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Title: Top-Down Approach for Time-Variant Anthropogenic Signature Attribution in Socio-Hydrological Systems
In the Anthropocene, humans have altered the properties and processes of hydrological systems across scales. The extent of human intervention in the landscape limits the utility of traditional hydrological modelling schemes. Since purely hydrological conceptual models no longer fit these systems, hydrologists must integrate key human interventions into conceptual models of human-modified catchments. Despite the advances in analyzing the observed changes within the hydrological cycle using bottom-up (or reductionist) modelling approaches, the aptitude of top-down hydrologic schemes for socio-hydrological system analysis is still untested. Here we show the potential of top-down hydrological modelling human modified watersheds using anthropogenic hydrological signatures. Specifically, we assess the ability of the top-down modelling method in human-modified catchments to improve the representation hydrological signatures (e.g. mean monthly runoff, flow duration curve) while ensuring a sufficient, but not excessive, level of complexity in model formulation. First, we develop new conceptual models which include human hydrological modifications commonly identified in the literature. Then, we link these new features in the conceptual models to features in the hydrological signatures. We apply the proposed methodology to the Lake Mendocino Watershed in Northern California, US. We compare a purely hydrological model developed for this catchment based on natural watershed properties using naturalized streamflow to a hydrological model of the human-modified catchment using observed streamflow. We anticipate that the proposed approach contributes to the development of detection and attribution frameworks for key anthropogenic changes of observed hydrological variability and improved model performance in human-modified catchments.  more » « less
Award ID(s):
1913920
PAR ID:
10495868
Author(s) / Creator(s):
; ;
Publisher / Repository:
American Geophysical Union
Date Published:
Format(s):
Medium: X
Location:
American Geophysical Union Fall Meeting, Virtual
Sponsoring Org:
National Science Foundation
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