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Jonathan M Friedman

Research Hydrologist

Fort Collins Science Center

Office Phone: 970-226-9318
Fax: 970-226-9230
ORCID: 0000-0002-1329-0663

2150 Centre Avenue
Building C
Fort Collins , CO 80526-8118

Supervisor: Steve Hanser
This study uses growth in vegetation during the monsoon season measured from LANDSAT imagery as a proxy for measured rainfall. NDVI values from 26 years of pre- and post-monsoon season Landsat imagery were derived across Yuma Proving Ground (YPG) in southwestern Arizona, USA. The LANDSAT imagery (1986-2011) was downloaded from USGS’s GlobeVis website ( Change in NDVI was calculated within a set of 2,843 Riparian Area Polygons (RAPs) up to 1 km in length defined in ESRI ArcMap 10.2.
This data release consists of the following components: Sex ratio data from cottonwood trees at random points on the floodplain in the North and South units of Theodore Roosevelt National Park, ND. These data were used to investigate the effects of age, height above, and distance from the channel on mortality of male and female trees of plains cottonwood (Populus deltoides subsp. monilifera) as described in the Friedman and Griffin (2017) report. Tree core and tree ring data from the North and South Units of Theodore Roosevelt National Park, North Dakota. South Unit data was collected in April 2012, North Unit data was collected in the summer and fall of 2010. The trees are located on the floodplain of the Little...
Abstract (from Old, multi-aged populations of riparian trees provide an opportunity to improve reconstructions of streamflow. Here, ring widths of 394 plains cottonwood ( Populus deltoides, ssp. monilifera) trees in the North Unit of Theodore Roosevelt National Park, North Dakota, are used to reconstruct streamflow along the Little Missouri River (LMR), North Dakota, US. Different versions of the cottonwood chronology are developed by (1) age-curve standardization (ACS), using age-stratified samples and a single estimated curve of ring width against estimated ring age, and (2) time-curve standardization (TCS), using a subset of longer ring-width...
This metadata references a comma-delimited file describing 492 digitized prints of large-format photographs from 160 viewpoints. The photographic images themselves are referenced in a separate metadata file entitled "Photographs Showing Change in Riparian Vegetation in the Grand Canyon, 1889-2012". The viewpoints were first photographed by Stanton in 1889-1890, and then re-photographed in about 1989-1992 and 2010-2012. This set of photos focuses on change in riparian vegetation and partially overlaps a larger set of Stanton viewpoints re-photographed by Webb and others and available at The file of descriptive information gives viewpoint stake...
One of the biggest challenges facing resource managers today is not knowing exactly when, where, and how climate change effects will unfold. While models can be used to predict the types of impacts that climate change might have on a landscape, uncertainty remains surrounding factors such as how quickly changes will occur and how specific resources will respond. In order to plan for this uncertain future, managers have begun to use a tool known as scenario planning. In this approach, a subset of global climate model projections are selected that represent a range of plausible future climate scenarios for a particular area. Through a series of facilitated workshops, managers can then explore different management...
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