index, indicating diatom community composition tracks effective moisture and can be used to …
Changes In The Hydrological Regime In The Upper Bow And Upper Athabasca Watersheds During The 20th Century, Heather A. Haines
Changes In The Hydrological Regime In The Upper Bow And Upper Athabasca Watersheds During The 20th Century, Heather A. Haines
Electronic Thesis and Dissertation Repository
This thesis examines 20th century regime changes for the headwaters of the Bow (1911-2005) and Athabasca (1971-2005) Rivers. Changes in precipitation and temperature associated with the Pacific Decadal Oscillation dominate the Bow streamflow record. Higher snowfall, lower mean temperatures, and greater annual discharges occur during the “cool” PDO phase (1947-1976) with lower snowfall, higher mean temperatures, and lower annual discharges during the “warm” (1925-1946, 1977-2005) phases. Any long-term linear trends in the Bow record are masked by these multidecadal trends. The Athabasca record is too short to compare to the PDO but available data show patterns similar to the …