Identifying Nonlinear Change in Non-perennial Streamflow
Abstract
Most global waterways (e.g., rivers and streams) are non-perennial, which indicates that continuous surface flows do not occur year-round. In recent years, non-perennial streams are gaining research attention due to their importance to biodiversity and society through groundwater recharge for agriculture, etc. However, scientific methods for managing these non-perennial stream flows are still limited and many questions remain regarding the non-perennial flow distribution and spatiotemporal patterns at regional to national scales. Although nonlinearities in the characteristics of perennial streams have been studied before, these types of analyses are new for non-perennial streams. In this presentation, we will discuss findings from our ongoing investigation on the nonlinear change in non-perennial stream attributes at the catchment to continental scale. To do this, we analyzed different mathematical functions and their goodness-of-fit to identify the most appropriate functional forms for 540 gages spanning the continental United States from 1979 to 2018 to determine where and what types of nonlinear change has occurred in non-perennial streams. We find numerous nonlinearities through time including step changes and sigmoidal behavior. We will also investigate a wide range of variables and attributes, including streamflow, precipitation, temperature, etc., to determine the potential drivers for the observed nonlinearities.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2021
- Bibcode:
- 2021AGUFM.H45P1366K