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Geology topics

J.M. Friedman

Publications and source records attributed to J.M. Friedman.

12 recordsLinked to original sources

Tree-ring records of variation in flow and channel geometry

We review the use of tree rings to date flood disturbance, channel change, and sediment deposition, with an emphasis on rivers in semi-arid landscapes in the western United States. As watershed area decreases and aridity increases, large floods have a more pronounced and sustained effect on channel width and location, resulting in forest area-age distributions that are farther from a steady-state exponential relation. Furthermore, forests along three major snowmelt rivers in the northern Rocky Mountains, USA, have smaller than expected areas of young trees, suggesting that high flows and channel migration have decreased since the late 1800s.

Book chapter↗

Long-term change along the Colorado River in Grand Canyon National Park (1889-2011)

The Colorado River and its riverine resources have undergone profound changes since completion of Glen Canyon Dam in 1963, as every river runner with any history in Grand Canyon will attest. Long-term monitoring data are difficult to obtain for high-value resource areas (Webb et al. 2009), particularly in remote parts of national parks, yet these data are important to determining appropriate actions for restoration of resources and (or) potential modifications of flow releases on regulated rivers. The river corridor through the bottom of Grand Canyon creates a challenging environment for change-detection monitoring techniques (Belnap et al. 2008).

Arizona↗